i-Tree Hydro User Manual
Contents
1. Density H Distance E Extraction Gy Generalization a amp Groundwater 76 Hydrology Basin Fill Flow Accumulation Flow Direction Flow Length ag Layers E ned_77764315 Value High 422 531 i 167 455 Snap Pour Point Stream Link Stream Order Stream to Feature FOr i bE a BEREE O 81 616 41 756 Decimal Degrees 3 First choose the option to fill the DEM model using the Fill tool 4 Next compute flow direction on the filled DEM layer from step 3 using the Flow Direction tool 5 Next compute flow accumulation on the flow direction layer from step 4 using the Flow Accumulation tool 6 Create a pour point for the watershed based on the location of your stream gauge station GoToXY Degrees Minutes Seconds Xi a Under the ArcGIS e 8 Y Edit menu select om the Go To XY Long 81 3748 W Lat 41 2343 N tool 23 Enter the degrees minutes and seconds of your stream gauge station in the following format Long 81 37 48 W Lat 41 23 A43 N Use a space in place of the degree symbol use single quotes for minutes double quotes for seconds and direction letters rather than negative signs c Select the Add Point button to place a marker on the stream gauge location watershed pour point d Because of the mechanics of creating a DEM it is unlikely that your stream gauge marker will line up exactly with the stream created by the DE2. No TS data available in NPDES dataset pooled includes NURP USGS For Hydro the pooled median and mean EMC value for each pollutant Table 3 were applied to the runoff regenerated from pervious and impervious surface flow not the base flow values to estimate effects on pollutant load across the entire modeling time frame All rain events are treated equally using the EMC value which means some events may be overestimated and others underestimated In addition local management actions e g street sweeping can affect these values However across the entire season if the EMC value is representative of the watershed the estimate of cumulative effects on water quality should be relatively accurate Accuracy of pollution estimates will be increased by using locally derived coefficients It is not known how well the national EMC values represent local conditions References Beaulac M N and Reckhow K H 1982 An examination of land use nutrient export relationships Water Resources Bulletin 18 6 1013 1024 Charbeneau RJ Barretti M 1998 Evaluation of methods for estimating stormwater pollutant loads Water Environ Res 70 1295 1302 Driver N E Mustard M H Rhinesmith R B and Middelburg R F 1985 U S Geological Survey urban stormwater data base for 22 metropolitan areas throughout the United States United States Geological Survey Open File Report 85 337 Lakewood CO Sansalone J J Buchberger S G 1997 P
3. Source Default value Local value Cover Beneath Trees should total 100 Shrub cover beneath trees Eco 12 3 Herbaceous cover beneath trees Eco 73 4 Soil cover beneath trees Eco 8 2 Impervious cover beneath trees Eco 6 1 Percentage of impervious cover where drainage is directly GIS 65 connected to the stream via a pipe network Other optional fields in Advanced Settings Leaf transition period days number of days to convert from iterature 28 completely leaf off to full leaf area index or vice versa Specific leaf storage mm depth eret 0 2 of water captured on leaf surfaces Tree bark area index Literature 1 7 Shrub bark area index Literature 0 5 Leaf on day day of year 1 365 Defaults are average day of year that trees i Literature regionally come into leaf date is the mid point M of the leaf transition period P Leaf off day day of year 1 365 Defuse are average day of year that trees have itetature rename lost their leaves date is the mid a y point of the leaf transition period P Coefficient for effective precipitation iterare 1 amp 10 a DEM DEM data see Appendix 1 ECO An existing i Tree Eco study although it is unlikely that the Eco study area and the Hydro study area will align exactly your Eco results might offer some insight Canopy i Tree Canopy UTC An existing urban tree canopy analysis G S Your local government or university G
