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WASP6 User's Manual

1. 2 LLL 4 42 4 0 Model Output Selection 4 43 4 2 1 Opening Model Output 4 43 4 3 Spatial Graphical Analysis 4 45 43 Overview 4 45 4 32 Spatial Grid Toolbar 4 46 4 3 3 Geographical Information System Interface 447 43 4 BMG File Creation with Digitize 4 48 4 3 5 Controlling Spatial Analy sis 4 49 4 3 6 Selecting Dataset 4 51 43 7 Selecting Slice Geometry 4 52 4 3 8 Selecting Variable 4 52 43 9 Selecting Time 4 53 4 3 10 Palette 4 53 43 11 Animation 4 53 4 3 12 Plot Mode 4 53 4 3 13 GIS Configuration 4 54 4 3 14 Layers 4 54 4 3 15 GIS Toolbar 4 55 4 4 xy Plot c coe uiu UP scm 4 56 44 1 Overview 4 56 44 2 Toolbar 4 56 4 4 3 Creating x y Plot 4 57 444 OK Cancel 4 67 4 4 5 Zooming the Axes 4 68 4 4 6 Adding an Additional Curve 4 71 44 7 Color Black amp White View 472 44 8 Observed Measured Data 4 72 4 4 9 Printing Results 4 T5 4 4 10 Creating Tabled Data 4 76 4 4 11 Curve Calculations 477 5 The Basic Water Quality Model 5 1 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 5 1 General Mass Balance Equation ii 5 1 52 The Model Network 1 1 0 5 3 5 3 The Model Transport Scheme 1 5 7 5 4 ApplicationoftheModell 5 8 6 Chemical Tracer Transport 6 1 6 1 O
2. Segments Segments Parameters Initial Concentrations Fraction Dissolved Water Velocity Function Salinity Concentration pr Temperature of Segment Temperature T 1 0000 1 0000 1 001 1 0000 1 0000 1 000 0 0000 1 0000 1 0000 1 000 0 0000 1 0000 1 0000 2 000 0 0000 1 0000 1 0000 2 000 0 0000 1 0000 1 0000 3 000 0 0000 1 0000 1 0000 3 000 0 0000 1 0000 1 0000 3 000 0 0000 1 0000 1 0000 3 000 10 0 0000 1 0000 1 0000 3 000 1 0000 Olo Ni Dion e UN Mstart E 2 A X B Paint Shop Pro Image10 s ASci WIN WASP Bl amp 10284M Figure 3 9 Environmental Parameters 3 9 3 Initial Concentrations Because WASP6 is a dynamic model the user must specify initial conditions for each variable in each segment Initial conditions include the constituent concentrations at the beginning of the simulation The products of the initial concentrations and the initial volumes give the initial constituent masses in each segment For steady simulations where flows and loadings are held constant and the steady state concentration response is desired the user may specify initial concentrations that approximate expected final concentrations For dynamic simulations where the transient concentration response is desired initial concentrations should reflect measured values at the beginning of the simulation 3 20 DRAFT Water Quality Analysis Simulation
3. oH on HW HF c an Koi P Ko Kiz E Kai Eet By definition H 10 and OH 10 the bracketed term in equation 7 10 denoted D can be written Equation 11 11 D Ko K 1 K2 Kal Kal Ko 1077 4 10 y 1077 10 Ny Equations 7 10 and 7 11 may be combined with equations 7 5 7 8 and solved for the fraction of the total chemical f occurring in each of the chemical species k given the total chemical concentration the pH and the equilibrium constants Equation 11 12 1 EE 7 Equation 11 13 IE CUP d d D Equation 11 14 Kyl K 2 10 y f D DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 11 15 ou ul 105 jl D Equation 11 16 Kal K 2 10 Y f D The rates of chemical reactions may also vary with temperature so that the equilibrium constants are a function of temperature The functional dependence of these constants on temperature may be described by the Van t Hoff equation Equation 11 17 din K _ E ai dTx RTk or in its integrated form log K Tx l0g KilTu t Ze E ra PR LES e E ad 2 303R TrTri 2 303 R Tk Tri where K equilibrium constant A frequency factor Ea standard enthalpy change for reaction kcal mole R the universal gas constant kcal mole K Ts water temperature K Ta reference temperature at which input ionization reaction constant was observed K Common S I Range Units Description
4. dt where W sedimentation velocity of the upper bed m day S sediment concentration in the upper bed g m S sediment concentration in the water g m d depth of the upper bed m For a lower bed layer Equation 7 5 d d un Swe Se dt where S sediment concentration in the lower bed g m 7 5 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Wa sedimentation velocity of the lower bed m day d depth of the lower bed m In most applications the sediment concentration of the bed will be nearly constant over time In this case the mass derivative 0S dt will be zero The resulting mass balance in the upper bed is Equation 7 6 woS wrtws Si In the lower bed Equation 7 7 Ws Si Ws Sk It should be noted that under the constant volume option WASP6 does not require a balance of sediment fluxes into and out of a bed segment The user should therefore take care that deposition scour and sedimentation velocities reflect the intended mass flux of sediment in the bed The constant volume option also has a provision for a movable upper bed layer This layer is modeled by specifying a total advective flow rate flow field one between upper bed segments Thus when a flow rate Qi is specified from upper bed segment j to upper bed segment i the sediment pore water and chemical in j are transported to i To maintain a mass balance in segment i a similar flow rate should be specified
5. Equation 8 11 NH 20 ONO tH 0 tH Thus for every mg of ammonia nitrogen oxidized 2 32 14 mg of oxygen are consumed The kinetic expression for nitrification in EUTRO contains three terms a first order rate constant a temperature correction term and a low DO correction term The frst two terms are standard The third term represents the decline of the nitrification rate as DO levels approach 0 The user may specify the half saturation constant Kwrr which represents the DO level at which the nitrification rate is reduced by half The default value is zero which allows this reaction to proceed fully even under anaerobic conditions 8 9 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 8 2 4 Denitrification Under low DO conditions the denitrification reaction provides a sink for CBOD Equation 8 12 5CH 0 5H 0 4N0 4H 755C0O 2N 12H O Thus for each mg of nitrate nitrogen reduced 5 4 12 14 mg of carbon are consumed which reduces CBOD by 5 4 12 14 32 12 mg Denitrification is not a significant loss in the water column but can be important when simulating anaerobic benthic conditions The kinetic expression for denitrification in EUTRO contains three terms a first order rate constant with appropriate stoichiometric ratios a temperature correction term and a DO correction term The first two terms are standard The third term represents the decline of the denitrification rate as DO levels
6. The user may include the effect of solids concentration on adsorption by using a value of amp of order 1 see Di Toro 1985 for more detail If the user does not provide an input value for 6 the default value will eliminate any solids effect on the partition coefficient Since collision induced desorption is only expected to occur in the water column solids dependant partitioning is only computed for water column segments where porosity is greater that 0 99 In addition to the partical interaction parameter the user must provide for a partition coefficient following option 1 2 or 3 described above Particle Interaction Parameter The user may implement solids dependent partitioning by specifying an appropriate value for constant NUX A value of order 1 will cause the input partition coefficient to decrease with increasing suspended solids following equation 7 40 Larger values of NUX will reduce the solids effect on partitioning The default value of 10 effectively eliminates this behavior Constant numbers for the solids effect on the neutral molecule are given in Table 7 7 11 6 Volatilization Volatilization is the movement of chemical across the air water interface as the dissolved neutral concentration attempts to equilibrate with the gas phase concentration Equilibrium occurs when the partial pressure exerted by the chemical in solution equals the partial pressure of the chemical in the overlying atmosphere The rate of exchange
7. SED3D handles unsteady three dimensional flow in lakes and estuaries contact CEAM for availability WASP6 is supplied with two kinetic sub models to simulate two of the major classes of water quality problems conventional pollution involving dissolved oxygen biochemical oxygen demand nutrients and eutrophication and toxic pollution involving organic chemicals metals and sediment The linkage of either sub model with the WASP6 program gives the models EUTRO and TOXI respectively This is illustrated in Figure 3 1 with blocks to be substituted into the incomplete WASP6 model The tracer block can be a dummy sub model for substances with no kinetic interactions In most instances TOXI is used for tracers by specifying no decay Transport Transport Figure 3 1 Basic WASP Structure and Kinetic Systems The basic principle of both the hydrodynamics and water quality program is the conservation of mass The water volume and water quality constituent masses being studied are tracked and accounted for over time and space using a series of mass balancing equations The hydrodynamics program also conserves momentum or energy throughout time and space WASP Version 6 0 represents a complete re design in the functionality and look and feel of the US EPA Water Quality Analysis Simulation Program WASP WASP uses the US EPA model source code as the basic engine for the model A new Windows based preprocessor was developed and inco
8. Delete EF Graph Fil Cae X cc Mstart E 2 A 8 Paint Shop Pro Imeget s ASci WIN WASP Bl amp 10304M Figure 3 20 WASP6 Environmental Time Function Definitions The user may provide information for all the time functions or toggle on off any of the functions by clicking the Use dialog box To enter information for a time function place the cursor on the desired function The time series data form for the given time function is displayed in the lower table The user should enter time date and value for the time function 3 18 Constants This data entry group includes constants and kinetics for the water quality constituents being simulated by the particular WASP model Specified values for constants apply over the entire network for the whole simulation The user selects which constant group they would like to define kinetic constants To select a Constant Group the user should click on the drop down menu for a complete list 3 33 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Constants data Ammonia Nitrate Orthophosphate LLLI Used Value Minimum Maximum ooo 000 10000 B 100 0000 100 200 000 200 Aston 2 4 Y Part Shop Po Images Figure 3 21 Kinetic Constant Group Selections Once a constant group has been selected the user is given the opportunity to enter constant data WASP6 allows th
9. Foree E C and P L McCarty 1970 Anaerobic Decomposition of Algae Environ Sci amp Technol 4 10 pp 842 849 Graf W H 1971 Hydraulics of Sediment Transport McGraw Hill New York 12 2 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Green A E S K R Cross and L A Smith 1980 Improved Analytical Characterization of Ultraviolet Skylight Photochem and Photobio 31 59 65 Hendry G S 1977 Relationships Between Bacterial Levels and Other Characteristics of Recreational Lakes in the District of Muskoka Interim Microbiology Report Laboratory Services Branch Ontario Ministry of the Environment Henrici Arthur T 1938 Seasonal Fluctuation of Lake Bacteria in Relation to Plankton Production J Bacteriol 35 129 139 Herbes S E and L R Schwall 1978 Microbial Transformation of Polycyclic Aromatic Hydrocarbons in Pristine and Petroleum Contaminated Sediments Appl and Environ Microbiology Volume 35 No 2 pp 306 316 Hutchinson G E 1967 A Treatise on Limnology Vol IL Introduction to Lake Biology and Limnoplankton Wiley New York pp 306 354 Jewell W J And P L McCarty 1971 Aerobic Decomposition of Algae Environ Sci Technol 1971 5 10 p 1023 JRB Inc 1984 Development of Heavy Metal Waste Load Allocations for the Deep River North Carolina JRB Associates McLean VA for U S EPA Office of Water Enforcement and Permits Washington DC Karickhoff S W D S Bro
10. Record 1 is input once Record 2 is repeated NUMSEG times Record 3 is then input once Record 4 is repeated NUMSYS times Records 5 and 6 are a set and are repeated as a set NUMSYS times Within each set Record 5 is entered once and Record 6 is repeated NUMSYS times 6 2 9 Initial Conditions Because WASP6 is a dynamic model the user must specify initial conditions for each variable in each segment Initial conditions include the chemical concentrations at the beginning of the simulation The product of the initial concentrations and the initial volumes give the initial constituent masses in each segment For steady simulations where flows and loadings are held constant and the steady state concentration response is 6 12 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 desired the user may specify initial concentrations that are reasonably close to what the final concentrations should be For dynamic simulations where the transient concentration response is desired initial concentrations should reflect measured values at the beginning of the simulation In addition to chemical concentrations the dissolved fractions must be specified for each segment at the beginning of the simulation For tracers the dissolved fractions will normally be set to 1 0 For tracers as well as dissolved oxygen eutrophication and sediment transport the initial dissolved fractions remain constant throughout the simulation For organi
11. Ry death T Rs settling T1 Figure 9 2 Phytoplankton kinetics It is convenient to express the reaction term of phytoplankton S4 as a difference between the growth rate of phytoplankton and their death and settling rates in the volume V That is Equation 9 1 S a7 Gy Dij ksuj P where Su reaction term mg carbon L day P phytoplankton population mg carbon L Gy growth rate constant day Dy death plus respiration rate constant day 9 4 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 ka J The subscript 1 identifies the quantities as referring to phytoplankton type 1 only one type is considered in this particular model the subscript j refers to the volume element being considered The balance between the magnitude of the growth rate and death rate together with the transport settling and mixing determines the rate at which phytoplankton mass is created in the volume element V In subsequent text and in figures subscripts i and j will be omitted unless needed for clarity settling rate constant day segment number unitless 9 1 5 Phytoplankton Growth The growth rate of a population of phytoplankton in a natural environment is a complicated function of the species of phytoplankton present and their differing reactions to solar radiation temperature and the balance between nutrient availability and phytoplankton requirements The available information is not suffic
12. The nom point source file is an external file that contains a time series of loads kg day for a given segment and system This file is typically created either by the user manually or using other software like the Stormwater Management Model SWMM in conjunction with the Linked Watershed Waterbody Model This file can be used to provide loading information to WASP6 on virtually any time scale from timestep to timestep to year average loads 3 7 7 Hydrodynamics There are currently three surface flow options available for WASP The first two options pertain to how WASP will calculate the exchange of mass between adjoining segments with flow in both directions across a segment interface The three flow options available for surface water flow are 1 WASP will calculate net transport across a segment interface that has opposing flow WASP will net the flows and move the mass from the segment that has the higher flow leaving If the opposed flows are equal no mass is moved 2 Pertains to mass and water being moved without regard to net flow 3 13 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 3 This option is used when linking WASP to a hydrodynamic model When option 3 is selected the user cannot provide any additional surface flow information Upon execution of a WASP input dataset using option 3 the hydrodynamic linkage file must already be created and exist in the directory that the input dataset resides The
13. Activation Energy kcal mole K The user may specify activation energies for each chemical using constant EOX Constant numbers are summarized in Table 7 17 If EOX is omitted or set to 0 oxidation rates will not be affected by temperature 11 44 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Reference Temperature C The user may specify the reference temperature at which oxidation rates were measured using constant TREFO Constant numbers are summarized in Table 7 17 If a reference temperature is not supplied then a default of 20 C is assumed Oxidant Concentration _mole L The user should specify segment variable oxidant concentrations using parameter 13 OXRAD Group G Record 4 PARAM LI13 11 10 Biodegradation Bacterial degradation sometimes referred to as microbial transformation biodegradation or biolysis is the breakdown of a compound by the enzyme systems in bacteria Examples are given in 8 Although these transformations can detoxify and mineralize toxins and defuse potential toxins they can also activate potential toxins Biodegradation encompasses the broad and complex processes of enzymatic attack by organisms on organic chemicals Bacteria and to a lesser extent fungi are the mediators of biological degradation in surface water systems Dehalogenation dealkylation hydrolysis oxidation reduction ring cleavage and condensation reactions are all known to occur either metabolicall
14. Boundary Load Scale amp Conversion Factor The boundary scale and conversion factors are specified for each individual system The conversion factor can be used for converting the boundary time series information to the appropriate concentration units used by WASP6 The scale factor can be used to attenuate the boundary concentrations without re entering the time series data An example would be if the user wanted to know what the effects of doubling the loads would be on water quality Instead of re entering the time series data setting the scale factor to 2 would cause WASP6 to multiple the times series by 2 3 16 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 3 9 Segmentation Screen This data entry form allows the user to define the number of segments that will be considered in the simulation Segments are the spatial component in which WASP6 solves its set of equations Segments have volume environmental and constituent concentrations associated with them The segment data entry form has four tables associated with them 1 Segment Definition 2 Environmental Parameters 3 Initial Conditions 4 Fraction Dissolved 3 9 1 Segment Definition The segment definition screen is where the user provides segment specific geometry information It is import that the user has a good understanding in how their water body will be segmented prior to entering the information on this screen AScl WIN AWASP Standard C wi
15. Reaeration U S Public Health Service Public Health Bulletin No 146 75 pp Reprinted by U S DHEW PHA 1958 Thomann R V 1975 Mathematical Modeling of Phytoplankton in Lake Ontario 1 Model Development and Verification U S Environmental Protection Agency Corvallis OR EPA 600 3 75 005 Thomann R V R P Winfield D M Di Toro and D J O Connor 1976 Mathematical Modeling of Phytoplankton in Lake Ontario 2 Simulations Using LAKE 1 Model U S Environmental Protection Agency Grosse Ile MI EPA 600 3 76 065 Thomann R V R P Winfield and J J Segna 1979 Verification Analysis of Lake Ontario and Rochester Embayment Three Dimensional Eutrophication Models U S Environmental Protection Agency Grosse Ile MI EPA 600 3 79 094 Thomann R V and JJ Fitzpatrick 1982 Calibration and Verification of a Mathematical Model of the Eutrophication of the Potomac Estuary Prepared for Department of Environmental Services Government of the District of Columbia Washington D C Tsivoglou E E and J R Wallace 1972 Characterization of Stream Reaeration Capacity U S Environmental Protection Agency Washington DC EPA R3 72 012 Warburg O and E Negelein 1923 Uber den einfluss der Wellenlange auf den Energieumsatz bei der Kohlensaureassimilation A Phys Chem 106 191 218 12 5 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Weast R C and M J Astle ed 1980 CRC Handbook of Chemistry a
16. Reference Latitude degree and tenths The user may specify the latitude at which the reference surface water photolytic rates were measured using constant RFLATG Values for chemicals 1 2 and 3 can be entered using constant numbers 288 888 and 1488 respectively Maximum Absorption Wavelength nm The user should specify the wavelength of maximum absorption using constant LAMAXG Values for the neutral specie of chemicals 1 2 and 3 can be entered using constants 296 896 and 1496 respectively Separate values can be entered for each ionic specie Latitude degrees and tenths The user should specify the latitude of the waterbody using constant 4 LATG Cloud Cover tenths The user should specify the mean monthly or annual average cloud cover using constant CLOUDG Monthly values can be entered using constant numbers 11 22 the annual average can be entered using number 23 Light Intensity The user can specify time variable normalized light intensity dimensionless using time function 15 PHTON This function is used to adjust the measured rate constant under controlled reference light intensity to a predicted rate constant under ambient light intensity The default value for this function is 1 0 Light Extinction Coefficient mi The user can specify segment light extinction coefficients for the photochemically active light using parameter 12 XKE2 When this number is zero the extinction coefficients are calculated f
17. Theme in ArcView The best method for creating this layer is to create a base map layer out of ArcView This layer should contain the waterbody being modeled my WASP6 Draw the segmentation on the printed map If the segmentation includes sub surface segments you may need to create yet another layer Once the segmentation has been drawn on the base map place the map in your digitizer and register the map following the directions provided in the online help Once the map has been registered the user must digitize the segment polygons To do this the user must add a new theme with a separate polygon for each segment The user will need to create a database table of attributes for this layer This database contains basic information that the post processor uses to align the model predicted results with the correct segment When creating this table the user is required to have at least one field SEGID This field must be called SEGID and be a string field An optional field that can be added is LABEL LABEL is a string field as well The LABEL field can be used to put an alphanumeric 4 47 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 description next to the segment on the spatial plot The user is referred to the ArcView documentation on how to create edit and modify tables Attributes of Network shp She A SEG Figure 4 3 Model Database Definitions 4 3 4 BMG File Creation with Digitize Before a spati
18. This formulation multiplies the two terms in 5 12 It is not generally recommended Figure 9 3 presents plots of G N versus DIN and DIP with Kan 25 ug N L and Kp 1 ug P L respectively The upper plot shows the standard Michaelis Menten response curve to various concentrations of the inorganic nutrients As can be seen no significant reduction in growth rate is achieved until DIN is less than 200 ug L 0 2 mg l or until DIP is less than 8 ug L 0 008 mg l The lower plot on Figure 9 3 uses an expanded nutrient scale and shows the Michaelis Menten formulation in a slightly different format Here the impact of the function may be evaluated quite readily For example a particular reach of the water body may have concentrations of DIN equal to 100 ug L This corresponds to a 20 reduction in the growth rate Xgw 0 8 In order for phosphorus to become the limiting nutrient in the same reach dissolved inorganic phosphorus must reach a level of 4 ug L or less It should also be noted that if upstream nitrogen controls were instituted such that DIN was reduced to 60 ug L for that same reach then a further reduction in DIP to 2 5 ug L would be required to keep phosphorus as the limiting nutrient In other words as water column concentrations of DIP begin to approach growth limiting levels due to continued reduction in point source phosphorus effluents any nitrogen control strategies that might be instituted would require additional levels of phos
19. Time this mode animates the results for a single variable forward backward in time This is the preferred mode of the spatial analysis grid 2 Variable this displays the shaded results for each of the variables in the model output file Pressing the forward backward icon will cause the spatial animation grid to display the results for each of the variables 3 Slice this option displays the results for a given variable over the range of slices views found in the BMG file Figure 4 4 illustrates the configuration screen for the spatial analysis grid non GIS 4 49 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Spatial Plot Parameters fiinsesooo m 1985 0 00 fiinsesooo m Segment Depth m 7 Figure 4 4 Spatial Analysis Configuration Non GIS The GIS option works much like the other with the exception of the ability to display individual GIS layers 4 50 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 E Post processor EXAMPLE Segment Depth m at 1 1 1985 0 00 im dE xi al File Edi View GIS Window Help 8 x 4 4 nl gt gt gt amp Ex zz 2 a CAPS NUM OVA Mstart A X W Paint Shop Pio maget__ E Post processor EX Bl amp 221m Figure 4 5 Spatial Analysis View GIS 4 3 6 Selecting Dataset Because more than one model simulation result file can be loaded at a time t
20. Water Quality Analysis Simulation Program WASP Version 6 0 will delete the corresponding segment pairs lower left table and the dispersion time function lower right table To insert exchange functions for surface dispersion highlight the Surface dispersion exchange field upper left table go over to the exchange function table upper right table and press insert The bottom tables are a function of the selection in the upper tables Segment Pairs The segment pairs define the between which an exchange will occur It does not matter in which order they are defined Neither the preprocessor nor the model makes any checks to make sure the segments are connected in any manner Connectivity is the responsibility of the user Cross Sectional Area Cross sectional areas are specified for each dispersion coefficient reflecting the area through which mixing occurs These can be surface areas for vertical exchange such as in lakes or in the benthos Areas are not modified during the simulation to reflect flow changes Characteristic Mixing Length Mixing lengths or distance are specified for each dispersion coefficient reflecting the characteristic length over which mixing occurs These are typically the lengths between the center points of adjoining segments A single segment may have three or more mixing lengths for segments adjoining longitudinally laterally and vertically For surficial benthic segments connecting water column segm
21. and 1486 for chemicals 1 2 and 3 respectively Molar Absorptivity L mole cm Inl0 The user may specify molar absorptivity values for each ionic specie over 46 wavelengths using constant ABS The wavelengths by number are listed in Tables 7 12 and 7 13 Absorptivity values for each ionic specie apply across all phases aqueous DOC sorbed sediment sorbed Constant numbers for the neutral ionic specie are summarized in Table 7 15 Quantum Yield moles einstein The user may specify reaction quantum yield values for each phase dissolved DOC sorbed sediment sorbed and each ionic specie using constant QUANTG Constant numbers for the neutral molecule are summarized in Table 7 15 QUANTG refers to the dissolved neutral chemical QUANTG refers to the DOC sorbed neutral chemical QUANTG3 refers to the sediment sorbed neutral chemical Julian Date The user should specify the Julian date for the beginning of the simulation using constant 1 TO Elevation m The user should specify the average ground QUANTGu 551 1151 1751 QUANTG 2 556 1156 1756 QUANTG 31 1161 1761 elevation using constant 3 ELEVG Latitude degrees and tenths The user should specify the latitude of the waterbody using constant 4 LATG Light Option Using constant 6 XLITE the user has a choice of options controlling how TOXI computes and uses light intensity O do not compute light 1 compute annual average light intensity 2 co
22. is to be simulated the user should add a single benthic segment underlying all water column segments This benthic segment will merely act as a convenient sink for settling BOD Model calculations within this benthic segment should be ignored Figure 3 8 8 8 8 Transport Parameters This group of parameters defines the advective and dispersive transport of simulated model variables Number of Flow Fields To simulate settling the user should select solids 1 flow under advection The user should also select water column flow Figure 3 14 Particulate Transport mi sec Time variable settling and resuspension rates for particulate BOD can be input using the Solids 1 continuity array BQ and the time function QT For each solids flow field cross sectional exchange areas m for adjacent segment pairs are input using the spatially variable BQ Time variable settling velocities can be specified as a series of velocities 8 15 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 in m sec versus time If the units conversion factor is set to 1 157e 5 then these velocities are input in units of m day These velocities are multiplied internally by cross sectional areas and treated as flows that carry particulate organic matter out of the water column Figure 3 14 8 3 4 Boundary Parameters This group of parameters includes boundary concentrations waste loads and initial conditions Boundary concentrations must be specif
23. mg L day K effective rate coefficient for chemical c reaction k day Yu yield coefficients for production of chemical i from chemical c undergoing reaction k mg mg 8 illustrates some of the linked reactions that can be simulated by specifying appropriate yield coefficients 10 6 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 10 4 Model Implementation To simulate simple toxicants with WASPS6 use the preprocessor to create a TOXI input file The model input dataset and the input parameters will be similar to those for the conservative tracer model as described in Chapter 2 To those basic parameters the user will add benthic segments solids transport rates and transformation parameters During the simulation solids and toxicants will be transported both by the water column advection and dispersion rates and by these solids transport rates In WASPSO solids transport rates in the water column and the bed are input via up to three solids transport fields as described in Chapter 3 The transport of the particulate fraction of toxicants follows the solids flows The user must specify the dissolved fraction ie 0 0 and the solids transport field for each simulated solid under initial conditions To simulate total solids solids 1 must be used 10 4 1 Model Input Parameters This section summarizes the input parameters that must be specified in order to solve the simple toxicant equations
24. polychlorinated biphenyls halogenated aliphatic hydrocarbons halogenated ethers monocyclic aromatics phthalate esters polycyclic aromatic hydrocarbons and nitrosamines Organic chemicals can enter the aquatic environment by various pathways including point source waste discharges and nonpoint source runoff Some of these organic chemicals can cause toxicity to aquatic organisms or bioconcentrate through the food chain Humans may be affected by ingesting contaminated water or fish Criteria for protecting human health and indiginous aquatic communities have been promulgated for some organic chemicals Several environmental processes can affect the transport and fate of organic chemicals in the aquatic environment The most important include physical processes such as hydrophobic sorption volatilization and sedimentation chemical processes such as ionization precipitation dissolution hydrolysis photolysis oxidation and reduction and biological processes such as biodegradation and bioconcentration WASP6 explicitly handles most of these excluding only reduction and precipitation dissolution If the kinetics of these reactions are described by the user they also can be included as an extra reaction WASP6 allows the simulation of a variety of processes that may affect toxic chemicals However WASP6 makes relatively few assumptions concerning the particular processes affecting the transport transformations and kinetic reactions The mod
25. segment and time variable rate constants and flow and wind calculated rate constants These options are described in the Streeter Phelps section Photosynthesis Rate day The average phytoplankton growth rate constant and temperature coefficient can be input using constants KIC and KIT respectively For DO balance simulations where phytoplankton dynamics are bypassed the growth rate constant must reflect average light and nutrient limitations in the water body Respiration Rate day The average phytoplankton respiration rate constant and temperature coefficient can be input using constants KIRC and KIRT respectively 8 6 Nonlinear DO Balance The nonlinear DO balance equations add feedback from DO concentrations to terms in the linear DO balance equations presented above This feedback can become important in inhibiting 8 26 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 nitrification and carbonaceous oxidation and in promoting denitrification where low DO concentrations occur For this level of analysis the linear DO balance equations presented above are supplemented with nonlinear terms for carbonaceous oxidation nitrification and denitrification These terms are presented in Table 8 1 The environment transport and boundary parameters required to implement the nonlinear DO balance are the same as those in the linear DO balance presented above The user should supplement the transformation parameters
26. 0 Only the particulate fraction of BOD will be subject to settling Figure 3 11 Figure 3 11 8 3 5 Transformation Parameters This group of parameters includes spatially variable parameters constants and kinetic time functions for the water quality constituents being simulated Parameter values are entered for each segment Specified values for constants apply over the entire network for the whole simulation Kinetic time functions are composed of a series of values versus time in days 8 16 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Water Temperature C Segment variable water temperatures can be specified using the parameter TMPSG parameter TMPEN and time functions TEMP 1 4 should be omitted Temperatures will remain constant in time Sediment Oxygen Demand g m day Segment variable sediment oxygen demand fluxes can be specified using the parameter SOD1D Values should be entered for water column segments that are in contact with the bottom of the water body BOD Doeoxygenation Rate day The BOD deoxygenation rate constant and temperature coefficient can be specified using constants KDC and KDT respectively Reaeration Rate day There are three options for specifying reaeration rate constants in EUTRO In the first option a single reaeration rate constant can be specified using constant K2 An internal temperature coefficient of 1 028 is used with this option If K2 is not entered or i
27. 0 25 mg N mg C D eoxygenation rate 20 C Temp coeff ka Ea 0 21 0 16 day 1 047 Half saturation constant for oxygen Ksop 0 5 mg O2 L limitation Nitrification rate 20 C Temp coeff ki En 0 09 0 13 day 1 08 Half saturation constant for oxygen Kwir 0 5 mgN L limitation r D enitrification rate 20 C Temp coeff kop E2p day 1 08 Half saturation constant for oxygen Kwos 0 1 mg N L limitation Phytoplankton growth rate Gri 0 1 0 5 day Phytoplankton resp iraion rate 20 C k r 0 125 day Temperature coeff Ein 1 045 Sediment O xygen D emand T emp coeff SOD Es 0 2 4 0 g m2 day 1 08 Reaeration rate 20 C Temp coeff ko Ea 1 028 day DO saturation Cs Eq 4 8 mg O2 L Fraction dissolved CBO D fps 0 5 none Organic matter settling velocity Vs3 m day 8 2 1 Reaeration Oxygen deficient i e below saturation waters are replenished via atmospheric reaeration The reaeration rate coefficient is a function of the average water velocity depth wind and temperature In EUTRO the user may specify a single reaeration rate constant spatially variable reaeration rate constants or allow the model to calculate variable reaeration rates based upon flow or wind Calculated reaeration will follow either the flow induced rate or the wind induced rate whichever is larger EUTRO calculates flow induced reaeration based on the Covar method Covar 1976 This method calculates reaeration as a function of velocity and depth by o
28. 10 mg L Depth of water column segment D 0 1 10 m Reaction quantum yield fraction for specie i in phase j Oj 0 0 5 moles E Molar absorptivity by wavelength k by specie i amp i 0 L mole an In 10 Waterbody elevation ELEVG 0 5000 m Waterbody latitude L 0 90 degrees Reference latitude Lrf 0 90 degrees Cloud cover fraction of sky Cc 0 10 tenths Air type rural urban maritime or tropospheric AIRTYG 1 4 Relative humidity RHUMG 0 100 percent Atmospheric turbidity in equivalent aerosol layer ATURBG 0 km thickness Ozone content OZONEG 0 cm NTP Implementation The TOXI photolysis data specifications are summarized in Table 7 14 In addition an overall first order rate constant may be supplied by the user for each chemical as presented in Chapter 6 If the overall first order rate constant is specified it will be used regardless of other input specifications For the photolysis computations described in this chapter input requirements are described below 11 8 4 Photolysis Option 1 In option 1 TOXI computes the sunlight absorption and the surface photolytic decay rate Photolysis Option The user should select the photolysis option using constant XPHOTO 0 no photolysis 1 photolysis rates will be computed from molar absorptivity 2 photolysis 11 39 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 rates will be extrapolated from measured surface rates Use constant numbers 286 886
29. 2 Either the Di Toro or the Smith formulation can describe light limitation The Smith formulation implements equations Equation 9 5 through Equation 9 7 These equations predict the carbon to chlorophyll ratio based on the availability of light and then predict the saturating light intensity based on the carbon to chlorophyll ratio Other terms included in the intermediate kinetics equations are the phytoplankton effect on mineralization of organic phosphorus and nitrogen the dissolved oxygen limitation on nitrification the denitrification reaction and zooplankton grazing The nonlinear DO balance equations can become important in inhibiting nitrification and carbonaceous oxidation and in promoting denitrification where low DO concentrations occur 9 38 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 All eight state variables are simulated in intermediate eutrophication simulations During calibration of the model to observed data however the user may want to bypass certain variables or hold them constant Nutrients can be held at observed concentrations for instance while phytoplankton growth and death rates are calibrated 9 7 1 Environment Parameters These parameters define the basic model identity including the segmentation and control the simulation Systems Select simulate for all variables During calibration the user may select constant or bypass for any selected variables Segments Wa
30. 2 1 Hydrodynamic Linkage For unsteady flow in long networks lag times may become significant and hydrodynamic simulations may be necessary to obtain sufficient accuracy Realistic simulations of unsteady transport can be accomplished by linking WASP6 to a compatible hydrodynamic simulation This linkage is accomplished through an external file chosen by the user at simulation time The hydrodynamic file contains segment volumes at the beginning of each time step and average segment interfacial flows during each time step WASP6 uses the interfacial flows to calculate mass transport and the volumes to calculate constituent concentrations Segment depths and velocities may also be contained in the hydrodynamic file for use in calculating reaeration and volatilization rates The first step in the hydrodynamic linkage is to develop a hydrodynamic calculational network that is compatible with the WASP6 network The easiest linkage is with link node hydrodynamic models that run on equivalent spatial networks An example is given in Figure 6 1 Note that each WASP6 segment corresponds exactly to a hydrodynamic volume element or node Each WASP6 segment interface corresponds exactly to a hydrodynamic link denoted in the figure with a connecting line 6 2 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Correspondence of Network SOOO 96100 0 0 Q DYNHYD Wasp DYNIT D W ASIP Map Juecio Segments Figure 6 1
31. 20 C3 C pip K pip M C pip The dissolved and particulate fractions may be expressed respectively as Equation 9 21 _ Cor _ 1 jet e e C3 I K pp M Equation 9 22 f C pip 2 K pip M C5 I K pp M A wide range of partition coefficients is found in the literature Thomann and Fitzpatrick 1982 report values between 1 000 and 16 000 Using a range in partition coefficients from 1 000 16 000 and a range of inorganic solids of from 10 to 30 mg L in the water column leads to a range in the fraction particulate inorganic phosphorus of from 0 01 to 0 33 In EUTRO the dissolved and particulate phosphorus phases are assigned as spatially variable time constant fractions of the total inorganic phosphorus Equation 9 23 C pipj f p Gsi Equation 9 24 C pip 1 pai Cai where 9 20 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 C3 the total inorganic phosphorus in segment i mg L f the fraction of the total inorganic phosphorus assigned to the dissolved phase in segment i Copi the equilibrium dissolved inorganic phosphorus in segment i available for algal uptake mg L Copi the equilibrium sorbed inorganic phosphorus in segment i which may then settle to the sediment layer from the water column mg L 9 2 5 Settling Particulate organic and inorganic phosphorus settle according to user specified velocities and particulate fractions Particulate organic phosphorus is equated to s
32. 3 1 Streeter Phelps 8 14 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 8 32 Environment Parameters 8 15 8 3 3 Transport Parame ters 8 15 8 3 4 Boundary Parameters 8 16 8 3 5 Transformation Parameters 8 16 8 4 Modified Streeter Phelps 1 1 1 8 18 84 1 Environment Parameters 8 20 8 4 2 Transport Parameters 8 20 8 4 3 Boundary Parameters 8 21 8 4 4 Transformation Parameters 8 22 8 5 Full Linear DO Balance Z Z222 8 22 8 5 1 Environment Parameters 8 24 8 52 Transport Parameters 8 24 8 5 3 Boundary Parameters 8 25 8 5 4 Transformation Parameters 8 26 8 6 Nonlinear DO Balance 8 26 9 Eutrophication 9 1 9 1 Overview of WASP6 Eutrophication 9 1 9 1 1 Phosphorus Cycle 9 3 9 12 Nitrogen Cycle 9 3 9 1 3 Dissolved Oxygen 9 3 9 1 4 Phytoplankton Kinetics 9 3 9 1 5 Phytoplankton Growth 9 5 9 1 6 Phytoplankton Death 9 12 9 1 7 Phytoplankton Settling 9 14 9 1 8 Summary 9 14 9 1 9 Stoichiometry and Uptake Kinetics 9 15 9 20 The Phosphorus Cycle 1 1 9 16 9 2 1 Phytoplankton Growth 9 18 9 22 Phytoplankton Death 9 18 92 3 Mineralization 9 18 9 24 Sorption 9 18 9 25 Settling 9 21 9 3 The Nitrogen Cycle aJ 9 21 9 3 1 Phytoplankton Growth 9 23 9 32 Phytoplankton Death 9 24 9 3 3 Mineralization 9 25 9 34 Settling 9 25 9 3
33. 3 15 Loads Scale and Conversion The user has the ability to provide scale and conversion factors that can be used to attenuate or convert loading mass The conversion factor for a given system can be used to convert loads measured and reported in one unit to convert to WASP6 required units of kg day The scale factor column can be used to attenuate the loads without re entering the time function information If the user wanted to see the impacts of doubling the loads a scale factor of 2 would be entered for the desired system 3 29 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WIN WASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO File Project Pre processor Model Post Processor Help Dle g s mA EN Td a Loads Scale and Conversion Factors Scale factor Conversion factor Bere Nitrate Orthophosphate 1 00 1 00 Chlorophyl a 1 00 1 00 BOD 1 00 1 00 Dissolved Oxygen 1 00 1 00 Organic Nitrogen 1 00 1 00 Organic Phosphorous Mstart E 2 A Y B Paint Shop Pro Imeget8 s ASci WIN WASP Bl amp 10304m Figure 3 17 Waste Load Scale and Conversion Factors 3 15 1 Time Step The user is provided two options for setting the model timestep WASP has the ability to calculate its own timestep If this option is desired the user should set the appropriate flag Regardless of which ti
34. 5 Nitrification 9 25 9 3 6 Denitrification 9 26 9 4 The Dissolved Oxygen Balance 9 26 9 4 1 Benthic Water Column Interactions 9 26 9 42 Benthic Simulation 9 28 9 5 ModelImplementation_ 9 32 9 6 Simple Eutrophication Kinetics 9 33 9 6 1 Environment Parameters 9 34 9 6 2 Transport Parameters 9 34 9 6 3 Boundary Parameters 9 35 9 64 Transformation Parameters 9 36 9 7 Intermediate Eutrophication Kinetics 9 38 iv DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 9 7 Environment Parameters 9 39 9 7 2 Transport Parameters 9 39 9 7 3 Boundary Parameters 9 39 9 74 Transformation Parameters 9 40 9 8 Intermediate Eutrophication Kinetics with Benthos 1 1 9 43 10 Simple Toxicants 10 1 10 1 Simple Transformation Kinetics 10 3 10 1 1 Option 1 Total Lumped First Order Decay 10 3 10 1 2 Option 2 Individual First Order Transformation 10 4 10 2 Equilibrium Sorption 10 4 10 3 Transformations and Daughter Products 10 6 10 4 Model Implementation O 10 7 10 4 1 Model Input Parameters 10 7 10 4 2 Environment Parameters 10 7 10 4 3 Transport Parameters 10 8 10 4 4 Boundary Parameters 10 9 10 4 5 Transformation Parameters 10 10 11 Organic Chemicals 11 1
35. 9 1 2 0 6 e 8 9 04 S b 02 amp o 40 80 120 160 200 NO pg Figure 9 6 Ammonia preference The behavior of this equation for a Michaelis value Kmn of 25 ug N L is shown in Figure 5 6 The behavior of this equation is most sensitive at low values of ammonia or nitrate For a given concentration of ammonia as the available nitrate increases above approximately the Michaelis limitation the preference for ammonia reaches an asymptote Also as the concentration of available ammonia increases the plateau levels off at values closer to unity ie total preference for ammonia 9 3 2 Phytoplankton Death As phytoplankton respire and die living organic material is recycled to nonliving organic and inorganic matter For every mg of phytoplankton carbon consumed or lost ayc mg of nitrogen is released During phytoplankton respiration and death a fraction of the cellular nitrogen fon is organic while 1 fon is in the inorganic form of ammonia nitrogen The fraction recycled to the inorganic pool for Great Lakes models has been assigned at 5096 Di Toro and Matystik 1980 9 24 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 9 3 3 Mineralization Nonliving organic nitrogen must undergo mineralization or bacterial decomposition into ammonia nitrogen before utilization by phytoplankton In EUTRO the first order temperature corrected rate constant is modified by a saturated recycle term as e
36. Bowie et al 1985 and subsequently refined during the calibration and verification process This maximum growth rate constant is adjusted throughout the simulation for ambient temperature light and nutrient conditions Temperature Water temperature has a direct effect on the phytoplankton growth rate The selected maximum growth rate is temperature corrected using temporally and spatially variable water column temperatures as reported in field studies The temperature correction factor is computed using Equation 9 3 QV 20 X RTj T Ic where Eis temperature coefficient unitless Light In the natural environment the light intensity to which the phytoplankton are exposed is not uniformly at the optimum value At the surface and near surface of the air water interface photoinhibition can occur at high light intensities whereas at depths below the euphotic zone light is not available for photosynthesis due to natural and algal related turbidity 9 6 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Modeling frameworks developed by Di Toro et al 1971 and by Smith 1980 extending upon a light curve analysis formulated by Steele 1962 account for both the effects of supersaturating light intensities and light attenuation through the water column The instantaneous depth averaged growth rate reduction developed by Di Toro is presented in Equation 9 4 and is obtained by integrating the specific g
37. DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 porosities are recalculated every benthic time step If the variable bed volume is chosen upper benthic segment volumes are updated every time step with compaction occurring every benthic time step 10 4 8 Transport Parameters Number of Flow Fields Under advection the user has a choice of up to six flow fields To simulate surface water toxicant and solids transport select water column flow When simulating total solids the user should also select solids 1 flow To simulate three sediment types the user should select solids 1 flow solids 2 flow and solids 3 flow Water Column Flows ni sec Time variable water column flows can be specified as detailed in Chapter 6 2 Sediment Transport Velocities _m sec Time variable settling deposition scour and sedimentation velocities can be specified for each type of solid If the units conversion factor is set to 1 157e 5 then these velocities are input in units of m day These velocities are multiplied internally by cross sectional areas and treated as flows that carry solids and sorbed chemical between segments Settling velocities are important components of suspended sediment transport in the water column Scour and deposition velocities determine the transfer of solids and sorbed chemical between the water column and the sediment bed Sedimentation velocities represent the rate at which the bed is rising in respon
38. EA Post processor x File Edit View XY Plot Window Help Zits Curve Calculator Curve Source 0 DO at Segment 1 in EXAMPLE Predicted Line s DO at 1 in C winwasp examples example db Observed Line Calculation Type Tolerance seconds Calculation Name User Defined Jeo calcu LATED_1 User Defined Frequency Distribution Jrumpoints o CALC 1SEG TIME Data Name cae 1 VAR SNM VR d stat E A vase winawasPs BS Paint Shop Pro Image5 _ fa Post processor E Bl 10 05am Figure 4 23 Built in Curve Calculation Functions Tolerance The tolerance factor is used to sets the range of time that would consider point to be at the same time Number of Output Points Defines the number of output points that will be produced for the curve calculations Calculation Names The calculation name dialog box provides a means for the user to give a meaningful name to the calculation This is an important step because once the calculation is made to display the calculation in the x y plot the user will need to add a curve to the current or new x y plot window To do this the user would select the calculate type from the curve parameter window Once this is selected a picklist is provided of available calculations This picklist contains the calculation name as defined by the user 4 79 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Segment Time Number These dialog
39. Ea Post processor Bl amp 227m Figure 4 9 Graph Curve Attribute Screen Graph Characteristics The user has the ability to define the style of the x y plot window The user can define line types for the grid colors for the various portion of the graph and control the fonts for the various text components Once the user develops a style they have the ability to save this style to disk Each individual x y plot window can recall the style The user can define a default style that is automatically recalled every time an x y plot window is created The user specifies the title for the graph in this dialog box and can control the animation speed 4 58 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 XY Parameters Legend 0 12345 67 8 910 Figure 4 10 x y Plot Characteristics Domain Label This dialog box is used to describe the label that will be displayed below the x axis on the graph Typically the x axis is used for either time or distance 4 59 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 EN i a kar Parameters Figure 4 11 Graph Domain Labeling Primary Range Label This dialog box is used to describe the label that will be displayed above the y axis on the graph The y axis is the one on the left hand side of the graph and is typically used for concentration 4 60 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 E a
40. Help Das el en t os Preferences D x Default User Interfac C Classic WINAWASP Style Enabled Run Time Grid Always Visible ET Astart E 2 A X X Paint Shop Pio Images__ ve AScl WINAWASP ES 10254M Figure 3 3 User Preferences 3 8 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 3 6 Project Files The user can develop WASP input datasets without ever using the project file option The Project file allows the user to specify in one place all of the files that are used for a given input output file The user can create a project file by selecting New Project from the Project Menu AScl WIN WASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO File Project Pre processor Model Post Processor Help Open REE Edit Project Save Project Save Project as amp 2 AY B PaintShopPro Images AS cr WIN WASP EE 10254M Figure 3 4 WASP6 Project Menu There are three types of files that can be added to the project menu 1 WIF WASP6 input files 2 DB database files containing observed data 3 SHP ArcInfo ARCView shape files Once a project has been created the user can modify and change whenever needed When the user opens a project file the WIF file is loaded by WASP6 When the post processor is loaded the associated result file
41. NBOD data are available 4 57 before use in this model should divide values Likewise System 1 model predictions should be multiplied by 4 57 before comparison with NBOD data 8 4 1 Environment Parameters These parameters define the basic model identity including the segmentation and control the simulation Systems Select simulate for NH3 CBOD and DO and bypass for the other five systems For this implementation the NH3 system is used to represent nitrogenous BOD as expressed by TKN Segments Water column segments should be defined in the standard fashion If CBOD or NBOD settling is to be simulated the user should add a single benthic segment underlying all water column segments This benthic segment will merely act as a convenient sink for settling BOD Model calculations within this benthic segment should be ignored 8 4 2 Transport Parameters This group of parameters define the advective and dispersive transport of model variables Number of Flow Fields To simulate settling the user should select solids 1 flow under advection The user should also select water column flow 8 20 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Particulate Transport m sec Time variable settling and resuspension rates for particulate CBOD and NBOD can be input using the Solids 1 continuity array BQ and the time function QT For each solids flow field cross sectional exchange areas m for adjacent segment
42. Notation Negative log of hydrogen ion activity H pH 5 9 Negative log of ionization constants for acid pKa Negative log of ionization constants for base pK i B Enthalpy change for ionization reactions Ea 4 8 kcal mole Water temperature T 4 30 C Reference temperature Ts 20 25 C 11 9 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 11 4 Implementation The data required for the implementation of ionization in TOXI are summarized in Table 7 4 They include first identifying whether or not a particular ionic specie is to be included in the simulation and then if a particular specie is selected the information necessary to compute its formation For example to compute particular ionic specie it is necessary to input the pK negative log of the equilibrium constant for the formation of the acid and or base and the activation energy used in the Vant Hoff Equation to adjust the equilibrium constant with temperature If the activation energy is not input then no temperature correction will occur If no data are input for ionization none will occur and the reactions and transformations will be applied to the total or dissolved form of the chemical as appropriate In addition to the constants for the formation of the ionic species the pH and temperature if the rate is to be temperature corrected are required The pH and temperature are model parameters which are specified for each model segment They may be cons
43. TOXI volatilization data specifications are summarized in Table 7 8 Not all of the constants are required If Henry s Law constant is unknown it will be calculated internally from vapor pressure and solubility provided in input If Kyo is not measured it will be calculated internally from molecular weight and specified or computed liquid film transfer coefficients Volatilization is only allowed for surficial water column 11 26 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 segments as identified by the segment type specified in input The segment types are 1 Surface water segments Type 1 2 Subsurface water segments Type 2 Surficial sediment segments Type 3 and 4 subsurface sediment segments Type 4 Transformation input parameters that must be specified by the user are given below for each volatilization option Constant numbers are listed in Table 7 9 Three constants should be input for all volatilization options the volatilization option number Henry s Law Constant and the atmospheric chemical concentration Segment depths from Data Group C must be specified 2 3 2 Water body type 0 flowing 1 quiescent pcm e Multiplier for air temperature time function Volatilization option 0 none 1 measured 2 measured reaeration O Connor 3 measured reaeration MacKay 4 calculated by O Connor 5 calculated by MacK ay Henry s Law constant atm m3 mole Volatilization te