4. NOTE This process takes about 10 minutes Your anti virus software may show a warning regarding the file pest exe Allow that file to run 2 Once the auto calibration is complete click Check Calibration In the Parameter Calibration Results window that appears the values for flow for the initial parameters are compared with those for the auto calibrated parameters With a very good fit values will approach 1 0 but this often does not happen due to mismatches in the precipitation and flow data described above Typically values are 0 3 to 0 7 but higher is better NOTE If calibration results are poor you may need to find precipitation data that more closely matches the conditions in the watershed 3 If you are not satisfied with the fit of the model you can adjust some parameters to see the effects on the model a Begin by clicking Save As New Parameter Set and enter a name for the new set of parameters in the window that appears b Adjust any of the parameters see Table 2 below for ranges of possible values then click Save 14 c Click Check Calibration The model will rerun the process should only take a minute or two this time and you can compare the results for the new set against the others Continue in this way until you are satisfied with the calibration d Having too many parameter sets saved can slow down the modeling You can delete sets by selecting the one to be deleted from the drop down menu and clicking Delet
5. To begin click Input gt Configuration 1 On the Initial Setup tab a Choose a routing method There are two options here time constant routing and channel routing The routing method is the means by which the program adjusts the timing of the flow to reach the watershed gauging station at the proper time e g precipitation at the top of the watershed takes longer to reach the bottom of the watershed than precipitation that falls near the bottom of the watershed The time constant routing method uses a physical function or equation to find the best fit for time and flow The channel routing method divides the watershed into 16 zones and requires 18 parameters to be calibrated The time constant routing method only requires one parameter to be calibrated and is more efficient Both methods produce similar results b Load your DEM weather and stream gauge data by browsing to find the location of these files If you chose the Channel Routing method in the step above click Create next to the Channel Routing field In the dialog box navigate to the location where you want to save the file that will be created give it a name and click Save Then click Browse navigate again to the file and click Open 2 On the Current Land Cover tab enter the data you collected in Phase in each field Use default values when data are unknown 3 Check the Show Advanced Settings button and an Advanced Settings tab will appear If you have more local i
6. which nationally characterizes urban runoff for 10 standard water quality pollutants based on data from 2 300 station storms at 81 urban sites in 28 metropolitan areas Two important conclusions from NURP investigations The variance of the EMCs when data from sites are grouped by land use type or geographic region is so great that difference in measures of central tendency among groups statistically are not significant Statistically the entire sample of EMCs and the medians of all EMCs among sites are lognormally distributed Thus the numbers in Table 3 do not distinguish between different urban land use types Subsequently the USGS created another urban stormwater runoff base Driver et al 1985 based on data measured through mid 1980s for over 1 100 stations at 97 urban sites located in 21 metropolitan areas Additionally many major cities in the United States 28 collected urban runoff quality data as part of the application requirements for stormwater discharge permits under the National Pollutant Discharge Elimination System NPDES The NPDES data are from over 30 cities and more than 800 station storms for over 150 paramaters Smullen et al 1999 The data from the three sources NURP USGS and NPDES were used to compute new estimates of EMC population means and medians for the 10 pollutants with many more degrees of freedom than were available to the NURP investigators Smullen et al 1999 A pooled mean was
7. Determine your watershed of analysis and stream gauge station i Tree Hydro works on a watershed basis with the watershed determined as the total drainage area upstream from a measured stream gauge Stream gauge availability varies 2 Download national digital elevation data Once the area and location of the watershed are known digital elevation data are downloaded from the USGS for an area that encompasses the entire watershed ArcGIS software is then used to create a digital elevation map and to determine the exact boundary for the watershed upstream from the gauge station location 3 Determine cover attributes of the watershed and gather other required data i Tree Canopy and other sources can be used to determine the tree cover shrub cover impervious surface and other cover types Information about other aspects of the watershed such as proportion of evergreen trees and shrubs leaf area index and a variety of hydrologic parameters must be collected 4 Get started with Hydro Once these input data are ready they are loaded into Hydro to begin analysis 5 Calibrate the model The Hydro model contains an auto calibration routine that tries to find the best fit between the stream flow predicted by the model and the stream flow measured at the stream gauge station given the various inputs The model can also be manually calibrated to improve the fit by changing the parameters as needed 6 Model new scenarios Once the model is prope
8. Impaired W 3 305 b Assessed Waters i Je Is Earth Gallery gt gt Primary Database Borders and Labels EP Borders International Borders VP country Names Coastlines a e 1st Level Admin Borders d L yi t 1st Level Admin Names 5 7 EEN 5 xt G O andLevel Admin Regions mE Ie E p Y 300 jle Labels 3 mi 5 v tu E 1 r d 1 VE S 7 Bl Places Date Jun 39423476 N10 2197W elev 5296 Eye alt 23 2 Fig 1 Streams and stream gauge stations around Denver 4 The next step is to explore the watersheds associated with each station to choose the best one To do this a Click on the stream itself just downstream of the station A window will appear describing the features of the stream At the bottom under Tools click Drainage Area Delineation b In the window that appears choose Stop When Maximum Distance KM 30 and click Start Search The watershed upstream from that point for the first 30 km will be identified You might have to redo this process a few times increasing the maximum distance to capture the entire watershed see Fig 2 FlyTo Find Businesses Directions Fly to e g 1600 Pennsylvania Ave 20006 denver co x ID denver co ge v Places L1 3 Monitoring Locations L1 amp No Discharge Zones CE Nonpoin
9. calculated representing the mean of the total population of sample data The NURP and pooled mean EMCs for the 10 constitutes are listed in Table 3 Smullen et al 1999 NURP or pooled mean EMCs were selected because they are based on field data collected from thousands of storm events These estimates are based on nationwide data however so they do not account for regional variation in soil types climate and other factors Table 3 National pooled EMCs and NURP EMCs Constituent Data EMCs No of source Mean Median events Pooled 78 4 54 5 3047 Total suspended solids TSS NURP 17 4 113 2000 Pooled 14 1 11 5 1035 Biochemical oxygen demand BOD NURP 10 4 8 39 474 Pooled 52 8 44 7 2639 Chemical oxygen demand COD NURP 66 1 55 1538 Pooled 0 315 0 259 3094 Total phosphorus TP NURP 0 337 0 266 1902 Pooled 0 129 0 103 1091 Soluble phosphorus soluble P NURP 0 1 0 078 767 Pooled 1 73 1 47 2693 Total Kjeldhal nitrogen TKN NURP 1 67 1 41 1601 Pooled 0 658 0 533 2016 Nitrite and nitrate NO and NO NURP 0 837 0 666 1234 29 Constituent Data EMCs No of source Mean Median events Pooled 13 5 11 1 1657 Copper Cu NURP 66 6 54 8 849 Pooled 67 5 50 7 2713 Lead Pb NURP 175 131 1579 Pooled 162 129 2234 Zinc Zn NURP 176 140 1281 Polled data sources include NURP USGS NPDES No BOD data available in the USGS dataset pooled includes NURP NPDES
10. cover are likely to be overwhelmed by other influences d Delineate the drainage areas for other stream gauge stations until you have found the best one see Fig 3 5 Once you have made your selection a Note the name of the stream b Note the ID number of the stream gauge station by clicking on its red dot c Capture an image of the stream gauge station and watershed using your computer s Print Screen function or Google Earth s File gt Save gt Save Image function Once you have identified your watershed of interest and noted the stream gauge station number and stream name your next step is to create a digital elevation model DEM of the watershed The end product should be a DEM clipped to the boundaries of your watershed projected in the proper UTM zone in meters and converted to ASCII format For detailed instructions on this process see Appendix 1 Streamflow weather and evapotranspiration data Hourly streamflow weather and evapotranspiration data are available as standardized complete data sets within Hydro for the year 2005 If you are amenable to working with data from this year your work in this regard is done If you wish to run the model for a different year you will need to gather and format the hourly data for your year of choice Required weather data include wind direction and speed cloud ceiling sky cover temperature dewpoint altimeter setting pressure and precipitation for streamflow hourly va