44. Use constant numbers 286 886 and 1486 for chemicals 1 2 and 3 respectively 11 41 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Measured Photolysis Rate day The user may specify the measured photolysis rate constant under reference conditions using constant KDPG Values for the neutral molecule of chemicals 1 2 and 3 can be entered using constants 291 891 and 1491 respectively Separate values can be entered for each ionic specie If a reference first order rate constant is input the quantum yield should be set to 1 0 Measured Sunlight Absorption Rate einstein mole day The user may specify measured sunlight absorption rates under reference conditions using constant KDPG Values for the neutral molecule of chemicals 1 2 and 3 can be entered using constants 291 891 and 1491 respectively Separate values can be entered for each ionic specie If a reference sunlight absorption rate is input the corresponding quantum yield must be specified Quantum Yield moles einstein The user may specify reaction quantum yield values for each phase dissolved DOC sorbed sediment sorbed and each ionic specie using constant QUANTG Constant numbers for the neutral molecule are summarized in Table 7 15 QUANTG refers to the dissolved neutral chemical QUANTG refers to the DOC sorbed neutral chemical QUANTG refers to the sediment sorbed neutral chemical Separate values can be entered for each ionic specie
45. a series of pH versus time values via PHNW and PHNS The parameter PH values will then represent the ratio of pH in each segment to the time function 11 8 Photolysis Photodegradation photolysis is the transformation or degradation of a compound that results directly from the adsorption of light energy An example of several photochemical pathways is given in 8 It is a function of the quantity and wavelength distribution of incident light the light adsorption characteristics of the compound and the efficiency at which absorbed light produces a chemical reaction Photolysis is classified into two types that are defined by the mechanism d energy absorption Direct photolysis is the result of direct absorption of photons by the toxic chemical molecule Indirect or sensitized photolysis is the result of energy transfer to the toxic chemical from some other molecule that has absorbed the radiation 11 8 1 Overview of TOXI Photolysis Reactions Photolysis is the transformation of a chemical due to absorption of light energy The first order rate coefficient for photolysis can be calculated from the absorption rate and the quantum yield for each ionic specie and phase Equation 11 62 K s 3 Vik aid if i i j where Kc first order photolysis rate coefficient at ambient light intensity day ka specific sunlight absorption rate for specie i E mole day or 11 34 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0
46. a window where the model network is color shaded based upon the predicted concentration 2 xly Plots generates an x y line plot of predicted and or observed model results in a window There is no limit on the number of x y plots spatial grids or even model result files the user can utilize in a session Separate windows are created for each spatial grid or x y plot created by the user The Graphical Post Processor is routinely executed from WASP6 Also the user can use the Windows Explorer or Run button to execute the program If executed from within WASP with an input file elected the corresponding model output files will be loaded If executed from within WASP6 without an input file selected or by some other means the user will need to use the file options for opening the files they want to display 4 1 Main Toolbar There are several toolbars and speed menus available The main tool bar is available below the pull down menus provide the following functionality to the user Depending upon the current status some icons may not be available to perform a task thus are not active Open File Icon This initiates the open file dialog box that allows the user to open a model result file BMD geometry backdrop file BMG or observed data database DB Create Spatial Animation Grid Window This opens a spatial analysis grid only after a backdrop file BMG file has been selected The user can open as many of these win
47. ambient temperature in segment C The temperature correction factors represent the increase in the biodegradation rate constants resulting from a 10 C temperature increase Values in the range of 1 5 to 2 are common 11 46 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Environmental factors other than temperature and population size can limit bacterial rates Potential reduction factors must be considered externally by the user Nutrient limitation can be important in oligotrophic environments Low concentrations of dissolved oxygen can also cause reductions in biodegradation rates and this effect is not simulated in TOXI Below DO concentrations of about 1 mg L the rates start to decrease When anoxic conditions prevail most organic substances are biodegraded more slowly Because biodegradation reactions are generally more difficult to predict than physical and chemical reactions site specific calibration becomes more important Biodegradation can be implemented using segment variable first order rate constants rather than bacterial populations If first order rate constants are input for Phac then second order rate constants kgi should be set to 1 0 in equations 7 71 and 7 72 Implementation TOXI biodegradation data specifications are summarized in Table 7 18 The second order rate constants for water and for bed segments can be specified as constants Temperature correction factors can be left at O If the us
48. as a parameter which must be specified for each model segment and may be constant or time variable Separate pH time functions may be specified for surface water and benthic segments If the user wants TOXI to adjust the rates based on temperature then non zero activation energies should be specified which would invoke the temperature based Arrhenius function Activation energies may be specified for each ionic specie and each hydrolysis reaction acid neutral base simulated If no activation energies are given then rates constants will not be adjusted to ambient water temperatures Base Hydrolysis Rate Constants M day The user may specify second order base hydrolysis rate constants for each phase dissolved DOC sorbed and sediment sorbed and each ionic specie using constant KH20 Constant numbers for the neutral molecule are summarized in Table 7 11 KH20 refers to the dissolved neutral chemical KH20 refers to the DOC sorbed neutral chemical KH20 5 1 refers to the sediment sorbed neutral chemical Neutral Hydrolysis Rate Constants day The user may specify first order neutral hydrolysis rate constants for each phase dissolved DOC sorbed and sediment sorbed and each ionic specie using constant KH20 Constant numbers for the neutral molecule are summarized in Table 7 11 KH20 5 refers to the dissolved neutral chemical KH202 refers to the DOC sorbed neutral chemical KH20 5 1 refers to the sediment sorbed neutra
49. box sets the label displayed on the graph for the segment time axis Data Name This dialog box sets the label for the value in the x y plot legend Value Expression This dialog box is used to define the function that will be performed on the values Time Expression This dialog box is used to define the function that will be performed on the time values The following tables provide information for the pre defined variables and functions that are available Pre Defined Variables Value of cell being calculated or X value of curve point being calculated Y value of curve point being calculated IR Row number 1 Number of rows of cell being calculated Returns the number of points in the reference curve I Current point number being calculated Number of seconds in a day 86400 Base of Natural Log Value of cell located at row column The largest integer not greater than the expression x C Conversion of the expression x from square feet to square meters C Conversion of the expression x from million gals day to cubic feet sec Cos of x where x is in radians 4 80 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 atural Log of x CFSGMG3LBSDAY x onverts flow cfs concentration g m3 to Lbs day CFSGM3KGDAY x onverts flow cfs concentration g m3 to kg day AQIQ QIZz es tandard Deviation of Curve z z z e value of any curve at current point value of any curve at current
50. can be substantial oxygen sinks to the overlying water column EUTRO provides two options for oxygen fluxes descriptive input and predictive calculations The first option is used for networks composed of water column segments only The kinetic equation is given in Figure 4 2 Observed sediment oxygen demand fluxes must be specified for water segments in contact with the benthic layer Seasonal changes in water temperature can affect SOD through the temperature coefficient The calculational framework incorporated for benthic water column exchange draws principally from a study of Lake Erie which incorporated sediment water column interactions performed by Di Toro and Connolly 1980 For a single benthic layer with thickness Dj the CBOD and DO mass balance equations are summarized in Figure 4 3 The equivalent SOD generated for 8 11 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 mon the overlying water column segment is also given Subscripts j and i refer to a benthic segment and the overlying water column segment respectively WASP6 allows a more detailed parameterization of settling into the benthos that includes not only a downward settling velocity but an upward resuspension velocity as well In this context then the net particulate flux to the sediment is due to the difference between the downward settling flux and the upward resuspension flux One of the first decisions to be made regarding the benth
51. can fluctuate widely and low DO concentrations in bottom waters can result Eutrophication has been modeled for approximately 30 years The equations implemented here were derived from the Potomac Eutrophication Model PEM Thomann and Fitzpatrick 1982 and are fairly standard Sections of this text are modified from the PEM documentation report 9 1 Overview of WASP6 Eutrophication The nutrient enrichment eutrophication and DO depletion processes are simulated using the EUTRO program Several physical chemical processes can affect the transport and interaction among the nutrients phytoplankton carbonaceous material and dissolved oxygen in the aquatic environment Figure 9 1 presents the principal kinetic interactions for the nutrient cycles and dissolved oxygen 9 1 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Atmosphere 02 Figure 9 1 EUTRO State Variables EUTRO can be operated by the user at various levels of complexity to simulate some or all of these variables and interactions Four levels for simulating the DO balance were described in Chapter 8 Three levels of complexity for simulating eutrophication are identified and documented at the end of this section 1 simple eutrophication kinetics 2 intermediate eutrophication kinetics and 3 intermediate eutrophication kinetics with benthos The user should become familiar with the full capabilities of EUTRO even if simpler simulations are planne
52. coefficient can be specified using constants K12C and K12T respectively Reaeration Rate day There are three basic options for specifying reaeration a single rate constant segment and time variable rate constants and flow and wind calculated rate constants These options are described in the Streeter Phelps section 8 5 Full Linear DO Balance The full DO balance equations divide the NBOD process into mineralization and nitrification and add the effects of photosynthesis and respiration from given phytoplankton levels Figure 8 6 8 22 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Benthic Sediment 1 Reaeration 2 Sediment Oxygen Demand 3 Carbonaceous Deoxygenation 4 Settling and Deposition of Particulate Organic Material 5 Nitrification 6 Mineralization 7 Photosynthesis 8 Respiration Figure 8 6 Full Linear DO Equation 8 20 2 Vs Si 7 kn M Cpe AE C D Equation 8 21 T 20 T 20 Su 7tk QO C kn90 5 Ci Equation 8 22 T 20 Se tkyOn Ci Equation 8 23 S i57 ka d Ce eT SOS 8 23 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 8 24 l 64 S 7 t k107 C Co k 4077 C s 4 k n5 Ci SOD l P Ot kite 917 rw Ore FC wee where Sx is the source sink term for variable i in a segment in mg L day Kinetic rate constants and coefficients are as defined in Table 4 1 In addition the following are used k or
53. determine its depth Two factors influence this decision The first is to adequately reflect the thickness of the active layer the depth to which the sediment is influenced by exchange with the overlying water column Secondly one wishes the model to reflect a reasonable time history or memory in the sediment layer Too thin a layer and the benthos will remember or be influenced by deposition of material that would have occurred only within the last year or two of the period being analyzed too thick a layer and the model will average too long a history not reflecting as in the case of phosphorus substantial reductions in sedimentary phosphorus resulting from reduced phosphorus discharges from sewage treatment plants The choice of sediment thickness is further complicated by spatially variable sedimentation rates The benthic layer depths together with the assigned sedimentation velocities provide for a multi year detention time or memory providing a reasonable approximation of the active layer in light of the observed pore water gradients Benthic Nitrogen The next consideration is the application of these mass balance equations to the nitrogen species in a reducing sediment Berner 1974 Particulate organic nitrogen is 9 29 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 hydrolyzed to ammonia by bacterial action within the benthos In addition to the ammonia produced by the hydrolysis of particulate organic
54. dissolved fraction in each segment Boundary Concentrations mg L At each segment boundary time variable concentrations must be specified for PHYT expressed as ug L chlorophyll a Time variable concentrations must also be specified for either ON NH3 and NO3 or OP and PO4 A boundary segment is characterized by water exchanges from outside the network including tributary inflows downstream outflows and open water dispersive exchanges Waste Loads kg day For each point source discharge time variable PHYT ON NH3 NO3 OP and PO4 loads can be specified These loads can represent municipal and industrial wastewater discharges or urban and agricultural runoff If any phytoplankton loads are specified they should be in units of kg carbon day Solids Transport Field The transport fields associated with particulate settling must be specified under initial conditions Solids 1 Field 3 is recommended for ON and OP Solids 2 Field 4 is recommended for PHYT Solids 3 Field 5 is recommended for PO4 Solid Density g cm A value of 0 can be entered for the nominal density of PHYT ON NH3 NO3 OP and PO4 This information is not used in EUTRO Initial Concentrations mg L Concentrations of PHYT expressed as ug L chlorophyll a and either ON NH3 and NO3 or OP and PO4 in each segment must be specified for the time at which the simulation begins For the nonsimulated nutrients held constant average concentrations must be spec
55. file must have the extension of HYD The hydrodynamic linkage dialog box allows the user to select a hydrodynamic linkage file The hydrodynamic linkage file provides flows volumes depths and velocities to the WASP6 model during execution There are several hydrodynamic models that have been linked with WASP6 The models include DYNHYD5 RIVMOD EFDC and SWMM s transport module When linking to a hydrodynamic interface file the user is restrained from entering additional surface flow information 3 8 Systems The system data entry form allows the user to define system specific information A system in WASP6 is a state variable within the model The state variables in WASP6 change from one model type to another The user controls which state variables will be considered in their model input dataset from within this screen 3 14 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WIN WASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO File Project Pre processor Model Post Processor Help Scale Factor 1 Ammonia F1 0000000 00 1 00 2 Nitrate E E E 0 00 0000000 00 1 00 3 Orthophosphate m E F1 0 00 D000000 00 1 00 4 Chlorophyl a Simulated mMm m m 0 00 0000000 00 1 00 5 BO0D Simulated m E m 0 00 0000000 00 1 00 B Dissolved Oxygen Simulated m E FE 0 00 0000000 00 1 00 7 Organ
56. food chain Humans may be affected by ingesting contaminated water or fish Criteria for protecting human health and indigenous aquatic communities have been promulgated for specific chemicals and for general toxicity The simulation of toxicants has become common only in the past decade Near field mixing zone models simulate the dilution and dispersal of waste plumes along with associated toxicants Far field models such as WASP6 simulate the transport and ultimate fate of chemicals throughout a water body At a minimum these models simulate the water column and a bed layer and include both chemical degradation and sorption to solids The simpler models use first order decay constants and equilibrium partition coefficients More complex models may employ second order decay mechanisms and either nonlinear sorption isotherms or first order sorption and desorption rate constants Several physical chemical processes can affect the transport and fate of toxic chemicals in the aquatic environment Some chemicals undergo a complex set of reactions while others behave in a more simplified manner WASP6 allows the simulation of a variety of processes that may affect toxic chemicals The model is designed to provide a broad framework applicable to many environmental problems and to allow the user to match the model complexity with the requirements of the problem Although the potential amount and variety of data used by WASP6 is large data requirements
57. for each rate constant k Equation 11 69 k T xk 2 k T r exp 1000 E T k T RF RT KT x where Eao Arrhenius activation energy for oxidation reaction kcal mole K Activation energies may be specified for each ionic specie simulated If no activation energies are given then rate constants will not be adjusted to ambient water temperatures 11 43 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Because of the large number of alkylperoxy radicals that potentially exist in the environment it would be impossible to obtain estimates of kox for each species Mill et al 1982 propose estimation of a rate coefficient using t butyl hydroperoxide as a model oxidizing agent They argue that other alkylperoxides exhibit similar reactivities to within an order of magnitude The second order rate coefficients are input to TOXI as constants In addition to estimating a rate coefficient an estimate of free radical concentrations must be made to completely define the expression for free radical oxidation Mill et al 1982 report RO concentrations on the order of 10 M and OH concentrations on the order of 10 M for a limited number of water bodies Zepp and Cline 1977 report an average value on the order of 10 M for singlet oxygen in water bodies sampled The source of free radicals in natural waters is photolysis of naturally occurring organic molecules If a water body is turbid or very deep free radicals are likely
58. for any particular simulation can be quite small For example it is possible to simulate a chemical using no reactions or using only sorption and one or two transformation reactions that significantly affect a particular chemical Indeed for empirical studies all chemical constants time functions and environmental parameters can be ignored and a simple user specified transformation rate constant used Thus WASP6 can be used as a first order water pollutant model to conduct simulations of dye tracers salinity intrusion or coliform die off Table 10 1 Overview of Simple WASP6 Toxicants SYSTEM VARIABLE CHEMICAL 1 SOLIDS 3 sors 6 CHEMICAL3 10 1 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Simple toxicants and associated solids are simulated using the TOXI program TOXI simulates the transport and transformation of one to three chemicals and one to three types of particulate material solids classes Table 10 1 The three chemicals may be independent or they may be linked with reaction yields such as a parent compound daughter product sequence The simulation of solids is described in Chapter 3 The simulation of simple toxicants is described below The simulation of more complex organic chemicals is described in Chapter 11 In an aquatic environment toxic chemicals may be transferred between phases and may be degraded by any of a number of chemical and biological processes Simplified t
59. form to that developed by Smith which is also available as an option in this model Equation 9 6 Xn Q o Let K D cet y K D I I e Ss Ss where Equation 9 7 I t 5 p vl t 0 f 0 t f 1 and Equation 9 8 k ic X rr O i Dmx K ef where L the time variable incident light intensity just below the surface assumed to follow a half sin function over daylight hours ly day O max the quantum yield mg carbon fixed per mole of light quanta absorbed K the extinction coefficient per unit of chlorophyll m2 mg chlorophyll a K the light extinction coefficient computed from the sum of the non algal light attenuation K and the phytoplankton self shading attenuation K a as calculated by Equation 5 9 m 9 8 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 9 9 K esna Ke P crn f units conversion factor 0 083 assuming 43 incident light is visible and 1 mole photons is equivalent to 52 000 cal mole photons m ly E the ratio of carbon to chlorophyll in the phytoplankton mg carbon mg chlorophyll a e the base of natural logarithms 2 71828 unitless Equations 9 6 9 9 give a light limitation coefficient that varies over the day with incident light This term is numerically integrated over the day within the computer program to obtain daily average light limitation Equation 9 10 1 X r xe t dt o The term ks the temperat
60. function is not yet available This typically means that some prerequisite was not met yet b This icon instructs the program to initiate a new file This icon allows the retrieval of a previously created model input file or project file n m This saves the active file to disk Note that Save as is available from the File Menu structure This toggles the input definition icons on off 3 5 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 i This executes the appropriate model based upon the currently loaded input file Q This icon is only available when the model is actually running The user can abort the model simulation by pressing this icon NOTE It may take several minutes for the model to abort N This loads the graphical post processor If the user has a project or model input file selected this information is passed to the post processor ES Model Parameterization at Mogel Time Step Definition Screen Page 3 31 Model Simulation Result Interval Page 3 32 Model Segment Definition Screen Page 3 17 Model System Definition Page 3 15 Segment Parameter Scale Factors Page 3 23 Model Kinetic Constant Definition Page 3 35 Waste Load Time Series Definition Page 3 29 Environmental Time Series Definition Page 3 33 DReFMARC BE Dispersion Data Entry Page 3 24 EXC Flow Data Entry Page 3 26 Boundary Condition Time Series Page 3 28 3 Input Dataset Validity Check Page 3 3
61. high speed WASP eutrophication and organic chemical model processors and 4 a graphical post processor for the viewing of WASP results and comparison to observed field data Because of the architecture utilized in the design of WASP6 it is going to be relatively easy to develop other kinetic modules for WASP Currently we are planning on the development of an enhanced eutrophication model that will include the addition of the following state variables 2 additional algal groups salinity full heat balance coliforms second BOD group sediment digenesis model 1 1 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 2 Acknowledgements The US EPA would like to acknowledge the generous donation that ASci Corporation has made by releasing the Windows of WASP to EPA and the public domain Their realization of the environmental good that will come from the use of this model and their unselfish attitude should be commended Furthermore the authors would like to recognize Mr Jim Greenfield EPA Region 4 for his support and encouragement in the development and enhancement of WASP6 The authors would like to express gratitude to Mr Mohammed Lahlomo for his support and efforts in bringing WASP6 to the public domain 2 2 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 3 Introduction The Water Quality Analysis Simulation Program WASP6 an enhancement of the original WASP Di Toro et al 1983 Co
62. i Solids 1 13H Solids 2 1316 Solids 3 1321 This option allows the user to directly input constant partition coefficients that apply over the entire model network These partition coefficients are input using the set of constants PIXC in units of L kg not in log units If only one chemical and one solids type is being simulated then the partition coefficient can be input by specifying a value for Constant 111 PIXC 1 1 All other partitioning information should be omitted i e LKOW LKOC and FOC If three chemicals are being simulated the user may specify values for their partition coefficients to solids 1 using three separate PIXC values Constants 111 711 and 1311 respectively If multiple solids types are being simulated then separate partition coefficients may be input for each of the three solids types The constant partition coefficients for chemical 1 to solids type 2 and 3 can be input by specifying appropriate PIXC values for Constants 116 and 121 respectively Constant numbers for partitioning of chemical i to solid j are summarized in Table 6 4 Option 2 Spatially Variable Partition Coefficients This option allows the user to directly input spatially variable partition coefficients for chemical 1 These partition coefficients are input using the parameter FOC in units of L kg not in log units If only one chemical and one solids type is being simulated then the partition coefficients can be input by s
63. in TOXI The user is referred to Chapter 3 for a summary of input parameters for the sediment balance equations Input parameters are prepared for WASP6 in four major sections of the preprocessor environment transport boundaries and transformation Basic model parameters are described in Chapter 2 and will not be repeated here 10 4 2 Environment Parameters These parameters define the basic model identity including the segmentation and control the simulation Systems To simulate a toxicant select simulate for chemical 1 and bypass for chemical 2 and chemical 3 To simulate total solids along with the toxicant select simulate for solids 1 and bypass for solids 2 and solids 3 To simulate two or more toxicants or solids select simulate for the appropriate variable Bed Volume Option The user must determine whether bed volumes are to be held constant or allowed to vary Volumes may be held constant by specifying 0 in which case sediment concentrations and porosities in the bed segments will vary Alternatively sediment concentrations and porosities may be held constant by specifying 1 in which case surficial bed segment volumes will vary Bed Time Step While mass transport calculations are repeated every model time step certain benthic calculations are repeated only at this benthic time step in days If the constant bed volume option is chosen sediment concentrations are updated every model time step but 10 7
64. is given a dialog box that contains a list of all the loaded layers the user can select which one to 4 54 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 display by using standards Windows selection methods Once a layer has been added to the selected dialog window the user can control the order in which the layer is drawn by moving the layer up and down in the window The model network should be the last layers to be drawn to make sure that another layer does not over write it Select All This will select all of the loaded layers Once they are selected the user should press the Add Button Select None De selects any selected layers Move Up Down The move up down button will move the selected highlighted layer up in down in the list The layers at the top of the list are drawn first Layer Color The user has the ability select a specific color for a given layer Because the GIS layers do not have a color associated the post processor assigns a color This assignment may not be desirable to change the layer color select the layer and press the layer color button The user will be presented a color selection dialog box Select the color and press Okay 4 3 15 GIS Toolbar The GIS toolbar has a couple of additional buttons that are not found on non GIS spatial analysis view i This button will save the GIS view to a bitmap file The user is presented a conventional file dialog box gl This co
65. is proportional to the gradient between the dissolved concentration and the concentration in the overlying atmosphere and the conductivity across the interface of the two fluids The conductivity is influenced by both chemical properties molecular weight Henrys Law constant and environmental conditions at the air water interface turbulence controlled by wind speed current velocity and water depth 11 19 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 11 6 1 Overview of TOXI Volatilization The dissolved concentration attempts to equilibrate with the gas phase concentration as illustrated in 8 and given by Equation 11 40 9C E c Du ee D d H RT x where the transfer rate m day D segment depth m fi fraction of the total chemical that is dissolved Ci atmospheric concentration ug L R T universal gas constant 8 206x10 atm m mole K water temperature K Henry s law coefficient for the airwater partitioning of the chemical atm m mole Equilibrium occurs when the dissolved concentration equals the partial pressure divided by Henry s Law Constant In TOXI the dissolved concentration of a chemical in a surface water column segment can volatilize at a rate determined by the two layer resistance model Whitman 1923 The two resistance method assumes that two stagnant films are bounded on either side by well mixed compartments Concentration differences serve as the dri
66. j in solid phase s In TOXI it is convenient to define concentration related symbols as in Table 10 2 Please note that in the general development of the equations below subscripts i and j are sometimes omitted for convenience 10 1 Simple Transformation Kinetics TOXI allows the user to specify simple first order reaction rates for the transformation reactions of each of the chemicals simulated First order rates may be applied to the total chemical and varied by segment Alternatively constant first order rates may be specified for particular processes including biodegradation hydrolysis photolysis volatilization and oxidation These constant rates may be used exclusively or in combination with model computed rates as described in Chapter 11 For example the user may specify a first order rate for biodegradation and have TOXI compute a loss rate for volatilization 10 1 1 Option 1 Total Lumped First Order Decay The simplest rate expression allowed by TOXI is lumped first order decay This option allows the user to specify spatially variable first order decay rate constants day for each of the chemicals simulated Because these are lumped decay reactions chemical transformations to daughter products are not simulated Equation 10 1 C Ot reaction _ K ij Ci where K lumped first order decay constants day for chemical i in segment j The lumped decay rate constant is a model parameter that may be
67. nitrogen in the benthos ammonia is generated by the anaerobic decomposition of algae In a study of this reaction Foree and McCarty 1970 showed that the anaerobic rate of decay of algae is substantial 0 007 0 022 day However the end product initially is not exclusively ammonia Rather a fraction of the algal nitrogen becomes particulate organic nitrogen which must undergo hydrolysis before becoming ammonia Ammonia produced by the hydrolysis of nom algal organic nitrogen and the decomposition of detrital algal nitrogen may then be exchanged with the overlying water column via diffusion No nitrification occurs in the sediment due to the anaerobic conditions present in the sediment Denitrification the conversion of nitrate to nitrogen gas may occur however Nitrate is present in the benthos due to diffusive exchange with the overlying water column The analysis of the benthic nitrogen concentrations and the resulting flux of ammonia is relatively straightforward because of the simplicity of the kinetics hydrolysis and anaerobic algal decay produce a stable end product ammonia which does not undergo further reactions in the anaerobic sediment The equations resulting from the above framework are presented in Figure 9 8 and the coefficients are summarized in Table 6 1 Benthic Phosphorus A complete analysis of the phosphorus fluxes from sediments would require a rather complex and elaborate computation of solute precipitate chemistry
68. of particle concentration This model was shown to be in conformity with observations for a large set of adsorption desorption data At present this should be considered an empirical relationship The equation defining partition coefficient 1s Equation 11 39 K ps0 Dias en ee i I M K po V where AZ e e limiting partition coefficient with no particle interaction f o for neutral organic chemicals solids concentration kg L ratio of adsorption to particle induced desorption rate Z n IOA il Qo zi 11 16 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Di Toro found that 6 was of order 1 over a broad range of chemical and solids types This formulation has been included in TOXI If 6x is specified to be 1 0 then TOXI will predict a maximum particulate fraction in the water column of 0 5 for all hydrophobic chemicals KpsoMs gt 10 Implementation Common SI Range Units D escription Notation Suspended sediment concentration m 10 100 mg L Benthic sediment concentration Mp 0 5 2 kg L Dissolved organic carbon DOC B 0 10 mg L Partition coefficient Kyi 101 105 L kg phasei Lumped metal distribution coefficient Kp 100 105 L kg Octanol water partition coefficient Kow 100 106 Organic carbon fraction phase i foci 0 005 0 5 Particle interaction parameter Ox 1 102 xow 9 594 a Solids independent limiting partition coefficient to solids 1 Solids independent
69. out of i This option allows for the lateral transport of sediment across the upper bed and can be used to represent bed load transport The Variable Bed Volume Option The second bed volume option referred to as the variable bed volume option allows bed volumes to change in response to deposition and scour Two types of bed layers are assumed an upper uncompacted layer and one or more lower compacted layers When deposition exceeds scour the upper layer increases in volume as the surface of the bed rises After a period of time the added volume of upper bed compresses and becomes part of the lower bed When scour exceeds deposition the volume of the upper layer decreases as the surface of the bed drops When the upper layer erodes completely the next layer of bed is exposed to scour In locations where sediment deposition exceeds scour Figure 7 2 bed compaction is triggered by a sedimentation time step This sedimentation time step is input by the user and will generally be much larger than the simulation time step As sediment and sorbed chemical settle from the water column the top bed segment increases in volume sediment mass and chemical mass Sediment concentrations remain constant The volume of the upper bed continues to increase until the end of the sedimentation time step At this time the volume of the upper bed 7 6 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 that has been added by net deposition i
70. output file use the variable drop down picklist and select the variable you want the spatial analysis grid to display EA Post processor EXAMPLE Segment Depth m at 17171985 0 00 iej x es File Edit View GIS Window Help 81 xl ee Spatial Plot Parameters r Data Data Set EXAMPLE Ivi Time m Varying Parameter 11 1985 0 00 x Time Variable C Variable Segment Depth m x Segment Depth m Temperature C Wind Speed m sec ede le Ren Select All Standar ile IAS Select None E Program Smee GR S aada l _SelectNone Move Up Move Down Color T Display Labels Cancel lt e j eed zz i a im CAPS NUM OVR CZ 5 Basco WINAVASP E Post processor EX 8 Paint Shop Pro Image15 Bl amp s54M Figure 4 6 Selecting Variable to Display Note The spatial analysis grid can only display one result variable at a time 4 52 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 4 3 9 Selecting Time The spatial analysis grid displays results for a given variable at a given time Not only does the user have the ability to control the display of variables but can control the display time as well The user can select what simulation time to display the results for a given variable This pull down picklist allows the user to move the spatial analysis grid to specific points in time without steppi
71. point Number of Points in Curve value of any curve at any point value of any curve at any point nterpolates the value of curve c at domain value x Sum of the values in the curve ME n Frequency Running Average These are built in calculations They work much the same as the user defined with the exception the user does not have to enter any functions they are done automatically Once this dialog box has been completed and the user has pressed the Okay button this partition calculation can now be plotted To plot the partition calculation the user should press the Add Curve button The curve parameter dialog box will appear The user should select the Calculate radio button Once Calculate is selected the user should see the name of the calculation just performed appear in the file dialog box The user can then select the variable and location to plot Once these are selected and the user presses Okay the x y plot window will re appear with the calculated data plotted as well 4 81 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 5 The Basic Water Quality Model WASP6 is a dynamic compartment model that can be used to analyze a variety of water quality problems in such diverse water bodies as ponds streams lakes reservoirs rivers estuaries and coastal waters This section presents an overview of the basic water quality model Subsequent chapters detail the transport and transformation pro
72. pollutant conductivity can be estimated The input computed volatilization rate constant is for a temperature of 20 C It is adjusted for segment temperature using the equation Equation 11 42 K r K 20 9 7 where E temperature correction factor 11 21 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 T water temperature C Directly input volatilization rates are not temperature adjusted Computation of the Transfer Rates There have been a variety of methods proposed to compute the liquid Ki and gas phase Ko transfer coefficients several of which are included in TOXI The particular method to be employed is identified by the model through the user s selection of one of six volatilization options each of which is briefly described below 11 6 2 Volatilization Option 1 This option allows the use of measured volatilization rates The rates Ky m day are input as a parameter which may be varied by segments and may be time variable 11 6 3 Volatilization Option 2 This option allows the user to input an oxygen reaeration constant that is then adjusted to represent the liquid film transfer constant for the particular chemical The adjustment is made in one of two ways First the user may input a measured ratio of oxygen to chemical exchange so that the rate KL is computed from Equation 11 43 K Kat K wo where E reaeration velocity m day Kv ratio of volatilization rate to rea
73. rates and by these solids transport rates In WASPSO solids transport rates in the water column and the bed are input via up to three solids transport fields as described in Chapter 3 The transport of the particulate fraction of organic chemicals follows the solids flows The user must specify the dissolved fraction i e 0 0 and the solids transport field for each simulated solid under initial conditions To simulate total solids solids 1 must be used 11 2 4 Model Input Parameters Input parameters are prepared for WASP6 in four major sections of the preprocessor environment transport boundaries and transformation The organic chemical input parameters comprising the first three sections are identical to those in the simple toxicant model The user is referred to Section 6 2 for a summary of these input parameters This section and the rest of this chapter describes the organic chemical reaction parameters 11 2 2 Transformation Parameters This group of parameters includes spatially variable parameters constants and kinetic time functions for the water quality constituents being simulated The organic chemical reactions and model input parameters are described in individual sections below Because water temperature can affect every chemical reaction it is described here 11 4 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Water Temperature C Water temperature can vary in space and time affecting
74. single rate constant segment and time variable rate constants and flow and wind calculated rate constants These options are described in Section 4 2 under the Streeter Phelps transformation parameters CBOD Deoxygenation Rate day The CBOD deoxygenation rate constant and temperature coefficient can be specified using constants KDC and KDT respectively The half saturation constant for oxygen limitation of carbonaceous deoxygenation can be specified using constant KBOD The default value for KBOD is 0 0 indicating no oxygen limitation 9 8 Intermediate Eutrophication Kinetics with Benthos Simulating benthic interactions requires the addition of benthic segments to the model network All state variables are simulated in the benthic segments Dissolved fractions of NH3 NO3 PO4 CBOD DO ON and OP may exchange with the water column by diffusion Particulate fractions of PHYT PO4 CBOD ON and OP may deposit to or be scoured from the benthic segments Benthic layer decomposition rates for OP ON PHYT and CBOD must be specified 9 43 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 The equations used are those presented in Figure 8 4 and Figure 9 8 Rate parameters are summarized in Table 8 2 and Table 9 6 Many of the environment transport boundary and transformation parameters required to implement this option are the same as those in the intermediate eutrophication option presented above The benthic nitr
75. specific file format containing specifically named data fields Calculated The user created the calculated field using built in functions One such function is the model partition function where the user can calculate the difference between one curve and another The results of this calculation are stored in a user defined Calculated data structure Selecting Data File The selection of the data source radio buttons will determine the content of the data file dialog window If a model simulation result file is loaded and the Predicted radio button is selected the filenames will appear in the Predicted Data window The user selects the file to obtain plotting information from by pressing the left mouse button on the filename The selected file will become highlighted Once the file has been selected the user needs to select the variable and segment from which to retrieve information for plotting Selecting Variable The variable list that is displayed in the variables dialog window is taken directly from the selected file If it is a model simulation result file it will contain the output variables of either the hydrodynamic or water quality model 4 65 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 If the selected file is an observed data database the variables are the names of stored constituents in the database If the selected file was a calculated data structure the name of the variable will be that assigne
76. summarized in Table 7 19 KBIO20 refers to the dissolved neutral chemical KBIO20 refers to the DOC sorbed neutral chemical KBIO20 refers to the sediment sorbed neutral chemical Temperature Coefficients The user may specify temperature correction factors for the dissolved DOC sorbed and sediment sorbed phase of each chemical using constants Q1ODIS Q102DOC and QIOPAR respectively These constants represent the multiplication factor for biodegradation rates corresponding to a 10 C temperature increase Constant numbers are summarized in Table 7 19 If Q10 values are omitted or set to 0 biodegradation rates will not be affected by temperature Bacterial Population Levels cell mL The user may specify segment and time variable bacterial concentrations using parameter 14 BAC and time funcions 16 and 17 BACNW and BACNS Typical population size ranges are given in Table 7 19 If bacterial concentrations are to remain constant in time the user should enter segment mean concentrations using parameter BAC BACNW and BACNS should be omitted Bacterial Numbers Water Body Type cells ml Ref Oligotrophic Lake 50 300 a Mesotrophic Lake 450 1 400 a Eurtophic Lake 2000 12 000 a Eutrophic Reservoir 1000 58 000 a Dystrophic Lake 400 2 300 a Lake Surficial Sediments 8x10 5x1010 a cells 100 g dry wt 40 Surface Waters 500 1x106 b Stream Sediments 107 108 C cells 100 g Rur River winter 3x104 d References We
77. the contents A description for each of the icons on the spatial grid toolbar are given below 4 46 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Configure Animation Grid This button allows the user to access the spatial grid configuration screen where the user can select what backdrop file and model data will be displayed Step Animation Grid Forward One Time Interval This button causes the active spatial grid to step forward one time interval in the model result file Step Animation Grid Back One Time Interval This button causes the active spatial grid to step backward one time interval in the model result file Plays animation sequence forward in time Plays animation sequence backward in time Exi 4 3 3 Geographical Information System Interface The graphical post processor has the ability to display ArcView shape files with the model network being one of the layers To use this option the user must have access to GIS coverage s and a copy of ArcView The post processor can display any number of coverage s the shape files must be loaded using the file open option or be contained in the project file Before a model network can be displayed the user must develop a coverage and related database using the ArcView program Creating Coverages To create a coverage the user will need to rely on a good understanding of ESRI s ArcView ArcInfo programs The model network will need to be added as a layer
78. the equation used varies with the velocity and depth of the segment First the transfer coefficient for dissolved oxygen is computed using the formulations provided below and then Ky calculated from equation 7 44 or 7 45 For segments with depths less than 0 61 m the Owens formula is used to calculate the oxygen reaeration rate Equation 11 45 0 67 je Karo gei where u D For segments with a velocity less than 0 518 m s or a depth m greater than 13 584 u the O Connor Dobbins formula is used velocity of the water m s segment depth m Equation 11 46 0 5 wit ri B 8 64 e 10 11 23 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 where Dw is the diffusivity of the chemical in water m s computed from Equation 11 47 _ 22 10 B M w In all other cases the Churchill formula is used to calculate reaeration rate Equation 11 48 0 969 u K 5900 TT The gas transfer coefficient Kc is assumed constant at 100 m day for flowing systems b Stagnant Lake or Pond For a stagnant system type 1 the transfer coefficients are controlled by wind induced turbulence For stagnant systems the liquid film transfer coefficient Ki is computed using the O Connor equations Equation 11 49 Uo 0 33 K D u Pa us S cw iid p 2 Equation 11 50 K Ko u SCa Aa 0 67 where u is the shear velocity m s computed from Equation 11 51 u E d W io whe
79. the rates of all chemical reactions Time and segment variable water temperatures can be specified using the parameters TEMP and TMPEN and the time functions TEMPN 1 4 If temperatures are to remain constant in time then the user should enter segment temperatures using the parameter TEMP TMPEN and TEMPN 1 4 should be omitted If the user wants to enter time variable temperatures then values for the parameter TEMP should be set to 1 0 The parameter TMPEN indicates which temperature function will be used by the model for each segment Values of 1 0 2 0 3 0 or 4 0 will call time functions TEMPN 1 TEMPN 2 TEMPN 3 and TEMPN 4 respectively Water temperatures should then be entered via these time functions as a series of temperature versus time values The product of TEMP and the selected TEMPN function will give the segment and time specific water temperatures used by TOXI TEMP and TMPEN are identified in TOXI as parameters 3 and 2 respectively TTEMPN 1 4 are identified in TOXI as time functions 4 Group G Record 4 PARAM L3 PARAM L2 Group I Record 2 VALT 1 4 K Notation In TOXI it is convenient to define concentration related symbols as in Table 7 3 Please note that in the general development of the equations in the sections below subscripts i and j are sometimes omitted for convenience Symbol D efinition Units Ci Concentration of total chemical i in segmentj mge L Cwij Concentration of dissolved che
80. the user to create a table of the data that is represented in the current x y plot Pressing the data table icon on the x y plot toolbar creates this table This will cause the creation of a table of data as illustrated in Figure 4 21 The data in this table is read only This basically means the user can access the data by marking columns and rows of data and copying it to the Windows clipboard so that it can be pasted into another application i e spreadsheet EI Es EN Post processor File Edit View XY Plot Window Help EA Tampa Bay Table E Domy gt 1 1 1 1985 0 00 00 7 00 B 1671985 0 00 00 7 72 m 1571985 0 00 00 7 12 7 1985 0 00 00 7 14 71671965 0 00 00 MESE 6 1985 0 00 00 6 81 5 1985 0 00 00 10 87 10 39 14 1985 0 00 00 9 91 1985 0 00 00 8 02 1985 0 00 00 8 05 1985 0 00 00 8 01 w s i 0 1985 1986 1987 1988 1989 ALAL ABA z TEE 3 CAPS NUM OVR MStan E 77 9 we asc winawasr BS Paint Shop Pro Image2 _ fa Post processor Bl 10034M Figure 4 21 Example of Tabular Data from Graph The user has no ability to modify the data and have the results appear in the x y plot Exporting Data The user may export the data that is used to generate the active x y plot to an external file to 1 comma delimited ASCII files and 2 Paradox database files 4 76 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 The comma delimited ASCII fi
81. to 1 0 The parameter TMPEN indicates which temperature function will be used by the model for each segment Values of 1 0 2 0 3 0 or 4 0 will call time functions TEMP 1 TEMP 2 TEMP 3 and TEMP 4 respectively Water temperatures should hen be entered via these time functions as a series of temperature versus time values The product of TMPSG and the selected TEMP function will give the segment and time specific water temperatures used by EUTRO TMPSG and TMPFN are identified in EUTRO as parameters 3 and 4 respectively TEMP 1 4 are identified in EUTRO as time functions 1 4 Solar Radiation langleys day Time variable solar radiation at the water surface can be described using time functions ITOT and FDAY Seasonally varying values of solar radiation at the surface can be entered using ITOT with a series of radiation versus time values FDAY gives the seasonally varying fraction of day that is daylight entered as a series of fraction versus time values Internally EUTRO uses the quotient ITOT FDAY for the average radiation intensity during daylight hours Light Extinction m Time and segment variable light extinction coefficients can be specified using the parameters KESG and KEFN and the time functions KE 1 5 If extinction coefficients are to remain constant in time then the user should enter segment coefficients using the parameter KESG KEEN and KE 1 4 should be omitted 9 36 DRAFT Water Quality Analysis Simulation Prog
82. to be generated only near the air water interface and consequently chemical oxidation will be relatively less important In such cases the concentrations cited above are appropriate in only the near surface zones of water bodies The molar oxidant concentrations are input to TOXI using parameter OXRADG ISEG Implementation D escription Notation Range Units Oxidation rate constant for specie i phase j Koij L mole day Activation energy for oxidation of specie i E aoi 15 25 kcal mole K Water temperature T 4 30 oC Concentration of oxidants RO 2 1017 108 moles L TOXI oxidation data specifications are summarized in Table 7 16 The water temperature and concentration of oxidants are input parameters which may be specified for each model segment The temperature may be time variable as well input as a time series If an activation energy is not supplied no temperature corrections will be performed Input data are described below VARIABLE C2 TREFO 858 1458 KOX20n 861 1461 KOX 202 866 1466 KOX2031 871 1471 876 1476 Oxidation Rate L mole day The user may specify second order oxidation rate constants for each phase dissolved DOC sorbed and sediment sorbed and each ionic specie using constant KOX20 Constant numbers for the neutral molecule are summarized in Table 7 17 KOX20 refers to the dissolved neutral chemical KOX20 refers to the DOC sorbed neutral chemical KOX203 refers to the sediment sorbed neutral chemical
83. wind speed and air temperature are 0 6 m sec and 15 C The scale of the water body should be input using constant WTYPE Values of 1 0 2 0 and 3 0 indicate laboratory scale lake and reservoir scale and open ocean scale respectively The default value is 2 For estuaries where salinity affects DO saturation significantly salinity values in g L can be input using parameter SAL and time function SALFN The product of spatially variable SAL 8 17 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 and time variable SALFN gives the segment and time specific salinity values used by EUTRO Average segment salinity values can be input to SAL while relative variations in time if significant can be input to SALEN For northern climates where ice cover can affect reaeration during winter months the user may input the fraction of water surface available for reaeration using time function XICECVR A value of 1 0 indicates that the entire surface area is available for reaeration The time variable value of XICECVR will be multiplied by the reaeration rate constants for options 1 and 3 For option 2 it is assumed that ice cover is built into the time function REAR WTYPE and K2 are identified in EUTRO as constants VELEN SAL and REARSG are identified in EUTRO as parameters WIND VELN 1 4 SALEN AIRTMP XICECVR and REAR are identified in EUTRO as time functions 8 4 Modified Streeter Phelps The modified Streeter Phelps e
84. 0 231 126 741 0 34 5 290 0 0 215 120 6 95 0 34 6 292 5 0 194 115 6 73 0 34 7 295 0 0 174 109 6 52 0 34 8 297 5 0 157 106 6 30 0 34 9 300 0 0 141 101 6 12 0 34 10 302 5 0 133 95 5 94 0 34 11 305 0 0 126 90 5 76 0 34 12 307 5 0 119 85 5 57 0 34 13 310 0 0 105 80 5 39 0 34 14 312 5 0 0994 78 5 22 0 34 15 315 0 0 0952 75 5 06 0 34 16 317 5 0 0903 72 4 90 0 34 17 320 0 0 0844 70 4 74 0 34 18 323 1 0 0793 68 4 56 0 34 19 330 0 0 0678 64 4 7 0 34 20 340 0 0 0561 59 3 64 0 34 21 350 0 0 0463 55 3 15 0 34 22 360 0 0 0379 55 2 74 0 34 23 370 0 0 0300 51 2 34 0 34 Specific Light Extinction Coefficients Pure Water Chlorophyll DOC Solids Number Wavelen lm L gm m L mgm L mgm 24 380 0 0 0220 46 2 00 0 34 25 390 0 0 0191 42 1 64 0 34 26 400 0 0 0171 41 1 39 0 34 27 410 0 0 0162 39 1 19 0 34 28 420 0 0 0153 38 1 02 0 34 29 430 0 0 0144 35 0 870 0 34 11 36 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Specific Light Extinction Coefficients Pure Water Chlorophyll DOC Solids Number Wavelength lm L gm m L mgm L mgm 1 280 0 0 288 145 7 90 0 34 30 440 0 0 0145 32 0 753 0 34 31 450 0 0 0145 31 0 654 0 34 32 460 0 0 0156 28 0 573 0 34 33 470 0 0 0156 26 0 504 0 34 34 480 0 0 0176 24 0 444 0 34 35 490 0 0 0196 22 0 396 0 34 36 503 75 0 0295 19 0 357 0 34 37 525 0 0 0492 14 0 282 0 34 38 550 0 0 0638 10 0 228 0 34 39 575 0 0 0940 8 0 188 0 34 40 600 0 0 244 6 0 158 0 34 Al 625 0 0 314 5 0 0 0 34 42 650 0 0 349 8 0 0 0 34