11. more likely it is to timeout forcing you to begin again so don t go overboard 8 In the window that appears click the Download button Depending on server load and the size of your download this request may take some time 9 Save the file and unzip to a working folder The National Map Seamless Request Summary Page Mozilla Firefox o The National Map Seamless Server The National Map Seamless Server Download Request Status Mozilla Firefox Request Summary Page D Gat yew Hatery Bookmarks Tools tb You are logged in as Default Seamless User The National Map Seamless Server Modify Data Request The data extraction has c yyy EN You have chosen to open MED 720146922ip 3 Sere TUA National Elevation Dataset NED 1 Arc Second If an error occurs during download clic from http 152 61 128 141 After one hour the download bundle wil Pet shoud Firefox do with this fie C Qpen with PR Save File Do this automatically for files lice this from now on x c 21 File Edt View Tools Add Help v Search Fly To Busine ns Fly to e g 1600 Pennsylvania Ave 20006 denver co Q denver co o x v Places T amp S monitoring Locations L1 amp 8 No Discharge Zones 1S Nonpoint Source Projects L1 water Quality Standards OE tegend EPA Logo amp Drainage Area Delineation Results 02 22 2011 19 36 58 Drainage Area amp Qranage Area D
12. to help urban foresters select the most appropriate tree species based on environmental function and geographic area i Tree Storm helps you to assess widespread community damage in a simple credible and efficient manner immediately after a severe storm It is adaptable to various community types and sizes and provides information on the time and funds needed to mitigate storm damage i Tree Design beta is a simple online tool that provides a platform for assessments of individual trees at the parcel level This tool links to Google Maps and allows you to see how tree selection tree size and placement around your home effects energy use and other benefits This beta tool is the first stage in development of more sophisticated options that will be available in future versions i Tree Canopy offers a quick and easy way to produce a statistically valid estimate of land cover types e g tree cover using aerial images available in Google Maps The data can be used by urban forest managers to estimate tree canopy cover set canopy goals and track success and to estimate inputs for use in i Tree Hydro and elsewhere where land cover data are needed All beta programs are still in development therefore feedback is particularly appreciated The use of trade firm or corporation names in this publication is solely for the information and convenience of the reader Such use does not constitute an official endorsement or approval by the U S Dep
13. 600 Software Windows XP service pack 2 or higher OS including Windows 7 Microsoft Excel Microsoft Data Access Component MDAC 2 8 or higher included in installation NET 2 0 framework included in i Tree installation Adobe Reader 9 0 ArcGIS with Spatial Analyst Extension To install Hydro 1 Visit www itreetools org to download the software or insert the i Tree Installation CD into your CD ROM drive 2 Follow the on screen instructions to run i Tree setup exe This may take several minutes depending on which files need to be installed 3 Follow the Installation Wizard instructions to complete the installation default location recommended You can check for the latest updates at any time by clicking Help Check for Updates Now that you ve installed Hydro you would probably like to see a little of what the software can do To allow you to explore the program we ve included a sample project based on a watershed near Denver CO 1 You can begin by opening Hydro using your computer s Start menu gt All Programs gt i Tree gt i Tree Hydro 2 You will find the project under File Open Sample Project a Under Input you can explore some of the data fields that can be edited b Under Reports Water Flow Reports Current Scenario you can run the model for the current conditions for this watershed As an output you will receive a graph showing how water flow and rainfall vary over time c To ad
14. IS department Literature Some data may be available for some areas in the scientific literature or from the appropriate university department gt Leaf area indexes can be calculated from Eco results for leaf area These results are presented in units of m ha To get LAI divide by 10 000 This value can be particularly difficult to find One strategy is to adjust the value in the calibration process until the best results are achieved 11 Once you ve created your DEM and gathered your data it s time to get started with the software To begin working with Hydro click your computer s Start menu gt All Programs gt i Tree gt Hydro To start a new project 1 Click File New project and then Input Raw Data Input The i Tree Hydro Raw Data Input window will appear In this window you will load the appropriate stream gauge and weather data for your area and provide inputs that allow these files to be processed To locate your stream gauge and weather data enter the state county and city that is closest to your watershed Enter the watershed land area in square meters from the DEM process in Appendix 1 and the percent tree cover in the watershed leaf area index and percent of the tree and shrub cover that is evergreen Note that percent evergreen tree and shrub cover can range from 0 all of the tree or shrub cover is deciduous to 100 all of the tree or shrub cover is evergreen If you will be providing