85. 09 Number 9 pp 731 752 Paris D F W C Steen G L Baughman and J T Barnett Jr 1981 Second Order Model to Predict Microbial Degradation of Organic Compounds in Natural Waters Applied and Environmental Microbiology 4 3 603 609 Rao S S 1976 Observations on Bacteriological Conditions in the Upper Great Lakes 1968 1974 Scientific Series No 64 Inland Waters Directorate CCIW Branch Burlington Ontario 12 4 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Rao P S C and J M Davidson 1980 Estimation of Pesticide Retention and Transformation Parameters Required in Nonpoint Source Pollution Models Environmental Impact of Nonpoint Source Pollution Ann Arbor Science Ann Arbor MI pp 23 67 Riley G A H Stommel and D F Bumpus 1949 Quantitative Ecology of the Plankton of the Western North Atlantic Bull Bingham Oceanog Coll 12 3 1 169 Robinson N ed 1966 Solar Radiation Elsevier Publishing Amsterdam London and New York 347 pp Smith R A 1980 The Theoretical Basis for Estimating Phytoplankton Production and Specific Growth Rate from Chlorophyll Light and Temperature Data Ecological Modeling 10 pp 243 264 Steele J H 1962 Environmental Control of Photosynthesis in the Sea Limnol Oceanogr 7 137 150 Streeter H W and E B Phelps 1925 A Study of the Pollution and Natural Purification of the Ohio River IIL Factors Concerned in the Phenomena of Oxidation and
86. 0W j Ji J wj where Vw Py T D 2 3 1 2 m renis De a E er K Zo Pw Vw 1 2 TERM2 Be Pa Se or Equation 8 7 1 2 86400 2s p v Je 7717 d kw 100 D K ze Py Vw where wind induced reaeration rate coefficient day time varying wind speed at 10 cm above surface m sec air temperature C density of air a function of T g cm density of water 1 0 g cm viscosity of air a function of T cm s viscosity of water a function of T cm s diffusivity of oxygen in water a function of T cm s von Karman s coefficient 0 4 eae or ij o ow on wy Ow lo 1 v transitional shear velocity set to 9 10 and 10 for small medium and large scales cm s V critical shear velocity set to 22 11 and 11 for small medium and large scales cm s and large scales cm Z effective roughness a function of z A Cu Vy Va and W cm Z equivalent roughness set to 0 25 0 35 and 0 35 for small medium inverse of Reynold s number set to 10 3 and 3 for small medium 8 6 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 and large scales A nondimensional coefficient set to 10 6 5 and 5 for small medium and large scales A nondimensional coefficient a function of A v Ca and W C drag coefficient a function of z A v v and W Equation 8 5 is used for wind speeds of up to 6 m sec where interfacial conditions are smooth and vis
87. 11 1 TOXIReactions and Transformations 0 0 11 3 11 2 ModelImplementation_ 11 4 11 2 1 Model Input Parameters 11 4 11 2 2 Transformation Parameters 11 4 11 3 Tonization_ 2 2 000 00222 11 6 11 3 1 Overview of TOXI Ionization Reactions 11 6 11 4 Implementation 1 11 1 1 LL 11 10 11 5 Equilibrium Sorption 11 11 11 5 1 Overview of TOXI Sorption Reactions 11 12 11 5 2 Comp utation of Partition Coefficients 11 15 11 5 3 Option Measured Partition Coefficients 11 15 11 5 4 Option 2 Input of Organic Carbon Partition Coefficient 11 15 11 5 5 Option 4 Computation of Solids Dependant Partitioning 11 16 11 5 6 Option 1 Measured Partition Coefficients 11 18 11 5 7 Option 2 Input of Organic Carbon Partition Coefficient 11 18 11 5 8 Option 3 Computation of the Organic Carbon Partition Coefficient 11 18 11 5 9 Option 4 Solids Dependant Partitioning 11 19 11 6 Volatilization _______ 00 000 000 0000 11 19 11 6 1 Overview of TOXI Volatilization 11 20 11 62 Volatilization Option 1 11 22 11 6 3 Volatilization Option 2 11 22 11 6 4 Volatilization Option 3 11 23 11 6 5 Volatilization Option 4 11 23 11 6 6 Volatilization Option 5 11 25 11 6 7 Volatilization Option 1 11 28 11 6 8 Volatilization Option 2 11 28 11 6 9 Volatilization Option 3 11 29 11 6 10 Volatilization Option 4 11 29 11 6 11 Volatilization Option 5 11 30 DRAFT Water Quality Analysis Simulation Program WASP 11 7 Hydrolysi
88. 205 oaeo 537012 Conso Gn oase 3005 422 70073 126 g 77853 Conso omz nae 24980 a525 7069 asso oos samos Cona oos7 zxy 12076 19239 some osia onaz e1472 01114 0 0158 0 1115 0 5642 1 0630 7 2981 0 4009 0 0153 66 2420 0 0898 0 0102 0 1069 0 9035 1 1026 7 5761 0 3943 0 0178 1 9053 eu Er Em E 1 bn Em mi E ME ia EF Begin Execution of WASP EF Getting Model ParameterizationD ata EE Getting Dispersion Information EE Getting Segment Volumes Information EE Getting Flow Information EE Getting Time Variable Boundary Information EE Getting Time Variable Loadings EF Getting Segment Specific Environmental Conditions EF Getting Kinetic Constants EF Getting Environmental Time Functions EF Getting Initial Conditions we Time Loom Cimulahian Sharad Figure 3 28 WASP6 Runtime Grid 3 41 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 4 Visual Graphic Post Processor The Post Processor was developed as an efficient means of processing the vast amount of data produced by the execution of the WASP6 models It has the ability to display results from all the models EUTRO and TOXTI included in the WASP6 modeling package The Post Processor reads the output files created by the models and displays the results in two graphical formats 1 Spatial Grid a two dimensional rendition of the model network is displayed in
89. 3 10 Segment Parameter Scale Factors This screen defines which parameters will be considered in the simulation as well as specifying a parameter scale factor By default the scale factor is 1 0 Before an environmental segment parameter will be considered by WASP6 the used box must be checked Un checking this box will remove the parameter from the simulation but all entered information is not lost An example of using this feature is looking at the influence of SOD on dissolved oxygen Make the first simulation with the SOD parameter checked make the next run with it un checked The differences between the two runs are the influence of SOD The user can also change the scale factors for each parameter For example if you wanted to double SOD set the scale factor to 2 0 3 22 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WIN WASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO File Project Pre processor Model Post Processor Help Use Scale Factor m 1 00 Ixi 1 00 Temperature of Segment X 1 00 Temperature Time Function for Segment X 1 00 Light Extinction for Segment Ix 1 00 Light Extinction Time Function to use for l 1 00 Benthic Ammonia Flux g m2 Ki 1 00 Benthic Phosphate Flux g m2 Ix 1 00 Sediment Oxygen Demand g m2 Xi 1 35 Sediment Oxygen Demand Temperature X 1 10 Incoming Solar Radiat
90. 43 675 0 0 440 13 0 0 0 34 44 706 25 0 768 3 0 0 0 34 45 750 0 2 47 2 0 0 0 34 46 800 0 2 07 0 0 0 0 34 Ly is calculated for each wavelength based upon the time of year latitude ground elevation cloud cover air mass type relative humidity atmospheric turbidity and ozone content The atmospheric characteristics can vary monthly or be specified as an annual average The value of d the ratio of the optical path to the vertical depth is difficult to compute but a probable best value is 1 19 Hutchinson 1967 However in the presence of a large concentration of scattering particles it may approach 2 0 In order to ensure that an improper value is not loaded and used in computations the input value is checked and set to 1 19 if the input is invalid The photolysis rate constants for each water column segment are determined from the calculated near surface rate constant and the rate of light decay in the water column Ke The value of Ke is calculated for each wavelength based on a formulation taken from EXAMS II Equation 11 65 K K wtN CHL n DOC n m where K ww pure water extinction coefficient 1 m CHL phytoplankton chlorophyll concentration mg L DOC dissolved organic carbon concentration mg L m solids concentration mg L 1 2 3 specific extinction coefficients L mg m 11 37 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Values of Kew cl 2 3 for each of the 46 wavelengths a
91. 9 3 6 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 3 5 File Menu Because WASP has changed the methods in which model input data is stored the user may have to import old datasets in the new framework Old WASP input files had an extension of INP which stood for input file These old style input files were ASCII formatted files that could be read by most word processors and utility text editors WASP still stores the model input data in individual files but now they have the extension WIF WASP input file The new style input file is binary which allows for rapid saving retrieving of information The preprocessor can only view this file in a meaningful manner WASP6 also supports a Project File format where the user can provide other WASP6 related files Project files are edited from the project menu item AScl WIN AWASP Standard a x File WIN WASP Help Look in Cd winwasp El al ek BE File name ftampa Files of type WIN WASP Projects WWP Cancel start E 2 A X Paint Shop Pio Imaget__ re AScl WINAWASP Bl amp 10254m Figure 3 2 File Dialog Menu 3 5 1 Importing Old WASP Input Files If you have previous version of WASP input files you can import them into the new file structure For an old file to be successfully imported into the new structure the file must be a valid WASP input file one that is read by the DOS version of WASP and produ
92. B CO ERPS NUM OVR AMStart SS A Y se iN wAsPe 9 Faint Shop Pro E Post processor Bl 10024M Figure 4 1 File Dialog Box BMD Format To open a WASP simulation result file select binary model data from the file type box This will cause the file dialog box to display only those files that have the extension BMD The user has the ability to move around between drives and directories to select a file to review The user can either double click the mouse on the desired file or highlight the file and press the open button Once the file is open the x y plot icon will become available Note The user must load a binary model geometry file BMG before the spatial grid analysis icon is available BMG File BMG files are used to provide spatial analysis grid geometry information hese files are specific to model input datasets 1e BMG files must correspond to information in the 4 44 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 BMD files BMG files are created using a utility program called Digitize The file must be created prior to execution The BMG file is selected in the same manner as the other files by setting the file type to BMG and selecting the file Note The user must load a binary model geometry file BMG before the spatial grid analysis icon is available Observed Data The observed data is in a Paradox 4 5 or higher format DB In order to display observed d
93. C and K12T respectively The half saturation constant for oxygen limitation of nitrification can be specified using constant KNIT The default value for KNIT is 0 0 indicating no oxygen limitation Denitrification Rate day The denitrification rate constant and temperature coefficient for dissolved nitrate nitrogen can be specified using constants K20C and K20T respectively The half saturation constant for oxygen limitation of denitrification can be specified using constant KNO3 The default value for KNO3 is 0 0 indicating no denitrification at oxygen concentrations above 0 0 Benthic Nitrogen Flux mg m day The segment and time variable benthic nitrogen flux can be specified using parameter FNH4 and time function TFNH4 The product of the spatially variable FNH4 and time variable TFNH4 gives the segment and time specific benthic flux for NH3 used by EUTRO Flux versus time values can be entered using TFNHA while unitless segment ratios can be entered using FNH4 Values should be entered for water column segments that are in contact with the bottom of the water body Sediment Oxygen Demand g m day Segment variable sediment oxygen demand fluxes and temperature coefficients can be specified using the parameters SODID and SODTA respectively Values should be entered for water column segments that are in contact with the bottom of the water body Reaeration Rate day There are three basic options for specifying reaeration a
94. Calculations This icon brings up the curve calculation dialog box The user can perform data transformation on the data or use one of the predefined functions Create Data Table from Graph This creates a table of data represented by the lines in the graph window The user will be able to review the data and copy data from the table to programs like spreadsheets Toggle graph window between color and black amp white Because some printers do not transpose the color to black and white effectively this option allows the user to force black amp white or color Causes re draw of the plot window E EE 4 4 3 Creating x y Plot The first time that the x y plot icon button requesting a x y plot is pressed the graph configuration menu appears It is from this menu that the user has control over the content of 4 57 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 the x y plot window The user can plot data within this x y window for any or all of the currently loaded files simulation result files or observed data The user has full control over the appearance of graph axis title and legend labeling E Post processor x File View Window Help Curves General Domain Primary Range Secondary Range Curve Attributes Data Representation Miscellaneous Predicted data C PROGRAM FILESSASCI gment 2 DO Saturation Sa EIE CAPS NUM OVA MStart E A X Pant Shop Pro Images
95. E L mole L day j reaction quantum yield for specie i in phase j mole E i fraction of chemical as specie i in phase j The user may specify that the model calculate the first order photolysis rate constant or the user may provide a near water surface rate for presumed cloudless conditions If the user supplied rate constant is representative of conditions at a location other than the water body being modeled the model corrects the rate for the difference in latitude between the two and any difference in cloud cover The options for computing the losses due to photolysis are briefly described below 11 8 2 Photolysis Option 1 Under this option the photolysis rate is calculated from molar absorptivities calculated light intensity and quantum yield of the chemical To calculate the rate constant TOXI divides the wavelength spectrum between 280 and 800 nm into 46 intervals For each interval the user must specify a molar absorptivity The light intensity at each of the 46 wavelengths is internally calculated from the location of the water body ie latitude the time of year and the atmospheric conditions air mass type relative humidity atmospheric turbidity and ozone content cloudiness The location and time of year are used to define the light intensity at the outer edge of the atmosphere The atmospheric conditions are used to define the light decay through the atmosphere The light intensities and the molar absorptivities are u
96. Getting Model ParameterizationD ata ES Getting Dispersion Information EG Information Tito Astar eu if X9 Paint Shop Pro Image24 aset WIN WASP ES 10 324M Figure 3 27 Model Data Retrieval Once the model is executed WASP6 provides information back to the user on where it is in the simulation The first set of information is the status of the data retrieval from the preprocessor WASP6 does not read the conventional input files from the previous versions of WASP6 and WASP it makes requests to the preprocessor for the information as it is needed Depending upon the size of your model network and amount of time variable data this set can take some time Once the model data has been retrieved it will begin the simulation Once the simulation has started a grid will appear on the screen this grid contains intermediate results for each of the state variables for each of the segments The user can scroll this grid to look at the results The user can shrink or stretch a column by dragging the column boundary in out 3 40 Version 6 0 DRAFT Water Quality Analysis Simulation Program WASP AScl WIN WASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO Cas lta QUE Bel en ios 9 lK l n aoa ooo osas s42 roam 759 20 01355 aerez Comcs ooms oso esa asm rar iss 01222 aces 0 5173 3 5489 01305 oos 01277 aoso Case anor rae 1
97. I First chemical concentrations should be near trace levels i e below half the solubility or 10 molar At higher concentrations the assumptions of linear partitioning and transformation begin to break down Chemical density may become important particularly near the source such as in a spill Large concentrations can affect key environmental characteristics such as pH or bacterial populations thus altering transformation rates Table 10 2 Concentration related symbols used in mathematical equations Symbol Definition Units Cj Concentration of total chemical i in segment j mgd L Cwij Concentration of dissolved chemical i in segment j mgd L C wij Concentration of dissolved chemical i in water in segment j C wi Cwi nj mgd Lw Cai Concentration of sorbed chemical i on sediment type s in segment j mgd L C sj Concentration of sorbed chemical i on sediment type s in segment j mgv kgs 10 2 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 symbol Definition Units Cj Caj Msj mg Concentration of sediment type s in segment j mgd L Mj Concentration of sediment type s in segment j Mj mj 106 kgs L M s Concentration of sediment type s in water in segment j kgs Lw nj Porosity or volume water per volume segment j Lw L K psj Partition coefficient of chemical i on sediment type s in segment j Lw kgs fpi Fraction of chemical i in segment j in dissolved phase fs Fraction of chemical i in segment
98. Link Node Hydrodynamic Linkage with WASP The hydrodynamic model calculates flow through the links and volume within the nodes Within the hydrodynamic model the user must specify the water quality time step or the number of hydrodynamic time steps per water quality time step The hydrodynamic model must then write out node volumes at the beginning of each water quality time step and average link flows during each water quality time step The user in the hydrodynamic model or in an external interface program must supply a network map such as the one in Figure 6 1 This map is used to create a hydrodynamic file that WASP6 can read and interpret The hydrodynamic model DYNHYDS supplied with WASPS contains subroutines to produce a proper WASP6 hydrodynamic file It is important to note that the hydrodynamic model has additional nodes outside of the WASP6 network These additional nodes correspond to WASP6 boundaries denoted by nominal segment number 0 These extra hydrodynamic nodes are necessary because while flows are calculated only within the hydrodynamic network WASPO requires boundary flows from outside its network Multidimensional hydrodynamic models can also be linked to WASP6 A compatible two dimensional network is illustrated in Figure 2 2 For the beginning of each water quality time step the volumes within a WASP6 segment must be summed and written to the hydrodynamic file For the duration of each water quality time step flows acr
99. Program WASP Version 6 0 E Segments Segment Ammonia Nivete Othophoaphate Chiorophyia BoD 2 emo omo 54 1209 295 3 eum om 049 1209 2046 O a amm omw 049 1500 2945 S ammo omo 54 1509 209 0 1500 0 0100 0 4000 15 0000 2 0000 8 amm omw 54 zoo 29 9 omo o um cat Figure 3 10 Segment Initial Concentrations 3 9 4 Fraction Dissolved In addition to chemical concentrations the dissolved fractions at the beginning of the simulation must be specified for each segment For tracers the dissolved fractions will normally be set to 1 0 For tracers as well as dissolved oxygen eutrophication and sediment transport the initial dissolved fractions remain constant throughout the simulation For contaminants the fraction dissolved is recomputed based upon user specified partitioning relationships 3 21 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WIN WASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTROJ File Project Pre processor Model Post Processor Help Segments Segments Parameters Initial Concentrations Fraction Dissolved 1 0000 Qo yn Dn 4 wi nO e Fil Calc PMstart E 2 A X 8 Paint Shop Pro Imege2 s ASci WIN WASP Bl amp 10254M Figure 3 11 Fraction Dissolved for Constituents
100. RAFT Water Quality Analysis Simulation Program WASP Version 6 0 Particulate Transport m sec Time variable settling and resuspension rates for particulate CBOD and ON can be input using the Solids 1 continuity array BQ and the time function QT For each solids flow field cross sectional exchange areas m for adjacent segment pairs are input using the spatially variable BQ Time variable settling velocities can be specified as a series of velocities in m sec versus time If the units conversion factor is set to 1 157e 5 then these velocities are input in units of m day These velocities are multiplied internally by cross sectional areas and treated as flows that carry particulate organic matter out of the water column 8 5 3 Boundary Parameters This group of parameters includes boundary concentrations waste loads and initial conditions Boundary concentrations must be specified for any segment receiving flow inputs outputs or exchanges Initial conditions include not only initial concentrations but also the density and solids transport field for each solid and the dissolved fraction in each segment Boundary Concentrations mg L At each segment boundary time variable concentrations must be specified for NH3 NO3 ON CBOD and DO A boundary segment is characterized by water exchanges from outside the network including tributary inflows downstream outflows and open water dispersive exchanges Waste Loads kg day For e
101. S G aging Stations Average of 10 G aging Stations on Rhine River Ephemeral Streams in Semiarid U S Table 6 2 compares hydraulic exponents for a rectangular channel with data reported by Leopold et al 1964 Note that the average velocity exponent is relatively constant for all channel cross sections The major variation occurs as a decrease in the depth exponent and concomitant increase in the width exponent as channel cross sections change from the steep side slopes characteristic of cohesive soils to the shallow slopes of arid regions with noncohesive soils For bodies of water such as ponds lakes and reservoirs velocity and depth may not be a function of flow For these cases both the velocity and depth exponents b and d can be chosen to be zero 0 00 Because Q to the zero power is equal to one 1 0 the coefficients a and c must be the velocity and depth i e IF b 0 0 THEN a V and IF d 2 0 0 THEN c D When the depth exponent is zero WASP6 will adjust segment depths with segment volumes assuming rectangular sides For site specific river or stream simulations hydraulic coefficients and exponents must be estimated Brown and Barnwell 1987 recommended estimating the exponents b and d and then calibrating the coefficients a and c to observed velocity and depth The exponents may be chosen based on observations of channel shape noted in a reconnaissance survey If cross sections are largely rectangular with vertic
102. SP6 pore water flows are input via transport field two Pore water advection transports water and dissolved chemical sediment and particulate chemical are not transported The mass derivative of chemical due to pore water flow from segment j to segment 1 is given by Equation 6 8 OM Sr QafuCafn where M mass of chemical k in segment i g C total concentration of chemical k in segment j mg L g m n porosity of segment j L L fy dissolved fraction of chemical in segment j Q pore water flow rate from j to i m day Dissolved fractions fp may be input by the user in Figure 3 11 In TOXI these are recomputed from sorption kinetics each time step WASPO tracks each separate pore water inflow through the benthic network For each inflow or outflow the user must supply a continuity function and a time function The actual flow through benthic segments that results from each inflow is a product of the tme function and the continuity function If a flow originates in or empties into a surface water segment then a corresponding surface water flow function must be described in flow field 1 that matches the pore water function 6 2 4 Water Column Dispersion Dispersive water column exchanges significantly influence the transport of dissolved and particulate pollutants in such water bodies as lakes reservoirs and estuaries Even in rivers longitudinal dispersion can be the most important process diluting peak conce
103. Sorbed chemical 11 3 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 migrates downward or upward through net sedimentation or erosion Both rate constants and equilibrium coefficients must be estimated in most toxic chemical studies Although these can be calculated internally from chemical properties and local environmental characteristics site specific calibration or testing is desirable Some limitations should be kept in mind when applying TOXI First chemical concentrations should be near trace levels ie below half the solubility or 10 molar At higher concentrations the assumptions of linear partitioning and transformation begin to break down Chemical density may become important particularly near the source such as in a spill Large concentrations can affect key environmental characteristics such as pH or bacterial populations thus altering transformation rates TOXI does not include such feedback phenomena 11 2 Model Implementation To simulate organic chemicals with WASP6 use the preprocessor or text editor to create a TOXI input file The model input dataset and the input parameters will be similar to those for the conservative tracer model as described in Chapter 2 To those basic parameters the user will add benthic segments solids transport rates and transformation parameters During the simulation solids and organic chemicals will be transported both by the water column advection and dispersion
104. TEMP 1 4 If temperatures are to remain constant in time then the user should enter segment temperatures using the parameter TMPSG TMPEN and TEMP 1 4 should be omitted If the user wants to enter time variable temperatures then values for the parameter TMPSG should be set to 1 0 The parameter TMPEN indicates which temperature function will be used by the model for each segment Values of 1 0 2 0 3 0 or 4 0 will call time functions TEMP 1 TEMP 2 TEMP 3 and TEMP 4 respectively Water temperatures should then be entered via these time functions as a series of temperature versus time values The product of TMPSG and the selected TEMP function will give the segment and time specific water temperatures used by EUTRO TMPSG and TMPEN are identified in EUTRO as parameters 3 and 4 respectively TEMP 1 4 are identified in EUTRO as time functions 1 4 Sediment Oxygen Demand g m day Segment variable sediment oxygen demand fluxes and temperature coefficients can be specified using the parameters SODID and SODTA respectively Values should be entered for water column segments that are in contact with the bottom of the water body If temperatures remain constant in time then SODTA can be omitted CBOD Doeoxygenation Rate day The CBOD deoxygenation rate constant and temperature coefficient can be specified using constants KDC and KDT respectively NBOD Deoxygenation Rate day The NBOD deoxygenation rate constant and temperature
105. The dissolved fraction of PHYT should be set to 0 and the dissolved fraction of DO should be set to 1 Only the particulate fractions of CBOD and the nutrients will be subject to settling 9 7 4 Transformation Parameters This group of parameters includes spatially variable parameters constants and kinetic time functions for the water quality constituents being simulated Parameter values are entered for each segment Specified values for constants apply over the entire network for the whole simulation Kinetic time functions are composed of a series of values versus time in days Water Temperature C Time and segment variable water temperatures can be specified using the parameters TMPSG and TMPFN and the time functions TEMP 1 4 as described in the simple eutrophication section above Solar Radiation langleys day Time variable solar radiation at the water surface can be described using time functions ITOT and FDAY as described in the simple eutrophication section above Light Extinction m Time and segment variable light extinction coefficients can be specified using the parameters KESG and KEFN and the time functions KE 1 5 as described in the simple eutrophication section above 9 40 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Growth Rate day The maximum phytoplankton growth rate constant and temperature coefficient can be input using constants KIC and KIT respectively Carbon to Chloro
106. Water Quality Analysis Simulation Program WASP Version 6 0 DRAFT User s Manual By Tim A Wool Robert B Ambrose James L Martin Edward A Comer US Environmental Protection Agency Region 4 Atlanta GA Environmental Research Laboratory Athens GA USACE Waterways Experiment Station Vicksburg MS Tetra Tech Inc Atlanta GA DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Table of Contents 1 Forward 1 1 2 Acknowledgements 2 2 3 Introduction 3 3 3 1 Overview of the WASP6 Modeling System o 3 3 3 2 Installation 5S5 ooo ir t So E s 3 5 3 3 TechnicalSupport 1 3 5 3 4 ToolBarDefiniion 3 5 Se MleM n 5c ome velo cL omes ss ems 3 7 3 5 1 Importing Old WASP Input Files 3 7 3 52 Exporting Old WASP Input Files 3 8 3 5 3 User Preferences 3 8 3 6 Project Files 2 2 5 e ac eot od Ar 3 9 3 6 1 New 3 9 3 62 Open 3 10 3 63 Edit 3 10 3 6 4 Save 3 10 3 65 Save as 3 10 3 7 Input Parameterization 1 1 0 1 3 11 3 7 1 Data Set Description 3 12 3772 Model Type 3 12 3 7 3 Comments 3 12 3 7 4 Restart Options 3 13 3 7 5 Date and Times 3 13 3 7 6 Non Point Source File 3 13 3 7 7 Hydrodynamics 3 13 98S OV SUMING 4 A ek 0 d 8 8 rA 3 14 3 8 1 System Options 3 15 3 82 Disp
107. a flowing waterbody the turbulence is primarily a 11 25 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 function of the stream velocity while for stagnant waterbodies wind shear may dominate The formulations used to compute the transfer coefficients vary with the waterbody type as shown below a Flowing Stream River or Estuary The liquid and gas film transfer coefficients for flowing waterbodies are computed identically to those described under Option 4 b Stagnant Pond or Lake Under this option the liquid and gas film transfer coefficients are computed using formulations described by Mackay and Yeun 1983 The Mackay equations are Equation 11 55 K 710 0 00341u Sc u 3m s Equation 11 56 K 10 0 0144y Sc y 3m s Equation 11 57 K 6710 0 0462 u Se Implementation Description Notation Range Units Measured or calibrated conductance Ky 0 6 25 m day Henry s Law Constant H 107 101 atm m mole Concentration of chemical in atmosphere Ca 0 1000 pg L Molecular weight Mw 10 103 g mole Reaeration coefficient conductance of Ka 0 6 25 m day oxygen Experimentally measured ratio Of Kw 0 1 volatilization to reaeration Current velocity Ux 0 2 m sec Water depth D 0 1 10 m Water temperature T 4 30 C Wind speed 10 m above surface Wio 0 20 m sec Although there are many calculations involved in determining volatilization most are performed internally using a small set of data
108. ace Flow field upper left table go over to the flow function table upper ght table and press insert The bottom tables are a function of the selection in the upper tables Segment Pairs The segment pairs define the segments from to which flow occurs The order in which the segment is defined should be the path of positive flow In other words if segment 1 flows to segment 2 when a negative flow is entered in the time function the flow will be from 2 to 1 Note Neither preprocessor nor the model makes any checks to make sure the segments are connected in any manner Connectivity is the responsibility of the user Fraction of Flow The fraction of flow column allows the user to specify the fraction of the flow that transports from one to segment to the other This field is used to split flows diverge for various reasons 3 12 2 Flow Time Function The time function table allows the user to enter time variable flow information The user must provide the date time and flow cms 3 13 Boundaries Boundary concentrations must be specified for any segment receiving flow inputs outputs or exchanges from outside the model network The boundary segments are automatically determined by WASP6 when the user defined the transport patterns Therefore the user cannot enter boundary information until the transport information has been entered WASP6 requires that a boundary concentration be specified for every system that is being simulate
109. ach point source discharge time variable NH3 NO3 ON CBOD and DO loads can be specified These loads can represent municipal and industrial wastewater discharges or urban and agricultural runoff Solids Transport Field The transport field associated with particulate CBOD and ON settling must be specified under initial conditions Field 3 is recommended for both Solid Density g c P A value of 0 can be entered for the nominal density of NH3 NO3 ON CBOD and DO This information is not used in EUTRO Initial Concentrations mg L Concentrations of NH3 NO3 ON CBOD and DO in each segment must be specified for the time at which the simulation begins Average concentrations of PHYT expressed as ug L chlorophyll a must be specified as well These are converted to mg L phytoplankton carbon in EUTRO using a default carbon to chlorophyll ration of 30 Phytoplankton concentrations will remain constant throughout the simulation and affect DO through photosynthesis and respiration Concentrations of zero for non simulated variables PO4 and OP will be entered by the preprocessor Dissolved Fraction The dissolved fraction of NH3 NO3 ON CBOD and DO in each segment must be specified Values for DO should be 1 0 Only the particulate fraction of CBOD and ON will be subject to settling 8 25 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 8 5 4 Transformation Parameters This group of parameters includes s
110. ack amp White This radio button selection works the same as if the user pressed the Color Black amp White icon from the toolbar This will toggle the x y plot between color and black amp white Curve Definition The curves dialog window indicates how many lines are currently defined for the given graph To add a curve to the gaph the user should press the Add Curve button This will bring up the curve definition window If the user wants to edit the attributes of a previously created curve the user should select the curve to be edited in the curve window 4 63 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 by clicking the mouse pointer on the curve and press edit curve There is no limit to the number of curves that can be defined for a given x y plot Okay Cancel The Okay Cancel button determines what state the user wants to leave the form If anything was modified in the plot parameter screen and the user selects Okay the x y plot window will be updated with the newly entered selected information If the user selects Cancel any entered information would be lost and the x y plot window would remained unchanged Curve Attributes Adding a Curve If the Add Curve button is pressed in the graph configuration menu a second dialog box appears to define the attributes of the curve Defining those attributes will result is a single curve being added to the x y plot lel xi E Post processor File View Wind
111. al analysis grid can be displayed a BMG file needs to be created This file is created using a utility program called Digitize Digitize allows the user to draw the model network or the portion of the model network on the screen and assign cross section numbers to polygons that they represent There is a one to one correspondence to polygons that are drawn with a cross section in the model BMD file Routine Execution of Digitize The Digitize program is a DOS based program Because Digitize needs access to the computers communication ports and uses its own communication drivers the program cannot be executed within the Windows environment Digitize needs to be executed from the Windows Command Prompt option To start Windows in the command prompt mode restart your Windows system When the Starting Windows string appears on the screen press the F8 key and select command prompt To execute Digitize change directory to where the WASP6 modeling environment has been installed Digitize parameters digfile The last step in creating the BMG file is linking all of the various slices into one BMG file The BMG file is created using a program called Digilink 4 48 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Developing a Spatial Grid The spatial grid file BMG is a specially created file that provides geometric information This geometric information is generated using the Digitize program The Digitize program has two type
112. al banks the first set of exponents shown should be useful If channels have steep banks typical of areas with cohesive soils then the second set of exponents is appropriate If the stream is in an arid region with typically noncohesive soils and shallow sloping banks then the last set of exponents is recommended The key property of the channel that should be noted in a reconnaissance survey is the condition of the bank slopes or the extent to which width would increase with increasing stream flow Clearly the bank slopes and material in contact with the stream flow at the flow rate s of interest are the main characteristics to note in a reconnaissance This gives general guidance but it should be noted that values are derived for bankful flows Even in streams with vertical banks the low flows may be in contact with a sand bed having shallow sloped almost nonexistent banks more representative of ephemeral streams in semi arid areas 6 6 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 6 2 3 Pore Water Advection Pore water flows into or out of the bed can significantly influence benthic pollutant concentrations Depending on the direction of these flows and the source of the pollutants pore water advection may be a source or sink of pollutants for the overlying water column If benthic segments are included in the model network the user may specify advective transport of dissolved chemicals in the pore water In WA
113. an be entered using constant numbers 63 74 the annual average can be entered using number 75 Dissolved Organic Carbon mg L The user may specify segment variable dissolved organic carbon concentrations using parameter 6 DOC Group G Record 4 PARAM I 6 Chlorophyll a mg L Time and segment variable phytoplankton chlorophyll a concentrations can be specified using parameter 10 CHPHL and time function 14 CHLN If chlorophyll concentrations are to remain constant in time the user should enter segment mean concentrations using parameter CHPHL CHLN should be omitted The user may enter time variable chlorophyll a concentrations via time function CHLN as a series of concentration versus time values Parameter CHPHL will then represent the ratio of each segment concentration to the time function values The product of CHPHL and the CHLN function gives the segment and time specific chlorophyll concentrations used by TOXI Group G Record 4 PARAM I 10 Group I Record 2 VALT 14 K 11 8 5 Photolysis Option 2 In option 2 TOXI extrapolates either observed sunlight absorption rates or photolytic decay rates under reference conditions to ambient conditions Required input data are described below Photolysis Option The user should select the photolysis option using constant XPHOTO 0 no photolysis 1 photolysis rates will be computed from molar absorptivity 2 photolysis rates will be extrapolated from measured surface rates
114. an increase in the resolution of the input data 5 5 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 FREQUENCY DISTRIBUTION OF OBSERVED AND CALCULATED VALUES OF A QUALITY VARIABLE OBSERVED TIME SCALE 2 TIME SCALE1 STEADY STATE WATER QUALITY VARIABLE 5 50 95 CUMULATIVE PROBABILITY Figure 5 4 Frequency Distribution of Observed and Calculated Values of a Quality Variable Once the nature of the problem has been determined then the temporal variability of the water body and input loadings must be considered Generally the model time step must be somewhat less than the period of variation of the important driving variables In some cases this restriction can be relaxed by averaging the input over its period of variation For example phytoplankton growth is driven by sunlight which varies diurnally Most eutrophication models however average the light input over a day allowing time steps on the order of a day Care must be taken so that important non linear interactions do not get averaged out When two or more important driving variables have a similar period of variation then averaging may not be possible One example is the seasonal variability of light temperature nutrient input and transport in lakes subject to eutrophication Another example involves discontinuous batch discharges Such an input into a large lake might safely be averaged over a day or week because large scale transport variations
115. and its interaction with the mass transport of the dissolved species The reasons for this are twofold first it is well known Nriagu 1972 that for phosphorus the Hrmation of precipitates affects the interstitial water concentrations thereby affecting the interstitial water transport of the various phosphorus forms or species second the dissolved concentrations are affected by the redox reactions which in turn affect the phosphorus fluxes that occur during aerobic and anaerobic conditions Phosphorus fluxes are enhanced under anaerobic conditions A computation of solute precipitate chemistry was judged to be outside the scope of this model Instead a simplified approach was taken which to a large degree relies on empiricism Anaerobic decomposition of detrital algal phosphorus is assumed to occur using the same rate expressions and rate constants as those for detrital algal nitrogen yielding both organic and inorganic phosphorus Anaerobic decomposition of organic phosphorus then proceeds lt A spatially variable fraction of the end product dissolved inorganic phosphorus remains in the interstitial water and is not involved in the formation of precipitates and is not sorbed onto the benthic solids This spatial variation reflects the ionic chemical makeup of the benthos in various regions of the water body Using observed total and interstitial dissolved inorganic phosphorus values the fraction dissolved inorganic phosphorus can be assi
116. ange Function Time value pairs for Surface Water Exchange Function Value Date Time IE 12 25 2014 12 00AM 23E 1 fi Wasp Seg 2 Wasp Segmen 32609 0000 5029 0000 Pi Insert 7 Delete El Fil Cat Pi Insert 7 Delete X Cancel Fi Cak E ee N Astar amp HA ll X9 Paint Shop Pro Image20 aset WIN WASP B 10314M Figure 3 13 Dispersion Entry Forms 3 11 1 X Exchange Fields This table in the upper left portion of the screen allows the user to define dispersion for two types of exchanges To use one of these exchange fields you must check the Use box and enter a scale and conversion factor When the use box is unchecked the information for the particular exchange field is not passed to the model during execution 1 Surface Water Exchange The exchange of both dissolved and particulate fraction 2 Pore Water Exchange This exchange field moves only the dissolved portion of a constituent 3 11 2 Dispersion Function For each of the exchange fields the user can define up to 10 exchange functions Each exchange function can have its own set of exchange segment pairs and a corresponding dispersion time function WASP6 allows the user to provide names for each of the exchange functions To add an exchange function click on the insert button To delete a function select the function by highlighting the row and click on the delete button This 3 24 DRAFT
117. ankton population is small but does not permit the rate to increase continuously as phytoplankton increase The assumption is that at higher population levels recycle kinetics proceed at the maximum first order rate The default value for Kmpc is 0 which causes mineralization to proceed at its first order rate at all phytoplankton levels 9 2 4 Sorption There is an adsorption desorption interaction between dissolved inorganic phosphorus and suspended particulate matter in the water column The subsequent settling of the suspended solids together with the sorbed inorganic phosphorus can act as a significant loss mechanism in the water column and is a source of phosphorus to the sediment Because the rates of reaction 9 18 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 for adsorption desorption are in the order of minutes versus reaction rates in the order of days for the biological kinetics an equilibrium assumption can be made This equilibrium reaction implies that the dissolved and particulate phosphorus phases instantaneously react to any discharge sources of phosphorus or runoff or shoreline erosion of solids so as to redistribute the phosphorus to its equilibrium dissolved and solids phase concentrations Consider Cprp to be the concentration of dissolved inorganic phosphorus in the water column It interacts with the particulate concentration Cprp The interaction may be an adsorption desorption process wi
118. are relatively infrequent he same batch input into a tidal estuary cannot safely be averaged however because of the semi diurnal or diurnal tidal variations A third example is salinity intrusion in estuaries Tidal variations in flow volume and dispersion can interact so that accurate long term predictions require explicit simulation at time steps on the order of hours Once the temporal variability has been determined then the spatial variability of the water body must be considered Generally the important spatial characteristics must be homogeneous within a segment In some cases this restriction can be relaxed by judicious averaging over width depth and or length For example depth governs the impact of reaeration and sediment oxygen demand in a column of water Nevertheless averaging the depth across a river would generally be acceptable in a conventional waste 5 6 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 load allocation whereas averaging the depth across a lake would not generally be acceptable Other important spatial characteristics to consider depending upon the problem being analyzed include temperature light penetration velocity pH benthic characteristics or fluxes and sediment concentrations The expected spatial variability of the water quality concentrations also affects the segment sizes The user must determine how much averaging of the concentration gradients is acceptable Becau
119. ata versus the predicted model results the database must be in a specific form To load an observed data database follow the procedures described above change the file type to DB Select the database and press open Note The observed data database is expected to be in a certain file format with pre defined field names 4 3 Spatial Graphical Analysis The spatial graphical analysis allows the user to review model results for the whole network for a given constituent and time This mode of graphical representation of the model results is very effective in illustrating model predictions to non technical audiences 4 3 1 Overview The spatial graphical analysis function allows the user to illustrate the model results on a spatial grid using shading to represent predicted values There are two options for creating spatial analysis grids The first option allows the user to develop a binary model geometry file BMG to illustrate a portion of the modeling network or the complete network The BMG is developed specifically for a particular model dataset with corresponding assignments for each of the model computational elements that are to be displayed In other words the BMG has polygons that are to be shaded based upon the predicted concentration of the model computational elements assigned to the polygons by the user at the time the BMG file is created The spatial grid analysis provides three modes for looking at the model results
120. atabase The user has several options available for creating the observed data database If the user has Paradox they can use it to create the observed data database If the user does not have Paradox the user is provided the option of creating an observed data database If the user elects to create the observed data database in Paradox there are four important fields that the database must contain 1 DateTime this field is of type Timestamp It is used to store the date amp time of the observed data point 2 PCODE this field is of type alphanumeric It is used to describe the type of measurement being stored i e Dissolved Oxygen 3 STATION ID this field is of type alphanumeric lt is used to describe the sample station identification 4 RESULT this field is of type numeric It is used to describe the measured value of PCODE at time DATETIME at STATION ID The four fields above have to be defined exactly as described to be useful Any variance from what is given above and the file will not be recognized The observed data database can contain more than the four fields described above but at a minimum must contain these fields To create a new observed data database the user should press the Create New Database icon on the main toolbar This will cause a new observed data database table to be generated that the user can populate with their own data Figure 4 20 illustrates a newly created observed data database table Th
121. ates Equation 6 11 Vi S Bik o te C Bik where Sai boundary loading rate response of chemical k in segment d Li g m day V a of boundary segment i m Qa lt upstream inflow into boundary TTT i m day At downstream boundary segments WASP6 applies the following mass s rates 6 9 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 6 12 Vi SBT Q O t e Cir where Qi downstream outflow from boundary segment i m day C internal concentration of chemical k in segment i mg L Notice that the specified boundary concentration is not used to calculate the boundary loading rate for the downstream boundary segment If however the downstream outflow becomes negative it becomes in reality an inflow In this case Equation 6 11 applies where Qoi Qio At exchange boundary segments WASP6 applies the following mass loading rates Equation 6 13 EF io t A y s Ent t Anto Ca ci0 where terms are as defined above When a boundary concentration exceeds the internal concentration mass is added to the boundary segment when the boundary concentration falls below the internal concentration mass is lost from the boundary segment 6 2 7 Loading Processes WASP6 allows the user to specify loading rates for each variable Two types of loadings are provided for point source loads and runoff loads The user in the input dataset specifies the first set of loads The seco
122. ation charts or from a series of transects measuring depth versus width along the river Sometimes volumes can be estimated from the travel time of a well mixed cloud of dye through a reach For simulations using hydrodynamic results volumes from the hydrodynamic summary file HYD are used and continuity is maintained Figure 3 8 6 4 2 Transport Parameters This group of parameters defines the advective and dispersive transport of simulated model variables Input parameters include advective flows sediment transport velocities dispersion coefficients cross sectional areas and characteristic lengths Although the nominal units expected by the model are SI English or other units can be used along with proper specification of conversion factors Advective Flow m sec Steady or unsteady flows can be specified between adjoining segments as well as entering or leaving the network as inflow or outflow The user must be careful to check for continuity errors as the model does not require that flow continuity be maintained For example the user may specify that more flow enter a segment than leaves For simulations using hydrodynamic results from the HYD file flow continuity is automatically maintained Figure 3 14 Dispersion Coefficients m sec Dispersive mixing coefficients can be specified between adjoining segments or across open water boundaries These coefficients can model pore water diffusion in benthic segments vertical
123. ation is necessary to refine the initial estimates 7 3 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Relationship Between Stream Velocity Particle Size and the Regimes of Sediment Erosion Transport and Deposition 1000 500 g 20 200 E L3 100 Z 5 o 20 Q 20 7 TRANSPORTATION w 10 gt 5 d 3 tr 2 f nn 1 z n 05 03 z 02 0 1 amp 888 3 233 23 223 7 7 e s CLAY SILT SANO PARTICLE SIZE DIAMETER nm Figure 7 1 Sediment Transport Regimes Graf 1971 7 1 2 Sediment Loading Sediment loading derives primarily from watershed erosion and bank erosion These can be measured or estimated by several techniques and input into each segment as a point source load For some problems long term average sediment loads can be calculated using the Universal Soil Loss Equation Wischmeier and Smith 1978 A useful treatment of this process is given by Mills et al 1985 This technique works poorly for short term or inherently dynamic problems because much of the sediment loading occurs during a few extreme storm or snow melt events If available suspended sediment data at local gaging stations can be extrapolated to provide areawide loading estimates Alternatively daily runoff loads can be simulated with a watershed model and read in directly from an appropriately formatted nonpoint source loading file TA DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 7 1 3 The Sedim
124. ation rate constants and MacKay s method for gas transfer Input data required for the same as for option 2 listed above For flowing systems wind speed and air temperature are not used and may be omitted 11 6 10 Volatilization Option 4 In this option volatilization rates in flowing systems are calculated using reaeration rates calculated from Covars method and a gas transfer rate of 100 m day In quiescent systems volatilization is computed from O Connors equations for liquid and gas transfer Input data required for option 4 are listed below For flowing systems wind speed and air temperature are not used and may be omitted For quiescent systems water velocity may be omitted Water Velocity m sec Variable current velocities are calculated from flow using hydraulic geometry coefficients as described in Chapter 2 For most situations no further input is required from the user If an estuary is being simulated under tidalaverage conditions however the net flows do not provide realistic ambient water velocities for use in volatilization calculations In this case the user should enter time and segment variable water velocities using parameter 1 VELEN and time functions 5 8 VELN 1 4 The parameter VELEN indicates which velocity function will be used by the model for each segment Values of 1 0 2 0 3 0 or 4 0 will call time functions VELN 1 VELN 2 VELN 3 and VELN 4 respectively Water velocities should then be entered via the
125. ations must be specified for PHYT expressed as ug L chlorophyll a Time variable concentrations must also be specified for either ON NH3 NO3 OP PO4 CBOD and DO A boundary segment is 9 39 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 characterized by water exchanges from outside the network including tributary inflows downstream outflows and open water dispersive exchanges Waste Loads kg day For each point source discharge time variable PHYT ON NH3 NO3 OP PO4 CBOD and DO loads can be specified These loads can represent municipal and industrial wastewater discharges or urban and agricultural runoff If any phytoplankton loads are specified they should be in units of kg carbon day Solids Transport Field The transport fields associated with particulate settling must be specified under initial conditions Solids 1 Field 3 is recommended for ON OP and CBOD Solids 2 Field 4 is recommended for PHYT Solids 3 Field 5 is recommended for PO4 Solid Density g c P A value of 0 can be entered for the nominal density of PHYT ON NH3 NO3 OP PO4 CBOD and DO This information is not used in EUTRO Initial Concentrations mg L Concentrations of all variables in each segment must be specified for the time at which the simulation begins Concentrations of PHYT are expressed as ug L chlorophyll a Dissolved Fraction The dissolved fraction of each variable in each segment must be specified
126. base however the model also must have sufficient process integrity Examples of this type of application include waste load allocation to protect water quality standards and feasibility analysis for remedial actions such as tertiary treatment phosphate bans or agricultural best management practices Analysis of the problem should dictate the spatial and temporal scales for the modeling analysis Division of the water body into appropriately sized segments was discussed in Section Model Network The user must try to extend the network upstream and downstream beyond the influence of the waste loads being studied If this is not possible the user should extend the network far enough so that errors in specifying future boundary concentrations do not propagate into the reaches being studied The user also should consider aligning the network so that sampling stations and points of interest such as water withdrawals fall near the center of a segment Point source waste loads in streams and rivers with unidirectional flow should be located near the upper end of a segment In estuaries and other water bodies with oscillating flow waste loads are best centered within segments If flows are to be input from DYNHYD then a WASP 5 8 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 segment must coincide with each hydrodynamic junction Benthic segments which are not present in the hydrodynamic network may nevertheless be include