15. M Drag the point so that it sits within the primary outlet stream of your watershed The distance should be fairly small and the move obvious If not verify that you have entered the coordinates correctly Now drag the pour point slightly downstream 50 100 feet to simplify later steps Hix File Edit View Bookmarks Insert Selection Tools Window Help Deke amp mx o amp 13 109 7 2 90 2x Spatial Analyst L E amp Layers a Cartography Tools a a 30 IndGaugeStation Qp Conversion Tools pur amp e 3 Data Interoperability Tools ai E pourpt b Data Management Tools MN el S Geocoding Tools Ka 0 Watersh_Flow8 Ag Geostatistical Analyst Tools WE Move pour point 0 pun Gp Linear Referencing Tools e int t 0 Watersh Flow7 Mobile Tools Into stream Mo Multidimension Tools and 50 100 ft Watersh_Flow6 Network Analyst Tools 4 208 000 Qi Samples downstream O Watersh Flow5 Qi Schematics Tools gm Eo Server Tools O Watersh_Flow4 3 Spatial Analyst Tools Mio amp Conditional k O cuyfallsws amp Density e Value z amp Distance d B Extraction Streamflow Display Source amp Generalization m Selection Map Book Favorites Index Search Results amp lam ene gt Get help on the menu command or tool you select 81 63 41 397 Decimal Degrees Capture this pour point
16. al values More information about the methods used to estimate these values can be found in Appendix 2 It is important to note that these are national values and therefore do not take into account local pollutant conditions and local management actions such as street cleaning It is not known how well the national EMC values represent local conditions 18 1 To model the pollutant load in your receiving body of water i e in the water moving past your gauging station under Reports in the File menu click Water Pollution Reports gt Current Scenario 2 To model the pollutant load under your management scenario under Reports in the File menu click Water Pollution Reports gt Management Scenario 3 To compare the two under Reports in the File menu click Water Pollution Reports gt Management Current Scenario Graphs and tables The graphs and tables for pollutant load are similar to those for hydrology On the graphs rainfall appears at the top and is associated with the values on the right y axis The ten modeled pollutants appear at the bottom of the graphs and are associated with values on the left y axis As for the hydrology results graphs and tables can be exported in a variety of formats NOTE A limitation of the current beta version of Hydro is that only one management scenario can be saved at a time If you wish to model several different scenarios we suggest saving each as a new project under File gt Save Pro
17. ally Sansalone and Buchberger 1997 Charbeneau and Barretti 1998 Bugs co oo Y co ooa V oma 390 where C t and Q t are the time variable concentration and flow measured during the runoff event and M and V are pollutant mass and runoff volume as defined in Equation 1 It is clear that the EMC results from a flow weighted average not simply a time average of the concentration EMC data is used for estimating pollutant loading into watersheds EMCs are reported as a mass of pollutant per unit volume of water usually mg l The pollution load L calculation from the EMC method is L EMC Q EMC d A where EMC is event mean concentration mg l mg m O is runoff of a time period associated with EMC l h m day d is runoff depth of unit area mm h m h m day A is the land area m which is catchment area in i Tree Hydro Thus when the EMC is multiplied by the runoff volume an estimate of the loading to the receiving water is provided As is evident from Fig 3 the instantaneous concentration during a storm can be higher or lower than the EMC but the use of the EMC as an event characterization replaces the actual time variation of C versus in a storm with a pulse of constant concentration having equal mass and duration as the actual event This process ensures that mass loadings from storms will be correctly represented EMCs represent the concentration of a specific pollutant contained in stor