127. bonaceous biochemical oxygen demand and dissolved oxygen The reduction of dissolved oxygen is a consequence of the aerobic respiratory processes in the water column and the anaerobic processes in the underlying sediments Because both these sets of processes can contribute significantly it is necessary to formulate their kinetics explicitly Carbonaceous Biochemical Oxygen Demand OO te Kio Caka Ci Kroo Cs Veil fos 532 Es Tiat 17 8 Cs D Cs id on ces Death Onilaton seating Denitrification Dissolved Oxygen as Cs 64 G SOD 32 4814 32 P hea C Caj dal Cs 2 kal Ci S e 4 Gal T4 0 Pawn C knoe a uox ae za D MII Ev alla al Faannten Orilaton Nitrification Sediment demand Phypphaken growth Forpiraton Figure 8 2 Oxygen balance equations The methodology for the analysis of dissolved oxygen dynamics in natural waters particularly in streams rivers and estuaries is reasonably well developed O Connor and Thomann 1972 The major and minor processes incorporated into EUTRO are discussed below The reader should refer to the kinetic equations summarized in Figure 8 2 and the reaction parameters and coefficients in Table 8 1 8 3 DRAFT Water Quality Analysis Simulation Program WASP Table 8 1 CBOD and DO Reaction Terms Version 6 0 Value from Potomac Estuary Model Description Notation Units Oxygen to carbon ratio aoc 32 12 mg O0 mgC Phytoplankton nitrogen carbon ratio anc
128. boratory elemental analysis of overall phytoplankton population 3 Estimates of cell composition based upon field data Once the stoichiometric ratios have been determined the mass balance equations may be written for the nutrients in much the same way as is done for the phytoplankton biomass The primary interaction between the nutrient systems and the phytoplankton system is the reduction or sink of nutrients associated with phytoplankton growth A secondary interaction occurs wherein the phytoplankton system acts as a source of nutrients due to release of stored cellular nitrogen and phosphorus during algal respiration and death 9 2 The Phosphorus Cycle Three phosphorus variables are modeled phytoplankton phosphorus organic phosphorus and inorganic orthophosphate phosphorus Organic phosphorus is divided into particulate and dissolved concentrations by spatially variable dissolved fractions Inorganic phosphorus also is divided into particulate and dissolved concentrations by spatially variable dissolved fractions reflecting sorption The phosphorus equations are summarized in Figure 9 4 9 16 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Phytoplankton Phosphorus O C 4A Vsa Gn dy C4 Dn ag Ca ape C4 a D Crowh Death tiing Organic Phosphorus oC 2 V31 i ig Ape Jop Ca kOe in Cs ag gan Cs a KmpesC 4 D Death Mierilsiton Satting Tnorganic Phosphorus acs C4 L D
129. breakdown of the benthic organic carbon Both reactions are sinks of the oxygen and rapidly drive its concentration negative indicating that the sediment is reduced rather than oxidized The negative concentrations computed can be considered the oxygen equivalents of the reduced end products produced by the chains of redox reactions occurring in the sediment Because the calculated concentration of oxygen is positive in the overlying water it is assumed that the reduced carbon species negative oxygen equivalents that are transported across the benthic water interface combine with the available oxygen and are oxidized to CO and H2O with a consequent reduction of oxygen in the overlying water column The sediment mass 9 31 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 balance equations for carbonaceous BOD and DO together with the equation for sediment oxygen demand are presented in Figure 4 3 and Table 4 2 9 5 Model Implementation To simulate eutrophication with WASP6 use the preprocessor to create a EUTRO input dataset For the portions of the dataset describing environment transport and boundaries EUTRO model input will be similar to that for the conservative tracer model as described in Chapter 6 To those basic parameters the user will add combinations of transformation parameters and perhaps solids transport rates EUTRO kinetics can be implemented using some or all of the processes and kinetic terms de
130. by diffusion coefficients and divided by characteristic mixing lengths to obtain pore water exchange flows Characteristic Mixing Lengths m The characteristic mixing length must be specified for adjoming segments where pore water diffusion occurs The value for a mixing length is typically equal to the average depth of the pore water segments involved in the exchange These mixing lengths are divided into the product of the diffusion coefficients and cross sectional areas to obtain pore water exchange flows 10 4 4 Boundary Parameters This group of parameters includes boundary concentrations waste loads and initial conditions Boundary concentrations must be specified for any segment receiving flow inputs outputs or exchanges Initial conditions include not only initial concentrations but also the density and solids transport field for each solid and the dissolved fraction in each segment Boundary Concentrations mg L At each segment boundary time variable concentrations must be specified for each toxicant and for each solids type simulated A boundary segment is characterized by water exchanges from outside the network including tributary inflows downstream outflows and open water dispersive exchanges Waste Loads kg day For each point source discharge time variable toxicant and solids loads can be specified These loads can represent municipal and industrial wastewater discharges or urban and agricultural runoff So
131. c charged ions These reactions are rapid and are generally assumed to be at local equilibrium At equilibrium the distribution of chemicals between the neutral and the ionized species is controlled by the pH and temperature of the water and the ionization constants Ionization can be important because of the different toxicological and chemical properties of the neutral and ionized species For example in some cases only the neutral form of the chemical may react or be transported through biotic membranes resulting in toxicity As a result it is often necessary to compute the distribution of chemicals among ionic forms as well as to allow them to react or transform at different rates For example in TOXI different sorption and reaction constants e g for hydrolysis biodegradation photolysis etc may be specified for each ionic form of the chemical 11 3 1 Overview of TOXI lonization Reactions In TOXI each of the three possible chemicals being simulated may occur in up to five forms including 1 the neutral molecule 2 singly charged cations 3 doubly charged cations 4 singly charged anions and 5 doubly charged anions Each of the neutral or ionic species may also occur in the dissolved phase or sorbed to dissolved organic carbon DOC or the three solids types A total of 25 forms of each chemical may occur Each chemical form may have different reactivities as reflected by different degradation or transformation rates TOXI ma
132. c Phosphorus eC 8 T 20 T 20 a K pzp ours dpe Jop Ca Kopp Gorn J pa Cs Alaldacomporiten Mueiihsaton Inorganic Phosphorus 9C T 2 I 20 Ep Kpgn ep Ane 1 fop Cyt kopp opp Joe Ce Algldecomporition Mineralization E Flux 2 Cy fy Cu Fu D fox luft ra gnontj watr sa grentI Figure 9 8 Benthic nutrient equations Table 9 6 Benthic nutrient reaction coefficients Value from Potomac Estuary Study D escription Notation Units 9 28 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Value from Potomac Estuary Study Anaerobic algal decomposition rate kpzp 0 02 day Temperature coefficient Epzp 1 08 none Organic nitrogen decomposition rate koND 0 0004 day Temperature coefficient Eonp 1 08 none Organic phosphorus decomposition rate korp 0 0004 day Temperature coefficient Eopp 1 08 none Fraction inorganic phosphorus dissolved in fps 0 045 0 001 none benthic layer Diffusive exchange coefficient EDIF 2 2 5 x 10 4 m day Benthic layer depth Dj 0 1 0 3 m Benthic layer j Water column i WASP6 allows a more detailed parameterization of settling into the benthos that includes not only a downward settling velocity but an upward resuspension velocity as well In this context then the net particulate flux to the sediment is due to the difference between the downward settling flux and the upward resuspension flux Benthic Depth One of the first decisions to be made regarding the benthic layer is to
133. c chemical simulations the dissolved fraction will be internally calculated from partition coefficients and sediment concentrations The density of each constituent must be specified under initial conditions For tracers this value should be set to 1 0 6 3 Model Implementation To simulate a tracer with WASP6 use the preprocessor or text itor to create a TOXI input file The preprocessor will create an input file with parameters in the proper fields Using a text editor the user must take care to enter parameters into the proper fields The model input parameters are organized below as they are presented in the preprocessor 6 4 Model Input Parameters This section summarizes the input parameters that must be specified in order to solve the WASP6 mass balance equation Input parameters are prepared for WASP6 in four major sections of the preprocessor environment transport boundaries and transformations 6 4 1 Environment Parameters These parameters define the basic model identity including the segmentation and control the simulation Simulation Type The user must specify which WASP6 model will be run with the dataset The present choices are TOXI or EUTRO Figure 3 6 Simulation Titles The user may specify a 2 line title for the simulation This title may include any descriptive information on the water body time frame pollutants simulation parameters etc The user may also specify the properly positioned names
134. ces reasonably results If the file you are trying to import is incomplete or can t be read successfully by the DOS version of WASP the import may only be partially successful 3 7 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 To import a file the user should open the old file with the preprocessor This will initiate the import of the data The user will see a description of activities as the import progresses 3 5 2 Exporting Old WASP Input Files WASP6 can export a WIF file format to the previous WASP file format This would be useful for sharing input files with other people who do not use WASP6 The Export function is available from the file menu you will be required to provide a filename in which to export the information 3 5 3 User Preferences The user has the ability to set several options within WASP6 The first option is whether to display a condensed version of the toolbar or the complete toolbar The user also has the ability to enable logging This option is used for debugging purposes only The logging function will generate a logging of all communications between the WASP6 program ad the model DLL s The last option allows the user to specify that the model runtime grid remains visible whether the model is running or not This is a good way to look at the final values predicted by the model s AScl WIN WASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO Ele WINAWASP
135. cesses in WASP6 for various water quality constituents The equations solved by WASP6 are based on the key principle of the conservation of mass This principle requires that the mass of each water quality constituent being investigated must be accounted for in one way or another WASP6 traces each water quality constituent from the point of spatial and temporal input to its final point of export conserving mass in space and time To perform these mass balance computations the user must supply WASP6 with input data defining seven important characteristics e simulation and output control e model segmentation e advective and dispersive transport e boundary concentrations e point and diffuse source waste loads e kinetic parameters constants and time functions e initial concentrations These input data together with the general WASP6 mass balance equations and the specific chemical kinetics equations uniquely define a special set of water quality equations These are numerically integrated by WASP6 as the simulation proceeds in time At user specified print intervals WASP6 saves the values of all display variables for subsequent retrieval by the post processor program These programs allow the user to interactively produce graphs and tables of variables of all display variables 5 1 General Mass Balance Equation A mass balance equation for dissolved constituents in a body of water must account for all the material entering and leavin
136. chemical to accumulate in bed sediment or bioconcentrate in fish Sorption may retard such reactions as volatilization and base hydrolysis or enhance other reactions including photolysis and acid catalyzed hydrolysis Sorption reactions are usually fast relative to other environmental processes and equilibrium may be assumed For environmentally relevant concentrations less than 10 M or one half water solubility equilibrium sorption is linear with dissolved chemical concentration Karickhoff 1984 or 10 4 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 10 4 Cy Kp Cw At equilibrium then the distribution among the phases is controlled by the partition coefficients Kp As developed in Chapter 7 the total mass of chemical in each phase is controlled by Ks and the amount of solid phase present ignoring here any DOC phase so that Equation 10 5 n Tu py K M and Equation 10 6 K 9 M n Kp Ms S These fractions are determined in time and space throughout a simulation from the partition coefficients internally calculated porosities and simulated sediment concentrations Given the total concentration and the phase fractions of chemical i in segment j the dissolved and sorbed concentrations are uniquely determined Equation 10 7 Cwj Cy f y Equation 10 8 C7 Cy f s In addition to the assumption of instantaneous equilibrium implicit in the use of these equations
137. cid neutral and base hydrolysis rate constant First Order Hydrolysis Rate Constants day The user may input overall base neutral and acid hydrolysis rate constants using constants 181 182 and 183 for chemical 1 constants 781 782 and 783 for chemical 2 and constants 1381 1382 and 1383 for chemical 3 The rates are first order and are applied to the total chemical If any one of these first order rates are specified in input they will be used regardless of whether other hydrolysis constants are specified INPUT VARIABLE 1384 Reference Temperature TREFH C Alkaline Hydrolysis KH201 1 Option 2 M lday 201 801 1401 Neutral Hydrolysis KH202i1 day 1406 sediment 1411 aqueous 216 816 1416 Acid 11 32 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Hydrolysis KH203 1 M day Activation Energy Ea Under this option the reaction coefficients can be specified as constants If the chemical simulated does not ionize as controlled by input of the ionization constants then acid base and neutral hydrolysis constants may be input for the dissolved DOC sorbed and sediment sorbed phases of the chemical as summarized in Table 7 11 If ionization of the chemical is allowed then constants may be input for the dissolved DOC sorbed and sediment sorbed phases of each ionic specie simulated In addition the pH must be supplied in order to compute acid and base hydrolysis The pH is input
138. cous forces dominate momentum transfer Equation 8 7 is used for wind speed over 20 m sec where interfacial conditions are rough and momentum transfer is dominated by turbulent eddies Equation 8 6 is used for wind speeds between 6 and 20 m sec and represents a transition zone in which the diffusional sublayer decays and the roughness height increases The user is referred to O Connor 1983 for details on the calculation of air density air and water viscosity the drag coefficient the effective roughness and Ay Small scale represents laboratory conditions Large scale represents open ocean conditions Medium scale represents most lakes and reservoirs Dissolved oxygen saturation Cs is determined as a function of temperature in degrees K and salinity S in mg L APHA 1985 Equation 8 8 In C 2 139 34 1 5757 10 T g 6 64239 10 T 1 243810 r 8 6219 10 r 0 5535 S 0 031929 19 428 T 3867 3 T R 8 2 2 Carbonaceous Oxidation The long history of applications has focused primarily on the use of BOD as the measure of the quantity of oxygen demanding material and its rate of oxidation as the controlling kinetic reaction This has proven to be appropriate for waters receiving a heterogeneous combination of organic wastes of municipal and industrial origin since an aggregate measure of their potential effect is a great simplification that reduces a complex problem to one of tractable dimensions 8 7 DRAFT Wa
139. cription Notation Value Units Temperature coefficient Epzp none Diffusive exchange coefficient EDIF 2 0 x 104 m day Benthic layer depth Dj 0 2 0 7 m Benthic layer j Water column i 8 3 Model Implementation To simulate dissolved oxygen with WASP6 use the preprocessor to create a EUTRO input dataset For the portions of the dataset describing environment transport and boundaries EUTRO model input will be similar to that for the conservative tracer model as described in Chapter 2 To those basic parameters the user will add combinations of transformation parameters and perhaps solids transport rates EUTRO kinetics can be implemented using some or all of the processes and kinetic terms described above to analyze dissolved oxygen problems For convenience four levels of complexity are identified here 1 Streeter Phelps 2 modified Streeter Phelps 3 full linear DO balance and 4 nonlinear DO balance Please note that the discrete levels of simulation identified here are among a continuum of levels that the user could implement The four implementation levels are described briefly below along with the input parameters required to solve the DO balance equations in EUTRO Input parameters are prepared for WASP6 in four major sections of the preprocessor environment transport boundaries and transformation Basic model parameters are described in Chapter 2 and will not be repeated here Six of the eight EUTRO state variables that ca
140. curve assigned to that y axis will be scaled and plotted independently of any curve assigned to 1 s y axis Observed Data Observed data can be added to any x y plot window Before observed data is available for plotting the observed data database must have been opened for use by the user Observed data is opened using the open file dialog box Once the observed data database has been opened the data will be available for plotting in the x y plot window To select observe data to plot the user should press the Observed radio button If there is more 4 66 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 than one database file loaded the user will be presented a choice of file in the predicted data window The user should select the database file select the variable from the variable window and then select the Station ID from the segment window Note Observed data can be plotted exclusively if the user desires Legend Description The user can control the information that is automatically placed in the x y plot legend that is used to illustrate the contents of the graph The user has four options for the legend 1 Data Set setting this radio button will cause the use of the dataset name selected in the Predicted Data dialog window for the legend of the defined line 2 Variable setting this radio button will cause the use of the variable name selected in the Variable dialog window for the legend of th
141. d EUTRO simulates the transport and transformation reactions of up to eight state variables illustrated in Figure 9 1 They can be considered as four interacting systems phytoplankton kinetics the phosphorus cycle the nitrogen cycle and the dissolved oxygen balance The general WASP6 mass balance equation is solved for each state variable To this general equation the EUTRO subroutines add specific transformation processes to customize the general mass balance for the eight state variables in the water column and benthos Following a short summary of the material cycles the rest of this section covers the specific details for the several transformation sources and sinks 9 2 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 9 1 1 Phosphorus Cycle Dissolved or available inorganic phosphorus DIP interacts with particulate inorganic phosphorus via a sorption desorption mechanism DIP is taken up by phytoplankton for growth and is incorporated into phytoplankton biomass Phosphorus is returned from the phytoplankton biomass pool to dissolved and particulate organic phosphorus and to dissolved inorganic phosphorus through endogenous respiration and nonpredatory mortality Organic phosphorus is converted to dissolved inorganic phosphorus at a temperature dependent mineralization rate 9 1 2 Nitrogen Cycle The kinetics of the nitrogen species are fundamentally the same as the phosphorus system Ammonia and nitrate are
142. d White radio button from the configuration menu or press the Black amp White Color toggle icon from the toolbar To print the currently active x y plot the user should press the print icon from the toolbar A standard windows print dialog box will appear The user can select the appropriate output device to print the figure To File The user has the option of saving a bitmap file of the currently active x y plot to a file This is useful for saving simulation results for comparison or inclusion into a presentation or publication To save the currently active x y plot to a file as a bitmap the user should press the save graph to bitmap icon from the toolbar The user will be given a standard windows file dialog box that allows the user to designate the drive directory and filename To Clipboard The user also has the ability to copy a graphic image of the currently active x y plot to the Windows clipboard Once an image is copied to the Windows clipboard it can be pasted into virtually any Windows program that has graphics support 4 75 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 To copy the graphics image to the clipboard the user should press the copy to clipboard icon from the toolbar Once the image has been copied it is available for pasting 4 4 10 Creating Tabled Data Internal data structures are utilized to store the actual numbers that are used to generate the x y plots A method is provided for
143. d as a redox pair Equation 11 76 Cit RO CotRH where Ci reduced chemical C oxidized chemical RO oxidizing agent RH reducing agent Laboratory kinetics studies can control the concentrations of RO and RH to determine rate constants for both oxidation and reduction These may be specified as constants ko and kg Yield coefficients Yoi2 and Ygo must also be specified as constants The spatially variable concentrations RO2 and RH2 must be specified as parameters Implementation 11 50 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 The input data requirements for the second order reactions include the second order reaction rate constants that may be specified for each specie and sorbed form dissolved DOC sorbed and sorbed to particulate If the mtes are to be temperature corrected then the user may supply the reference temperature at which the extra reaction rates were measured and the activation energy for the reaction The rates will then be adjusted using a temperature based Arrhenius function If activation energy is not supplied no temperature corrections will be performed The extra property of the aquatic environment that affects the extra reaction is specified to the model as a parameter which may vary between segments The units of the extra property must be consistent with those used for the second order rate constant The product of the extra property and second order rate con
144. d by the user when the calculated field was created To select and view the variables in list the user can use the scroll bar to move through the list To select a variable to plot the user should click the left mouse button on the desired variable to select The selected variable will become highlighted Selecting Segment The last item that has to be selected before an x y plot can be created is what segment or computational element to plot Once a Predicted Data file is selected a list of the available segments to plot is displayed in the Segment dialog window To select and view the segments in the list the user can use the scroll bar to move through the list To select a segment to plot the user should click the left mouse button on the desired segment The selected variable will become highlighted If the data source is an observed data database the segment is typically a station identification number Representation The representation radio button dialog box allows the user to assign a_ specific characteristic for the defined curve The user has the option of drawing a line symbol line amp symbol or force solid for the defined curve Note A different line style color and symbol is automatically created for each line defined in a particular x y plot window Second Y The user may assign any number of the defined curves to the second y axis scale located on the right hand side of graph When a second y is requested the
145. d for every boundary segment To specify a boundary for a system move the cursor to the system that a boundary needs to be specified and right click on the system 3 27 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WIN AWASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO File Project Pre processor Model Post Processor Help Boundaries a Wasp Segment Wasp Segment Wasp Segment a Wasp Segment a Wasp Segment Wasp Segment Wasp Segment Wasp Segment a Wasp Segment a Wasp S t dp Wasp Segment Time functions for segment 8 Wasp Segment Ammonia Dae Time IF 1 1 1985 12 00 AM 10 16 2258 12 00 4M Pi Insert 7 Delete EZ Graph Fucac o X Een pap cc ee N Astar amp eu if 89 Paint Shop Pro Image22 aset WIN WASP B 10314M Figure 3 15 Boundary Concentration Definitions 3 13 1 Boundary Time Function The time function table allows the user to enter time variable boundary concentrations mg l The user must provide the date time and concentration Note For chlorophyll a boundary conditions the units are g l 3 14 Loads Waste loads may be entered into WASP6 for each of the systems for a given segment To add a load right mouse click on the system select add load and check the segments that will be receiving a load for the selected system Once this is done the use
146. d in the WASP network WASP segment numbering does not have to be the same as DYNHYD junction numbering Segments stacked vertically do not have to be numbered consecutively from surface water segments down Once the network is set up the model study will proceed through four general steps involving in some manner hydrodynamics mass transport water quality transformations and environmental toxicology The first step addresses the question of where the water goes This can be answered by a combination of gaging special studies and hydrodynamic modeling Flow data can be interpolated or extrapolated using the principle of continuity Very simple flow routing models can be used very complicated multi dimensional hydrodynamic models can also be used with proper averaging over time and space At present the most compatible hydrodynamic model is DYNHYD The second step answers the question of where the material in the water is transported This can be answered by a combination of tracer studies and model calibration Dye and salinity are often used as tracers The third step answers the question of how the material in the water and sediment is transformed and what its fate is This is the main focus of many studies Answers depend on a combination of laboratory studies field monitoring parameter estimation calibration and testing The net result is sometimes called model validation or verification which are elusive concepts The success of th
147. d in the water column these organisms use oxygen to oxidize organic material Under the anaerobic conditions found in the sediment bed or during extremely low oxygen conditions in the water column however these organisms are able to use NO as the electron acceptor The process of denitrification is included in the modeling framework simply as a sink of nitrate The kinetic expression for denitrification in EUTRO contains three terms a first order rate constant a temperature correction term and a DO correction term The first two terms are standard The third term represents the decline of the denitrification rate as DO levels rise above 0 The user may specify the half saturation constant Kwos which represents the DO level at which the denitrification rate is reduced by half The default value is zero which prevents this reaction at all DO levels Denitrification is assumed to always occur in the sediment layer where anaerobic conditions always exist 9 4 The Dissolved Oxygen Balance Five state variables participate in the DO balance phytoplankton carbon ammonia nitrate carbonaceous biochemical oxygen demand and dissolved oxygen A summary is illustrated in Figure 9 1 The reduction of dissolved oxygen is a consequence of the aerobic respiratory processes in the water column and the anaerobic processes in the underlying sediments Both these processes contribute significantly and therefore it is necessary to formulate their kinetics
148. defines the advective and dispersive transport of model variables 9 34 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Number of Flow Fields To simulate settling of ON and OP the user should select solids 1 flow under advection To simulate settling of PHYT the user should select solids 2 flow To simulate PO4 settling the user should select solids 3 flow The user should also select water column flow Particulate Transport m sec Time variable settling and resuspension rates for solids 1 solids 2 and solids 3 can be input using the continuity array BQ and the time function QT For each solids flow field cross sectional exchange areas m for adjacent segment pairs are input using the spatially variable BQ Time variable settling velocities can be specified as a series of velocities in m sec versus time If the units conversion factor is set to 1 157e 5 then these velocities are input in units of m day These velocities are multiplied internally by cross sectional areas and treated as flows that carry particulate organic matter out of the water column 9 6 3 Boundary Parameters This group of parameters includes boundary concentrations waste loads and initial conditions Boundary concentrations must be specified for any segment receiving flow inputs outputs or exchanges Initial conditions include not only initial concentrations but also the density and solids transport field for each solid and the
149. dequate level of substrate concentration the growth rate proceeds at the saturated rate for the ambient temperature and light conditions present At low substrate concentration however the growth rate becomes linearly proportional to substrate concentration Thus for a nutrient with concentration N in the j segment the factor by which the saturated growth rate is reduced is Nj Km Nj The constant Km called the Michaelis or half saturation constant is the nutrient concentration at which the growth rate is half the saturated growth rate Because there are two nutrients nitrogen and phosphorus considered in this framework the Michaelis Menten expression is evaluated for the dissolved inorganic forms of both nutrients and the minimum value is chosen to reduce the saturated growth rate as given by Equation 9 12 Carbon Chlorophyll a ug C ug Chlorophyll a Sampling Period O bserved O bserved Predicted Mean Range Range July 20 0 ct 6 119701 45 25 68 24 28 August 1 29 19772 28 12 37 23 26 Sept 7 28 19782 21 15 27 26 30 Sept 7 28 19783 26 30 1 Elemental analysis of blue green algae 2 Laboratory elemental analysis of overall phytoplankton population 3 Estimates of cell composition based upon field data Equation 9 12 tis DIN DIP Kw DIN K p DIP 9 10 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 At the user s discretion the multiplicative formulation for nutrient limitation may be selected
150. diffusion in lakes and lateral and longitudinal dispersion in large water bodies Values can range from 10 m sec for molecular diffusion to 5x10 m sec for longitudinal mixing in some estuaries Values are entered as a time function series of dispersion and time in days Figure 3 13 Cross Sectional Area mY Cross sectional areas are specified for each dispersion coefficient reflecting the area through which mixing occurs These can be surface areas for vertical exchange such as in lakes or in the benthos Areas are not modified during the simulation to reflect flow changes Figure 3 13 6 17 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Characteristic Mixing Length m Mixing lengths are specified for each dispersion coefficient reflecting the characteristic length over which mixing occurs These are typically the lengths between the center points of adjoining segments A single segment may have three or more mixing lengths for segments adjoming longitudinally laterally and vertically For surficial benthic segments connecting water column segments the depth of the benthic layer is a more realistic mixing length than half the water depth Figure 3 13 6 4 3 Boundary Parameters This group of parameters includes boundary concentrations waste loads and initial conditions Boundary concentrations must be specified for any segment receiving flow inputs outputs or exchanges Initial conditions include no
151. dows using the same backdrop file or any others that are loaded z Creates a Spatial Animation Window using GIS coverage s This option is only available when GIS coverage s have been opened One of the GIS coverage s 4 42 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 required is model network coverage Creates x y plot Window This opens an x y plot window only after model data BMD or observed database data DB have been loaded The user can open as many of these windows as desired to review any data that is loaded gg Edits the load observed data database 4 2 Model Output Selection The Graphical Post Processor was designed to allow the user to rapidly evaluate the results of the WASP model simulations and its support programs Observed data can also be stored in a database format Four types of data are recognized The first data type is created from the execution of the WASP models BMD The output from WASP is written in a binary file format The model results cannot be read directly by any other program The second file type that can be read is a Paradox table file DB The Paradox table file is used to provide observed field data to be plotted against model predictions The third file type is an ArcView shape file These files can be used in the spatial analysis mode to aid the user in displaying the model network with respect to its geography and surrounding characteristics The last f
152. e defined line 3 Segment setting this radio button will cause the use of the segment name selected in the Segment dialog window for the legend of the defined line 4 User Defined setting this radio button will cause the use of the user defined item to be placed in the User Defined Dialog box Note If the user does not want a legend the user should select user define and not type anything into the user defined dialog box 4 4 4 OK Cancel Once this information was been selected along with any other user definable parameters the user should press Okay to generate the graph The observed data will be plotted on the x y graph along with any predicted or user selected data If they press cancel all the information entered will be lost 4 67 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 4 4 5 Zooming the Axes The user can zoom any of the axes within the x y plot window The user can zoom the x axis yl axis and y axis exclusively or in combination Zooming the axis allows the user to view data in smaller time or concentration scales to visualize subtle changes in the model results Zooming X Axis The user has several options available performing a zoom function The quickest and most efficient way to zoom the axis is to place the mouse cursor close to the xaxis line within the plot area at the beginning time of the area to zoom Then press and hold the left mouse and paint the area to zo
153. e dissolved organic carbon concentrations using parameter 6 DOC 11 5 8 Option 3 Computation of the Organic Carbon Partition Coefficient Under this option the user allows the model to compute the Kec from a specified octanol water partition coefficient Kow The model then computes the Koc using equation 7 39 This option will not be used if values for the log Koc are input Octanol Water Partition Coefficient L L The user may specify the logie of the octanol water partition coefficient using constant LKOC Constant numbers are given in Table 7 7 11 18 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Correlation Coefficients The user should specify correlation coefficients relating Kow with Koc using constants AO and Al AO and AI are the intercept and the slope in the correlation described by equation 7 39 Default values are log 0 6 and 1 0 respectively If these constants are not entered then the correlation becomes Koc 0 6 Kow Constant numbers are given in Table 7 7 Fraction Organic Carbon The user should specify the segment variable fraction organic carbon for each solids type simulated using parameters FOC L1 FOC L2 and FOC L3 Parameter numbers for solids 1 2 and 3 are 7 8 and 9 respectively Dissolved Organic Carbon mg L The user may specify segment variable dissolved organic carbon concentrations using parameter 6 DOC 11 5 9 Option 4 Solids Dependant Partitioning
154. e second network was used to investigate the lake wide spatial and seasonal variations in eutrophication The third network was used to predict changes in near shore eutrophication of Rochester Embayment resulting from specific pollution control plans 5 4 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 SPATIAL SCALES USED IN LAKE ONTARIO ANALYSIS HORIZONTAL MODEL NUMBER OF SCALE km 2 DESIGNATION SEGMENTS EPILIMNION SEGMENTS LAKE 1 13 000 LAKE 3 200 1000 an ROCHESTER 72 10 100 EMBAYMENT Figure 5 3 Spatial Scales used in Lake Ontario Analysis As part of the problem definition the user must determine how much of the water quality frequency distribution must be predicted For example a daily average dissolved oxygen concentration of 5 mg L would not sufficiently protect fish if fluctuations result in concentrations less than 2 mg L for 1096 of the time Predicting extreme concentration values is generally more difficult than predicting average values Figure 5 4 illustrates typical frequency distributions predicted by three model time scales and a typical distribution observed by rather thorough sampling as they would be plotted on probability paper The straight lines imply normal distributions Reducing the model time step and consequently segment size allows better simulation of the frequency distribution This increase in predictive ability however also entails
155. e steps At must be specified along with the time interval over which they apply If user specified time step option is used these time steps will be used during the simulation If the WASP calculated time step is used the model will calculate time steps internally the time steps given here are the maximum allowed Figure 3 6 amp Figure 3 18 Given specific network and transport parameters time steps are constrained within a specific range to maintain stability and minimize numerical dispersion or solution inaccuracies To maintain stability at a segment the advected dispersed and transformed mass must be less than the resident mass 6 15 1 0 500 100 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 6 16 LOC ZRCj US KV JAt lt V C Solving for At and applying the criterion over the entire network with appropriate factors gives the maximum stable step size used by WASP6 Equation 6 17 Vj 1 50 9 Min e O Ro SmV 7C i i k For purely advective systems Equation 17 sets the time step to 90 of the minimum segment travel time For purely dispersive systems Equation 17 sets the time step to 90 of the minimum segment flushing time For a linear reactive system with no transport Equation 6 17 sets the time step to 18 of the reaction time Usually At is controlled by advective or dispersive flows Numerical dispersion is artificial mixing caused by the finite difference approxima
156. e to three types of solids classes Table 6 1 To simulate a tracer the user should bypass solids and simulate chemical 1 with no decay A tracer is affected by transport boundary and loading processes only as described below Table 6 1 State Variables in Organic Chemical Model TOXT WASP6 uses a mass balance equation to calculate chemical mass and concentrations for every segment in a specialized network that may include surface water underlying water surface bed and underlying bed Simulated chemicals undergo several transport processes as specified by the user in the input dataset Chemicals are advected and dispersed among water segments and exchanged with surficial benthic segments by dispersive mixing Dissolved chemicals migrate downward or upward through percolation and pore water diffusion The transport boundary and loading processes for tracer chemicals are described below These same processes are also applied to the water quality variables described in subsequent chapters 6 2 Transport Processes Advective water column flows directly control the transport of dissolved and particulate pollutants in many water bodies In addition changes in velocity and depth resulting from variable flows can affect such kinetic processes as reaeration volatilization and photolysis An important early step in any modeling study is to describe or simulate water column advection properly In WASP6 water column flow is input via trans
157. e user must populate the database with their own data by using the insert record function pressing the sign The user can paste data into this table from other applications as well To do this the user needs to insert as many records that they will be pasting into the table 4 73 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 EN Post processor BEES File Edit View ObservedData Window Help zc FAY Observed Data C Program Files AScl WinWaspStandard examples example db DATE_TIME STATION_ID RESULT pipummmexdy o 0 CAPS NUM OVA MStart ES A Y wRascrwinnwasrs E Postprocessor X Paint Shop Pro Image3 Bl amp 9 57AM Figure 4 20 Creating Observed Data Database Loading a Database Once an observed data database has been created it must be loaded like any other file before it is available for plotting To load an observed data database file the user should select the open file icon or select it from the file menu Upon doing this a file dialog box will appear the user should set the file type to that of DB The user should navigate to the drive and directory where the observed data database is stored and select the file and press open Once the contents of the observed data database are read into memory they are available for plotting Selecting Data Selecting data from the observed data database file is done in the same manner as selecting data from the model simu
158. e user to activate constants by checking the Use dialog box and then entering a kinetic constant value When a constant is un checked the information is not passed onto the model but the users constant value is preserved 3 34 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 le x Constants data mms 80 0 0 5 0 0 0 0 sg Nitrification Rate 20c 0 0800 0 0000 10 0000 Nitrification Temperature Coefficient B 1080 0 0000 Half Saturation Nitrification Oxygen Limit B 2000 0 0000 stan S214 Y Part Shop Poner Figure 3 22 Kinetic Constant Definitions 3 19 Fill Calculate amp Graphing Most of the data entry screens have the ability to automatically fill and make calculations on the fields of the table To accomplish this marks the fields using standard Windows functions and then press the fill calculate button 3 35 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 le x me n s pu s EF Begin Execution of WAS EF Getting Model Parameter EF Getting Dispersion Inform EF Getting Segment Volume E gt Getting Flow Information E gt Getting Time Variable Boi E gt Getting Time Variable Loz E gt Getting Segment Specific Wasp Segment E gt Getting Kinetic Constants 5 Wasp Segment E gt Getting Environmental Tir Bp Wasp Segment EF Getting Initial Conditions Fill Calculate EF Begin Time Loop Simul 2 Fraction of Algal Death tk Fract
159. eceiving flow inputs outputs or exchanges Initial conditions include not only initial concentrations but also the density and solids transport field for each solid and the dissolved fraction in each segment Boundary Concentrations mg L At each segment boundary time variable concentrations must be specified for total solids or for each solids type simulated A boundary segment is characterized by water exchanges from outside the network including tributary inflows downstream outflows and open water dispersive exchanges Figure 3 15 Waste Loads kg day For each point source discharge time variable sediment loads can be specified for total solids or for each solids type simulated These loads can represent municipal and industrial wastewater discharges or urban and agricultural runoff Figure 3 16 Solids Transport Field The transport field associated with total solids or each solids type must be specified under initial conditions Solid Density g cm The average density of the total sediment or the density of each solids type must be specified This information is used to compute the porosity of benthic segments Porosity is a function of sediment concentration and the density of each solids type Figure 3 7 7 10 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Initial Concentrations mg L Concentrations of total sediment or of each solids type in each segment must be specified for the time at
160. echanism discussed subsequently phytoplankton chlorophyll a may be computed and used as the calibration and verification variable to be compared against observed chlorophyll a field data With a choice of biomass units established a growth rate that expresses the rate of production of biomass as a function of the important environmental variables temperature light and nutrients may be developed The specific growth rate Gpi in segment j is related to ke the maximum 20 C growth rate at optimum light and nutrients via the following equation 9 5 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 9 2 G pij K tc X ry X nj X RN where Xar7 the temperature adjustment factor dimensionless Xay the light limitation factor as a function of I f D and K dimensionless Xenj the nutrient limitation factor as a function of dissolved inorganic phosphorus and nitrogen DIP and DIN dimensionless T ambient water temperature C I incident solar radiation ly day f fraction day that is daylight unitless D depth of the water column or model segment m K total light extinction coefficient m DIP dissolved inorganic phosphorus orthophosphate available for growth mg L DIN dissolved inorganic nitrogen ammonia plus nitrate available for growth mg L An initial estimate of kj can be made based upon previous studies of phytoplankton dynamics and upon reported literature values such as
161. ed Field Used Scale Conversion je sutacewaer ma 1000 1000 m O Pore Water Flow Function Solds 1 __ Flow Function i iS m ss lm me 10 eass fm ume 310 evessiPecpinn TN 1m 3100 ArH 12 00 AM 12 00 AM 5 31 1985 Fem To Frac of flow gt Bounday E t WaspSegmer 2 Wasp Segmen 10000 2 Wasp Segmer 3 Wasp Segmen 3 Wasp Segmer 7 Wasp Segmen Wasp Segmer 8 Wasp Segmen 8 Wasp Seamer mi a 2 E 4 HH zE x rese D0 Al DO Al NIN eee UR EUR Figure 3 14 Flow Entry Forms 3 26 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 3 12 1 Flow Function The user has the ability to define 10 flow functions for each of the six flow fields Each flow function would have its own flow continuity input lower left table and time variable flow input lower right table The user must highlight the flow field and flow function in which to enter information WASP6 allows the user to provide names for each of the flow functions To insert an exchange function click on the insert button To delete a function select the function by highlighting the row and click on the delete button Note this will delete the corresponding segment pairs lower left table and the flow time function lower right table To insert flow functions for surface flow highlight the Surf
162. ed in accordance to the legend based upon the concentrations predicted by the model Wire Frame The mode displays the simulation results in a wire frame This mode differs from the shade mode in that the model computation elements are not filled with a color based upon 4 53 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 predicted concentrations The wire frame mode outlines the outside perimeter of the computational element in a color corresponding to the predicted concentration 4 3 13 GIS Configuration If the user creates a GIS spatial view the controls and options for configuring the windows are little different Figure 4 7 illustrates the configuration screen for the GIS option E Post processor e x File Edit View GIS Window Help Spatial Plot Parameters r Data Data Set Time C PROGRAM FILESSASCINWIN 71985 0 00 Variable Segment Depth m Y r Geometry z Select All eg Select None Move Down Color Display Labels Cancel I EFES NOW Ove Astar EAX i Paint Shop Pro F Post processor B 220PM Figure 4 7 GIS Spatial Plot Configuration Note GIS layer files must be loaded prior to this option being available The dataset variable delay options work exactly the same way as described above 4 3 14 Layers The user can select and order that GIS layers will be displayed The user
163. el is designed to provide a broad framework applicable to many environmental problems and to allow the user to match the model complexity with the requirements of the problem Although the potential amount and variety of data used by WASP6 is large data requirements for any particular simulation can be quite small Most often organic chemical simulations use only sorption and one or two transformation processes that significantly affect a particular chemical What is gained by the second order process functions and resulting input data burden is the ability to extrapolate more confidently to future conditions The user must determine the optimum amount of empirical calibration and process specification for each application Overview of WASP6 Organic Chemicals SYSTEM VARIABLE CHEMICAL 1 SOLIDS 1 SOLIDS3 CHEMICAL 2 CHEMICAL 3 SOLIDS 2 8 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Organic chemicals and associated solids are simulated using the TOXI program TOXI simulates the transport and transformation of one to three chemicals and one to three types of particulate material solids classes Table 7 1 The three chemicals may be independent or they may be linked with reaction yields such as a parent compound daughter product sequence The simulation of solids is described in Chapter 3 The simulation of organic chemicals is described below Organic chemical process routines are closely derived from the Expo
164. en KMNGI 0 Pyas 1 0 When KMNGI becomes very large Pyp approaches a value of C1 C1 C2 Phosphorus Half Saturation Constant mg P L The phosphorus half saturation constant for phytoplankton growth can be specified using constant KMPGI When inorganic phosphorus concentrations are at this level half reduces the phytoplankton growth rate Nutrient Limitation Option The nutrient limitation formulation can be specified using constant NUTLIM A value of O selects the minimum formulation which is recommended A value of 1 0 selects the multiplicative formulation The default value is O Respiration Rate day The average phytoplankton endogenous respiration rate constant and temperature coefficient can be input using constants KIRC and KIRT respectively Death Rate day The non predatory phytoplankton death rate constant can be input using constant KID No temperature dependance is assumed Grazing Rate day Zooplankton grazing can be specified using parameter ZOOSG time function ZOO and constant K1G Time and segment variable herbivorous zooplankton 9 41 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 populations are described as the product of the time variable population ZOO in mg zooplankton C L and segment specific ratios ZOOSG The grazing rate per unit zooplankton population in L mg zooplankton C day can be input using constant K1G The resulting grazing rate constant for phytoplankton is t
165. ent Bed The bed sediment plays an important role in the transport and fate of water quality constituents Sediment sorbed pollutants may be buried in the bed by deposition and sedimentation or they may be released to the water column by scour In WASP6 the movement of sediment in the bed is governed by one of two options In he first option bed segment volumes remain constant and sediment concentrations vary in response to deposition and scour No compaction or erosion of the segment volume is allowed to occur In the second option the bed segment volume is compacted or eroded as sediment is deposited or scoured Sediment concentration in the bed remains constant In both options chemical may be transported through the bed by pore water flow and dispersion The Constant Bed Volume Option The first bed option referred to as the constant volume option allows the sediment concentration of the bed to change according to the net flux of sediment Bed segments are located in reference to the rising or falling bed surface The rate at which the bed rises or falls is represented by a sedimentation velocity input in flow fields 3 4 and 5 for each sediment size fraction Sediment in the bed is added through deposition and lost through scour and sedimentation Assuming the depth of the bed remains constant and neglecting dispersive mixing the mass balance of sediment in a stationary upper bed is given by Equation 7 4 9 S d iz Wp S wet ws S
166. ent and time variable bacterial concentrations using parameter 11 PH and time functions 10 and 11 PHNW and PHNS If pH is to remain constant in time the user should enter segment mean values using parameter PH PHNW and PHNS should be omitted The user may enter time variable water column and benthic pH values via time functions PHNW and PHNS respectively as a series of concentration versus time values Parameter PH will then represent the ratio of each segment pH to the time function values The product of PH and the PHNW or PHNS function gives the segment and time specific pH values used by TOXI Group G Record 4 PARAM LI1 1 Group I Record 2 VALT 10 K VALT 11 K 11 5 Equilibrium Sorption Sorption is the bonding of dssolved chemicals onto solid phases such as benthic and suspended sediment biological material and sometime dissolved or colloidal organic material Sorption can be important in controlling both the environmental fate and the toxicity of chemicals Sorption may cause the chemical to accumulate in bed sediment or bioconcentrate in fish Sorption may retard such reactions as volatilization and base hydrolysis or enhance other reactions including photolysis and acid catalyzed hydrolysis Sorption reactions are usually fast relative to other environmental processes and equilibrium may be assumed For environmentally relevant concentrations less than 10 M or one half water solubility equilibrium sorption is linear w
167. ents the depth of the benthic layer is a more realistic mixing length than half the water depth 3 11 3 Dispersion Time Function Dispersive mixing coefficients can be specified between adjoining segments or across open water boundaries These coefficients may represent pore water diffusion in benthic segments vertical diffusion in lakes and lateral and longitudinal dispersion in large water bodies Values can range from 1x10 1 0 m2 sec for molecular diffusion to 5x102 m2 sec for longitudinal mixing in some estuaries Values are entered as a time function series of dispersion and time in days 3 12 Flows The flow groups works exactly the same way as the exchange group The only difference is that the advective group has 6 transport processes that can be defined by the user 3 25 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 1 Surface Water Flow This group transports both the particulate and dissolved fractions of a constituent If the user has selected the hydrodynamic linkage option they will not be able to enter information here 2 Pore Water This group only moves the dissolved fraction of a constituent 3 Solids Transport 1 This group moves solids field 1 4 Solids Transport 2 This group moves solids field 2 5 Solids Transport 3 This group moves solids field 3 6 Evaporation Precipitation This field adds subtracts water only from the model network No constituent mass is alter
168. epicting the results 3 Frequency Distribution the user specifies the number of concentration intervals to be used in the frequency distribution and calculation of the new curves 4 77 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 E Post processor x File Edit View XY Plot Window Help az Curve Calculator 2 x Curve Source 0 DO at Segment 1 in EXAMPLE Predicted Line s DO at 1 in C winwasp examples example db Observed Line Number of output points Segment Time Name numpoints cac 1 SEG TIME Data Name Calculation Type Tolerance seconds Calculation Name use Defined eo CALCULATED_1 CLE VAR SNM VR d stat E A Y vas winawasPs BS Paint Shop Pro Image4 Post processor E Bl 10054M Figure 4 22 Example of Curve Calculation The curve calculation screen has several dialog boxes that provide information to the user as well as allow the user to specify information and operations Curve Source The curve source dialog allows the user to select which loaded data source will be used for defining a curve Calculation Type The user has the option of selecting the type of calculation that should be performed The calculation type is selected from a drop down picklist as illustrated in Figure 4 23 The user has the option of user defined moving average or frequency distribution 4 78 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0
169. er wants TOXI to correct the rate constants for ambient segment temperatures then nonzero temperature correction factors should specified as constants User input for implementing biodegradation is given below Common Description Notation Range Units Observed first order degradation rate in water column Kaw 0 0 5 day O bserved first order degradation rate in benthos KBs 0 0 5 day Bacterial activity or concentration of bacterial agent Phac 102 107 cells mL Observed second order rate coefficients for specie i kai 0 106 mL cell day Biodegradation temperature coefficients for specie i phase j Qrj 1 5 2 5 Water temperature jl 4 30 C VARIABLE LIU c DmT ee KBW 141 741 1341 1342 146 746 136 KBIO 2011 146 746 1346 KBIO 20 1351 K BIO 2031 1356 Q10DIS 1361 Q10DOC 166 766 1366 11 47 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 First Order Rates day The user may specify first order biodegradation rate constants for water column and benthic segments using constants KBW and KBS If nonzero values are specified for these constants they will be used directly bypassing second order calculations Constant numbers are given in Table 7 19 Second Order Rate __ Coefficients mL cell day The user may specify second order biodegradation rate constants for each phase dissolved DOC sorbed and sediment sorbed and each ionic specie using constant KBIO20 Constant numbers for the neutral molecule are
170. eration rate If Kyo is not provided TOXI will compute the ratio based on the molecular weights of Q and that of the chemical as shown below Equation 11 44 K Kav327 M where My molecular weight of the chemical g mole Under this option the gas transfer rate Ko is calculated using O Conner s method see Option 4 11 22 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 11 6 4 Volatilization Option 3 If this option is specified the liquid film transfer coefficient will be computed as in Option 2 However the gas film transfer coefficient will be computed using Mackay s method see Option 5 11 6 5 Volatilization Option 4 The liquid and gas film transfer coefficients computed under this option vary with the type of waterbody The type of waterbody is specified as one of the volatilization constants and can either be a flowing stream river or estuary or a stagnant pond or lake The primary difference is that in a flowing waterbody the turbulence is primarily a function of the stream velocity while for stagnant waterbodies wind shear may dominate The formulations used to compute the transfer coefficients vary with the waterbody type as shown below a Flowing Stream River or Estuary For a flowing system type 0 the transfer coefficients are controlled by flow induced turbulence For flowing systems the liquid film transfer coefficient Ki is computed using the Covar method Covar 1976 in which
171. ersion Flow Bypass 3 16 3 83 Density 3 16 3 8 4 Maximum Concentration 3 16 3 85 Boundary Load Scale amp Conversion Factor 3 16 3 9 Segmentation Screen _ 1 1 1 3 17 3 9 1 Segment Definition 3 17 3 992 Segment Environmental Parameters 3 19 3 9 3 Initial Concentrations 3 20 3 9 4 Fraction Dissolved 3 21 3 10 Segment Parameter Scale Factors 1 1 3 22 3 11 Dispersion ot ee ee 3 23 3 11 1 Exchange Fields 3 24 3 11 2 Dispersion Function 3 24 3 11 3 Dispersion Time Function 3 25 3 127 SPIOWS Roo o s one doom 8 6d sot ergo s A dir 3 25 3 12 1 Flow Function 3 27 3 12 2 Flow Time Function 3 27 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 3 13 Boundaries _______ 4s tt te Idae C see n 3 27 3 13 1 Boundary Time Function 3 28 SUA Loads 7X ee t 3 28 3 14 1 Load Time Function 3 29 3 15 Loads Scale and Conversion 3 29 3 15 1 Time Step 3 30 3 16 Print Interval 1 0 0 LL 3 31 3 17 Time Functions 2 0 LLL 3 32 3 18 Constants 3 J X Zi 2 24 3 33 3 19 FillCaleulate amp Graphing h 5 J 3 35 3 19 1 Toolbar Definition 3 38 3 20 ValidityCheck 1 3 38 3 21 Model Execution _______ 0 0 0 LL 3 39 4 Visual Graphic Post Processor 4 42 4 1 MainToolbar
172. es not need to keep track of the segments by number alone When you initially insert a segment it is automatically given the name WASP Segment To name segments highlight the cell and type the name for each segment Volumes This column represents the volume of the segment that is being defined The units for volume are cubic meters Note that WASP6 does not assume a cubic formation for a segment the shape is arbitrary Water Velocity Depth There are several options for specifying water velocity and depth to WASP6 Depth and velocity can be held constant by entering their values in the Depth and Velocity multiplier field and setting the exponent to zero The user may also allow depth and velocity to vary as a function of flow To do this the user must provide a depth and velocity multiplier and exponent The velocity m s is computed from the formulation aQ while the depth m is computed from cQ where a amp d are coefficients and Q is the flow m sec Segment Type WASP6 supports four different segment types The user must provide a segment type for each of the segments being defined The segment type dialog box is used to define the segment type for the segment being defined 1 Surface Water Segment any segment that has an interface with the atmosphere Only segment type 1 s have reaereation 2 Sub Surface Water Segment water segment without atmospheric interface 3 Surface Benthic Segment surficial benthic se
173. exchange of sediment and particulate chemicals 7 2 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 7 2 W 5 7 Ag wrSi woS j where Wbs net sediment flux rate g day S sediment concentration g m Wp deposition velocity m day Wp scour velocity m day A benthic surface area m i benthic segment j water segment The deposition velocity can be calculated as the product of the Stokes settling velocity and the probability of deposition Equation 7 3 Wo V sQp where ap probability of deposition upon contact with the bed The probability of deposition depends upon the shear stress on the benthic surface and the suspended sediment size and cohesiveness Likewise the scour velocity depends upon the shear stress the bed sediment size and cohesiveness and the state of consolidation of surficial benthic deposits Figure 7 1 is offered as initial guidance in specifying initial deposition and scour velocities For example coarse silt of 0 05 mm diameter may settle at 100 to 200 m day but should not deposit where mean stream velocity is above 0 5 cm sec Where mean velocity rises above 30 cm sec erosion is expected and nonzero scour velocities should be specified For fine silt of 0 005 mm diameter settling at 1 to 2 m day deposition is not expected even under quiescent conditions Nonzero scour velocities should be specified where mean velocity is above 2 m sec Site specific calibr
174. explicitly The dissolved oxygen processes in EUTRO are discussed in Chapter 8 The CBOD and DO reaction terms are summarized in Table 8 1 9 4 1 Benthic Water Column Interactions The decomposition of organic material in benthic sediment can have profound effects on the concentrations of oxygen and nutrients in the overlying waters The decomposition of organic material releases nutrients to the sediment interstitial waters and also results in the exertion of an oxygen demand at the sediment water interface As a result the areal fluxes from the sediment can be substantial nutrient sources or oxygen sinks to the overlying water column Additionally the occurrence of anoxia due in part to the sediment oxygen demand may dramatically increase 9 26 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 certain nutrient fluxes through a set of complex redox reactions that change the state and concentrations of various nutrients and metals thereby releasing bound nutrients The relative importance of the sediment oxygen demand and nutrient fluxes vis a vis future nutrient control strategies requires the incorporation of a dynamic sediment layer and its associated interactions with the overlying water column in a framework that is consistent with that discussed in the previous sections EUTRO provides two options for nutrient and oxygen fluxes descriptive input and predictive calculations Figure 9 7 The first option is used fo
175. f user specified hydraulic discharge coefficients can be entered in Figure 3 9 that defines the relationship between velocity depth and stream flow in the various segments This method described below follows the implementation in QUAL2E Brown and Barnwell 1987 In WASP6 these segment velocities and depths are only used for calculations of reaeration and volatilization rates they are not used in the transport scheme Discharge coefficients giving depth and velocity from stream flow are based on empirical observations of the stream flow relationship with velocity and depth Leopold and Maddox 1953 It is important to note that these coefficients are only important when calculating reaeration or volatilization The velocity calculations are not used in time of travel and will not affect the simulation of tracers The equations relate velocity channel width and depth to stream flow through power functions Equation 6 1 Hydraulic Coefficients V aQ Equation 6 2 D cQ Equation 6 3 B eQ where D is average depth m 6 4 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 B is average width m a b c d e and f are empirical coefficients or exponents Given that area is a function of average width B and average depth D Equation 6 4 A DB it is clear from continuity that Equation 6 5 Q U A U D Bc aQ e c Q e e Q aecee gr and therefore the following relationships hold Equatio
176. ficient decreases the value of the conductivity tends to be increasingly influenced by the intensity of atmospheric turbulence Because Henrys Law coefficient generally increases with increasing vapor pressure of a compound and generally decreases with increasing solubility of a compound highly volatile low solubility compounds are most likely to exhibit mass transfer limitations in water and relatively nonvolatile high solubility compounds are more likely to exhibit mass transfer limitations in the air Volatilization is usually of relatively less magnitude in lakes and reservoirs than in rivers and streams In cases where it is likely that the volatilization rate is regulated by turbulence level in the water phase estimates of volatilization can be obtained from results of laboratory experiments As discussed by Mill et al 1982 small flasks containing a solution of a pesticide dissolved in water that have been stripped of oxygen can be shaken for specified periods of time The amount of pollutant lost and oxygen gained through volatilization can be measured and the ratio of conductivities KVOG for pollutants and oxygen can be calculated As shown by Tsivoglou and Wallace 1972 this ratio should be constant irrespective of the turbulence in a water body Thus if the reaeration coefficient for a receiving water body is known or can be estimated and the ratio of the conductivity for the pollutant to reaeration coefficient has been measured the
177. for the given WIF any DB or SHP files are automatically read in 3 6 1 New The new project menu item initiates the creation of a new project file The user can add as many of the three accepted file types given above to the project file Once the file has been created and files added the user should use the save function to write the project file to disk 3 9 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 3 6 2 Open This menu item allows the user to open a previously created project file Once open is selected the user is given a standard Windows file dialog box Note that project files have the extension of WWP 3 6 3 Edit The edit menu item allows the user to modify the contents of the opened project file The users can remove add files to the project 3 6 4 Save The save function writes the project file information to disk When this option is selected the file is written without user intervention 3 6 5 Save as The Save as function allows the user to save the previously loaded project file to another filename This is useful when conducting sensitivity analysis and do not want to lose the initial project When the user selects the Save as function they are presented with a standard Windows file dialog box 3 10 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Project C winwasp E xample st shp C winwasp Example wasp shp C winwasp E xample tampa bmg C
178. g through direct and diffuse loading advective and dispersive transport and physical chemical and biological transformation Consider the coordinate system shown in Equation 5 1 where the x and y coordinates are in the horizontal plane and the z coordinate is in the vertical plane 5 1 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Water Quality Equation Figure 5 1 Coordinate System for Mass Balance Equation The mass balance equation around an infinitesimally small fluid volume is Equation 5 1 General Mass Balance Equation d d 9 eH ur ec E C U C 34 Us ag Os 3 U g TC SU AES E 2 Sit SetSx where C concentration of the water quality constituent mg L or g m t time days U U U longitudinal lateral and vertical advective velocities m day E E E longitudinal lateral and vertical diffusion coefficients m day S direct and diffuse loading rate g m day Sg boundary loading rate including upstream downstream benthic and atmospheric g m day Sk total kinetic transformation rate positive is source negative is 5 2 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 sink g m day By expanding the infinitesimally small control volumes into larger adjoining segments and by specifying proper transport loading and transformation parameters WASP implements a finite difference form of Equation 5 1 For brevity and clarity h
179. ganic nitrogen mineralization rate constant day E427 temperature coefficient k average phytoplankton growth rate constant day user must input light and nutrient limited value E temperature coefficient f organic nitrogen dissolved fraction Constant phytoplankton concentrations to be used in the DO balance are input under initial conditions as ug L chlorophyll a If the carbon to chlorophyll ratio is not input then a default value of 30 is used The particulate fractions of CBOD and ON are associated with transport field 3 organic matter settling 8 5 1 Environment Parameters These parameters define the basic model identity including the segmentation and control the simulation Systems Select simulate for NH3 NO3 CBOD DO and ON Select constant for PHYT and bypass for PO4 and OP Segments Water column segments should be defined in the standard fashion If CBOD or ON settling is to be simulated the user should add a single benthic segment underlying all water column segments This benthic segment will merely act as a convenient sink for settling organic matter Model calculations within this benthic segment should be ignored 8 5 2 Transport Parameters This group of parameters defines the advective and dispersive transport of model variables Number of Flow Fields To simulate settling the user should select solids 1 flow under advection The user should also select water column flow 8 24 D
180. gment 3 18 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 4 Sub Surface Benthic Segment all benthic segments below surface benthic segments Bottom Segment The bottom segment is used to define which segment is below the currently being defined segment If the segment does not have a segment below it the bottom segment should be set to none or zero The bottom segment definition is used to define the optical light path it is not used in transport calculations 3 9 2 Segment Environmental Parameters This table contains segment specific environmental parameters These parameters are different for the various WASP6 model types The segment parameter information interacts directly with the Parameter Scale Factor screen The user only needs to provide information for the environmental parameters that are going to be considered in the simulation Some parameters are used to directly define segment specific information i e SOD others are used to point to environmental time functions i e Temperature The pointers to environmental time functions allow the user to define spatial and temporal variation for segment parameters such as temperature water velocity pH and bacteria concentration 3 19 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WIN WASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO File Project Pre processor Model Post Processor Help
181. gmentation Schematic Segments in WASP may be one of four types as specified by the input variable ITYPE A value of 1 indicates the epilimnion surface water 2 indicate hypolimnion layers subsurface 3 indicate an upper benthic layer and 4 indicate lower benthic layers The segment type plays an important role in bed sedimentation and in certain transformation processes The user should be careful to align segments properly The segment immediately below each segment is specified by the input variable IBOTSG This alignment is important when light needs to be passed from one segment to the next in the water column or when material is buried or eroded in the bed Segment volumes and the simulation time step are directly related As one increase or decreases the other must do the same to insure stability and numerical accuracy Segment size can vary dramatically as illustrated in Figure 5 3 Characteristic sizes are dictated more by the spatial and temporal scale of the problem being analyzed than by the characteristics of the water body or the pollutant per se For example analyzing a problem involving the upstream tidal migration of a pollutant into a water supply might require a time step of minutes to an hour By contrast analyzing a problem involving the total residence time of that pollutant in the same water body could allow a time step of hours to a day The first network was used to study the general eutrophic status of Lake Ontario Th
182. gned to each segment with the particulate and dissolved inorganic phosphorus computed for each time step in a manner similar to the overlying water column inorganic phosphorus Equation 9 26through Equation 9 30 Exchange of the 9 30 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 dissolved phosphorus forms with the overlying water column is also similar to that of ammonia nitrate and dissolved oxygen Mass flux equations are presented in Figure 9 8 The effects of anoxia upon sediment phosphorus flux were not included in the modeling framework The approach used to generate sediment phosphorus flux although not entirely satisfactory is at least consistent with the framework within which the fluxes of other materials are being generated Benthic Carbon The reactions that convert algal and refractory carbon to their end products are complex The initial step in which the algal and refractory carbon are converted to reactive intermediates appears to be similar to the refractory organic and algal nitrogen degradation and in the subsequent calculations the rates for carbon and nitrogen decomposition are assumed to be equal The reactive intermediates however participate in further reactions for example volatile acids react to become methane and the mechanisms that control these reactions are somewhat uncertain In addition few measurements of these intermediate species are available and a calculation that incorporates
183. gr ld ree XY Parameters Figure 4 12 Y Axis Labeling Secondary Range Label This dialog box is used to describe the label that will be displayed above the y axis on the graph The y axis is the one on the right hand side of the graph and is typically is used for concentration 4 61 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 E Post processor x File View Window Help ay ZEE Parameters Curves General Domain Primary Range Secondary Range Label Et Restrict Range Minimum omm y Maximum pom u Se CAPS NUM OVA AMStart SS A Y Paint Shop Fro mageti E Postprocessor EE 224Pm Figure 4 13 Secondary Y Axis Labeling Time Segment This radio button option is used to inform that the xaxis domain is going to be used for time or distance If the user selects distance another option is available for the x axis domain definition that is described below Map Segment to Distance If the user selects the x domain to be of type segment the user has the option of mapping the segment number to that of a river mile or distance If this option is selected the user will need to create a database file that has the segment number with its corresponding distance When this option is properly configured the distance and its corresponding concentration will appear on the x y plot Restrict Domain By default the x axis is automatically scaled using built in heuris
184. hains of redox reactions occurring in the sediment Figure 8 4 8 12 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Carbonaceous Biochemical Oxygen Demand a ocker Porm T 79 C4 ke Oot 770 Cs 4 Z kiad Cy E fin Ca ma fos Cs Tren Cs fos Decomporition Oridaton Denitrification fetting tora porbn Du ffwin Dissolved Oxygen ace j pas LEIP T a kno pei Caz Ondilation Diffvion Sediment Oxygen Demand g m day SOD ca Cj For benthic cu gmentj wata co gnati Figure 8 4 Benthic layer oxygen balance equations Because the calculated concentration of oxygen is positive in the overlying water it is assumed that the reduced carbon species negative oxygen equivalents that are transported across the benthic water interface combine with the available oxygen and are oxidized to CO and H2O with a consequent reduction of oxygen in the overlying water column Table 8 2 summarize the benthic CBOD and DO reactions and parameters Illustrative parameter values from an early Potomac Estuary modeling study are provided Table 8 2 Benthic Layer CBOD and DO Reaction Terms Description Notation Value Units Organic carbon as CBO D decomposition rate kps 0 0004 day Temperature coefficient Eps 1 08 none Denitrification rate kop day Temperature coefficient E2 none Phytoplankton decomposition rate kpzp day 1 8 13 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Des
185. he boundary concentration accompanying the inflow If a large number of diffuse loads are being read in the user can provide for the incremental flows using a flow continuity function that increases downstream 6 2 8 Nonpoint Source Linkage Realistic simulations of nonpoint source loadings can be accomplished by linking WASP6 to a compatible surface runoff simulation This linkage is accomplished through a formatted external file chosen by the user at simulation time The nonpoint source loading file contains information on which WASP6 systems and segments receive nonpoint source loads and a record of the nonzero loads by system segment and day If the user sets the nonpoint source loading flag by checking the dialog box in Figure 3 6 a menu of previously prepared nonpoint source files NPS is presented Following the choice of a proper file nonpoint source loads are read once a day throughout a simulation from a loading file generated by a previous loading model simulation These loads are treated as gep functions that vary daily When the user implements the nonpoint source loading option model time steps should be divisible into 1 day Time steps do not have to be exactly divisible into a day if time steps are small any errors associated with carrying the previous day s loading rate into a new day will be small The external nonpoint source load file is a formatted ASCII file chosen by the user This file contains information on w
186. he past history of the phytoplankton population Large ratios of carbon to nitrogen or phosphorus correspond to that nutrient limiting growth small ratios reflect excess nutrients Thus the choice of the relevant ratios can be made with the specific situation in mind The operational consequence of this choice is that the population stoichiometry under non limiting conditions may be underestimated but under limiting conditions should be estimated correctly Hence the trade off is a probable lack of realism during a portion of the year versus a correct estimate of phytoplankton biomass during periods of possible nutrient limitations Because this is usually the critical period and because most questions to be answered 9 15 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 are usually sensitive to maximum summer populations this choice is a practical expedient A comparison of carbon to nitrogen and carbon to phosphorus ratios measured in the Potomac Estuary is provided in Table 9 3 Table 9 3 Carbon to nitrogen carbon to phosphorus ratios Phosphorus Carbon mg Nitrogen Carbon P mgC mg N mg C Sampling Period Observed Observed Observed Observed Mean Range Mean Range July 20 0 ct 6 1970 0 023 0 010 0 046 0 26 0 10 0 48 August 1 29 19772 0 024 0 012 0 028 0 24 0 15 0 36 Sept 7 28 19782 0 030 0 017 0 047 0 26 0 18 0 35 Sept 7 28 19782 0 031 0 26 Model 0 025 0 25 1 Elemental analysis of blue green algae 2 La
187. he product of the variable zooplankton population and the unit grazing rate Note that ZOO can also be expressed as cells L if K1G is expressed as L cell day Phosphorus to Carbon Ratio mg P mg C The average phosphorus to carbon weight ratio in phytoplankton can be specified using constant PCRB The EUTRO default value for PCRB is 0 025 Phytoplankton Phosphorus Recycle The fraction of dead and respired phytoplankton phosphorus that is recycled to the organic phosphorus pool can be specified using constant FOP The default value is 1 The fraction of phytoplankton phosphorus recycled directly to inorganic phosphorus is 1 FOP Phosphorus Mineralization Rate day The mineralization rate constant and temperature coefficient for dissolved organic phosphorus can be specified using constants K83C and K83T respectively Phytoplankton effects on mineralization can be described using constant KMPHY the half saturation constant for mineralization dependence on phytoplankton in mg C L This causes mineralization rates to increase as phytoplankton levels increase If KMPHY is zero there is no phytoplankton effect on mineralization If KMPHY is large then large concentrations of phytoplankton are needed to drive mineralization and thus relatively low phytoplankton levels can lead to low mineralization rates Benthic Phosphorus Flux mg m day The segment and time variable benthic phosphorus flux can be specified using parameter FPO4 and ti
188. he sediment TOXI provides several optional methods for the description or computation of the partition coefficients These options are identified by the data input as described below 11 5 3 X Option 1 Measured Partition Coefficients This option allows the user to directly input a partition coefficient Separate partition coefficients may be input for each of the three solids types The partition coefficient is input in units of L kg not in log units 11 5 4 Option 2 Input of Organic Carbon Partition Coefficient Normalization of the partition coefficient by the organic carbon content of the sediment has been shown to yield a coefficient Koc the organic carbon partition coefficient that is relatively independent of other sediment characteristics or geographic origin Many organic pollutants of current interest are non polar hydrophobic compounds whose partition coefficients correlate quite well with the organic fraction of the sediment Rao and Davidson 1980 and Karickhoff et al 1979 have developed empirical expressions relating equilibrium coefficients to laboratory measurements leading to fairly reliable means of estimating appropriate values The correlations used in TOXI are Equation 11 36 K ps0 f ocs K 26 Equation 11 37 K 57 1 0 K o where 11 15 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Ky organic carbon partition coefficient L kg m organic carbon fraction of sedime
189. he user has the ability to select which of the model results files to display Each spatial analysis grid can display only one model result file To select a currently loaded dataset to display in the current spatial analysis grid press the Configuration Button and select the drop down picklist for Data Set This will make the results from the selected file appear in the spatial grid Note The spatial grid analysis can only display information from one model result file ata time The user has the option of creating as many spatial analysis grid windows as needed 4 5 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 4 3 7 Selecting Slice Geometry The Binary Model Geometry BMG file is selected from the geometry drop down picklist A BMG file can contain more than one view slice of the model network A slice is simply a set of polygons that are assigned t a set of cross sections A BMG file can contain more than one slice and is created during the Digitize development To select a slice that is contained within the BMG file select the slice name from the drop down selection from the configuration screen 4 3 8 Selecting Variable The user has the ability to select any one of the simulation result variables that is written to the output file by the execution of the WASP models The model result file EUTRO or TOXI will determine the variables that are available for display To select a variable for a selected
190. hic segments underlying a water column segment representing discrete benthic deposits or habitats The concentration of chemical diffusing is the dissolved fraction per unit pore water volume The actual diffusive exchange between benthic segments i and j at time t is given by Equation 6 10 9M Es t Auns fC r f ouCa ETE Lal ni nj ni where facto dissolved fraction of chemical k in segments i and j n average porosity at interface ij L L E t diffusion coefficient time bein for cael ij m day Aj interfacial area shared by segments i and j Lj characteristic mixing length between oma i and j 6 2 6 Boundary Processes A boundary segment is characterized by water exchanges from outside the network including tributary inflows downstream outflows and open water dispersive exchanges WASP6 determines its boundary segments by examining the advective and dispersive segment pairs specified by the user If an advective or dispersive segment pair includes segment number 0 the other segment number is a boundary segment Thus for advective flows the segment pair 0 1 denotes segment 1 as an upstream boundary segment segment pair 5 0 denotes segment 5 as a downstream boundary segment Boundary concentrations Cgix mg L must be specified for each simulated variable k at each boundary segment i These concentrations may vary in time At upstream boundary segments WASP6 applies the following mass loading r
191. hich WASP systems and segments receive nonpoint source loads and a record of the nonzero loads by system segment and day Six records comprise the nonpoint source file Nonpoint Source File Format Line 1 NPSMOD Name or description of nonpoint source model or method of generation this is echoed to the output file for the record A15 NUMSEG Number of segments receiving nonpoint source loads I5 INTOPT Interpolation option 1 step function only one in code now I5 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 NUMSYS Number of WASP systems receiving nonpoint source loads I5 Record 2 Loading Segments 15 LSEG I segment number receiving loads I5 Record 2 is repeated NUMSEG times Record 3 Loading Systems 20I5 LSYS I WASP system numbers receiving loads I5 Record 4 System Descriptors A15 NAMESY I Name or description of WASP systems receiving loads A15 Record 4 is repeated NUMSYS times Records 5 and 6 are repeated as a unit for the number of days that nonzero loads occur Record 5 Loading Days F10 0 LDAY Time in days for the following nonzero load F10 0 Record 6 Nonpoint Source Loads A15 20F10 0 NAMESY System name or description not read in by WASP A15 NPSWK LJ Nonpoint source loads for WASP system I at all loading segments J in the order presented in Record 2 Loads are in kg day 20F10 0 Record 6 is repeated NUMSYS times
192. ial Conditions Loads 3 7 3 Comments The dialog box provides space for the user to annotate important information about the dataset The model does not need this information 3 12 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 3 7 4 Restart Options WASP6 provides the user with the ability to use restart files between simulation runs A restart file is a snap shot of the model conditions at the end of the simulation This snap shot can be used as the initial conditions for a future model run Note that the future model run must be of the same model type and segmentation scheme There are three options for Restart 1 No Restart File WASP6 does not create a restart file default 2 Create Restart File WASPS creates a restart file that contains the final volumes and concentrations for each of the segments and systems 3 Create Read Restart File WASP6 creates a file as described above but reads initial volumes and concentrations from a previously created restart file 3 7 5 Date and Times The previous versions of WASP did not require that the model time functions be represented in Gregorian date format The Version 6 00f WASP requires all time functions be represented in Gregorian fashion mm dd yr hh mm ss The user in the Start Time dialog box must specify the starting date and time This date and time correspond to time zero in the old version of the model 3 7 6 Non Point Source File
193. ibed to the model are provided in Table 7 2 Parameter or Time Time Affected Kinetic Function Units Variable Processes Water Temperature mc Dissolved Organic NES L NE LUN PME Carbon Fraction Organic none Sorption Carbon pH Y Hydrolysis Bacterial Concentration Biodegradation Extra Property Hacc NE Extra 2nd Order Reaction Wind Velocity m sec Volatilization DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Air Temperature oC Y Volatilization Chlorophyll a mg L Y Photolysis Concentration Normalized Light None Photolysis Option 2 Intensity Only 11 1 TOXI Reactions and Transformations In an aquatic environment an organic chemical may be transferred between phases and may be degraded by any of a number of chemical and biological processes Ionization may speciate the chemical into multiple forms Transfer processes defined in the model include sorption and volatilization Defined transformation processes include biodegradation hydrolysis photolysis and chemical oxidation Sorption and ionization are treated as equilibrium reactions All other processes are described by rate equations Rate equations may be quantified by first order constants or by second order chemical specific constants and environment specific parameters that may vary in space and time WASP6 uses a mass balance equation to calculate sediment and chemical mass and concentrations for every segment in a specialized netwo
194. ic Nitrogen Simulated FE Fl Fl 0 00 0000000 00 1 00 8 Organic Phosphorous Simulated m mM m 0 00 0000000 00 1 00 2j IT Fica EEG DEEP SIE ee eee Mstart E 2 A X 8 Paint Shop Pro Imeget3 E ASci WIN WASP Bl amp 10254M Figure 3 7 WASP6 System Bypass and Global Scale Factors 3 8 1 System Options There are three options for this field Simulated Constant and Bypassed The user can select which of the system options by selecting the option from the drop down dialog box for each individual system e Simulated indicates to WASP that the user wants the model to calculate all equations associated with that state variable every time step This is the most common selection e Constant indicates to WASP that the user wants to hold the mass of this system constant and not allow the equations pertaining to this system to be calculated but allow its mass to influence the rates and fate of the other system s that can be affected by the presence of this systems mass An example would be to include the influence of algae on dissolved oxygen without simulating the dynamics of algae The user would provide initial concentrations for algae that would never change and enter rate constants for respiration and oxygen production This would simulate a steady state effect of algal influences on 3 15 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 dissolved oxygen without providing all the info
195. ic layer is to determine its depth Two factors influence this decision The first is to adequately reflect the thickness of the active layer the depth to which the sediment is influenced by exchange with the overlying water column Secondly one wishes the model to reflect a reasonable time history or memory in the sediment layer Too thin a layer and the benthos will remember or be influenced by deposition of material that would have occurred only within the last year or two of the period being analyzed too thick a layer and the model will average too long a history not reflecting substantial reductions resulting from reduced discharges from sewage treatment plants The choice of sediment thickness is further complicated by spatially variable sedimentation rates The benthic layer depths together with the assigned sedimentation velocities provide for a multi year detention time or memory providing a reasonable approximation of the active layer in light of the observed pore water gradients The decomposition reactions that drive the component mass balance equations are the anaerobic decomposition of the phytoplankton carbon and the anaerobic breakdown of the benthic organic carbon Both reactions are sinks of oxygen and rapidly drive its concentration negative indicating that the sediment is reduced rather than oxidized The negative concentrations computed can be considered the oxygen equivalents of the reduced end products produced by the c
196. ied for any segment receiving flow inputs outputs or exchanges Initial conditions include not only initial concentrations but also the density and solids transport field for each solid and the dissolved fraction in each segment Boundary Concentrations mg L At each segment boundary time variable concentrations must be specified for BOD and DO A boundary segment is characterized by water exchanges from outside the network including tributary inflows downstream outflows and open water dispersive exchanges Figure 3 15 Waste Loads kg day For each point source discharge time variable BOD and DO loads can be specified These loads can represent municipal and industrial wastewater discharges or urban and agricultural runoff Figure 3 16 Solids Transport Field The transport field associated with particulate BOD settling must be specified under initial conditions Field 3 is recommended Figure 3 14 Solid Density g cm A value of 0 can be entered for the nominal density of BOD and DO This information is not used in EUTRO Figure 3 10 Initial Concentrations mg L Concentrations of BOD and DO in each segment must be specified for the time at which the simulation begins Concentrations of zero for nonsimulated variables NH3 NO3 PO4 PHYT ON and OP will be entered by the preprocessor Figure 3 10 Dissolved Fraction The dissolved fraction of BOD and DO in each segment must be specified Values for DO should be 1
197. iently detailed to specify the growth kinetics for individual algal species in a natural environment Rather than considering the problem of different species and their associated environmental and nutrient requirements this model characterizes the population as a whole by the total biomass of the phytoplankton present A simple measure of total biomass that is characteristic of all phytoplankton chlorophyll a is used as the aggregated variable The principal advantages are that the measurement is direct it integrates cell types and ages and it accounts for cell viability The principal disadvantage is that it is a community measurement with no differentiation of functional groups e g diatoms blue greens also it is not necessarily a good measurement of standing crop in dry weight or carbon units because the chlorophyll to dry weight and carbon ratios are variable and non active chlorophyll phaeopigments must be measured to determine viable chlorophyll concentrations As can be seen from the above discussion no simple aggregate measurement is entirely satisfactory From a practical point of view the availability of extensive chlorophyll data essentially dictates its use as the aggregate measure of the phytoplankton population or biomass for calibration and verification purposes For internal computational purposes however EUTRO uses phytoplankton carbon as a measure of algal biomass Using either a fixed or variable carbon to chlorophyll m
198. ified These nutrient concentrations will remain constant throughout the simulation and can affect PHYT through growth rate limitation although nonsimulated 9 35 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 nutrients should be in excess and therefore not affect growth Concentrations of zero for bypassed variables CBOD and DO will be entered by the preprocessor Dissolved Fraction The dissolved fraction of PHYT ON NH3 NO3 OP and PO4 in each segment must be specified The dissolved fraction of PHYT should be set to 0 Only the particulate fractions of the nutrients will be subject to settling 9 6 4 Transformation Parameters This group of parameters includes spatially variable parameters constants and kinetic time functions for the water quality constituents being simulated Parameter values are entered for each segment Specified values for constants apply over the entire network for the whole simulation Kinetic time functions are composed of a series of values versus time in days Water Temperature C Time and segment variable water temperatures can be specified using the parameters TMPSG and TMPEN and the time functions TEMP 1 4 If temperatures are to remain constant in time then the user should enter segment temperatures using the parameter TMPSG TMPEN and TEMP 1 4 should be omitted If the user wants to enter time variable temperatures then values for the parameter TMPSG should be set
199. ile type that is used is the binary model geometry file This file is used to provide the spatial grid geometry information so that the model results can be depicted within the model grid 4 2 1 Opening Model Output Prior to working with any model data or observed data the files must be selected by the user There is no limit to the number of files that can be opened If the user would like to open additional files the procedure given below will illustrate how to load each of the different file types To open a file the user can use the menu system and select open file or press the open file icon This will display a file dialog box as illustrated in Figure 4 1 From this file dialog box the user can navigate to any drive and directory to which their computer is attached By pressing the down arrow on the file type dialog a list of valid file extensions is displayed for the user Selecting an extension will result in the display of a picklist of the available files in the current drive and directory 4 43 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 EA Post processor File View Window Help a Look jn 3 winwasp J El al ek wl database examples river ai example wwp Postmap a river wwp Femme 7 Files of type Supported File Types Supported File Types Win Wasp Projects wwP Binary Data Files BMD Binary Geometry Files BMG Shape Files SHP Observed Data Tables D
200. iley et 4 1949 and is determined via Equation 5 13 Equation 9 13 k ir T k 1r 20 C Ole where k 20 C the endogenous respiration rate at 20 C day ka T the temperature corrected rate day Eg temperature coefficient dimensionless Reported values of endogenous respiration at 20 vary from 0 02 day to 0 60 day with most values falling between 0 05 day and 0 20 day Bowie et al 1985 Di Toro and Matystik 1980 report a value of 1 045 for Eig The total biomass reduction rate for the phytoplankton in the jth segment is expressed via Equation 5 14 Equation 9 14 D ij k rl k ip k ic Lt where Dj biomass reduction rate day kp death rate representing the effect of parasitization i e the infection of algal cells by other microorganisms and toxic materials such as chlorine residual day k grazing rate on phytoplankton per unit zooplankton population L mgC day Z t herbivorous zooplankton population grazing on phytoplankton mgC L Note that the zooplankton population dynamics are described by the user not simulated If population fluctuations are important in controlling phytoplankton levels in a particular body of water the user may want to simulate zooplankton and their grazing On the other hand many studies need only a constant first order grazing rate constant where grazing rates are assumed proportional to phytoplankton levels In that case kg can be set to the first order con
201. imulation Program WASP Version 6 0 porosities are recalculated every benthic time step If the variable bed volume is chosen upper benthic segment volumes are updated every time step with compaction occurring every benthic time step Figure 3 6 Transport Parameters Sediment Transport Velocities _m sec Time variable settling deposition scour and sedimentation velocities can be specified for each type of solid If the units conversion factor is set to 1 157e 5 then these velocities are input in units of m day These velocities are multiplied internally by cross sectional areas and treated as flows that carry solids and sorbed chemical between segments Settling velocities are important components of suspended sediment transport in the water column Scour and deposition velocities determine the transfer of solids and sorbed chemical between the water column and the sediment bed Sedimentation velocities represent the rate at which the bed is rising in response to net deposition Figure 3 14 Cross Sectional Areas m The interfacial surface area must be specified for adjoining segments where sediment transport occurs These surface areas are multiplied internally by sediment transport velocities to obtain sediment transport flows Figure 3 14 7 2 3 Boundary Parameters This group of parameters includes boundary concentrations waste loads and initial conditions Boundary concentrations must be specified for any segment r
202. iodegradation rate constants from other aquatic systems are used directly 11 45 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 11 10 1 Overview of TOXI Biodegradation Reactions In TOXI first order biodegradation rate constants or half lives for the water column and the benthos may be specified If these rate constants have been measured under similar conditions this first order approach is likely to be as accurate as more complicated approaches If first order rates are unavailable or if they must be extrapolated to different bacterial conditions then the second order approach may be used It is assumed that bacterial populations are unaffected by the presence of the compound at low concentrations Second order kinetics for dissolved DOC sorbed and sediment sorbed chemical are considered Equation 11 70 K w Py 0 Y kauf i j 1 2 i j Equation 11 71 K ss Pcl Y kefy j73 i j where Ks net biodegradation rate constant in water day Ky net biodegradation rate constant on sediment day second order biodegradation rate constant for specie i phase j ml cell day active bacterial population density in segment cell ml fraction of chemical as specie i in phase j ks Past y In TOXI the biodegradation rate may be adjusted by temperature as shown below Equation 11 72 k pi T k Bij Q oe where Qn Q 10 temperature correction factor for biodegradation of specie i phase j T
203. ion Diffusive pore water exchanges can significantly influence benthic pollutant concentrations particularly for relatively soluble chemicals and water bodies with little sediment loading Depending on the dissolved concentration gradient pore water diffusion may be a source or sink of pollutants for the overlying water column If benthic segments are included in the model network the user may specify diffusive transport of dissolved chemicals in the pore water In WASP6 pore water diffusion is input via transport field two in Figure 3 13 The user may define several groups of exchanges For each exchange group the user must supply a time function giving dispersion coefficient values in m sec as they vary in time For each exchange in the group the user must supply an interfacial area a characteristic mixing length and the segments between which exchange takes place The characteristic mixing length is typically the distance between two benthic segment midpoints multiplied internally by the tortuosity which is roughly the inverse of porosity For pore water exchange with a surface water segment the characteristic mixing length is usually taken to be the depth of the surficial benthic segment The interfacial area is the surficial area of the benthic segment which is input by the user multiplied internally by porosity 6 8 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 There may be several surficial bent
204. ion Langleys day F1 1 00 Measured Segment Reareation Rate per 7 1 00 Zooplankton Population E 1 00 Percent Light Intercept by Canopy m 1 00 Fil Cal X Cancel start E 2 pU B Paint Shop Pio maget4 e ASci WIN WASP EE 10304M Figure 3 12 Segment Parameter Scale Factors 3 11 Dispersion The dispersion input screen is a complex screen that contains four tables Under dispersion the user has a choice of up to two exchange fields To simulate surface water toxicant and solids dispersion the user selects water column dispersion in the preprocessor or sets the number of exchange fields to one To simulate exchange of dissolved toxicants within the bed the user should also select pore water diffusion in the preprocessor or set the number of exchange fields to two 3 23 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WIN WASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO File Project Pre processor Model Post Processor Help Df as ese ae lL Rel ot IO el C N la cl Exchange Fields Surface Water functions Field Scale Conversion Function Suface Water 1 0000 1 0000 Exchange Function Pore Water 1 0000 1 0000 Exchange Function Exchange Function Exchange Function Exchange Function Exchange Function zi Fil Calc i Insert 7 Delete Segment pairs for Surface Water Exch
205. ion of Algal Death tt 2 Maximum Light Intensity t fe 2 Air Temperature was 0 5 O mro re Ww B Modal Ended Nomalp 3 2 1985 12 00 AM 4 1 1985 12 00 AM E gt Result File Closed E gt Closing Simulation Result 5 1 1985 12 00 AM 5 31 1985 12 00 AM a m m L sans amar Figure 3 23 Column Fill Calculate Option WASP6 also allows the user to plot time series data from any of the appropriate tables To plot a time series press the plot button 3 36 Version 6 0 DRAFT Water Quality Analysis Simulation Program WASP a galala a I Astan 4 i z 3 ind m T5 al 5 3S Q o 8 e im E e n Q T 5 un B wt e Figure 3 the user should place the cursor To zoom the xaxis hold down the left mouse button and drag the box to the The user can zoom the x and yaxis at the starting point of the zoom right to select the full area to zoom Zooming the y axis is done the same way except using the right mouse and dragging down 3 37 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Ec e eceecectcmemaccttib ed 1 1 J 1 1 1 2 ET 1 4 1 1 i ee eee ee ee ee eee Figure 3 25 Graphing Zoom Option 3 19 1 Toolbar Definition The user is provided a toolbar at the bottom left hand corner of the graph window This toolbar provides basic control over the g
206. is step depends on the skill of the user who must combine specialized knowledge with common sense and skepticism into a methodical process The final step answers the question of how this material is likely to affect anything of interest such as people fish or the ecological balance Often predicted concentrations are simply compared with water quality criteria adopted to protect the general aquatic community Care must be taken to insure that the temporal and spatial scales assumed in developing the criteria are compatible with those predicted by the model Sometimes principles of physical chemistry or pharmacokinetics are used to predict chemical body burdens and resulting biological effects The bioaccumulation model FGETS Barber et al 1991 and the WASTOX food chain model Connolly ad Thomann 1985 are good examples of this 5 9 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 6 Chemical Tracer Transport A chemical tracer is a nonreactive chemical that is passively transported throughout the water body Examples include salinity or chlorides Special dyes are used as tracers although these often decay at a slow rate Setting up and calibrating a tracer is the first step in simulating more complex water quality variables 6 1 Overview of WASP6 Tracer Transport A conservative tracer is generally simulated using the TOXI program TOXI simulates the transport and transformation of one to three chemicals and on
207. is the assumption of reversibility Laboratory data for very hydrophobic chemicals suggest however that a hysteresis exists with desorption being a much slower process than adsorption Karickhoff suggests that this effect may be the result of intraparticle kinetics in which the chemical is slowly incorporated into components of the sorbant This phenomenon is not well understood and no quantitative modeling framework is available to characterize it 10 5 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Values for the partition coefficients can be obtained from laboratory experiments or field data TOXI allows the input of either a single constant partition coefficient or a set of spatially variable partition coefficients These options are described under Model Implementation below The calculation of partition coefficients for organic chemicals is described in Chapter 7 10 3 Transformations and Daughter Products The three chemicals that may be simulated by TOXI may be independent or they may be linked with reaction yields such as a parent compound daughter product sequence Linked transformations may be implemented by simulating two or three chemicals and by specifying appropriate yield coefficients for each process Equation 10 9 Su KicC eV C 2 3 n Equation 10 10 Su Y Ke Yes CLI 2 Equation 10 11 Susi y KuCiYus 352 k c where Sum production of chemical i from chemical c undergoing reaction k
208. isted in Di Toro et al 1983 The flexibility afforded by the Water Quality Analysis Simulation Program is unique WASP6 permits the modeler to structure one two and three dimensional models allows the specification of time variable exchange coefficients advective flows waste loads and water quality boundary conditions and permits tailored structuring of the kinetic processes all within the larger modeling framework without having to write or rewrite large sections of computer code The two operational WASP6 models TOXI and EUTRO are reasonably general In addition users may develop new kinetic or reactive structures This however requires an additional measure of judgment insight and programming experience on the part of the modeler The kinetic subroutine in WASP denoted WASPB is kept as a separate section of code with its own subroutines if desired 3 1 Overview of the WASP6 Modeling System The WASP6 system consists of two stand alone computer programs DYNHYDS and WASP6 which can be run in conjunction or separately The hydrodynamics program DYNHYDS simulates the movement of water while the water quality program WASP6 simulates the movement and interaction of pollutants within the water While DYNHYDS is delivered with WASP6 other hydrodynamic programs have also been linked with WASP RIVMOD handles unsteady flow in one dimensional rivers while 3 3 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0
209. ith dissolved chemical concentration Karickhoff 1984 or Equation 11 18 C Kps Cw 11 11 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 At equilibrium then the distribution among the phases is controlled by the partition coefficients Kp The total mass of chemical in each phase is controlled by Kps and the amount of solid phase present including any DOC phase In addition to the assumption of instantaneous equilibrium implicit in the use of equation 7 19 is the assumption of reversibility Laboratory data for very hydrophobic chemicals suggest however that a hysteresis exists with desorption being a much slower process than adsorption Karickhoff suggests that this effect may be the result of intraparticle kinetics in which the chemical is slowly incorporated into components of the sorbant This phenomenon is not well understood and no quantitative modeling framework is available to characterize it 11 5 1 Overview of TOXI Sorption Reactions Dissolved chemical in water column and benthic segments interacts with sediment particles and dissolved organic carbon to form five phases dissolved DOC sorbed and sediment sorbed three sediment types s The reactions can be written with respect to unit volume of water Equation 11 19 M C 9C n Equation 11 20 B DE C e C B n where n is the porosity volume of water divided by total volume The forward reaction is sorption and the backward reac
210. kes no direct assumptions as to the formation of the ionic species or their reactivity The user controls the formation by specification of model input A chemical being modeled by TOXI is presumed to exist as neutral molecules that may or may not react with water molecules to form singly and possibly doubly charged cations and anions To illustrate an organic acid A may react with water as described by Equation 11 1 AH tH O AH OH Equation 11 2 AHS H O AHT OH DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 11 3 AH2 H20_AH H 30 Equation 11 4 AH H O A H5O so that the chemical may exist in from one to a maximum of five species simultaneously A7 AH AH AH3 AH4 The law of mass action can be used to describe local chemical equilibrium for each of these reactions Equation 11 5 _ LAH ILOH 1 AH bi Equation 11 6 _ AH I OH I E AH i Equation 11 7 LAH II H1 T AH 5 Equation 11 8 LA IIH 7 is AH where K is the qquilibrium constant for the formation of the acid Kai or anionic species or the base Kyi or cationic species The total concentration of the particular chemical is the sum of the concentration of each of these forms as given by DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 11 9 C AH AH AH7 AH A which may be combined with the law of mass action to form Equation 11 10