18. an Concentration to Calculate Pollution Load References 20 20 23 27 30 i Tree Hydro is the first urban hydrology model that is specifically designed to model vegetation effects and to be calibrated against measured stream flow data It is designed to model the effects of changes in urban tree cover and impervious surfaces on hourly stream flows and water quality at the watershed level Note i Tree Hydro differs from other i Tree products in several ways Its analysis area is confined to a watershed Unlike other i Tree tools you cannot define your own boundary for analysis rather you must pick a watershed with gauging station flow data To make the best use of Hydro you should have an understanding of hydrology and watersheds Considerably more technical expertise is necessary for the data preparation in Hydro than in other i Tree tools In particular you must be able to procure and properly format a digital elevation model DEM for the watershed More technical expertise is necessary to make use of the outputs from Hydro Results are presented as changes in hourly stream flow or water quality in tabular or graphic format This program is a beta version i e it is still in development and feedback is appreciated The purpose of i Tree Hydro is to simulate hourly changes in stream flow and water quality given changes in tree and impervious cover in the watershed The following is an overview of the process 1
19. artitioning and first flush of metals in urban roadway storm water J Environ Eng ASCE 123 134 143 30 Smullen J T Shallcross A L and Cave K A 1999 Updating the U S nationwide urban runoff quality database Water Science Technology 39 12 9 16 U S Environmental Protection Agency USEPA 1983 Results of the Nationwide Urban Runoff Program Volume final report U S Environmental Protection Agency PB84 185552 Washington DC U S Environmental Protection Agency USEPA 2002 Urban Stormwater BMP Performance Monitoring A Guidance Manual for Meeting the National Stormwater BMP Database Requirements 31
20. artment of Agriculture or the Forest Service of any product or service to the exclusion of others that may be suitable The software distributed under the label i Tree Software Suite v 4 0 is provided without warranty of any kind Its use is governed by the End User License Agreement EULA to which the user agrees before installation The i Tree Development Team actively seeks feedback on any component of the project the software suite itself the manuals or the process of development dissemination support and refinement Please send comments through any of the means listed on the i Tree support page http www itreetools org support i Tree Components of the i Tree software suite have been developed over the last few decades by the USDA Forest Service and numerous cooperators Support for the development and release of i Tree v 4 0 has come from USDA Forest Service Research State and Private Forestry and their cooperators through the i Tree Cooperative Partnership of Davey Tree Expert Company the Arbor Day Foundation Society of Municipal Arborists the International Society of Arboriculture and Casey Trees i Tree Hydro The i Tree Hydro model was originally developed by Drs Jun Wang SUNY ESF Ted Endreny SUNY ESF and David J Nowak USDA Forest Service The model code has been improved and integrated within i Tree based on the work of Michael Kerr Davey Institute Yang Yang SUNY ESF Sanyam Chaudhary Syracuse U
21. by Points High 422 53 i 167 45 O Watersh Flow8 Jo O Watersh Flow7 Extract by Polygon Extract by Rectangl Extract Values to Pc A Sample amp Generalization amp Groundwater Ho Hydrology M Watersh rime El w Interpolation b 5 Q Local Du 81 787 41 756 Decimal Degrees 13 Re project the clipped DEM from step 11 to UTM meters using ArcToolbox gt Data Management Tools gt Projections and Transformations gt Raster gt Project Raster a The UTM zone is dependent on the project area For UTM zones guidance http egsc usgs gov isb pubs factsheets fs07701 html b Output coordinate system should be WGS_ 1984 datum c Geographic transformation should be NAD 1983 TO WGS 1 d Leave other values as defaults 14 Export the clipped re projected DEM from step 12 to ASCII format using ArcToolBox Conversion Tools From Raster Raster to ASCII 15 In Windows Explorer change the file type extension of the ASCII file from step 13 from TXT to DAT for use within i Tree Hydro 26 The term event mean concentration EMC is a statistical parameter used to represent the flow proportional average concentration of a given parameter during a storm event It is defined as the total constituent mass divided by the total runoff volume although EMC estimates are usually obtained from a flow weighted composite of concentration samples taken during a storm Mathematic