211. l Protection Agency Gulf Breeze FL and Duluth MN Covar A P 1976 Selecting the Proper Reaeration Coefficient for Use in Water Quality Models Presented at the U S EPA Conference on Env Simulation and Modelling Covar A P 1976 Selecting the Proper Reaeration Coefficient for Use in Water Quality Models Presented at the U S EPA Conference on Environmental Simulation Modeling April 19 22 1976 Cincinnati Ohio Di Toro D M D J O Connor and R V Thomann 1971 A Dynamic Model of the Phytoplankton Population in the Sacramento San Joaquin Delta Adv Chem Ser 106 Am Chem Soc Washington DC pp 131 180 Di Toro D M and J P Connolly 1980 Mathematical Models of Water Quality in Large Lakes Part 2 Lake Erie EPA 600 3 80 065 pp 90 101 Di Toro D M and W F Matystik 1980 Mathematical Models of Water Quality in Large Lakes Part 1 Lake Huron and Saginaw Bay EPA 600 3 80 056 pp 28 30 Di Toro D M J J Fitzpatrick and R V Thomann 1981 rev 1983 Water Quality Analysis Simulation Program WASP and Model Verification Program MVP Documentation Hydroscience Inc Westwood NY for U S EPA Duluth MN Contract No 68 01 3872 Di Toro D M 1985 A Particle Interaction Model of Reversible Organic Chemical Sorption Chemosphere 14 10 1503 1538 Eppley R W and P R Sloane 1966 Growth Rates of Marine Phytoplankton Correlation with Light Absorption by Cell Chlorophyll a Physiol Plant 19 47 59
212. l chemical Acid Catalyzed Hydrolysis Rate Constants M day The user may specify second order acid catalyzed hydrolysis rate constants for each phase dissolved DOC sorbed and sediment sorbed and each ionic specie using constant KH20 Constant numbers for the neutral molecule are summarized in Table 7 11 KH2031 1 refers to the dissolved neutral chemical KH203 2 1 refers to the DOC sorbed neutral chemical KH2033 refers to the sediment sorbed neutral chemical 11 33 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Arrhenius Activation Energy kcal mole K The user may specify activation energies for each chemical using constant EHOH Constant numbers are summarized in Table 7 11 If EHOH is omitted or set to 0 hydrolysis rates will not be affected by temperature Reference Temperature C The user may specify the reference temperature at which hydrolysis rates were measured using constant TREFH Constant numbers are summarized in Table 7 11 If a reference temperature is not supplied then a default of 20 C is assumed pH The user may specify time and segment variable pH wlues using parameter 11 PH and time functions 10 and 11 PHNW and PHNS The pH in a water segment will be the product of PH and PHNW the pH in a benthic segment will be the product of PH and PHNS For constant pH the user should enter values via parameter PH Time functions should be omitted For time variable pH the user should enter
213. lankton kinetics Equation 9 25 S r47 onde ey and either the phosphorus cycle Equation 9 26 S7 Dearc Ci ks Ca 0 f pg Cs Equation 9 27 S57 k O85 Cs GnascCs m C or the nitrogen cycle Equation 9 28 Siu 7tD rascCackz 977 C irn f C Equation 9 29 Su tkzuOn Cr G piapcP m Ca kn 0E Ci Equation 9 30 Se tkn OR Ci Gprianc l P w C4 9 33 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 wee where S i is the source sink term for variable i in a segment in mg L day Kinetic rate constants and coefficients are as defined in Table 9 5 Table 9 4 and Table 9 3 Phytoplankton plus either three nitrogen variables or two phosphorus variables are used in simple eutrophication simulations While phytoplankton is simulated internally as mg L carbon initial concentrations and boundary concentrations are input by the user as ug L chlorophyll a EUTRO converts these input concentrations to internal concentrations using a user specified carbon to chlorophyll ratio If the carbon to chlorophyll ratio is not input then a default value of 30 is used Internal concentrations of phytoplankton nitrogen and phytoplankton phosphorus are calculated from user specified nitrogen to carbon and phosphorus to carbon ratios If these ratios are not input then default values of 0 25 and 0 025 are used Simple eutrophication kinetics assumes that death returns phytoplankton nitrogen and phosphorus entirely t
214. lation results files The user should select Add Curve from the x y plot configuration menu when the curve attribute menu appears the user should select the Observed Data radio button Once the radio button has been activated the previously loaded DB file name should appear in the data file dialog box The user should highlight the DB filename with the mouse select the database PCODE and 4 74 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Station_ID to plot Once these items have been selected the user should press the Okay button and the graph will be re drawn with observed data included Note The user has the same control over the observed data s appearance as the simulation results 4 4 9 Printing Results The user has the option of printing the currently active x y plot to any installed Windows printer device this could be a laser printer color printer fax or even email The user has the option of either printing the x y plots in full color or changing them to black and white before printing Depending upon the printer and the users Window s 95 setup the printer may automatically convert the colors to gray scale before printing This may or may not be advantageous if the graphs appear muddy the user should convert the graphs to black and white before printing to a printer saving to a file or copying to a clipboard To change a plot to black and white the user should either select the Black an
215. le type writes the data from the graph in column format each curve will consist of two columns x amp y values The data is separated by commas and can be directly imported into most spreadsheet programs The Paradox file format creates a Paradox compatible database file of all the data in the x y plot This database table that is created can be read directly by Paradox or the Deliberator program a component of WASP Each x y pair from the graph is given it s own record in the database To initiate the export data option the user should press the export data icon on the x y plot toolbar This will bring up a file dialog box that allows the user to define the path and filename to save the exported data To select the file type in which to save the data the user should use the drop down list from the Save As type in the dialog box Chose the appropriate type and give the file a name and press save 4 4 11 Curve Calculations A wide range of calculations can be performed on defined curves on the x y plot The curve calculation screen is entered by pressing the curve calculate button on the x y plot toolbar Curve calculations can only be performed on defined curves within the x y plot window The are several types of curve calculations that can be performed 1 User Defined functions that the user can derive to make calculation 2 Moving Average user specifies the time interval for the moving average and generates a new curve d
216. lids Transport Field The transport field associated with total solids or each solids type must be specified under initial conditions Solid Density g cm The average density of the total sediment or the density of each solids type must be specified This information is used to compute the porosity of benthic segments Porosity is a function of sediment concentration and the density of each solids type Initial Concentrations mg L Concentrations of toxicant and each solids type in each segment must be specified for the time at which the simulation begins If the variable benthic volume option is used the benthic sediment concentrations specified here will remain constant for the entire simulation Dissolved Fraction The dissolved fraction of each solid in each segment should be set to 0 The dissolved fraction of toxicant will be controlled by the partition coefficient and solids concentrations 10 9 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 10 4 5 Transformation Parameters This group of parameters includes spatially variable parameters constants and kinetic time functions for the water quality constituents being simulated None are necessary for sediment transport First Order Degradation There are two options to input first order toxicant degradation Option 1 Total Lumped First Order Decay The use of the simple lumped first order decay rate requires the user to input a decay rate constant f
217. limiting partition coefficient to solids 2 Solids independent limiting partition coefficient to solids 3 TOXI data specifications for sorption are summarized in Table 7 6 For each chemical modeled up to 20 partition coefficients are defined representing the five species of chemical neutral plus four ionic and the four sorbants DOC and three types of solids Normally only a subset of these would be used as defined by those species and solids being modeled Sorption of the neutral chemical to DOC and the solids is defined by the f of the sorbant assumed to be 1 for DOC the octanol water partition coefficient of the chemical Kow the user defined relationship between Kow and Koc and the particle interaction parameter 6 values for each species The input ionic species partition coefficients are used as the limiting partition coefficients in equation 7 40 Constant numbers for the different coefficient options are given in Table 7 7 11 17 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 11 5 6 Option 1 Measured Partition Coefficients For each chemical simulated separate partition coefficients may be entered for sorption of the neutral molecule and up to 4 ionic species onto each of the three possible solids types and DOC The partition coefficient is input in units of L kg not in log units If a partition coefficient is specified it will be used regardless The user is referred to Chapter 6 for detai
218. ls on directly specifying partition coefficients Solids Partition Coefficient L kg The user may directly specify partition coefficients to solids using constant PIXC Constant numbers for sorption of the neutral molecule are given in Table dake DOC Partition Coefficient The user may specify partition coefficients for sorption of ionic species to DOC using constant PIDOC 11 5 7 Option 2 Input of Organic Carbon Partition Coefficient Under this option the user inputs the log base 10 of the organic carbon partition coefficient Koc In addition the user should also input the fraction organic carbon for each of the solids types simulated The fraction organic carbon for dissolved organic carbon is assumed to be 1 0 The fraction organic carbon and dissolved organic carbon concentration are model parameters which may be specified for each model segment If a value for the partition coefficient Kp Option 1 is input then Koc will not be used Organic Carbon Partition Coefficient L kg The user may specify the logio of the organic carbon partition coefficient using constant LKOC Constant numbers are given in Table 7 7 Fraction Organic Carbon The user should specify the segment variable fraction organic carbon for each solids type simulated using parameters FOC L1 FOC L2 and FOC L3 Parameter numbers for solids 1 2 and 3 are 7 8 and 9 respectively Dissolved Organic Carbon mg L The user may specify segment variabl
219. lution option lets the user bypass this procedure allowing negative concentrations This may be desirable for simulating dissolved oxygen deficit in the benthos for example Unchecked prevents negative concentrations checked allows negative concentrations Figure 3 6 Time Step Option The user must specify how time steps will be determined during the simulation 1 user inputs time step history 2 model calculates time step Figure 3 6 Advection Factor dimensionless The advection factor 6 can be specified to modify the finite difference approximation of dc dx used in the advection term by WASP For 6 0 the backward difference approximation is used This is most stable and is recommended for most applications For 6 0 5 the central difference approximation is used This is unstable in WASP and is not recommended A nonzero advection factor is helpful in situations where the network size and time step produce large numerical dispersion A nonzero advection factor reduces the numerical dispersion produced by a particular velocity length and time step combination According to Bella and Grenney 1970 Equation 6 15 E num 5 1 2V L U At Table 6 3 Values of Numerical Dispersion m sec U m sec 0 1 0 2 0 4 0 6 0 8 1 0 At 1000 sec 0 0 95 180 320 420 480 500 0 1 75 140 240 300 320 300 6 14 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 U m sec 0 0 1 0 2 0 4 0 6 0 8 At 1000
220. lyzed by hydrogen ions or proceed by consuming hydroxide ions 8 illustrates the effects of base hydrolysis on carbaryl neutral hydrolysis on chloromethane and acid and base hydrolysis on 2 4 D 11 7 1 Overview of TOXI Hydrolysis Reactions Hydrolysis may be simulated by TOXI using simple decay Alternatively hydrolysis can be simulated using rates that are first order for the neutral chemical and second order for its ionic forms The second order rates are pH and temperature dependant 11 7 2 Option 1 First Order Hydrolysis Under this option the user inputs a first order rate constant for either neutral alkaline or acid hydrolysis The first order rate term constant is then applied to the total chemical concentration see Section 6 3 11 7 3 Option 2 Second Order Hydrolysis Under this option hydrolysis by specific acid catalyzed neutral or base pathways is considered for the various species and phases of each chemical The reactions are first order for the neutral chemical and second order for the acidic or basic forms of the chemical 11 30 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 11 58 TOD i j Equation 11 59 Km7 kulH lfy l Equation 11 60 Kunz 2 kwIOH f i where Kiun net neutral hydrolysis rate constant day Kyun net acid catalyzed hydrolysis rate constant day HH net base catalyzed hydrolysis rate constant day kk specific acid catalyzed a
221. me function TFPO4 The product of the spatially variable FPO4 and time variable TFPO4 gives the segment and time specific benthic flux for PO4 used by EUTRO Flux versus time values can be entered using TFPOA while unitless segment ratios can be entered using FPO4 Values should be entered for water column segments that are in contact with the bottom of the water body Nitrogen to Carbon Ratio mg N mg C The average nitrogen to carbon weight ratio in phytoplankton can be specified using constant NCRB The EUTRO default value for NCRB is 0 25 Phytoplankton Nitrogen Recycle The fraction of dead and respired phytoplankton nitrogen that is recycled to the organic nitrogen pool can be specified using constant FON The default value is 1 The fraction of phytoplankton nitrogen recycled directly to ammonia is 1 FON Nitrogen Mineralization Rate day The mineralization rate constant and temperature coefficient for dissolved organic nitrogen can be specified using constants K71C and KTIT respectively Phytoplankton effects on mineralization can be described using constant KMPHY 9 42 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 the half saturation constant for mineralization dependence on phytoplankton as explained above in the phosphorus mineralization section Nitrification Rate day The nitrification rate constant and temperature coefficient for dissolved ammonia nitrogen can be specified using constants K12
222. ment and particulate chemicals in the water column may settle to bwer water segments and deposit to surficial bed segments Velocities and surface areas in transport fields 3 4 and 5 describe settling deposition and scour rates in WASP6 Particulate transport velocities may vary both in time and in space and are multiplied by cross sectional areas to obtain flow rates for solids and the particulate fractions of chemicals Settling velocities should be set within the range of Stoke s velocities corresponding to the suspended particle size distribution Equation 7 1 8 64g i V Tau P7 P Jd where Ve Stokes velocity for particle with diameter d and density n m day acceleration of gravity 981 cm sec absolute viscosity of water 0 01 poise g cm sec at 20 C density of the solid g cm f density of water 1 0 g cm d particle diameter mm Values of V for a range of particle sizes and densities are provided in Table 7 1 Table 7 1 Stoke s Settling Velocities in m day at 20 c Particle Particle D ensity g cm 3 Diameter mm 1 80 2 00 2 50 2 70 Fine Sand 0 3 300 00 400 00 710 00 800 00 0 05 94 00 120 00 180 00 200 00 Silt 0 05 94 00 120 00 180 00 200 00 0 02 15 00 19 00 28 00 32 00 0 01 3 80 4 70 7 10 8 00 0 005 0 94 1 20 1 80 2 00 0 002 0 15 0 19 0 28 0 32 Clay 0 002 0 15 0 19 0 28 0 32 0 001 0 04 0 05 0 07 0 08 Benthic Exchange The net scour and deposition velocities drive Benthic
223. mestep option is used the user must provide a time series here The last date in the time series determines the simulation end time If the user elects to provide the timestep to the model the user specifies time and time step pairs When WASP is simulating it will plot the information internally and will change the time step based on the time function entered by the user 3 30 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WIN WASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTROJ File Project Pre processor Model Post Processor Help Time Step 1 1 1885 m IE 12004M 2 11 1294 12004M 050 Astart E 2 AY MPPsiShopPro Imege s ASci WIN WASP Bl amp 10254M Figure 3 18 Model Time Step Definition Screen 3 16 Print Interval The print interval is the user specified time function in which simulation results will be written to the simulation result file The WASP model does not have to write information at every time step but can be controlled by the user Depending on the size of the network and time frame being simulated by WASP the simulation result files may be rather large The user has full control over the time frame in which the information is written to the simulation result file This function works like all other time functions in WASP The user must provide the desired time step and simulation time that this in
224. mical i in segment j mgd L C wi Concentration of dissolved chemical i in water in segment j Cwij nj mgd Lw Csij Concentration of sorbed chemical i on sediment type s in segment j mgd L C sj Concentration of sorbed chemical i on sediment type s in segment j mgd kgs Cai Msj C3 Concentration of DO C sorbed chemical i in segment j mgd L C3 Concentration of DOC sorbed chemical i in segment j Cx Bj mgl kgs mg Concentration of sediment type s in segment j mgd L Mg Concentration of sediment type s in segment j mj 10 6 kgy L M s Concentration of sediment type s in water in segment j Ms n kgs Lw Bj Concentration of DOC in segmentj kgp L Bj Concentration of DOC in water in segment j Bj n kgs Lw nj Porosity or volume water per volume segment j Lw L K psij Partition coefficient of chemical i on sediment type s in segment j Lw kgs K ppy Partition coefficient of chemical i on DOC in segment j Lw kgs fpi Fraction of chemical i in segment j in dissolved phase fai Fraction of chemical i in segment j in D O C sorbed phase fej Fraction of chemical i in segment j in solid phase s DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 11 3 lonization Ionization is the dissociation of a chemical into multiple charged species In an aquatic environment some chemicals may occur only in their neutral form while others may react with water molecules to form positively cationic or negatively anioni
225. mperature correction factor Measured ratio of volatilization to reaeration rate Volatilization Option The user should chose the volatilization option using constant XV Specifying a value of O will prevent volatilization from occurring Values of 1 5 will invoke volatilization options 1 5 as outlined in the text above l volatilization rates are input directly 2 volatilization is computed from input reaeration rate constants and O Connor s equation for gas transfer 3 volatilization is computed from input reaeration rate constants and MacKay s equation for gas transfer 4 in flowing systems volatilization is computed using reaeration rates calculated from Covar s method and a gas transfer rate of 100 m day in quiescent systems volatilization is computed from O Connor s equations for liquid and gas transfer 5 in flowing systems volatilization is computed using reaeration rates calculated from Covar s method and a gas transfer rate of 100 m day in quiescent systems volatilization is computed from MacKay s equations for liquid and gas transfer 11 27 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Henry s Law Constant atm m mole The user should specify Henry s Law constant for air water partitioning of the chemical using constant HENRY Atmospheric Concentration ug L The user should specify the mean atmospheric concentration of chemical using constant ATMOS If this concentration is 0 then v
226. mpute average light intensity for the month indicated by TO 3 compute monthly light intensity as a step function Optical Path The user may specify the ratio of the optical path to the vertical depth using constant 7 DFACG A default value of 1 17 is assumed 11 40 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Cloud Cover tenths The user should specify the mean monthly or annual average cloud cover using constant CLOUDG Monthly values can be entered using constant numbers 11 22 the annual average can be entered using number 23 Air Type The user should specify the mean air mass type using constant AIRTYG Values of 1 2 3 or 4 will select rural urban maritime or tropospheric respectively Monthly values can be entered using constant numbers 24 35 the annual average can be entered using number 36 Relative Humidity percent The user should specify the mean monthly daylight relative humidity using constant RHUMG Monthly values can be entered using constant numbers 37 48 the annual average can be entered using number 49 Atmospheric Turbidity km The user should specify the mean atmospheric turbidity in equivalent aerosol layer thickness km using constant ATURBG Monthly values can be entered using constant numbers 50 61 the annual average can be entered using number 62 Ozone Content cm NTP The user should specify the mean ozone content cm NTP using constant OZONEG Monthly values c
227. n e fr Cat kes OS 2 7 Ca Gri ave C s o Segen C Eust Death Miezalsaton Gn wh Figure 9 4 Phosphorus cycle equations Table 9 4 Phosphorus reaction terms Description Notation Value Units Phytoplankton biomass as carbon Pc mgC L Specific phytoplankton growth rate G pij eq 5 2 day Phytoplankton loss rate D pij eq 5 14 day Phosphorus to carbon ratio apc 0 025 mgP mgC Dissolved organic phosphorus mineralization at 20 C ks3 0 22 day Temperature coefficient s 1 08 none Half saturation constant for phytoplankton limitation of Kmpc 1 0 mgC L phosphorus recycle Fraction of dead and respired phytoplankton recycled to fop 0 5 none the organic phosphorus pool recycled to the 1 fop 0 5 none phosphate phosphorus pool Fraction dissolved inorganic phosphorus in the water fp3 0 85 none column 0 70 Fraction dissolved organic phosphorus fos none Organic matter settling velocity Vs3 m day Inorganic sediment settling velocity Vs m day 9 17 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 9 2 1 Phytoplankton Growth As phytoplankton grow dissolved inorganic phosphorus is taken up stored and incorporated into biomass For every mg of phytoplankton carbon produced apc mg of inorganic phosphorus is taken up 9 2 2 Phytoplankton Death As phytoplankton respire and die biomass is recycled to nonliving organic and inorganic matter For every mg of phytoplankton carbon consumed or lost c mg of ph
228. n 6 6 acezl Equation 6 7 b d f l WASP6 only requires specification of the relationships for velocity Equation 6 1 and depth Equation 6 2 the coefficients for Equation 6 3 are implicitly specified by Equation 6 6 and Equation 6 7 These options can be put into perspective by noting that for a given specific channel cross section the coefficients a c e and exponents b d f can be derived from Manning s equation For example if a channel of rectangular cross section is assumed then width B is not a function of stream flow Q the exponent f is zero 0 00 and the coefficient e is the width of the rectangular channel B By noting that hydraulic radius R is approximately equal to depth D br wide streams and that A D B the discharge coefficients for rectangular cross sections can be shown to be 0 4 for velocity and 0 6 for width Leopold et al 1964 have noted that stream channels in humid regions tend towards a rectangular cross section because cohesive soils promote steep side slopes whereas noncohesive soils encourage shallow sloped almost undefined banks Table 6 2 Comparison of Hydraulic Exponents Exponent Exponent for For d Exponent for f Channel Cross Section b Velocity Depth Width Rectangular 040 00 00 6 5 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Exponent Exponent for Exponent for f Channel Cross Section b Velocity Width Average of 158 U
229. n Anoxic Marine Sediments In The Sea Vol 5 ed E D Goldberg J Wiley and Sons New York Bowie G L W B Mills D B Porcella C L Campbell J R Pagenkopf G L Rupp K M Johnson P W H Chan S A Gherini and C E Chamberlin 1985 Rates Constants and Kinetics Formulations in Surface Water Quality Modeling Second Edition U S Environmental Protection Agency Athens GA EPA 600 3 85 040 Brown L C and T O Barnwell 1987 The Enhanced Stream Water Quality Models QUAL2E and QUAL2FE UNCAS Documentation and User Manual U S Environmental Protection Agency Athens GA EPA 600 3 87 007 Burns L A D M Cline and R R Lassiter 1982 Exposure Analysis Modeling System EXAMS User Manual and System Documentation U S Environmental Protection Agency Athens GA EPA 600 3 82 023 12 1 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Burns L A and D M Cline 1985 Exposure Analysis Modeling System Reference Manual for EXAMS II U S Environmental Protection Agency Athens GA EPA 600 3 85 038 Connolly J P and R Winfield 1984 A Users Guide for WASTOX a Framework for Modeling the Fate of Toxic Chemicals in Aquatic Environments Part 1 Exposure Concentration U S Environmental Protection Agency Gulf Breeze FL EPA 600 3 84 077 Connolly J P and R V Thomann 1985 WASTOX A Framework for Modeling the Fate of Toxic Chemicals in Aquatic Environments Part 2 Food Chain U S Environmenta
230. n Rate day The nitrification rate constant and temperature coefficient for dissolved ammonia nitrogen can be specified using constants K12C and K12T respectively Nitrogen Half Saturation Constant mg N L The nitrogen half saturation constant for phytoplankton growth can be specified using constant KMNGI When inorganic nitrogen concentrations are at this level the phytoplankton growth rate is reduced by half This parameter also affects ammonia preference Pypus as outlined in Figures 5 5 and 5 6 When KMNGI 0 Pnn 1 0 When KMNGI becomes very large Pyy3 approaches a value of Cj C C2 9 7 Intermediate Eutrophication Kinetics Intermediate eutrophication kinetics simulates the growth and death of phytoplankton interacting with the nitrogen and phosphorus cycles and the dissolved oxygen balance Growth can be limited by the availability of inorganic nitrogen inorganic phosphorus and light Intermediate eutrophication kinetics adds CBOD and DO equations as well as certain nonlinear terms and functions to the simple eutrophication kinetics described above The oxygen balance equations and kinetic parameters are summarized in Figure 8 2 and Table 8 1 The phosphorus cycle equations and kinetic parameters are summarized in Figure 9 4 and Table 9 4 The nitrogen cycle equations and parameters are summarized in Figure 9 5 and Table 9 5 Phytoplankton equations are presented throughout Section 9 1 4 with parameters summarized in Table 9
231. n participate in DO balance simulations with abbreviations used in this text are listed in Table 8 3 Table 8 3 Summary of EUTRO Variables used in DO Balance Variable Notation Concentration Units 1 Ammonia Nitrogen NH3 Ci mg N L 2 Nitrate Nitrogen NO3 C2 mg N L 4 Phytoplankton Carbon PHYT C4 mgC L 5 Carbonaceous BO D CBOD C5 mgO7 L 6 Dissolved Oxygen DO Ce mgO2 L 6 Organic Nitrogen ON C7 mg N L 8 3 1 Streeter Phelps The simplest dissolved oxygen balance solves the Streeter Phelps BOD DO equations in a slightly modified form 8 14 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 8 15 Sa ka Or c 1 3 965 Equation 8 16 SODr Sis tk057 C Cs k401 7 C 5 D nin where Sx is the source sink term for variable i in a segment in mg L day Kinetic rate constants and coefficients are as defined in Table 4 1 except that G is interpreted as total not just carbonaceous biochemical oxygen demand BOD These equations are usually applied in well defined low flow design conditions 8 3 2 Environment Parameters These parameters define the basic model identity including the segmentation and control the simulation Systems Select simulate for CBOD and DO and bypass for the other six systems For this implementation the CBOD system is used to represent total ultimate BOD Figure 3 7 Segments Water column segments should be defined in the standard fashion If BOD settling
232. nd Physics CRC Press Boca Raton FL Wetzel R G 1975 Limnology W B Saunders Co Philadelphia 743 pp Whitman R G 1923 lt A Preliminary Experimental Confirmation of the Two Film Theory of Gas Absorption Chem Metallurg Eng 29 146 148 Wischmeier W H and D D Smith 1978 Predicting Rainfall Erosion Losses A Guide to Conservation Planning Agriculture Handbook No 537 U S Dept of Agriculture Washington DC Wolfe N L 1980 Determining the Role of Hydrolysis in the Fate of Organics in Natural Waters pp 163 178 in R Haque Ed Dynamics Exposure and Hazard Assessment of Toxic Substances Ann Arbor Science Publisheres Ann Arbor Zepp R G and D M Cline 1977 Rates of Direct Photolysis in Aquatic Environment Environ Sci Technol 11 359 366 12 6
233. nd base rate constants for ionic specie iin phase j respectively molar day kj neutral rate constant for ionic specie i in phase j day f fraction of chemical as ionic specie i in phase j The rates are also affected by temperature TOXI adjusts the rates using the temperature based Arrhenius function Equation 11 61 k T 2 k T amp exp 1000 E u T k Ta V RT T n where Tx water temperature K Tr reference temperature for which reaction rate is reported K En Arrhenius activation energy for hydrolysis reaction kcal mole eK R B 1 99 cal mole K 1000 cal kcal Implementation 11 31 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Description Notation Range Units Negative log of hydrogen ion activity H pH 5 9 Acid hydrolysis rate constant for specie i kuaj 0 107 phase j Neutral hydrolysis rate constant for specie i kuwj 0 102 day phase j Base hydrolysis rate constant for specie i kusi 0 107 phase j Water temperature T 4 30 C Activation energy for hydrolysis reaction for Eani 15 25 specie i TOXI hydrolysis data specifications are summarized in Table 7 10 In addition the simple first order rates may be specified as described under Option 1 and the section on simple TOXI reactions If no hydrolysis data are input then the effect of hydrolysis will not be included in simulations Option 1 Under this option the user inputs one or more of the following an a
234. nd set of loads is read by WASP6 from a nonpoint source loading file created by an appropriate loading model Both kinds of loads in kg day are added to the designated segments at the following rates Equation 6 14 Vi Six 10009 p t where Si loading rate response of chemical k in segment i g m day L O loading rate of chemical k into segment i kg day Point source loads are input as a series of loading versus time values During a simulation WASP6 interpolates between these points to provide time variable loadings The WASP6 calculational time step should be set by the user to a value that is divisible into the difference in time entries in the point source loading functions If evenly divisible time steps cannot be specified the user should specify maximum time steps at 6 10 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 least 5 times smaller than the point source time entries If the user is specifying daily load variations for example the maximum time step should be 0 2 days The user should understand that mass entered as loads is not directly accompanied with inflow No significant errors are introduced if the inflow associated with a loading is small compared with the water body flow If a loading is associated with significant inflow then the user should generally enter the associated flows separately under water column advection and treat the loading as a model boundary by specifying t
235. ne of three formulas Owens Churchill or O Connor Dobbins respectively Equation 8 2 k 20 C 5 349 y p75 8 4 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 8 3 k qj 20 C 5 049 y py 157 or k4 2000 5 3 93 59 pF where ka flow induced reaeration rate coefficient at 20 C day Vj average water velocity in segment j m sec D average segment depth m The Owens formula is automatically selected for segments with depth less than 2 feet For segments deeper than 2 feet the O Connor Dobbins or Churchill formula is selected based on a consideration of depth and velocity Deeper slowly moving rivers require O Connor Dobbins moderately shallow faster moving streams require Churchill Segment temperatures are used to adjust the flow induced k j 20 C by the standard formula Equation 8 4 k4i D k 20 C 9 where T water temperature C kg T reaeration rate coefficient at ambient segment temperature day a temperature coefficient unitless Wind induced reaeration is determined by O Connor 1983 This method calculates reaeration as a function of wind speed air and water temperature and depth using one of three formulas Equation 8 5 2 3 1 2 86400 Dow p K ta ie 100 ew kwj 100 D Vw A T Ca 8 5 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 8 6 86400 7s TERMI e 100W TERM2 410
236. ng through each time interval 4 3 10 Palette The user has the ability to modify the color palette that is used to shade the plot The most common modification to the color palette would be to invert the currently loaded palette Clicking on the Invert radio button will cause the color palette to be inverted i e the colors for the lower values will become the colors for the higher values The user also has the ability to select a different color scheme by selecting a new palette To select a new palette the user should press the browse button and select a palette 4 3 11 Animation The most common use for the spatial analysis grid is to animate the model predictions When the forward backward buttons on the toolbar are pressed the spatial analysis grid is updated with the next time or variable depending upon the varying parameter By continually pressing the forward button the user can create a movie of the model predicted results Alternatively the user may press the movie icon The speed of the animation is controlled by the options under the spatial plot parameters 4 3 12 Plot Mode Three modes are provided by which data can be displayed in the spatial grid analysis window Shaded This mode displays the simulation results by shading the model computational element based upon the predicted concentration A color legend is displayed on the right hand side of the spatial analysis window and the computational elements are shad
237. nionic or cationic using equation 7 66 and the values listed in Tables 7 12 and 7 13 If the wavelength of maximum absorption is outside of the relevant spectral range 280 825 nm then TOXI assumes a wavelength of 300 nm 11 38 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 After adjusting the reference sunlight absorption rate to ambient conditions the first order photolysis rate is computed from these and reaction quantum yields following equation 7 63 Photolysis option 2 is often implemented using reference first order photolysis rate constants rather than reference sunlight absorption rates If reference first order rate constants are input for kari then equation 7 67 calculates kj as first order rate constants day adjusted to ambient light conditions The overall first order photolysis rate constant is then calculated following equation 7 63 where quantum yields are set to 1 0 Description Notation Range Units Observed rate constant for a chemical at reference Kpr 0 10 day light intensity In Observed sunlight absorption rate for a chemical at kar E mole day reference light intensity IR Reference light intensity causing photolysis rate Kpror Ir 10 7 2x10 6 E cm sec absorption rate kar Ratio of surface light intensity to reference light Io 0 10 intensity Io In Light extinction coefficient in water column Ke 0 1 5 mi Chlorophyll a concentration CHL 103 101 mg L Dissolved organic carbon DOC 0
238. nnolly and Winfield 1984 Ambrose R B et al 1988 This model helps users interpret and predict water quality responses to natural phenomena and man made pollution for various pollution management decisions WASP6 is a dynamic compartment modeling program for aquatic systems including both the water column and the underlying benthos The time varying processes of advection dispersion point and diffuse mass loading and boundary exchange are represented in the basic program Water quality processes are represented in special kinetic subroutines that are either chosen from a library or written by the user WASP is structured to permit easy substitution of kinetic subroutines into the overall package to form problem specific models WASP6 comes with two such models TOXI for toxicants and EUTRO for conventional water quality Earlier versions of WASP have been used to examine eutrophication of Tampa Bay phosphorus loading to Lake Okeechobee eutrophication of the Neuse River and estuary eutrophication and PCB pollution of the Great Lakes Thomann 1975 Thomann et al 1976 Thomann et al 1979 Di Toro and Connolly 1980 eutrophication of the Potomac Estuary Thomann and Fitzpatrick 1982 kepone pollution of the James River Estuary O Connor et al 1983 volatile organic pollution of the Delaware Estuary Ambrose 1987 and heavy metal pollution of the Deep River North Carolina JRB 1984 In addition to these numerous applications are l
239. nt 1 0 organic carbon fraction of DOC Option 3 Computation of the Organic Carbon Partition Coefficient Correlation of Koc with the water solubility of the chemical or the octonal water partition coefficient of the chemical has yielded successful predictive tools for incorporating the hydrophobicity of the chemical in an estimate of its partitioning If no log Koc values are available one is generated internally using the following correlation with the octanol water partition coefficient Kow Lw Loct Equation 11 38 log K oc Ao ai log K ow where a and a are typically considered to be log 0 6 and 1 0 respectively Once the value of Koc is determined the computation of the partition coefficient proceeds as in Option 2 11 5 5 Option 4 Computation of Solids Dependant Partitioning The value of the partition coefficient is dependent on numerous factors in addition to the fraction organic carbon of the sorbing particles Of these perhaps the most potentially significant and the most controversial is the effect of particle concentration which was first presented by O Connor and Connolly 1980 Based on empirical evidence O Connor and Connolly concluded that the partition coefficient was inversely related to the solids concentration Much research has been conducted to prove or disprove this finding At present the issue remains contentious A particle interaction model has been proposed Di Toro 1985 which describes the effects
240. ntrations that may result from unsteady loads or spills Natural or artificial tracers such as dye salinity or even heat are often used to calibrate dispersion coefficients for a model network 6 7 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 In WASP6 water column dispersion is input via transport field one in Figure 3 13 The user may define several groups of exchanges For each group the user must supply a time function giving dispersion coefficient values in m sec as they vary in time For each exchange in the group the user must supply an interfacial area a characteristic mixing length and the adjoining segments between which the exchange takes place The characteristic mixing length is typically the distance between the segment midpoints The interfacial area is the area normal to the characteristic mixing length shared by the exchanging segments cross sectional area for horizontal exchanges or surface area for vertical exchanges The actual dispersive exchange between segments i and j at time t is given by Equation 6 9 OMix_ Ej t A c ij wo E Ot L5 C ix Ci where M mass of chemical k in segment i g Ci C concentration of chemical k in segment i and j mg L g m E t dispersion coefficient time function for exchange ij m day A interfacial area shared by segments i and j m Lj characteristic mixing length between segments i and j m 6 2 5 Pore Water Diffus
241. nwasp Example T ampa WIF Tampa Input Data Set EUTRO File Project Pre processor Model Post Processor Help Segments Segments Parameters Initial Concentrations Fraction Dissolved Description Depth Multiplier asp Segment 1 7000 Wasp Segment 2 7000 wasp Segment 2 6000 wasp Segment 2 6000 wasp Segment 3 5000 wasp Segment 3 0000 wasp Segment 4 5000 wasp Segment 4 2000 m Segment 4 4000 Wasp Segment 3 7000 Mstart E 2 A B Paint Shop Pio mages tE ASci WIN WASP EE 10284M Figure 3 8 Segment Definitions Inserting Deleting Segments Before the user can define a segment the user needs to insert a segment by clicking on the insert button This will cause a segment to be inserted at the active row in the table 3 17 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 If this is the first segment to be inserted it will initiate the table and insert a row at the top To delete a segment highlight the row in which you want to delete and click on the delete button Segment Naming Convention WASP6 automatically names the segments by numbers 1 through the number of segments WASP6 also allows the user to give an alphanumeric name to individual segments This alphanumeric name is there for the convenience of the user and will appear on the other screens Dispersion Flow as well as in the post processor so that the user do
242. o the organic nitrogen and organic phosphorus pools Mineralization is a simple first order function that is unaffected by phytoplankton levels and nitrification is a simple first order function unaffected by dissolved oxygen Denitrification is not simulated Light limitation is described by the Di Toro formulation Equation 9 4 and the user must calibrate the saturating light intensity I The particulate fractions of ON and OP are associated with transport field 3 organic matter settling Particulate PHYT is associated with transport field 4 The particulate fraction of PO4 is associated with transport field 5 inorganic settling 9 6 1 Environment Parameters These parameters define the basic model identity including the segmentation and control the simulation Systems Select simulate for PHYT and either ON NH3 and NO3 or OP and PO4 Select constant for the nonsimulated nutrients and bypass for CBOD and DO During calibration the user may select constant or bypass for any selected variables Segments Water column segments should be defined in the standard fashion If settling is to be simulated i e for ON OP PHYT or PO4 the user should add a single benthic segment underlying all water column segments This benthic segment will merely act as a convenient sink for settling organic matter Model calculations within this benthic segment should be ignored 9 6 2 Transport Parameters This group of parameters
243. odified by a temperature function Ratio of Volatilization to Reaeration The user may specify an experimentally measured ratio of volatilization to reaeration using constant KVOG If this constant is not given the ratio will be calculated from molecular weight Molecular Weight g mole The user may specify the molecular weight using constant MOLWT This constant is used to calculate the ratio of volatilization to reaeration if an experimentally measured value is not provided It is also used in the calculation of diffusivities Wind Speed m sec The user may specify the segment and time variable wind speed using parameter 4 WVEL and time function 9 WINDN The product of spatially variable WVEL 11 28 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 and time variable WINDN gives the segment and time specific reaeration rate constants used by TOXI Wind speed should be measured at 10 m height above the water surface Air Temperature C The user may specify time variable air temperature using constant AIRTMP and time function 13 AIRTMPN The ambient air temperature is calculated as the product of AIRTMP and AIRTMPN For a constant air temperature AIRTMPN can be omitted For variable air temperatures the user should set AIRTMP to 1 0 and input a series of air temperature versus time values via AIRTMPN 11 6 9 Volatilization Option 3 In this option volatilization rates are calculated from user input reaer
244. of the simulation switches input in Record 4 This is for user convenience only Figure 3 6 Number of Segments The user must define the segments The preprocessor automatically counts the number of segments Figure 3 8 6 13 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Number of Systems The user must specify the number of model systems state variables in the simulation In the preprocessor select simulate for Chemical 1 and bypass for Chemicals 2 and 3 and Solids 1 3 Figure 3 7 Restart Option The user must specify the restart option which controls the use of the simulation restart file This restart file stores the final conditions from a simulation and can be used to input initial conditions in a sequential simulation 1 neither read from nor write to the restart file 2 write final simulation results to restart file 3 read initial conditions from restart file created by earlier simulation and write final simulation results to new restart file Figure 3 6 Mass Balance Analysis The user should specify the system number for which a global mass balance analysis will be performed A value of O will result in no mass balance table being generated Figure 3 7 Negative Solution Option Normally concentrations are not allowed to become negative If a predicted concentration at t At is negative WASP maintains its positive value by instead halving the concentration at time t The negative so
245. ogen and phosphorus flux functions should be omitted and the following should be modified or added Segments Water column segments should be defined in the standard fashion In addition the user should add a benthic segment underlying each water column segment or stack of water column segments These benthic segments will receive settling organic and inorganic matter from the water column above and can return material to the water column via resuspension or by pore water diffusion Phytoplankton Decomposition day The user may specify the rate constant and temperature coefficient for phytoplankton decomposition in benthic segments using constants KPZDC and KPZDT Carbonaceous BOD Decomposition day The user may specify the rate constant and temperature coefficient for CBOD decomposition in benthic segments using constants KDSC and KDST Organic Nitrogen Decomposition day The user may specify the rate constant and temperature coefficient for organic nitrogen decomposition in benthic segments using constants KONDC and KONDT Organic Phosphorus Decomposition day The user may specify the rate constant and temperature coefficient for organic phosphorus decomposition in benthic segments using constants KOPDC and KOPDT 9 44 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 10 Simple Toxicants Some organic and inorganic chemicals can cause toxicity to aquatic organisms or bioconcentrate through the
246. olatilization will always cause a loss of chemical from the water body 11 6 7 Volatilization Option 1 In this option variable volatilization rate constants can be input directly Volatilization Rates m day When XV is set to 1 the user may then input segment and time variable volatilization rates using parameter 5 REAR and time function 12 REARN The product of spatially variable REAR and time variable REARN gives the segment and time specific volatilization rate constants used by TOXI These volatilization values are not modified by a temperature function 11 6 8 Volatilization Option 2 In this option volatilization rates are calculated from user input reaeration rate constants and O Connors method for gas transfer Input data required for option 2 are listed below For flowing systems wind speed and air temperature are not used and may be omitted Water Body Type The user should specify the water body type using constant WTYPE A value of O indicates a flowing water body such as a stream river or estuary A value of 1 indicates a quiescent water body such as a pond reservoir or lake Reaeration Rates m day When XV is set to 2 the user may then input segment and time variable reaeration rates using parameter 5 REAR and time function 12 REARN The product of spatially variable REAR and time variable REARN gives the segment and time specific reaeration rate constants used by TOXI These reaeration values are not m
247. olid type 1 which represents organic matter Time and segment variable organic matter settling velocities v3 can be input by the user using transport field 3 Segment variable organic phosphorus dissolved fractions psj are input with initial conditions Particulate inorganic phosphorus is equated to solid type 3 which represents inorganic sediment Time and segment variable inorganic phosphorus settling velocities vss can be input by the user using transport field 5 Segment variable inorganic phosphorus dissolved fractions 3 are input with initial conditions 9 3 The Nitrogen Cycle Four nitrogen variables are modeled phytoplankton nitrogen organic nitrogen ammonia and nitrate A summary is illustrated in Figure 9 5 Table 9 5 summarizes the terms used in the nitrogen system kinetics 9 21 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Phytoplankton Nitrogen O C ane V4 aia ee C4 Done C a4 Gne C 4 a Growth Death Setting Organic Nitrogen Kure Ce D Death Miezalsatbn Setting ee Dran fn Ci kn Of E Ci ae e Ammonia Nitrogen Be Daan l fn Cs kn Xr C1 Gn a Pus Ca ki 779 2 C1 x Kemer C4 Kur Cs Death Mire rabiston Growth Nitrification Nitrate Nitrogen 7 gom Ee Ci Ga dw 1 Paes Cs kan 770 mo Ca e Kwr C s Kos C s Nitrification Gaowfh Denitrification Ca E Pant op renters o lrosenitses Figure 9 5 Nitrogen cylce equations Table 9 5 Nitrogen
248. om by dragging a box to the end time The zoomed area will be painted EN Post processor Tampa Bay BEE E File Edit View XY Plot Window Help 18 x az DO mg l A 4 A A LUAM MI IN TwIVIVAF e 3 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 Year 1989 4 4 gt 98 amp ex S 2 E ea sd emn CAPS NUM OVA Astan e 7 9 89 Paint Shop Pro Image13 F Post processor tTa Bl amp 226PM Figure 4 15 Zooming the x Axis Upon releasing the left mouse button after the user has defined the area to mom the x y plot will be redrawn for the given time period selected by the user Figure 4 16 illustrates a zoomed x axis from the example given above 4 68 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 E Post processor Tampa Bay BEE faa File Edt View XY Plot Window Help 218 x ey DO mg l 3 Dec 87 Feb 88 Apr 88 Jun 88 Aug 88 Oct 88 Dec 88 Feb 89 Year 1988 4 4 gt amp amp 5x Sy ea BJ en s een CAPS NUM OVR Asun E SAY X Pant Shop Pro Image14_ E Post processor ITa Bl amp 22m Figure 4 16 Zoomed x Axis Note The user can zoom the axis in steps i e zoom look atthe graph and then zoom the zoomed graph some more The user also has two other functions available from the toolbar un zoom x y plot or return to previous zoomed level Zooming the Y The y axes may also be zoomed The user has
249. on model or by output from a spreadsheet As formatted ASCII files they may be edited using standard text editors Hydrodynamic files are denoted by HYD where the user specifies a 1 to 8 character name for Nonpoint source loading files are denoted by NPS The contents and format for these files are specified on page 3 13 6 19 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 7 Sediment Transport Sediment transport is potentially a very important process in aquatic systems Excess sediment can affect water quality directly Water clarity and benthic habitats can be degraded Sediment transport also influences chemical transport and fate Many chemicals sorb strongly to sediment and thus undergo settling scour and sedimentation Sorption also affects a chemical s transfer and transformation rates Volatilization and base catalyzed hydrolysis for example are slowed by sorption Both sediment transport rates and concentrations must be estimated in most toxic chemical studies In general the stream transport capacity for suspended sediment is in excess of its actual load and the problem is one of estimating sediment source loading namely watershed erosion In areas of backwater behind dams or in sluggish reaches the stream transport capacity may drop enough to allow net deposition Strongly sorbed pollutants may build up significantly Because sediment transport can be complex site specific calibration of the set
250. on of Toxic Chemicals in Water and Soil In Dynamics Exposure and Hazard Assessment of Toxic Chemicals R Haque editor Ann Arbor Science Ann Arbor MI Ambrose R B 1987 Modeling Volatile Organics in the Delaware Estuary American Society of Civil Engineers Journal of Environmental Engineering V 113 No 4 pp 703 721 Ambrose R B et al 1988 WASP4 A Hydrodynamic and Water Quality Model Model Theory User s Manual and Programmer s Guide U S Environmental Protection Agency Athens GA EPA 600 3 87 039 APHA American Public Health Association 1985 Standard Methods for the Examination of Water and Wastewater 15th Edition APHA Washington DC Bannister T T 1974a Production Equations in Terms of Chlorophyll Concentration Quantum Yield and Upper Limit to Production Limnol Oceanogr 19 1 12 Bannister T T 1974b A General Theory of Steady State Phytoplankton Growth in a Nutrient Saturated Mixed Layer Limnol Oceanogr 19 13 30 Barber M C L A Suarez and R R Lassiter 1991 Modelling Bioaccumulation of Organic Pollutants in Fish with an Application to PCBs in Lake Ontario Salmonids Canadian J Fisheries and Aquatic Sciences Vol 48 pp 318 337 Bella D A and W J Grenney 1970 Finite Difference Convection Errors Journal of the Sanitary Engineering Division ASCE Vol 96 No SA6 pp 1361 1375 Berner R A 1974 Kinetic Models for the Early Digenesis of Nitrogen Sulfur Phosphorus and Silicon i
251. onmental property driving this reaction kj second order rate constant for chemical as specie in phase j in E day f fraction of chemical as specie i in phase j The reaction coefficients may be specified as constants with activation energy constants left as 0 If the user wants TOXI to determine rates based on the temperature based Arrhenius function then non zero activation energies specified as constants will invoke the following calculation for each rate constant k 11 49 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 11 74 k T x k T x expll000 E T x T RM RT KTR where Hz Arrhenius activation energy for extra reaction kcal mole K Activation energies may be specified for each ionic specie simulated If no activation energies are given then rate constants will not be adjusted to ambient water temperatures An example of a kinetic process that may be modeled as this extra reaction is reduction If reduction is modeled E may be interpreted as the concentration of environmental reducing agents RH so that Equation 11 75 C RH P and E x Concentration of RH moles L k second order rate constant L mole day P reduced product The identity of the reducing agent and the second order rate constant must be identified and quantified by laboratory kinetics studies If both the environmental oxidizing and reducing agents are in excess then two chemicals may be simulate
252. or a lower bed layer volumes are held constant along with density To maintain mass balance the average sedimentation velocity is effectively Equation 7 10 Ws WsSi Sx For locations where sediment scour exceeds deposition WASP responds as in Figure 7 2 As sediment and sorbed chemical erode from the bed the top bed segment decreases in volume depth chemical mass and sediment mass Its density remains constant When the sediment mass in the top bed layer equals zero then segment renumbering is triggered All the properties of the remaining bed segments including chemical concentration remain unaffected by renumbering The new top bed segment for example has the same depth volume and sediment and chemical concentration as the old second bed segment A new bottom bed segment is created with the same physical properties as the other bed segments Its chemical concentration however is zero Renumbering and creation of a new bottom segment completes the WASP6 erosion cycle or time step As a consequence of the way the variable bed volume option treats sedimentation certain constraints are imposed on the bed segment properties defined in the input data set The density or sediment concentration d a top bed segment must be less than or equal to the density of the lower bed segments within a vertical stack Since the compaction routine implicitly handles sedimentation no sedimentation velocities to lower beds may be specified in the
253. or the chemical for each model segment If a simple lumped first order rate is specified for a particular chemical the chemical will decay at that rate regardless of other input For example if both a lumped decay rate and either a simple first order or second order transformation rate are specified the simple first or second order rates will only be used if the lumped rate is zero Option 2 Individual First Order Transformation REACTION KV day Volatilization THV day 141 74 Water Column Biodegradation 142 1342 Benthic Biodegradation 144 Alkaline Hydrolysis KHN day THHN day KHH day THHR day The use of the simple first order transformation rate requires the user to input a global rate constant day or half life day for each particular processes simulated If a simple first order 10 10 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 transformation rate is specified it will take priority over other input for that particular processes For example if both a first order and a second order transformation rate constant is specified the second order rate will only be used if the first order rate constant is zero First order transformation rate constant numbers are given in Table 6 3 Partition Coefficients TOXI allows the input of either a single constant partition coefficient or a set of spatially variable partition coefficients Option 1 Constant Partition Coefficient Ca et eo
254. osphorus is released A fraction fop is organic while 1 fop is in the inorganic form and readily available for uptake by other viable algal cells In work on the Great Lakes fop was assigned at 50 Di Toro and Matystik 1980 9 2 3 Mineralization Nonliving organic phosphorus must undergo mineralization or bacterial decomposition into inorganic phosphorus before utilization by phytoplankton In their work on Lake Huron and Saginaw Bay Di Toro and Matystik 1980 proposed a nutrient recycle formulation that was a function of the localized phytoplankton population This proposal was based on both an analysis of available field data and the work of others Hendry 1977 Lowe 1976 Henrici 1938 Menon 1972 and Rao 1976 that indicated bacterial biomass increased as phytoplankton biomass increased EUTRO uses a saturating recycle mechanism a compromise between conventional first order kinetics and a second order recycle mechanism wherein the recycle rate is directly proportional to the phytoplankton biomass present as had been indicated in pure culture bacteria seeded laboratory studies Jewell and McCarty 1971 Saturating recycle permits second order dependency at low phytoplankton concentrations when P lt lt Kap where Kype is the half saturation constant for recycle and permits first order recycle when the phytoplankton greatly exceed the half saturation constant Basically this mechanism slows the recycle rate if the phytopl
255. oss the WASP6 segment boundaries must be averaged All of the averaged flows across a boundary must then be summed and written to the hydrodynamic file Again it is important to note the presence of hydrodynamic elements outside the WASP6 network generating boundary flows The preprocessor will determine the boundary segments 6 3 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 from reading the hydrodynamic linkage file The user will then be able to enter concentrations associated with each of these boundaries Figure 3 15 To implement the hydrodynamic linkage the user must specify Hydrodynamic Linkage and select a previously created hydrodynamic linkage file Following the choice of a proper file the hydrodynamic file will reset the simulation time step The time steps read in Figure 3 18 will be ignored but must still be entered as this is where the user specifies the ending time for the simulation Similarly water column segment volumes will be read from the hydrodynamic file The user must nevertheless enter volumes for each segment in the usual location During the simulation flows and volumes are read every time step 6 2 2 Hydraulic Geometry A good description of segment geometry as a function of flow conditions can be important in properly using WASP6 to simulate rivers For flow option 3 velocity and depth are computed within the hydrodynamic model and are read by WASP6 For flow options 1 and 2 a set o
256. ounted Figure 3 10 Dissolved Fractions The initial fraction of chemical dissolved in the water portion of a segment is input as a fraction of total chemical concentration The dissolved fraction is important in determining the amount of chemical transported by pore water flow and dispersion and by solids transport Dissolved fractions may be computed from sorption kinetics in the transformation subroutines Figure 3 11 Solid Densities g cm The density of each type of solid is needed to compute the porosity of bed segments Porosity will be a function of sediment concentration and the density of each solid type Figure 3 7 6 18 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Maximum Concentrations mg L Maximum concentrations must be specified for each water quality constituent The simulation is automatically aborted if a calculated concentration falls outside these limits This usually indicates computational instability and the time step must usually be reduced Figure 3 7 6 4 4 Transformation Parameters This group of parameters includes spatially variable parameters constants and kinetic time functions for the water quality constituents being simulated None are necessary for dissolved conservative chemicals 6 4 5 External Input Files At the user s option two external input files may be called upon and used by WASP6 during a simulation These formatted files may be created by a simulati
257. ow Help yz 2 xi XY Parameters Curves General Domain Primary Range Secondary Range Curve Attributes Data Representation Miscellaneous Predicted data C PROGRAM FILESSASCI DO Maximum Segment 7 DO Saturation bd Segment 8 zi ccr ERES CAPS NUM OVR start S A X Pant shop Pro Image5 Ez Post processor Bl amp 222Pm Figure 4 14 Input File Selection 4 64 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Data Source Data are obtained from several sources and are available for plotting within the x y plot window For the data to be available for a given plot window it must either be read into memory read from disk simulation result files or observed database or created from a previous calculation The radio buttons located within the Data Source dialog window will be available for selection if the particular type is available for plotting The model simulation results file and the observed data databases are loaded using the Open File dialog from the main menu The calculated data sources are created from within the x y plot window A calculated data source created in one x y plot window is available to other x y plot windows as well Predicted The predicted data type is assigned to the files that contain model simulation results Observed The observed type is assigned to the observed data database The observed data database must have a
258. ow concentrations The second transport field specifies the movement of pore water in the sediment bed Dissolved water quality constituents are carried through the bed by pore water flow and are exchanged between the bed and the water column by pore water diffusion The third fourth and fifth transport fields specify the transport of particulate pollutants by the settling resuspension and sedimentation of solids Water quality constituents sorbed onto solid particles are transported between the water column and the sediment bed The user can define the three solids fields as size fractions such as sand silt and clay or as inorganic phytoplankton and organic solids The sixth transport field represents evaporation or precipitation from or to surface water segments 5 7 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Most transport data such as flows or settling velocities must be specified by the user in a WASP input dataset For water column flow however the user may link WASP with a hydrodynamics model If this option is specified during the simulation WASP will read the contents of a hydrodynamic file for unsteady flows volumes depths and velocities 5 4 Application of the Model The first step in applying the model is analyzing the problem to be solved What questions are being asked How can a simulation model be used to address these questions A water quality model can do three basic tasks de
259. owever the derivation of the finite difference form of the mass balance equation will be for a one dimensional reach Assuming vertical and lateral homogeneity we can integrate over y and z to obtain Equation 5 2 Equation 5 2 WASP Implementation of the Finite Difference Form of Mass Balance Equation Sa Wo Peal eae Con re aan Pere aod Ot Ox Ox where A cross sectional area m This equation represents the three major classes of water quality processes transport term 1 loading term 2 and transformation term 3 The finite difference form is derived in Appendix E The model network and the major processes are discussed in the following sections 5 2 The Model Network The model network is a set of expanded control volumes or segments that together represents the physical configuration of the water body As Figure 5 2 illustrates the network may subdivide the water body laterally and vertically as well as longitudinally Benthic segments can be included along with water column segments If the water quality model is being linked to the hydrodynamic model then water column segments must correspond to the hydrodynamic junctions Concentrations of water quality constituents are calculated within each segment Transport rates of water quality constituents are calculated across the interface of adjoining segments 5 3 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Model Network Figure 5 2 Model Se
260. pairs are input using the spatially variable BQ Time variable settling velocities can be specified as a series of velocities in m sec versus time If the units conversion factor is set to 1 157e 5 then these velocities are input in units of m day These velocities are multiplied internally by cross sectional areas and treated as flows that carry particulate organic matter out of the water column 8 4 3 Boundary Parameters This group of parameters includes boundary concentrations waste loads and initial conditions Boundary concentrations must be specified for any segment receiving flow inputs outputs or exchanges Initial conditions include not only initial concentrations but also the density and solids transport field for each solid and the dissolved fraction in each segment Boundary Concentrations mg L At each segment boundary time variable concentrations must be specified for CBOD NBOD and DO The NH3 system is used to represent NBOD which is expressed as TKN A boundary segment is characterized by water exchanges from outside the network including tributary inflows downstream outflows and open water dispersive exchanges Waste Loads kg day For each point source discharge time variable CBOD NBOD and DO loads can be specified These loads can represent municipal and industrial wastewater discharges or urban and agricultural runoff The NH3 system is used to represent NBOD which is expressed as TKN Solids Trans
261. patially variable parameters constants and kinetic time functions for the water quality constituents being simulated Parameter values are entered for each segment Specified values for constants apply over the entire network for the whole simulation Kinetic time functions are composed of a series of values versus time in days Water Temperature C Time and segment variable water temperatures can be specified using the parameters TMPSG and TMPEN and the time functions TEMP 1 4 as described in the modified Streeter Phelps section Sediment Oxygen Demand g m day Segment variable sediment oxygen demand fluxes and temperature coefficients can be specified using the parameters SODID and SODTA respectively Values should be entered for water column segments that are in contact with the bottom of the water body Nitrogen Mineralization Rate day The mineralization rate constant and temperature coefficient for dissolved organic nitrogen can be specified using constants K71C and K7IT respectively Nitrification Rate day The nitrification rate constant and temperature coefficient for dissolved ammonia nitrogen can be specified using constants K12C and K12T respectively CBOD Deoxygenation Rate day The CBOD deoxygenation rate constant and temperature coefficient can be specified using constants KDC and KDT respectively Reaeration Rate day There are three basic options for specifying reaeration a single rate constant
262. pecifying segment variable values for Parameter 7 FOC ISEG 1 Constant 101 LKOC should be given a small nonzero value such as 1 0e 20 If multiple solids types are being simulated then separate sets of partition coefficients may be input for each of the three solids types The constant partition coefficients for chemical 1 to solids type 2 and 3 can be input by specifying segment variable values for FOC ISEG 2 and FOC ISEG 3 Parameters 8 and 9 respectively Te 10 11 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Water Column Biodegradation Y BW Benthic Biodegradation YB Sci Alkaline Hydrolysis YHOHa Neutral Hydrolysis YHNg Acid Hydrolysis YHH Oxidation Y O X ci Photolysis Y Fa Extra Reaction YE ci Reaction Yields The input yield constants that may be specified are YHOH YHN YHH i YBW i YBS i YFe YOX and YEs where c is the chemical reactant 1 2 or 3 and 1 is the chemical product 1 2 or 3 in units of mg mg Yield coefficients may be provided for all possible combinations of chemicals and for the reactions as listed in Table 6 5 10 12 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 11 Organic Chemicals In modern technological societies synthetic organic chemicals have been manufactured used and disposed of in large quantities The large number and variety of organic compounds include such major classes as pesticides
263. phorus removal in order to keep phosphorus as the limiting nutrient DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 EFFECTS OF NUTRIENT LIMITATION ON GROWTH 1 0 0 0 8 0 2 5 3 g 06 04 ge S O 04 os ES v 0 2 0 8 E 0 1 0 DIN 0 200 400 600 800 DIP 0 8 16 24 32 Nutrient Concentration g l 4j Nitrogen Limitation 5 E u c S s 8 ba gd D amp Limitation oa c a x 2 o Figure 9 3 Effects of nutrient limitation on growth rate 9 1 6 Phytoplankton Death Numerous mechanisms have been proposed that contribute to the biomass reduction rate of phytoplankton endogenous respiration grazing by herbivorous zooplankton and parasitization The first two mechanisms have been included in previous models for phytoplankton dynamics and they have been shown to be of general importance The endogenous respiration rate of phytoplankton is the rate at which the phytoplankton oxidize their organic carbon to carbon dioxide per unit weight of phytoplankton organic carbon Respiration is the reverse of the photosynthesis process and as such contributes to the reduction in the biomass of the phytoplankton population If the respiration rate of the phytoplankton as a whole is greater than the growth rate there is a net loss of phytoplankton carbon or biomass 9 12 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 The endogenous respiration rate is temperature dependent R
264. phyll Ratio mg C mg Chl The average carbon to chlorophyll weight ratio in phytoplankton can be specified using constant CCHL A default value of 30 is provided for in EUTRO If the Smith light limitation option is chosen then CCHL will be variable recalculated daily throughout the simulation Light Limitation Available light is specified using time functions describing seasonal light at the water surface and segment and time variable light extinction coefficients These are described above The Di Toro light limitation option can be specified using a value of 1 0 for LGHTS The saturating light intensity in langleys day can then be specified using constant ISl Default values for LGHTS and IS1 are 1 and 300 respectively The Smith light limitation option can be specified using a value of 2 0 for LGHTS Two other parameters must then be specified The maximum quantum yield constant in mg C mole photons can be specified using constant PHIMX The chlorophyll extinction coefficient in mg chl a m m can be specified using constant XKC Default values for PHIMX and XKC are 720 and 0 017 respectively Nitrogen Half Saturation Constant mg N L The nitrogen half saturation constant for phytoplankton growth can be specified using constant KMNGI When inorganic nitrogen concentrations are at this level half reduces the phytoplankton growth rate This parameter also affects ammonia preference Pus as outlined in Figures 5 5 and 5 6 Wh
265. pies the GIS view to the Windows Clipboard Once in the clipboard it can be pasted into virtually another Windows program R This prints the GIS view to any printer connected to the system 4 55 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 4 4 x y Plot 4 4 1 Overview The x y plot mode represents the conventional method by which scientific data is displayed While x y plots are the conventional mode the flexibility and control the user has over the way the x y plots are configured is not The user is provided as much flexibility as possible when developing x y plots The user can plot different model results files simultaneously multiple variables and observed versus model predictions E Post processor Tampa Bay BEE E File Edt View XY Plot Window Help le x a e DO mg l AoA th A UL AAA ACT ALLER PN ANN ATTY PET TV AE Ener ee WP Fas ea RC ttt 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 Year 1989 4 4 gt p EE amp xc 941 2 B a is wl CAPS NUM OVA Aser E SA B9 Pant Shop Pro Imaget2 Er Pestprocessor ITa Bl amp 2235m Figure 4 8 Example Graph 4 4 2 Toolbar The x y plot window has its own set of controls that allows the user to perform the various options that are available The user can access these options either via the tool bar or the speed menu The following is a description of the x y plot toolbar Anima
266. piration k r 0 125 day Temperature Coefficient Ein 1 045 none Settling V elocity Vs 0 1 m day Death Rate kip 0 02 day Grazing Rate kic 0 L mgC day The nutrients are not known a priori however because they depend upon the phytoplankton population that develops These systems are interdependent and cannot be analyzed separately It is necessary to formulate a mass balance for the nutrients as well a the phytoplankton in order to calculate the chlorophyll that would develop for a given set of environmental conditions 9 1 9 Stoichiometry and Uptake Kinetics A principal component in the mass balance equations written for the nutrient systems included in the eutrophication framework is the nutrient uptake kinetics associated with phytoplankton growth To specify the nutrient uptake kinetics associated with this growth however it is necessary to specify the population stoichiometry in units of nutrient uptake mass of population synthesized For carbon as the unit of population biomass the relevant ratios are the mass of nitrogen and phosphorus per unit mass of carbon A selection of these ratios presented by Di Toro et al 1971 indicates that their variability is quite large The use of constant ratios in the analysis then is questionable Upon further investigation however it is clear that the reason these ratios vary is the varying cellular content of nutrients which is in tum a function of the external nutrient concentrations and t
267. port field one Circulation patterns may be described flow options 1 and 2 or simulated by a hydrodynamic model such as DYNHYD Flow options are specified in Section 3 13 6 1 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 For descriptive flows WASP6 tracks each separate inflow specified by the user from its point of origin through the model network For each inflow the user must supply a continuity or unit flow response function and a time function The time function describes the inflow as it varies in time The continuity function describes the unit flow response as it varies throughout the network The actual flow between segments that results from the inflow is the product of the time function and the continuity function If several inflow functions are specified then the total flow between segments is the sum of the individual flow functions Segment volumes are adjusted to maintain continuity In this manner the effect of several tributaries density currents and wind induced gyres can be described In flow Figure 3 6 Net Flow Option WASP6 sums all the flows at a segment interface to determine the direction of net flow and then moves mass in the ONE direction In Gross Flow Option WASP6 moves mass independently of net flow For example if opposite flows are specified at an interface WASP6 will move mass in BOTH directions This option allows the user to describe large dispersive circulation patterns 6
268. port Field The transport field associated with particulate CBOD and NBOD settling must be specified under initial conditions Field 3 is recommended for both Solid Density g cm A value of 0 can be entered for the nominal density of CBOD NBOD and DO This information is not used in EUTRO Initial Concentrations mg L Concentrations of CBOD NBOD and DO in each segment must be specified for the time at which the simulation begins The NH3 system is used to represent NBOD which is expressed as TKN Concentrations of zero for non simulated variables NO3 PO4 PHYT ON and OP will be entered by the preprocessor Dissolved Fraction The dissolved fraction of CBOD NBOD and DO in each segment must be specified Values for DO should be 1 0 Only the particulate fraction of CBOD and NBOD will be subject to settling 8 21 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 8 4 4 Transformation Parameters This group of parameters includes spatially variable parameters constants and kinetic time functions for the water quality constituents being simulated Parameter values are entered for each segment Specified values for constants apply over the entire network for the whole simulation Kinetic time functions are composed of a series of values versus time in days Water Temperature C Time and segment variable water temperatures can be specified using the parameters TMPSG and TMPEN and the time functions
269. presented above with the following Nitrification Rate day The nitrification rate constant and temperature coefficient for dissolved ammonia nitrogen can be specified using constants K12C and KI2T respectively The half saturation constant for oxygen limitation of nitrification can be specified using constant KNIT The default value for KNIT is 0 0 indicating no oxygen limitation Denitrification Rate day The denitrification rate constant and temperature coefficient for dissolved nitrate nitrogen can be specified using constants K20C and K2OT respectively The half saturation constant for oxygen limitation of denitrification can be specified using constant KNO3 The default value for KNO3 is 0 0 indicating no denitrification at oxygen concentrations above 0 0 CBOD Deoxygenation Rate day The CBOD deoxygenation rate constant and temperature coefficient can be specified using constants KDC and KDT respectively The half saturation constant for oxygen limitation of carbonaceous deoxygenation can be specified using constant KBOD The default value for KBOD is 0 0 indicating no oxygen limitation 8 27 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 9 Eutrophication Nutrient enrichment and eutrophication are continuing concerns in many water bodies High concentrations of nitrogen and phosphorus can lead to periodic phytoplankton blooms and an alteration of the natural trophic balance Dissolved oxygen levels
270. pressed If the user is closer to the Y axis and presses the right mouse button and drags a box vertically it assumes the user wants to zoom the Y axis The converse is true for the y axis If the user is closer to the xaxis and drags a box horizontally it is assumed the user wants to zoom the x axis 4 70 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 E Post processor Tampa Bay BEE E File Edt View XY Plot Window Help 218 x A A Tg A LI BEI M LT AA A TE LAUA AS TY Loar eae 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 Year 1989 4 4 amp x 9 lt a Ea ta ez a CAPS NUM OVA Astan E 17 S X Point Shop Pro Imaget Ez Post processor Ta _ Bl amp 226PM Figure 4 18 Zoomed y Axis Note If the user is having trouble controlling which axis to zoom the speed menu allows the user to select which axis to zoom 4 4 6 Adding an Additional Curve The user has the option of adding as many curves as desired to any given x y plot window There is no limit to the number of curves that can be defined It is recommended that no more than five curves be defined for a given x y plot as resolution and comprehension will be diminished Note The user can create as many curves per x y plot and x y plot windows as desired 4 71 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 4 4 7 Color Black amp White View The x
271. put cannot be made using the internal CBOD computed by EUTRO since field measurements may be tainted by algal 8 8 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 respiration and the decay of algal carbon Therefore a correction must be made to the internally computed model CBOD so that a valid comparison to the field measurement may be made This results in a new variable known as the bottle BODs which is computed via equation 4 10 Equation 8 10 64 Bottle BOD C5 1 go P C knbor ta oc C e SEN where C the internally computed CBO D mg L C the internally computed NH mg L C the phytoplankton biomass in carbon units mg L aoc the oxygen to carbon ratio 32 12 mg O mg C Kabot the laboratory bottle deoxygenation rate constant day Kabot the laboratory bottle nitrification rate constant day kir the algal respiration rate constant at 20 C day Equation 8 11 can provide a low estimate of the observed bottle BOD because it does not include a correction for the decay of detrital algal carbon which in turn depends upon the number of non viable phytoplankton Please note that laboratory bottle CBOD and nitrification rates are used here as specified by the user The default laboratory rate constant for nitrification is O reflecting the use of a nitrifying inhibitor 8 2 3 Nitrification Additional significant losses of oxygen can occur as a result of nitrification
272. quation 9 11 Equation 9 11 KeD gode Pack Z2 l kic X rre K D 9 9 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 where the latter term is the average daily solar radiation within a segment during daylight hours in ly day Note that substituting Equation 5 11 into 5 8 gives an I equal to 30 of the average available light A review of reported carbon chlorophyll ratios in nature Eppley and Sloane 1966 suggests that physiological factors in part the energy cost of synthesizing chlorophyll as compared with other cellular compounds come into play to prevent E from going much below 20 even in very low light This lower limit of 20 has been included when determining a value for e Previously reported values of E from algal composition studies conducted by EPA Region III s Central Regional Laboratory CRL are compared in Table 5 2 to calculated values of using Equation 5 11 There is general agreement between the measured and calculated values Unfortunately no winter algae composition studies were available for comparison purposes Nutrients The effects of various nutrient concentrations on the growth of phytoplankton have been investigated and the results are quite complex As a first approximation to the effect of nutrient concentration on the growth rate it is assumed that the phytoplankton population in question follows Monod growth kinetics with respect to the important nutrients That is at an a
273. quations divide biochemical oxygen demand into carbonaceous and nitrogenous fractions and allow time variable temperatures to be specified This allows for more realistic calibration to observed data Waste load allocations however are usually projected for design low flow conditions Figure 8 5 8 18 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Use System 1 Ammonia Benthic Sediment 1 Reaeration 2 Sediment Oxygen Demand 3 Carbonaceous Deoxygenation 4 Settling and Deposition of Organic Material 5 Nitrogenous Deoxygenation Figure 8 5 Modified Streeter Phelps Equation 8 17 Se ku 9 C f C Equation 8 18 Su7 k 8 C 3 f C 8 19 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 8 19 Sw t k 2077 C Cs k 057 C 64 SOD k On c 07 14 Be weet where Sy is the source sink term for variable i in a segment in mg L day Kinetic rate constants and coefficients are as defined in Table 4 1 except for the following C nitrogenous biochemical oxygen demand NBOD as expressed by TKN mg L use System 1 k nitrogenous deoxygenation rate constant day E temperature coefficient f NBOD dissolved fraction To implement these equations in EUTRO System 1 nominally NH3 must be interpreted as nitrogenous BOD rather than ammonia Here NBOD is expressed by total Kjeldahl nitrogen TKN If directly measured
274. r networks composed of water column segments only Spatially variable observed fluxes must be specified for ammonia phosphate and sediment oxygen demand Time functions may be specified for ammonia and phosphate reflecting seasonal changes Seasonal changes in water temperature can affect SOD through its temperature coefficient Sediment Water Exchange Water Column 12 3 l Ammonia Flux F yy Surface Area TFNH 2 Phosphate Load Fyg Surface Area TFPO 3 Dissolved Oxygen Load SOD Surface Area Theta Benthic Segment 12345678 Figure 9 7 Sediment Water Exchange 9 27 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 9 4 2 Benthic Simulation The calculational framework incorporated for benthic water column exchange draws principally from a study of Lake Erie which incorporated sediment water column interactions performed by Di Toro and Connolly 1980 For a surficial benthic layer with thickness D the nitrogen and phosphorus mass balance equations are summarized in Figure 9 8 and Table 9 6 The benthic CBOD and DO equations were summarized in Figure 8 4 and Table 8 2 in the previous chapter Organic Nitrogen oC P T 20 4 T 20 8 ke OP a Son Ca konn Dono C t Plgaldacomporiton Mire ralisstion Ammonia Nitrogen oC l 7 20 T 20 we Mm Opp Ane L fon Ca Kann Gann C flgldecomporition Mineralization Nitrate Nitrogen ac 2 T 2 kyp e E Ca at Denitrification Organi
275. r will be able to select the segment to define the load There will be an entry for every segment in which the user wants to define a load The user can delete a load by selecting the system right mouse click and select delete 3 28 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WINAWASP Standard C Program Files AS cl WinWaspS tandard examples example wif Tampa Input Data Set EUTRO FEI E3 File Project Pre processor Model Post Processor Help Cf GeO Se me E a OPE Loads Scale and Conversion Factors Y Orthophosphate a Wasp Segment a Wasp Segment amp Wasp Segment a Wasp Segment a Wasp Segment a Wasp Segment e Wasp Segment a Wasp Segment a Wasp Segment So Wasp Segment zi Time functions for segment 1 Wasp Segment Orthophosphate Dae Time I 1 1 1985 12 00 AM 60 5600 123171985 12 00 4M 58 0200 3 2 1985 12 00 AM 72 6000 4 1 1985 12 00 4M 47 0600 5 1 1885 12 00 AM 32 8400 5 31 1985 12 00 AM 195 2500 ft Graph Fi Cak as Mstat E Sy AY By Microsoft Word W BaPink Microsoft Out B PaintShopPro Aser winzwa BI amp 10 21 AM Figure 3 16 Waste Load Definition Screen 3 14 1 Load Time Function The time function table allows the user to enter time variable loadings kg day The user must provide the date time and concentration
276. ral physical chemical processes can affect the transport and interaction among the nutrients phytoplankton carbonaceous material and dissolved oxygen in the aquatic environment Figure 8 1 presents the principal kinetic interactions for the nutrient cycles and dissolved oxygen 8 1 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Atmosphere 02 Figure 8 1 EUTRO State Variable Interactions EUTRO can be operated by the user at various levels of complexity to simulate some or all of these variables and interactions To simulate only carbonaceous biochemical oxygen demand BOD and DO for example the user may bypass calculations for the nitrogen phosphorus and phytoplankton variables Simulations may incorporate carbonaceous biochemical oxygen demand CBOD and either ammonia NH3 or nitrogenous biochemical oxygen demand NBOD expressed as ammonia Sediment oxygen demand may be specified as well as photosynthesis and respiration rates Four levels of complexity are identified and documented at the end of this section 1 Streeter Phelps 2 modified Streeter Phelps 3 full linear DO balance and 4 nonlinear DO balance The actual simulation of phytoplankton is described in Chapter 5 8 2 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 8 2 Dissolved Oxygen Processes Five EUTRO state variables can participate directly in the DO balance phytoplankton carbon ammonia nitrate car
277. ram WASP Version 6 0 If the user wants to enter time variable extinction coefficients then values for the parameter KESG should be set to 1 0 The parameter KEFN indicates which light extinction function will be used by the model for each segment Values of 1 0 2 0 3 0 4 0 or 5 0 will call time functions KE 1 KE 2 KE 3 KE 4 and KE 5 respectively Light extinction coefficients should then be entered via these time functions as a series of coefficient versus time values The product of KESG and the selected KE function will give the segment and time specific light extinction coefficients used by EUTRO KESG and KEEN are identified in EUTRO as parameters 5 and 6 respectively KE 1 4 are identified in EUTRO as time functions 8 12 Growth Rate day The maximum phytoplankton growth rate constant and temperature coefficient can be input using constants K1C and KIT respectively Carbon to Chlorophyll Ratio mg C mg Chl The average carbon to chlorophyll weight ratio in phytoplankton can be specified using constant CCHL A default value of 30 is provided for in EUTRO Light Limitation Available light is specified using time functions describing seasonal light at the water surface and segment and time variable light extinction coefficients These are described above The Di Toro light limitation option can be specified using a value of 1 0 for LGHTS The saturating light intensity can then be specified using constant IS1 Default
278. ransfer processes defined in the model include sorption and volatilization Transformation processes include biodegradation hydrolysis photolysis and oxidation Sorption is treated as an equilibrium reaction The simplified transformation processes are described by first order rate equations WASP6 uses a mass balance equation to calculate sediment and chemical mass and concentrations for every segment in a specialized network that may include surface water underlying water surface bed and underlying bed In a simulation sediment is advected and dispersed among water segments settled to and eroded from benthic segments and moved between benthic segments through net sedimentation erosion or bed load as detailed in Chapter 7 Simulated chemicals undergo several physical or chemical reactions as specified by the user in the input dataset Chemicals are advected and dispersed among water segments and exchanged with surficial benthic segments by dispersive mixing Sorbed chemicals settle through water column segments and deposit to or erode from surficial benthic segments Within the bed dissolved chemicals migrate downward or upward through percolation and pore water diffusion Sorbed chemicals migrate downward or upward through net sedimentation or erosion Rate constants and equilibrium coefficients must be estimated from field or literature data in simplified toxic chemical studies Some limitations should be kept in mind when applying TOX
279. raph 3 20 Validity Check The validly check makes a check of the user provided input data to make sure there are no troubles This is quick way to make sure all your data is correct and within the dimensioned capabilities of the selected model type 3 38 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WIN AWASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO File Project Pre processor Model Post Processor Help Validity check passed No problems were detected SSS ee eee Mstart E 2 A 89 Paint Shop Pro Imege23 s ASci WIN WASP EE 1031 4m Figure 3 26 Dataset Validity Check If a problem occurs during the validity check the information is passed to the user If no problems are found the user should press the Okay button 3 21 Model Execution To execute the loaded input dataset the user should press the Model Execution icon on the main toolbar WASP6 loads the appropriate model DLL TOXI EUTRO based upon the model type set by the user in the Model Parameterization entry form Note Before you can run the model you must have an input dataset open in WASP6 3 39 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WIN WASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO md x File Project Pre processor Model PostProcessor Help E gt Begin Execution of WASP EF
280. rce of oxygen from phytoplankton growth occurs when the available ammonia nutrient source is exhausted and the phytoplankton begins to utilize the available nitrate For nitrate uptake the initial step is a reduction to ammonia that produces oxygen 8 10 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 8 13 2NO 2NH 30 Thus for each mg of phytoplankton carbon produced by growth using nitrate anc mg of phytoplankton nitrogen are reduced and 48 14 anc mg of O are produced Phytoplankton Respiration Oxygen is diminished in the water column as a result of phytoplankton respiration which is basically the reverse process of photosynthesis Equation 8 14 C4 t05 CO where C4 is phytoplankton carbon in mg L Thus for every mg of phytoplankton carbon consumed by respiration 32 12 mg of oxygen are also consumed 8 2 7 Phytoplankton Death The death of phytoplankton provides organic carbon which can be oxidized The kinetic expression in EUTRO recycles phytoplankton carbon to CBOD using a first order death rate and the stoichiometric oxygen to carbon ratio 32 12 8 2 8 Sediment Oxygen Demand The decomposition of organic material in benthic sediment can have profound effects on the concentrations of oxygen in the overlying waters The decomposition of organic material results in the exertion of an oxygen demand at the sediment water interface As a result the areal fluxes from the sediment
281. re Ci drag coefficient 0 0011 Wio wind velocity 10 m above water surface m sec D density of air internally calculated from air temperature 11 24 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 kg m Dy density of water internally calculated from water temperature kg m von K armen s constant 0 74 amp dimensionless viscous sublayer thickness 4 Sca and Sew are air and water Schmidt Numbers computed from Equation 11 52 M PaDa S ca Equation 11 53 S cw E p w D w where D diffusivity of chemical in air m sec D E diffusivity of chemical in water m7 sec li viscosity of air internally calculated from air temperature kg m sec li viscosity of water internall calculated from water temperature kg m sec The diffusivity of the chemical in water is computed using Equation 7 48 while the diffusivity of the chemical in air Da nr sec is computed from Equation 11 54 1 9 0 E M a Thus Kg is proportional to wind and inversely proportional to molecular weight to the 4 9 power 11 6 6 Volatilization Option 5 As with Option 4 the liquid and gas film transfer coefficients computed under this option vary with the type of waterbody The type of waterbody is specified to the water as one of the volatilization constants and can either be a flowing stream river or estuary or a stagnant pond or lake The primary difference is that in
282. re supplied in the program as data statements in subroutine BEER and are shown in Tables 7 12 and 7 13 Segment average photolysis rate constants are computed for each wavelength and then summed to yield an overall rate 11 8 3 Photolysis Option 2 Under this option a reference surface sunlight absorption rate kari E mole day is input by the user for each specie simulated As with EXAMSII the input rate is then adjusted as shown below Equation 11 66 ka Y Y kari Tol Ic Io 1 0 056 C Xi i j where uS user specified normalized light intensity time function which is the ratio of ambient light intensity to the reference light intensity C cloud cover in tenths 0 10 latitude correction factor calculated by Equation 11 67 P lt Ha II xus 19169 65 87054 63 cos 0 059 L 19169 65 87054 63 cos 0 039 Lps where L latitude of the waterbody Le reference latitude at which the surface photolysis rate was measured The average light intensity attenuation Ic I is computed as above from the Beer Lambert formulation equation 7 65 Therefore the light intensity has a value for each model segment ranging from zero to one The extinction coefficient may be directly specified as a model parameter which may be varied by model segment If the extinction coefficient is not specified it is determined from a user specified wavelength of maximum light absorption for the particular chemical species neutral a
283. reaction terms Value from Potomac Estuary Model D escription Notation Units Nitrogen to carbon ratio anc 0 25 mg N gm C Organic nitrogen mineralization rate kn 0 075 day 20 C Temperature coefficient En 1 08 Nitrification rate ki 0 09 0 13 day Temperature coefficient E12 1 08 3 Half saturation constant for oxygen Knir 2 0 mg 02 L 9 22 DRAFT Water Quality Analysis Simulation Program WASP limitation of nitrification Denitrification rate at kop 20 C Temperature coefficient m Michaelis constant for denitrification K No3 Fraction of dead and respired phytoplankton recycled to the organic nitrogen pool fon to the ammonia nitrogen pool 1 fon Preference for ammonia uptake term PNH3 Fraction dissolved organic nitrogen fp7 Organic matter settling velocity Vs 9 3 1 Phytoplankton Growth Version 6 0 0 09 day 1 045 0 1 mg O2 L 05 05 eq 5 30 1 0 m day As phytoplankton grow dissolved inorganic nitrogen is taken up and incorporated into biomass For every mg of phytoplankton carbon produced a c mg of inorganic nitrogen is taken up Both ammonia and nitrate are available for uptake and use in cell growth by phytoplankton however for physiological reasons the preferred form is ammonia nitrogen The ammonia preference term Pw is given in Figure 9 6 9 23 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Ammonia Preference Structure K mu 25 ig 1 0 z 0 8 100 p
284. rise above 0 The user may specify the half saturation constant Kno3 which represents the DO level at which the denitrification rate is reduced by half The default value is zero which prevents this reaction at all DO levels 8 2 5 Settling Under quiescent flow conditions the particulate fraction of CBOD can settle downward through the water column and deposit on the bottom In water bodies this can reduce carbonaceous deoxygenation in the water column significantly The deposition of CBOD and phytoplankton however can fuel sediment oxygen demand in the benthic sediment Under high flow conditions particulate CBOD from the bed can be resuspended The kinetic expression for settling in EUTRO is driven by the user specified particulate settling velocity v and the CBOD particulate fraction 1 fps where fps is the dissolved fraction Settling velocities that vary with time and segment can be input as part of the advective transport field Resuspension can also be input using a separate velocity time function Segment variable dissolved fractions are input with initial conditions 8 2 6 Phytoplankton Growth A byproduct of photosynthetic carbon fixation is the production of dissolved oxygen The rate of oxygen production and nutrient uptake is proportional to the growth rate of the phytoplankton since its stoichiometry is fixed Thus for each mg of phytoplankton carbon produced by growth 32 12 mg of O are produced An additional sou
285. rk that may include surface water underlying water surface bed and underlying bed In a simulation sediment is advected and dispersed among water segments settles to and erodes from benthic segments and moves between benthic segments through net sedimentation erosion or bed load Chapter 3 details the TOXI sediment transport processes In a simulation the chemical can undergo several physical or chemical transformations It is convenient to group these into fast and slow reactions Fast reactions have characteristic reaction times that are much faster than or on the same order as the model time step and are handled with the assumption of local equilibrium Slow reactions have characteristic reaction times much longer than the model time step These are handled with the assumption of local first order kinetics using a lumped rate constant specified by the user or calculated internally based on summation of several process rates some of which are second order Thus the effective first order decay rate can vary with time and space and is recalculated as often as necessary throughout a simulation The chemical is advected and dispersed among water segments and exchanged with surficial benthic segments by dispersive mixing Sorbed chemical settles through water column segments and deposits to or erodes from surficial benthic segments Within the bed dissolved chemical migrates downward or upward through percolation and pore water diffusion
286. rmation needed to simulate algae e Bypassed indicates to WASP that NO calculations should be done for the particular system When a system is bypassed in WASP the user does not have to provide boundary concentrations or initial conditions When bypassing systems in WASP make sure that you are not removing an integral part of the problem you are trying to solve For both the advective and dispersive transport functions in WASP the user has the ability to bypass the effect of the particular transport phenomenon on the particular state variable in WASP If the user would like to see the effect of algae on the system when it is not allowed to transport the user sets the bypass flag for Chlorophyll a to Y in either advection or dispersion possibly both 3 8 2 Dispersion Flow Bypass The dispersion flow bypass option allows the user to specify whether a state variable will transport by either one of these processes If the user did not want a state variable to be affected by dispersion or flow they should check the appropriate box 3 8 3 Density The density of each constituent must be specified under initial conditions as well g em 3 8 4 Maximum Concentration The maximum concentration column allows the user to specify what would be the expected maximum concentration mg l of any of the given state variables If WASP6 predicted a concentration greater than the supplied value here the model simulation would be terminated 3 8 5
287. rom solids DOC and chlorophyll a concentrations for the wavelength of maximum absorption DOC and chlorophyll a are specified as model parameters 11 42 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 which may vary between segments and over time Their input is describe in the Photolysis Option 1 section above Light is set to zero under ice cover which is assumed when water temperatures reach 0 C 11 9 Oxidation Chemical oxidation of organic toxicants in aquatic systems can be a consequence of interactions between free radicals and the pollutants Free radicals can be formed as a result of photochemical reactions Free radicals that have received some attention in the lterature include alkylperoxy radicals RO2 OH radicals and singlet oxygen 11 9 1 Overview of TOXI Oxidation Reactions In TOXL oxidation is modeled as a general second order process for the various species and phases of each chemical Equation 11 68 K ROYYkaufs py where K net oxidation rate constant day RO molar concentration of oxidant moles L kj second order oxidation rate constant for chemical as specie i in phase j L mole day The reaction coefficients may be specified as constants with activation energy constants left as 0 If the user wants TOXI to determine rates based on the temperature based Arrhenius function then non zero activation energies specified as constants will invoke the following calculation
288. rowth rate over depth Equation 9 4 f erp Lop D oxp Ss e K D p S where L the average incident light intensity during daylight hours just below the surface assumed to average 0 9 I f ly day L the saturating light intensity of phytoplankton ly day the light extinction coefficient computed from the sum of the non algal light attenuation K and the phytoplankton self shading attenuation K na as calculated by Equation 5 5 m Equation 9 5 K sna 0 0088 Pen 0 054 POI Pon phytoplankton chlorophyll concentration jig L Typical clear sky values of surface light intensity for different latitudes and months are provided in Table 9 1 Table 9 1Example Solar Radiation Time Annual of Day Season Mean Latitude Spring Summer Fall Winter 30 N Mean 680 750 530 440 600 Mid D ay 2100 2200 1700 1400 1900 40 N Mean 650 740 440 320 540 Mid D ay 1900 2100 1400 1000 1600 50 N Mean 590 710 330 190 460 Mid Day 1700 1900 1000 650 1300 9 7 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 calculated seasonal means under a clear sky representing upper limits for solar radiant energy at sea level Reference Weast and Astle 1980 Mid day flux extended over a 24 hour period assuming an atmospheric turbidity of 0 precipitable water content of 2 cm and atmospheric ozone content of 34 cm NTP Reference Robinson 1966 Equation 9 4 is quite similar in
289. rporated into the modeling framework Now there is no distinction between the model and the preprocessor In fact the eutrophication 3 4 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 model is a dynamic link library DLL that is executed by the preprocessor WASP no longer requires input files the data needed to execute the model is passed to the model DLL using dynamic data exchange The model input dataset reading routines have been removed from the model This was done to make a more efficient means of storing the model input dataset and not worrying about all of the formatting issues associated with the DOS based model 3 2 Installation The WASP6 installation is accomplished much like any other Windows software installation To initiate the installation 1 Place the WASP6 CD in your CD ROM drive 2 Select Start Run from the Windows menu 3 Enter d setup If your CD ROM drive is not drive D type the appropriate letter instead 4 Choose OK 5 Follow the instructions on the screen prompts to complete the installation 3 8 Technical Support 3 4 Tool Bar Definition When the user first loads WASP6 a toolbar is displayed This toolbar allows the user to navigate the different options and data entry forms of the program Depending upon the settings in the User Preferences Figure 3 3 some or all the toolbar icons are visible If a toolbar icon is visible but not colored this indicates that the
290. s 11 7 1 Overview of TOXI Hydrolysis Reactions Version 6 0 11 7 2 Option 1 First Order Hydrolysis 11 7 3 Option 2 Second Order Hydrolysis 11 8 Photolysis 11 8 1 Overview of TOXI Photolysis Reactions 11 8 2 Photolysis Option 1 11 8 3 Photolysis Option 2 11 8 4 Photolysis Option 1 11 8 5 Photolysis Option 2 11 9 Oxidation 11 9 1 Overview of TOXI Oxidation Reactions 11 10 Biodegradation 11 10 1 Overview of TOXI Biodegradation Reactions 11 11 Extra Reaction 11 11 1 Overview of TOXI Extra Reaction 12 REFERENCES DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 1 Forward WASP6 is an enhanced Windows version of the USEPA Water Quality Analysis Simulation Program WASP WASP6 has been developed to aid modelers in the implementation of WASP WASP6 has features including a pre processor a rapid data processor and a graphical post processor that enable the modeler to run WASP more quickly and easily and evaluate model results both numerically and graphically With WASP6 model execution can be performed up to ten times faster than the previous USEPA DOS version of WASP Nonetheless WASP6 uses the same algorithms to solve water quality problems as those used in the DOS version of WASP WASP6 contains 1 a user friendly Windows based interface 2 a pre processor to assist modelers in the processing of data into a format that can be used in WASP 3
291. s compressed to the density of the lower bed Since the porosity of the uncompressed bed is greater than the porosity of the compressed bed pore water and dissolved chemical are squeezed into the water column 85 ag 0 WATER COLUMN SURFACE 2 BED SUBSURFACE BED burial M Figure 7 2 WASP Sediment Burial During compression the lower bed segments rise to include the compressed portion of the upper bed The volumes and sediment concentrations of these lower bed segments remain constant A portion of the bottom bed segment is buried out of the network however as bed segments rise in response to sedimentation Thus chemical mass in the lower bed is added through compression of the upper bed and lost through sediment burial After compression the top bed segment returns to its original predeposition volume Sediment and chemical concentrations in the upper bed are not changed by compaction In the lower beds segment volumes and sediment concentrations are unchanged Chemical mass from the compacted portion of the bed is added to the lower bed and chemical mass in the bottom bed segment is buried out of the model network 7 7 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Over several sedimentation time steps the density and volume of the upper bed segment remain constant so that Equation 7 8 OY S Sts Ay wo Sj Aj wet ws S 9 and Equation 7 9 ws wp Si wn SiY Si F
292. s of interfaces in which the user can enter the information mouse and digitizer tablet If the user has access to a digitizer this is probably the most advantageous mode for generating BMG files With Mouse The mouse interface allows the user to develop the model grid by drawing the model network using the mouse Each computational element being defined in the model network needs to be represented by an individual polygon To use Digitize with the mouse interface the program needs to be loaded with the m command line parameter This instructs Digitize to get the drawing information from the mouse With Digitizer The digitizer interface allows the user to develop the model grid by actually rendering the model network using a digitizer tablet This is probably a more exact way of developing the model spatial grid The digitizer interface allows the user to take engineering drawings of the waterbody and lay the model network right on top When using the digitizer interface the user needs to instruct Digitize as to the communication port from which to read the information This is done by using a command line parameter COM2 which instructs Digitize to get the information from the digitizer tablet from communication port 2 4 3 5 Controlling Spatial Analysis Each of the spatial grid analysis windows can be configured several different ways to display the model results The user can elect to display results in one of three animation modes 1
293. s set to 0 the second option is attempted by EUTRO In this option variable reaeration rate constants can be input using parameter REARSG and time function REAR The product of spatially variable REARSG and time variable REAR gives the segment and time specific reaeration rate constants used by EUTRO These reaeration values are not modified by a temperature function The third option is invoked if neither K2 nor REARSG is entered In this option reaeration rates will be calculated from water velocity depth wind velocity and water and air temperature The actual reaeration rate used by EUTRO will be either the flow or wind induced value whichever is largest For rivers segment water velocities and depths are calculated as a function of flow using the hydraulic coefficients entered under the topic environment For lakes and estuaries ambient velocities in m sec can be input using parameter VELEN and time functions VEL 1 4 The parameter VELEN indicates which velocity function will be used by the model for each segment Values of 1 0 2 0 3 0 or 4 0 will call time functions VELN 1 VELN 2 VELN 3 and VELN 4 respectively Water velocities should then be entered via these time functions as a series of velocity versus time values For open bodies of water wind driven reaeration can be significant The user should input ambient wind speed in m sec and air temperature in C using time functions WIND and AIRTMP The default values for
294. scribe present water quality conditions provide generic predictions and provide site specific predictions The first descriptive task is to extend in some way a limited site specific database Because monitoring is expensive data seldom give the spatial and temporal resolution needed to fully characterize a water body A simulation model can be used to interpolate between observed data locating for example the dissolved oxygen sag point in a river or the maximum salinity intrusion in an estuary Of course such a model can be used to guide future monitoring efforts Descriptive models also can be used to infer the important processes controlling present water quality This information can be used to guide not only monitoring efforts but also model development efforts Providing generic predictions is a second type of modeling task Site specific data may not be needed if the goal is to predict the types of water bodies at risk from a new chemical A crude set of data may be adequate to screen a list of chemicals for potential risk to a particular water body Generic predictions may sufficiently address the management problem to be solved or they may be a preliminary step in detailed site specific analyses Providing site specific predictions is the most stringent modeling task Calibration to a good set of monitoring data is definitely needed to provide credible predictions Because predictions often attempt to extrapolate beyond the present data
295. scribed above to analyze eutrophication problems For convenience three levels of complexity are identified here 1 simple eutrophication kinetics 2 intermediate eutrophication kinetics and 3 intermediate eutrophication kinetics with benthos Please note that the discrete levels of simulation identified here are among a continuum of levels that the user could implement The three implementation levels are described briefly below along with the input parameters required to solve the eutrophication equations in EUTRO Input parameters are prepared for WASP6 in four major sections of the preprocessor environment transport boundaries and transformation Basic model parameters are described in Chapter 5 and will not be repeated here The eight state variables with abbreviations used in this text are listed in Table 9 7 Table 9 7 Summary of EUTRO variables Variable Notation Concentration Units 1 Ammonia Nitrogen 2 Nitrate Nitrogen 3 Inorganic Phosphorus 4 Phytoplankton Carbon 5 Carbonaceous BOD 6 Dissolved Oxygen 7 Organic Nitrogen 8 Organic Phosphorus 9 32 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 9 6 Simple Eutrophication Kinetics Simple eutrophication kinetics simulates the growth and death of phytoplankton interacting with one of the nutrient cycles Growth can be limited by the availability of inorganic nitrogen or inorganic phosphorus and light Equations include phytop
296. se time functions as a series of velocity versus time values Water Body Type see Option 2 above Ratio of Volatilization to Reaeration see Option 2 above Molecular Weight g mole see Option 2 above Wind Speed m sec see Option 2 above 11 29 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Air Temperature C see Option 2 above 11 6 11 Volatilization Option 5 In this option volatilization rates in flowing systems are calculated using reaeration rates calculated from Covar s method and a gas transfer rate of 100 m day In quiescent systems volatilization is computed from MacKay s equations for liquid and gas transfer Input data required for option 5 are the same as for option 4 above For flowing systems wind speed and air temperature are not used and may be omitted For quiescent systems water velocity may be omitted 11 7 Hydrolysis Hydrolysis or reaction of the chemical with water is known to be a major pathway for degradation of many toxic organics Hydrolysis is a reaction in which cleavage of a molecular bond of the chemical and formation of a new bond with either the hydrogen or the hydroxyl component of a water molecule occurs Hydrolytic reactions are usually catalyzed by acid and or base and the overriding factor affecting hydrolysis rates at a given temperature is generally hydrogen or hydroxide ion concentration Wolfe 1980 An example reaction is shown in 8 The reaction can be cata
297. se to net deposition Cross Sectional Areas m The interfacial surface area must be specified for adjoining segments where sediment transport occurs These surface areas are multiplied internally by sediment transport velocities to obtain sediment transport flows Number of Exchange Fields Under dispersion the user has a choice of up to two exchange fields To simulate surface water toxicant and solids dispersion select water column dispersion To simulate exchange of dissolved toxicants with the bed the user should also select pore water diffusion Water Column Dispersion m sec Time variable water column dispersion can be specified as detailed in Chapter 2 Pore Water Diffusion Coefficients m sec Time variable pore water diffusion coefficients can be specified for dissolved toxicant exchange within the bed or between the bed and the water column If the units conversion factor is set to 1 157e 5 then these coefficients are input in units of m day Diffusion coefficients are multiplied internally by cross sectional areas divided by characteristic mixing lengths and are treated as flows that carry dissolved toxicants between benthic segments and the water column 10 8 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Cross Sectional Areas m The interfacial surface area must be specified for adjoining segments where pore water diffusion occurs These surface areas are multiplied internally
298. se water quality conditions change rapidly near a loading point and stabilize downstream studying the effects on a beach a quarter mile downstream of a discharge requires smaller segments than studying the effects on a beach several miles away A final general guideline may be helpful in obtaining accurate simulations water column volumes should be roughly the same If flows vary significantly downstream then segment volumes should increase proportionately The user should first choose the proper segment volume and time step in the critical reaches of the water body Ve At and then scale upstream and downstream segments accordingly V V Q Q Of course actual volumes specified must be adjusted to best represent the actual spatial variability as discussed above This guideline will allow larger time steps and result in greater numerical accuracy over the entire model network as explained in the section on Simulation Parameters in Chapter 2 5 8 The Model Transport Scheme Transport includes advection and dispersion of water quality constituents Advection and dispersion in WASP are each divided into six distinct types or fields The first transport field involves advective flow and dispersive mixing in the water column Advective flow carries water quality constituents downstream with the water and accounts for instream dilution Dispersion causes further mixing and dilution between regions of high concentrations and regions of l
299. sec 0 0 95 180 320 420 480 0 2 55 100 160 180 160 0 3 35 60 80 60 0 0 4 15 20 0 At 2000 sec 0 0 90 160 240 240 160 0 1 70 120 160 120 0 0 2 50 80 80 0 0 3 30 40 0 0 4 10 0 At 4000 sec 0 0 80 120 80 0 1 60 80 0 0 2 40 40 0 3 20 0 0 4 0 At 8000 sec 0 0 60 40 0 1 40 0 0 2 20 0 3 0 0 4 Note that a 6 of O reduces this to Equation 6 20 Values of Kum for a length of 2000 meters and various combinations of velocity and time step are provided in Table 6 3 For a particular velocity say 0 4 m sec numerical increasing the time step can reduce dispersion For 6 0 increasing the time step from 1000 to 4000 seconds decreases Enum from 320 to 80 nf sec If the time step must be 1000 seconds however increasing 6 can still reduce numerical dispersion In this case increasing 6 from O to 0 4 decreases Kum from 320 to 0 m sec Group A Record 4 ADFC Initial Time day hour minute the time at the beginning of the simulation must be specified in order to synchronize all the time functions The day hour and minute can be input The beginning of the simulation is day 1 Figure 3 6 Final Time days The elapsed time at the end of the simulation must be specified The end of the simulation occurs when the final time from the integration time step history is encountered The final time is entered on the same record as the time step Figure 3 18 Integration Time Step days A sequence of integration tim
300. sed with a user defined optical path d to calculate the specific sunlight absorption rate The first order rate constant is then calculated using equation 7 63 This calculation was taken directly from EXAMS II Burns and Cline 1985 and is based on formulations published by Green Cross and Smith 1980 The specific sunlight absorption rate is the integral or summation over all bandwidths of the average light multiplied by the molar absorptivity and the optical path Equation 11 63 ka Y I c u d 2303 86400 6 022 x 107 k where Ts average light intensity of wavelength k photons cm sec ai decadic molar absorptivity of wavelength k by specie i L mole cm In 10 d ratio of the optical path to the vertical path cm cm 2303 cm L In 10 In e 86400 sec day 6 022x 10 Avagadro s number photons E 11 35 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Light extinction is calculated with the integrated Beer Lambert formulation for each wavelength k Equation 11 64 Ig l exp d K D I ok d K D where Le light intensity of wavelength k just below water surface photons cm sec K spatially variable light extinction coefficient m D depth of water segment m Specific Light Extinction Coefficients Pure Water Chlorophyll DOC Solids Number Wavelength lm L gm m L mgm L mgm 1 280 0 0 288 145 7 90 0 34 2 282 5 0 268 138 7 65 0 34 3 285 0 0 249 132 741 0 34 4 287 5
301. sediment transport fields Finally the user must simulate sediment as a state variable in order to use this option Sediment is a state variable in the toxics program but not the eutrophication program 7 8 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 7 2 Model Implementation To simulate sediment transport with WASP6 use the preprocessor or a text editor to create a TOXI input file Simple datasets are provided for use as templates to edit and adapt The model input dataset and the input parameters will be similar to those for the conservative tracer model as described in Chapter 6 To those basic parameters the user will add benthic segments and solids transport rates During the simulation solids variables will be transported both by the water column advection and dispersion rates and by these solids transport rates In WASPSO solids transport rates in the water column and the bed are input via up to three solids transport fields These fields describe the settling deposition scour and sedimentation flows of three kinds of solids The transport of particulate chemicals or the particulate fraction of simulated chemicals follows the solids flows The user must specify the dissolved fraction i e 0 0 and the solids transport field for each simulated solid under initial conditions To simulate total solids solids 1 must be used 7 2 1 Model Input Parameters This section summarizes the input parameters that mu
302. several options available to indicate the desire to perform a zoom function If only one y axis has been defined the axis can be zoomed just like the X To zoom the yaxis place the mouse cursor close to the y axis line within the plot area at the beginning concentration of the area To zoom press and hold the right mouse and paint the area to zoom by dragging a box to the end concentration Figure 4 17 The area that will be zoomed will be painted 4 69 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 E Post processor Tampa Bay BEES E File Edt View XY Plot Window Help 218 x ey DO mg l Eyga TY aaa eee 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 Year 1989 RAL Ee kee em a CAPS NUM OVA d stan A S X Pant Shop Pio Imaget5_ Fi Post processor ITa Bl amp 226PM Figure 4 17 Zooming the y Axis Upon releasing the right mouse button after the user has defined the area to zoom the x y plot will be redrawn for the given y concentration range Figure 4 18 illustrates a zoomed y axis from the example given above If the user has defined more than one y axis the zooming function becomes a little trickier to perform If the zooming function on the speed menu is set to Auto Detect the default the Graphical Post Processor will determine which axes x y or y the user is trying to zoom based upon the position of the mouse at the time the left mouse button 1s
303. sfer at Water Surfaces Brutsaert W and G H Jirka Eds D Reidel Boston Menon A S W A Gloschenko and N M Burns 1972 Bacteria Phytoplankton Relationships in Lake Erie Proc 15th Conf Great Lakes Res 1972 94 101 Inter Assoc Great Lakes Res Mill T W R Mabey P C Bomberger T W Chou D G Herdry and J H Smith 1982 Laboratory Protocols for Evaluating the Fate of Organic Chemicals in Air and Water US Environmental Protection Agency Athens GA EPA 600 3 82 0220 Mills W B D B Porcella M J Ungs S A Gherini K V Summers Lingfung Mok G L Rupp G L Bowie and D A Haith 1985 Water Quality Assessment A Screening Procedure for Toxic and Conventional Pollutants Parts 1 and 2 U S Environmental Protection Agency Athens GA EPA 600 6 85 002a and b Nriagu JO 1972 Stability of Vivianite and Ion Pair Formation in the System Fe3 PO4 5 H3PO4H50 Geochim Cosmochim Acta 36 p 459 O Connor D J and R V Thomann 1972 Water Quality Models Chemical Physical and Biological Constituents In Estuarine Modeling An Assessment EPA Water Pollution Control Research Series 16070 DZV Section 702 71 pp 102 169 O Connor D J J A Mueller and K J Farley 1983 Distribution of Kepone in the James River Estuary Journal of the Environmental Engineering Division ASCE 109 EE2 396 413 O Connor DJ 1983 Wind Effects on Gas Liquid Transfer Coefficients Journal of Environmental Engineering Volume 1
304. shaded wired frame and violation criteria shading These various modes allows the spatial graphical analysis mode to illustrate information from model simulations in such a manner to make easier for the non technical person to understand the results The 4 45 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 following section provides information on how to use and configure the spatial graphical option To initiate a spatial grid the user should press the spatial grid analysis icon this will generate a spatial grid window as illustrated in Figure 4 2 The user can create as many of these windows as desired Each window can be configured to show different model results as well as different modes FA Post processor EXAMPLE BMD EXAMPLE BMG Segment Depth m at 1 1 1985 0 00 Slice 1 BE Es i File Edit View Spatial Window Help 81 xl 4mm m 7 777 CAPS NUM VA Mstart E A Y Paint Shop Fro Images Ez Post processor IEX EEE Figure 4 2 Spatial Analysis View 4 3 2 Spatial Grid Toolbar The second option for the spatial analysis tool is to allow the user to develop the model network using ArcView and combine the model network with other GIS coverage s To use this method the user must have a copy of ArcView and good working knowledge of how to use it Each spatial grid that is generated by the user has its own set of controls that allow the user to manipulate
305. sorbed and biosorbed concentrations are uniquely determined Equation 11 29 C v C e f 5 Equation 11 30 C SU C e f Equation 11 31 C B C f B These five concentrations have units of mg L and can be expressed as concentrations within each phase Equation 11 32 Gye C w n Equation 11 33 CUm CIHCM Equation 11 34 C57C s B These concentrations have units of mg L mg kg and mg kgg respectively In some cases such as near discharges the user may have to alter input partition coefficients to describe the effect of incomplete sorption As guidance Karickhoff and Morris 1985 found that typical sorption reaction times are related to the partition coefficient Equation 11 35 k 10 03 p 11 14 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 where kg is the desorption rate constant hr Thus compounds with high medium and low Koy s of 10 10 and 10 sorbing onto 2 organic sediment should have reaction times of a day a half hour and seconds Given that time to equilibrium is roughly three times the reaction time the three compounds should reach equilibrium within 3 days 1 hour and 30 minutes 11 5 2 Computation of Partition Coefficients Values for the partition coefficients can be obtained from laboratory experiments For organic chemicals lab studies have shown that the partition coefficient is related to the hydrophobicity of the chemical and the organic matter content of t
306. st be specified in order to solve the sediment balance equations in TOXI Input parameters are prepared for WASP6 in four major sections of the preprocessor environment transport boundaries and transformation Basic model parameters are described in Chapter 6 and will not be repeated here 7 2 2 Environment Parameters These parameters define the basic model identity including the segmentation and control the simulation Systems To simulate total solids only select simulate for Solids 1 and bypass for the other five systems To simulate two solids types select simulate for both Solids 1 and Solids 2 To simulate three solids types select simulate for all three The chemical systems can be simulated or bypassed Figure 3 7 Bed Volume Option The user must determine whether bed volumes are to be held constant or allowed to vary Volumes may be held constant by specifying 0 in which case sediment concentrations and porosities in the bed segments will vary Alternatively sediment concentrations and porosities may be held constant by specifying 1 in which case surficial bed segment volumes will vary Figure 3 6 Bed Time Step While mass transport calculations are repeated every model time step certain benthic calculations are repeated only at this benthic time step in days If the constant bed volume option is chosen sediment concentrations are updated every model time step but 7 9 DRAFT Water Quality Analysis S
307. stant must have units of day The temperature may be time variable as well input as a time series Input data are described below VARIABLE TREFE 1173 1773 KE20n 1176 1776 KE 2021 1181 1781 KE203 1186 1786 1191 1791 Extra Reaction Rate L mole day The user may specify second order extra rate constants for each phase dissolved DOC sorbed and sediment sorbed and each ionic specie using constant KE20 Constant numbers for the neutral molecule are summarized in Table 7 21 KE20 refers to the dissolved neutral chemical KE205 refers to the DOC sorbed neutral chemical KE203 refers to the sediment sorbed neutral chemical Activation Energy kcal mole K The user may specify activation energies for each chemical using constant EEX Constant numbers are summarized in Table 7 21 If EEX is omitted or set to 0 oxidation rates will not be affected by temperature Reference Temperature C The user may specify the reference temperature at which oxidation rates were measured using constant TREFE Constant numbers are summarized in Table 7 21 If a reference temperature is not supplied then a default of 20 C is assumed Extra Environmental Concentration mole L The user should specify segment variable extra environmental concentrations using parameter 15 EXENV Group G Record 4 PARAM LI5 11 51 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 12 REFERENCES Alexander M 1980 Biodegradati
308. stant with Z t omitted default value 1 Reported grazing rates vary from 0 1 to 1 5 L mgC day Bowie et al 1985 9 13 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 9 1 7 Phytoplankton Settling The settling of phytoplankton is an important contribution to the overall mortality of the phytoplankton population particularly in lakes and coastal oceanic waters Published values of the settling velocity of phytoplankton mostly under quiescent laboratory conditions range from 0 07 18 m day In some instances however the settling velocity is zero or negative Actual settling in natural waters is a complex phenomenon affected by vertical turbulence density gradients and the physiological state of the different species of phytoplankton Although the effective settling rate of phytoplankton is greatly reduced in a relatively shallow well mixed river or estuary due to vertical turbulence it still can contribute to the overall mortality of the algal population In addition the settling phytoplankton can be a significant source of nutrients to the sediments and can play an important role in the sediment oxygen demand In EUTRO phytoplankton are equated to solid type 2 Time and segment variable phytoplankton settling velocities can be input by the user then using transport field 4 so that Equation 9 15 k 47 V s4ij 54 D where ky the effective phytoplankton settling or loss rate day Vaj7 the n settling
309. sure Analysis Modeling System EXAMS Burns et al 1982 Burns and Cline 1985 Each organic chemical may exist as a neutral compound and up to four ionic species The neutral and ionic species can exist in five phases dissolved sorbed to dissolved organic carbon DOC and sorbed to each of the up to three types of solids 8 Local equilibrium is assumed so that the distribution of the chemical between each of the species and phases is defined by distribution or partition coefficients In this fashion the concentration of any specie in any phase can be calculated from the total chemical concentration Therefore only a single state variable WASP system representing total concentration is required for each chemical The model then is composed of up to six systems three chemicals and three solids for which the general WASP6 mass balance equation is solved There are often other factors that may influence the transport and transformations of the chemicals simulated For example water temperature affects reaction kinetics sorption may also occur onto dissolved organic carbon and pH can affect ionization and hydrolysis reactions These concentrations or properties are included in TOXI through the use of model parameters and time functions They are specified to the model described rather than simulated They may be varied over space e g between model segments and or over time Examples of the concentrations or properties that are descr
310. t only initial concentrations but also the density and solids transport field for each solid and the dissolved fraction in each segment Boun Concentrations _mg L Steady or time variable concentrations must be specified for each water quality constituent at each boundary A boundary is a tributary inflow a downstream outflow or an open water end of the model network across which dispersive mixing can occur Advective and dispersive flows across boundaries are specified by the transport parameters Values are entered as a time function series of concentrations and time in days Figure 3 15 Waste Loads kg day Steady or time variable loads may be specified for each water quality constituent at several segments These loads represent municipal and industrial wastewater discharges urban and agricultural runoff precipitation and atmospheric deposition of pollutants Values are entered as a time function series of loads and time in days Figure 3 16 Initial Concentrations mg L Concentrations of each constituent in each segment must be specified for the time at which the simulation begins For those water bodies with low transport rates the initial concentrations of conservative substances may persist for a long period of time Accurate simulation then would require accurate specification of initial concentrations If initial concentrations cannot be determined accurately then longer simulations should be run and early predictions disc
311. taken up by phytoplankton for growth and incorporated into phytoplankton biomass The rate at which each is taken up is a function of its concentration relative to the total inorganic nitrogen ammonia plus nitrate available Nitrogen is returned from the phytoplankton biomass pool to dissolved and particulate organic nitrogen and to ammonia through endogenous respiration and nonpredatory mortality Organic nitrogen is converted to ammonia at a temperature dependent mineralization rate and ammonia is then converted to nitrate at a temperature and oxygen dependent nitrification rate Nitrate may be converted to nitrogen gas in the absence of oxygen at a temperature and oxygen dependent denitrification rate 9 1 3 Dissolved Oxygen Dissolved oxygen is coupled to the other state variables The sources of oxygen considered are reaeration and evolution by phytoplankton during growth The sinks of oxygen are algal respiration oxidation of detrital carbon and carbonaceous material from waste effluents and nonpoint discharges and nitrification These processes are discussed in Chapter 8 9 1 4 Phytoplankton Kinetics Phytoplankton kinetics assumes a central role in eutrophication affecting all other systems An overview of this system is given in 9 3 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 PHYTOPLANKTON KINETICS O C N P ac _ Rg Rg Rg Cg C p Phytoplankton concentration mL 3 Rg growth rate T
312. tant or time variable If ionization is specified in input separate transformation and reaction rates may be specified for each ionic specie For example where necessary different sorption biodegradation hydrolysis oxidation and photolysis constants may be specified for each ionic specie providing considerable flexibility in the model r ob SPECIE E pu ob i Po varase 0 NS 85 997 os 91 691 1291 Negative Log of Ionization Constant PKAi 1292 1293 EL 1295 Ionization Reaction Enthalpy EPK Ai kcal mole i 1296 it Fa Fi ES a Ue 0 C 11 10 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 The transformation input parameters for ionization are summarized below Constant numbers are given in Table 7 5 Ionization Switches The user may choose to simulate ionic species by specifying values of 1 0 for constant SFLG Ionization Constants For each ionic specie being simulated the user should provide a value for the negative log of the frequency factor in the Van t Hoff equation using constant PKA If the activation energy is 0 then this is equivalent to the pK or pK Reaction Enthalpy kcal mole To simulate temperature dependence for ionization the user can specify the standard enthalpy change of the dissociation reaction using constant EPKA Higher reaction enthalpies cause more temperature dependence pH The user may specify segm
313. te x y Plot This option is available when there is more than one line on the graph It will toggle the display one line on the graph at time for visual inspection It is used to declutter the graph to see differences 4 56 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Configure x y Plot This icon is used to configure what data is used and how it is displayed in the x y plot p ES Un Zoom One Level This option will un zoom the graph one user performed zoom level at a time It undoes a zoom one step at a time Un Zoom x y Plot This icon will un zoom the graph to its original axes dimension at the time of creation of the graph Print x y Plot to Printer This option allows the user to print the x y plot to a printer A normal Windows printer dialog box will appear to allow the user to control the appearance of the graph Copy Graphic Image to Clipboard This option makes a copy of the x y plot onto the Windows clipboard This clipboard image can then be pasted into programs like a word processor for publication E oe Save Graph to Disk This option creates a Windows bitmap file BMP of the x y graph window The saved BMP can be imported into programs like a word processor for publication gt Export Graph to ASCH Table This option creates an ASCII file containing the values for each of the lines from the graph window This table can be imported into a spreadsheet or other programs Curve
314. ter Quality Analysis Simulation Program WASP Version 6 0 PORT AND WOM POINT AJTOCHTHONOUS SOURCES SOURCE INPUTS DEAD WV ERTEBRATES FECAL PELLETS ALGAL ExUDATES CARBONACEOUS BOD ORS0OLVED ANO A ee a pure MICRORIA WATER COLUMN ADSORPTION ABSORPTION fr SENTMC mota Sources and Sinks of Carbonaceous BOD in the Aquatic Environment Figure 8 3 BOD Sources in the Aquatic Environment The oxidation of carbonaceous material is the classical BOD reaction Internally the model uses ultimate carbonaceous biochemical oxygen demand CBOD as the indicator of equivalent oxygen demand for the carbonaceous material A principal source of CBOD other than man made sources and natural runoff is detrital phytoplankton carbon produced as a result of algal death The primary loss mechanism associated with CBOD is oxidation Equation 8 9 C H 0 CO H O The kinetic expression for carbonaceous oxidation in EUTRO contains three terms a first order rate constant a temperature correction term and a low DO correction term The first two terms are standard The third term represents the decline of the aerobic oxidation rate as DO levels approach 0 The user may specify the half saturation constant Kpop which represents the DO level at which the oxidation rate is reduced by half The default value is zero which allows this reaction to proceed fully even under anaerobic conditions Direct comparisons between observed BOD data and model out
315. ter column segments should be defined in the standard fashion If settling is to be simulated i e for ON OP PHYT PO4 or CBOD the user should add a single benthic segment underlying all water column segments This benthic segment will merely act as a convenient sink for settling organic matter Model calculations within this benthic segment should be ignored 9 7 2 Transport Parameters This group of parameters defines the advective and dispersive transport of model variables Number of Flow Fields To simulate settling of ON OP and CBOD the user should select solids 1 flow under advection To simulate settling of PHYT the user should select solids 2 flow To simulate PO4 settling the user should select solids 3 flow The user should also select water column flow Particulate Transport m sec Time variable settling and resuspension velocities can be specified for particulate ON OP CBOD PHYT and PO4 as described in the simple eutrophication section above 9 7 3 Boundary Parameters This group of parameters includes boundary concentrations waste loads and initial conditions Boundary concentrations must be specified for any segment receiving flow inputs outputs or exchanges Initial conditions include not only initial concentrations but also the density and solids transport field for each solid and the dissolved fraction in each segment Boundary Concentrations mg L At each segment boundary time variable concentr
316. terval is used The user must provide at least two pairs of data 3 31 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 le x Print Interval i ae A EE m EB o a mns 1200AM 3000 4 8 30 1985 12 00 AM 16 00 Pisae ine cs e 10 13 1906 1200AM 1700 7 zane aman rem a 2nense 1200AM 30 mo 7798 1200AM 1700 w ise M 39 12 sense 1200AM 1600 ma sasise 1200AM 300 M i Figure 3 19 WASP6 Print Interval Definitions 3 17 Time Functions The time function data entry forms allow the user to enter time variable environmental information WASP6 offers a selection of all the environmental time functions for a given model type 3 32 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 AScl WIN AWASP Standard C winwasp Example T ampa WIF Tampa Input Data Set EUTRO File Project Pre processor Model Post Processor Help Water Temperature Function 1 c Water Temperature Function 2 c Water Temperature Function 4 c Daily Solar Radiation Lanaleys Fraction Daily Light fraction qx x71 TE ERRAT Time Value 12 00 AM 16 50 2 1 31 1985 12 00 AM 17 10 3 3 2 1985 12 00AM 19 40 4 4 1 1985 12004M 19 60 Heu e i 9 y Pi Insert
317. th the solids or an assimilation depuration process with the phytoplankton If the total suspended solids are considered the particulate concentration can be defined as Equation 9 16 C pip C pip M where Co concentration of phosphorus sorbed to solids mg P kg M M concentration of solids kg L The total inorganic phosphorus is then the sum of dissolved inorganic and the particulate inorganic phosphorus Equation 9 17 C3 C prp t C pip The underlying assumption that is made as mentioned previously is instantaneous equilibrium between the adsorption desorption processes The equilibrium between the dissolved inorganic phosphorus in the water column and the mass concentration of inorganic phosphorus of the solids is usually expressed in terms of a partition coefficient Equation 9 18 C pip K pip DIP where K pp partition coefficient for particulate phosphorus mg P kg M per mg P L or L kg M Substituting Equation 9 18 into Equation 8 16 gives 9 19 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Equation 9 19 C p K pip M C pip Equation 5 19 is the linear portion of the Langmuir isotherm Although not always representative of actual conditions it is a reasonable approximation when the sorbed phosphorus concentration is much less than the ultimate adsorbing capacity of the solids Combining Equations 5 17 and 5 19 the total concentration may be expressed as Equation 9
318. their concentrations explicitly would of necessity be speculative Thus one uses a simplified yet realistic formulation of these reactions The method proposed by Di Toro and Connolly 1980 and highlighted here is based upon separating the initial reactions that convert sedimentary organic material into reactive intermediates and the remaining redox reactions that occur Then using a transformation variable and an orthogonality relationship Di Toro and Connolly derive mass balance equations that are independent of the details of the redox equations Rather they are only functions of the component concentration and it suffices to compute only the component concentrations which can be treated in exactly the same way as any other variable in the mass transport calculation The convenient choices of components for the calculation are those that parallel the aqueous variables carbonaceous BOD and dissolved oxygen Restricting the calculation to these components however eliminates the possibility of explicitly including the effects of other reduced species such as iron manganese and sulfide which play a role in overall redox reactions and may be involved in the generation of sediment oxygen demand This simplification appears reasonable in light of the preliminary nature of the benthic calculation The decomposition reactions that drive the component mass balance equations are the anaerobic decomposition of the algal carbon and the anaerobic
319. tics based upon the range of the data For the most part these heuristics provide very meaningful graphs However the user has the ability to set the range of the x axis manually To manually 4 62 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 control the range of x axis the user should select the restrict x axis range from the graph configuration window Once this is selected the user may enter values for the minimum and maximum values for the x axis Note There are more sophisticated methods for manipulating the range of the x axis see Zooming X Axis Restrict y y Range By default the y axis is automatically scaled using built in heuristics For the most part these heuristics provide very meaningful graphs However the user has the ability to set the scale of the yaxis manually To enter a value for the y scale the user should select to restrict y axis range from the graph configuration window Once this is selected the user may enter values for the minimum and maximum values for the y axis being defined Note The user can control the range for both the Y and Y axes Graph Title This dialog box is used to describe the title that will be displayed at the top of the graph The user is limited to 25 characters within the title line Animation Delay The animation delay dialog box allows the user to define the delay when the user presses the animation button from the x y toolbar Color Bl
320. tion used for the derivatives If the advection factor 6 0 the backward difference approximation of dc dx is used in the advection term and Equation 6 18 UL Linc where L length of the segment m For the Euler scheme the forward difference approximation of dc dt is used and Equation 6 19 U At 2 E num The total numerical dispersion then is Equation 6 20 E num L U At 6 16 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Note that increasing the time step up to Ax U or V Q decreases numerical dispersion to 0 The conditions for stability discussed above require a time step somewhat less than V Q for most segments So to maintain stability and minimize numerical dispersion in a water body subject to unsteady flow the sequence of time steps must be as large as possible but always less than Atnax given in Equation 6 17 Figure 3 18 Print Intervals days The user must specify the print intervals controlling the output density in the print file transferred to the post processor The model will store all display variables in all segments after each print interval throughout the simulation Different print intervals can be specified for different phases in the simulation At least two print intervals must be specified one for time 0 and one for the final time Figure 3 19 Segment Volumes m Initial volumes for each segment must be specified These can be calculated from navig
321. tion is desorption These reactions are usually fast in comparison with the model time step and can be considered in local equilibrium The phase concentrations Cy Cs and Cg are governed by the equilibrium partition coefficients Kpso and KpB L kg Equation 11 21 C n M s C C K ps0 ESAE Gy Equation 11 22 Csh Cs DuC OE K p 11 12 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 These equations give the linear form of the Freundlich isotherm applicable when sorption sites on sediment and DOC are plentiful Equation 11 23 C K ps C Equation 11 24 C s K pB C The total chemical concentration is the sum of the five phase concentrations Equation 11 25 C2C n C M C3SB Substituting in equations 7 24 and 7 25 factoring and rearranging terms gives the dissolved fraction fp Equation 11 26 Cyn _ n C ntK B K ps Ms f p Similarly the sediment sorbed and DOC sorbed fractions are Equation 11 27 C M K p Ms f aS O C n K B K p Ms Equation 11 28 yu CE K p B C OntKy B K p Ms 11 13 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 These fractions are determined in time and space throughout a simulation from the partition coefficients internally calculated porosities simulated sediment concentrations and specified DOC concentrations Given the total concentration and the five phase fractions the dissolved
322. tling scour and sedimentation rates is usually necessary 7 1 Overview of WASP Sediment Transport Sediment size fractions or solids types are simulated using the TOXI program Simulations may incorporate total solids as a single variable or alternately represent from one to three solids types or fractions The character of the three solids types is user defined They may represent sand silt and clay or organic solids and inorganic solids The user defines each solid type by specifying its settling and erosion rates and its organic content WASP6 performs a simple mass balance on each solid variable in each compartment based upon specified water column advection and dispersion rates along with special settling deposition erosion burial and bed load rates Mass balance computations are performed in benthic compartments as well as water column compartments Bulk densities or benthic volumes are adjusted throughout the simulation The user can vary all solids transport rates in space and time There are however no special process descriptions for solids transport Erosion rates for example are not programmed as a function of sediment shear strength and water column shear stress Consequently the TOXI sediment model should be considered descriptive and must be calibrated to site data 7 1 1 Sediment Transport Processes Water Column Transport 7 1 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Sedi
323. toplankton the nitrifying bacterial populations are sensitive to flow During periods of high flow or storm runoff upstream bacteria may be advected downstream with some lag time after a flow transient before they can build up to significant levels again The process of nitrification in natural waters then is complex depending on dissolved oxygen pH and flow conditions which in turn leads to spatially and temporally varying rates of nitrification To properly account for this complex phenomenon in the modeling framework would be difficult and would require a database that is usually unavailable The kinetic expression for nitrification in EUTRO contains three terms a first order rate constant a temperature correction term and a low DO correction term The first two terms are standard The third term represents the decline of the nitrification rate as DO levels approach 0 The user may specify the half saturation constant Kwrr which represents the DO level at which 9 25 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 the nitrification rate is reduced by half The default value is zero which allows this reaction to proceed fully even under anaerobic conditions 9 3 6 Denitrification Denitrification refers to the eduction of NO or NO2 to N and other gaseous products such as N5O and NO This process is carried out by a large number of heterotrophic facultative anaerobes Under normal aerobic conditions foun
324. tzel 1975 Enumeration techniques unclear 11 48 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 PParis et al 1981 Bacterial enumeration using plate counts Herbes amp Schwall 1978 Bacterial enumeration using plate counts Larson et al 1981 Bacterial enumeration using plate counts The user may enter time variable water column and benthic bacterial concentrations via time funcions BACNW and BACNS respectively as a series of concentration versus time values Parameter BAC will then represent the ratio of each segment concentration to the time function values The product of BAC and the BACNW or BACNS function gives the segment and ime specific bacterial concentrations used by TOXI Group G Record 4 PARAM I 14 Group I Record 2 VALT 16 K VALT 17 K 11 11 Extra Reaction An extra second order reaction is included in TOXI The second order reaction allows the user to simulate the effect of processes not considered by TOXI The reaction depends upon a rate constant and a environmental parameter which may be taken to represent for example some reducing or oxidizing agent The rate of reaction may also vary with temperature 11 11 1 Overview of TOXI Extra Reaction TOXI allows the user to specify an additional second order reaction for the various species and phases of each chemical Equation 11 73 Kee IEEIY Y kafa where K net extra reaction rate constant day E intensity of envir
325. ure dependent light saturation parameter is an unknown in the Di Toro light formulation and must be determined via the calibration verification process In the Smith formulation this term is calculated from parameters that are reasonably well documented in the literature As Smith 1980 points out since the early experiments of Warburg and Negelein 1923 maximum photosynthetic quantum yield Omax has been measured for a wide range of conditions reviewed by Kok 1960 and a nearly temperature independent value of 0 08 to 0 1 mole O2 per mole of photons absorbed is now widely accepted for photosynthesizing plants in general in the laboratory Bannister 1974a gives good arguments for adopting 0 06 mole carbon 0 07 mole Oz per mole of photons as the maximum yield for plankton in nature Reported values for K generally fall in the range 0 01 to 0 02 m mg and 0 016 n mg has been suggested as the approximate average Bannister 1974b A second feature incorporated in the modeling framework derived from Smith s work is the calculation of a variable carbon to chlorophyll ratio based on the assumption that adaptive changes in carbon to chlorophyll occur so as to maximize the specific growth rate for ambient conditions of light and temperature Smith found that phytoplankton adjusts chlorophyll composition so that roughly equals 30 of the average available light The expression used to calculate the carbon to chlorophyll ratio is presented in E
326. values for LGHTS and IS1 are 1 and 300 respectively Respiration Rate day The average phytoplankton respiration rate constant and temperature coefficient can be input using constants KIRC and KIRT respectively Death Rate day The non predatory phytoplankton death rate constant can be input using constant K1D No temperature dependence is assumed Phosphorus to Carbon Ratio mg P mg C The average phosphorus to carbon weight ratio in phytoplankton can be specified using constant PCRB The EUTRO default value for PCRB is 0 025 Phosphorus Mineralization Rate day The mineralization rate constant and temperature coefficient for dissolved organic phosphorus can be specified using constants K83C and K83T respectively Phosphorus Half Saturation Constant mg P L The phosphorus half saturation constant for phytoplankton growth can be specified using constant KMPG1 When inorganic phosphorus concentrations are at this level the phytoplankton growth rate is reduced by half 9 37 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Nitrogen to Carbon Ratio mg N mg C The average nitrogen to carbon weight ratio in phytoplankton can be specified using constant NCRB The EUTRO default value for NCRB is 0 25 Nitrogen Mineralization Rate day The mineralization rate constant and temperature coefficient for dissolved organic nitrogen can be specified using constants K71C and KT7IT respectively Nitrificatio
327. varied between model segments If a lumped decay rate constant is specified the chemical will react at that rate regardless of other model input 10 3 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 10 1 2 Option 2 Individual First Order Transformation This option allows the user to input a global first order reaction rate constant separately br each of the following processes volatilization water column biodegradation benthic biodegradation alkaline hydrolysis neutral hydrolysis acid hydrolysis oxidation photolysis and an extra reaction The total reaction is then based on the sum d each of the individual reactions as given by Equation 10 2 9C 3 i lacno Y K ki C ij ot e where Ky first order transformation constants for reaction k of chemical i day The user may input half lives rather than first order decay rate constants If half lives are provided for the transformation reactions they will be converted internally to first order rate constants and used as above Equation 10 3 K u 9 693 T ini where Tas half life of reaction k for chemical i days 10 2 Equilibrium Sorption Sorption is the bonding of dissolved chemicals onto solid phases such as benthic and suspended sediment biological material and sometime dissolved or colloidal organic material Sorption can be important in controlling both the environmental fate and the toxicity of chemicals Sorption may cause the
328. velocity of phytoplankton from segment j to segment i m day D depth of segment j equal to volume surface area m 9 1 8 Summary This completes the specification of the growth and death rates of the phytoplankton population in terms of the physical variables light temperature and the nutrient concentrations present Table 9 2 summarizes the variables and parameters in the net growth equations With these variables known as a function of time it is possible to calculate the phytoplankton chlorophyll throughout the year Table 9 2 Phytoplankton net growth terms Exogenous Variables Description Notation Values Units Extinction Coefficient Ke 0 1 5 m Segment D epth D 0 1 30 m Water Temperature T 0 35 oC Fraction of day that is daylight f 0 3 0 7 Average D aily Surface Solar Radiation Ia 200 750 langleys day 9 14 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Exogenous Variables Description Notation Values Units Zooplankton Population Z 0 mgC L Rate Constants Description Notation Values Units Maximum G rowth Rate kic 2 0 day Temperature Coefficient Eic 1 068 none Maximum Photosynthetic Quantum Y ield O max 720 0 mg C mole photon Phytoplankton Self Light Attenuation Ke 0 017 m mg Chl a Carbon Chlorophyll Ratio Ec 20 50 Saturating Light Intensity Is 200 500 langleys day Half Saturation Constant for Nitrogen Km 25 0 ng N L Half Saturation Constant for Phosphorus Kmp 1 0 ng P L Endogenous Res
329. verview of WASP6 Tracer Transport gt Z 6 1 6 20 Transport Processes 00 0 0 00 00 LLL 6 1 6 2 1 Hydrodynamic Linkage 6 2 6 2 2 Hydraulic Geometry 6 4 6 2 3 Pore Water Advection 6 7 6 2 4 Water Column Dispersion 6 7 6 2 5 Pore Water Diffusion 6 8 6 2 6 Boundary Processes 6 9 6 2 7 Loading Processes 6 10 62 8 Nonpoint Source Linkage 6 11 6 29 Initial Conditions 6 12 6 3 ModelImplementation_ 6 13 6 4 Model Input Parameters _________ 0 6 13 6 4 1 Environment Parameters 6 13 6 42 Transport Parameters 6 17 6 4 3 Boundary Parameters 6 18 6 4 4 Transformation Parameters 6 19 6 4 5 External Input Files 6 19 7 Sediment Transport 7 1 7 1 Overview of WASP Sediment Transport i s CsCS 7 1 7 1 1 Sediment Transport Processes 7 1 7 1 2 Sediment Loading 7 4 7 1 3 The Sediment Bed 7 5 7 23 Model Implementation 7 9 7 2 1 Model Input Parameters 7 9 7 2 23 Environment Parameters 7 9 7 2 3 Boundary Parameters 7 10 7 24 Transformation Parameters 7 1 6 Dissolved Oxygen 8 1 8 1 Overview of WASP6 Dissolved Oxygen Ci MCC 8 1 8 2 Dissolved Oxygen Processes 1 8 3 8 2 1 Reaeration 8 4 8 22 Carbonaceous Oxidation 8 7 8 23 Nitrification 8 9 8 24 Denitrification 8 10 8 25 Settling 8 10 8 26 Phytoplankton Growth 8 10 8 2 7 Phytoplankton Death 8 11 8 28 Sediment Oxygen Demand 8 11 8 8 ModelImplementation_ 8 14 8
330. ving force for the water layer diffusion Pressure differences drive the diffusion for the air layer From mass balance considerations it is obvious that the same mass must pass through both films thus the two resistances combine in series so that the conductivity is the reciprocal of the total resistance Equation 11 41 M ais H K Ri Ro Kil Ke RTk liquid phase resistance day m liquid phase transfer coefficient m day 11 20 where DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Rg Kc There is actually yet another resistance involved the transport resistance between the two interfaces but it is assumed to be negligible This may not be true in two cases very turbulent conditions and in the presence of surface active contaminants Although this two resistance method the Whitman model is rather simplified in its assumption of uniform layers it has been shown to be as accurate as more complex models gas phase resistance day m gas phase transfer coefficient m day The value of Ky the conductivity depends on the intensity of turbulence in a water body and in the overlying atmosphere Mackay and Leinonen 1975 have discussed conditions under which the value of Ky is primarily determined by the intensity of turbulence in the water As the Henrys Law coefficient increases the conductivity tends to be increasingly influenced by the intensity of turbulence in water As the Henry s Law coef
331. which the simulation begins If the variable benthic volume option is used the benthic sediment concentrations specified here will remain constant for the entire simulation Figure 3 10 Dissolved Fraction The dissolved fraction of each solid in each segment should be set to 0 Figure 3 11 7 2 4 Transformation Parameters This group of parameters includes spatially variable parameters constants and kinetic time functions for the water quality constituents being simulated None are necessary for sediment transport DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 8 Dissolved Oxygen Dissolved oxygen DO is one of the most important variables in water quality analysis Low concentrations directly affect fish and alter a healthy ecological balance Because DO is affected by many other water quality parameters it is a sensitive indicator of the health of the aquatic system DO have been modeled for over 70 years The basic steady state equations were developed and used by Streeter and Phelps 1925 Subsequent development and applications have added terms to their basic equation and provided for time variable analysis The equations implemented here are fairly standard As explained below the user may implement some or all of the processes that are described with terms in these equations 8 1 Overview of WASP6 Dissolved Oxygen Dissolved oxygen and associated variables are simulated using the EUTRO program Seve
332. winwasp E xample T ampa DB C winwasp E xample T ampa WIF C winwasp E xample roads shp A lesay IE Y AScl WINAWASP Figure 3 5 Project File Definition 3 7 Input Parameterization When creating a new input dataset the input parameterization data entry form is the first one that needs to be completed This form provides basic information that is needed by the program to parameterize the other data entry forms that follow This screen informs the program what type of WASP6 file you are going to be creating DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 le x Example input data set for Tampa Bay FL for the period of 1985 1994 This is an example only and should not be used for any other purpose 1 1 1985 111 94 Figure 3 6 Dataset Parameterization 3 7 1 Data Set Description This field provides a one line descriptor for the defined input data file This descriptor is displayed on the caption line of the main WASP6 window 3 7 2 Model Type The model type dialog box allows the user to specify which WASP6 model type EUTRO TOXT the input dataset is being created Setting the model type parameterizes WASP6 for that particular model type Note that if you define a model as one type and change types later all model type specific data will be re initialized Time Functions Kinetics Parameters Boundaries Init
333. wn and T A Scott 1979 Sorption of Hydrophobic Pollutants on Natural Sediments Water Res 13 241 248 Karickhoff S W 1984 Organic Pollutant Sorption in Aquatic Systems J Hydraul Eng Div ASCE Vol 110 p 707 Karickhoff S W and K R Morris 1985 Sorption Dynamics of Hydrophobic Pollutants in Sediment Suspensions Environ Toxicology and Chem 4 469 479 Kok B 1960 Efficiency of Photosynthesis In W Ruhland Edison Hanbuch der Pfanzenphysiologie Vol 5 Part 1 Springer Berlin pp 563 633 Larson RJ G G Clinckemaillie and L VanBelle 1981 Effect of Temperature and Dissolved Oxygen on Biodegradation of Nitrilotriacetate Water Research Volume 15 pp 615 620 Leopold L B and T Maddox 1953 The Hydraulic Geometry of Stream Channels and Some Physiographic Implications Professional Paper 252 U S Geological Survey Washington DC Leopold L B M B Wolman and J P Miller 1964 Fluvial Processes in Geomorphology W H Freeman and Co San Francisco CA 12 3 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Lowe W E 1976 Canada Centre for Inland Waters 867 Lakeshore Road Burlington Canada L7R 4A6 Personal communication Mackay D and P J Leinonen 1975 Rate of Evaporation of Low Solubility Contaminants from Water Bodies to Atmospheres Environ Sci Technology 7 611 614 Mackay D and W Y Shiu 1984 Physical Chemical Phenomena and Molecular Properties in Gas Tran
334. xplained in the phosphorus mineralization section This mechanism slows the mineralization rate if the phytoplankton population is small but does not permit the rate to increase continuously as phytoplankton increase The default value for the half saturation constant Kap is 0 which causes mineralization to proceed at its first order rate at all phytoplankton levels 9 3 4 Settling Particulate organic nitrogen settles according to user specified velocities and particulate fractions Particulate organic nitrogen is equated to solid type 1 which represents organic matter Time and segment variable organic matter settling velocities v 3 can be input by the user using transport field 3 Segment variable organic nitrogen dissolved fractions 7 are input with initial conditions 9 3 5 Nitrification Ammonia nitrogen in the presence of nitrifying bacteria and oxygen is converted to nitrate nitrogen nitrification The process of nitrification in natural waters is carried out by aerobic autotrophs Nitrosomonas and Nitrobacter predominate in fresh waters It is a two step process with Nitrosomonas bacteria responsible for the conversion of ammonia to nitrite and Nitrobacter responsible for the conversion of nitrite to nitrate Essential to this reaction process are aerobic conditions Also this process appears to be affected by high or low values of pH that inhibit Nitrosomonas growth particularly for pH below 7 and greater than 9 As with phy
335. y or via organisms that are not capable of utilizing the chemical as a substrate for growth Two general types of biodegradation are recognized growth metabolism and cometabolism Growth metabolism occurs when the organic compound serves as a food source for the bacteria Adaptation times from 2 to 20 days were suggested in Mills et al 1985 Adaptation may not be required for some chemicals or in chronically exposed environments Adaptation times may be lengthy in environments with a low initial density of degraders Mills et al 1985 For cases where biodegradation is limited by the degrader population size adaptation is faster for high initial microbial populations and slower for low initial populations Following adaptation biodegradation proceeds at fast first order rates Cometabolism occurs when the organic compound is not a food source for the bacteria Adaptation is seldom necessary and the transformation rates are slow compared with growth metabolism The growth kinetics of the bacterial population degrading a toxic chemical are not well understood The presence of competing substrates and of other bacteria the toxicity of the chemical to the degrading bacteria and the possibilities of adaptation to the chemical or co metabolism make quantification of changes in the population difficult As a result toxic chemical models assume a constant biological activity rather than modeling the bacteria directly Often measured first order b
336. y plots can either be displayed in black amp white or color depending upon user preference or intentions To toggle between these two modes the user can press the black and white icon from the toolbar toggle the radio box in the configuration menu or use the speed menu An example of a black amp white plot is given in Figure 4 19 When the user requests that a black amp white graph be printed or copied to the clipboard a black amp white image is generated EN Post processor Tampa Bay 8 xi al File Edi View XY Plot Window Help Aa xl EE IA Foal L TES AVIA MN Hf NI LLLI HE ina CoE ATIT E 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 4 4 DAAR Ex NUR Ov d stat E Sy A Y veas WIN AwasP BS Paint Shop Pro Imaget Post processor Ta e B 10034M Figure 4 19 Example of Black amp White Graph 1989 4 4 8 Observed Measured Data Overview The user may plot observed measured data against that predicted by the model Observed data have to be stored in a particular file format to be available for plotting The file formats are Paradox 4 5 or higher database tables Also the Paradox database must contain at least four requisite field names These field names are used to align the data from the database to the dialog boxes of the x y plot curve parameters 4 72 DRAFT Water Quality Analysis Simulation Program WASP Version 6 0 Creating a D

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