22. ductivity m h 0 00006 0 2 0 002 Impervious depression storage mm 0 1 3 0 1 5 Graphing the calibration results The different calibration schemes can be compared in graph form under Reports gt Calibration Comparison A window will open allowing you to choose which calibration parameter sets to compare Select the desired ones and click OK The resulting graph shows rainfall at the top with rainfall values along the right y axis Measured stream flow from the stream gauge station and estimated stream flow according to the different parameter sets are on the bottom of the chart and are associated with the values on the left y axis The x axis is time 16 Once you are satisfied with the calibration settings you can run the model for your existing conditions 1 Under Reports in the File menu click Water Flow Reports gt Current Scenario 2 You can switch between English and metric units in the tool bar under View Graphs The graph shows rainfall at the top with rainfall values along the right y axis Stream flow curves are on the bottom of the chart and are associated with the values on the left y axis The x axis is time Stream flow is the amount of water moving past the gauging station and includes base flow water in a stream provided by groundwater overland flow excess water that moves over pervious surfaces when precipitation rate is greater than infiltration rate and or when the ground is saturated impervious flow wate
23. e Parameter Set Once you have successfully calibrated your model and entered the necessary data under each field you have the option of saving all of your parameters including the currently visible calibration values land cover values advanced settings etc so they can be viewed outside of Hydro or used in another project To save for outside use click Save to File To load the saved parameters from a previous project click Load from File To move on to the next phase be sure that the desired parameter set has been selected in the dropdown menu click OK to close the Configuration window and be sure to save your project Table 2 Hydrological parameters used in calibration Parameter Range Default Scale parameter of power function n 2 Scale parameter of soil transmissivity m 0 001 0 25 0 03 Transmissivity at saturation 7 m h 0 001 100 0 2 Unsaturated zone time delay T h 0 01 200 10 Maximum root zone storage deficit 0 0001 0 5 0 022 Ade buda generating infiltration 0 100 30 Time constant of watershed b h 0 1 240 1 Initial stream discharge Q m h 0 000001 0 00005 0 000015 Initial root zone deficit m 0 00001 0 03 0 0002 Main channel routing velocity m h 500 3600 950 Internal channel routing velocity m h 500 3600 950 Wetting front suction m 0 01 0 3 0 12 15 Parameter Range Default Wetted moisture content m 0 1 0 7 0 48 Surface hydraulic con
24. elneation Results v w Layers Earth Gallery gt gt amp Primary Database V Borders and Labels V Borders International Borders OP Country Names X i L Coastlines 7 7 1st Level Admin Borders OOP ist Level admin Names 6 s duros ross JEn SIR and Level Admin Regions 5 D Labels OG Places magety Date Jun 16 20 z 39 35 57 62 N mage Fig 1 Watershed boundaries determined in Phase using Google Earth EPA stream file and Hydro stream gauge file Scale Information Out Scale 1 270 981 oisptay ge s 2 EIE ss fl Click and drag to select area to download Fig 2 The same stream system The outlined area includes all of the yellow area in the figure above 22 Once you have your data downloaded and unzipped you can begin the process of transforming it into a hydrological model and clipping it in ArcGIS You ll need to load and enable the ArcGIS Spatial Analyst Hydrology Tools 1 Open the DEM data in ArcMap Do NOT set any projection information at this time 2 Open ArcToolBox and navigate to Spatial Analyst Tools gt Hydrology Untitled ArcMap Arcinfo a x Dd WX cs Liege Q Spatial Analyst Tools amp Conditional
25. ges are located in streams that capture water from watersheds of vastly different scales A stream gauge in a small creek might be associated with a watershed of a few square kilometers A stream gauge at the mouth of the Mississippi River would be associated with a watershed that includes half of the United States Changes in tree cover and impervious surface are unlikely to have measurable effects over the scale of a very large watershed therefore your goal should be to analyze a watershed that is of a size that can be influenced by changes in these factors With these limitations in mind your goal in this first step is to choose the best stream gauge station in your area of interest and estimate the boundaries of the associated watershed You ll use these boundaries for the next part of Phase obtaining digital elevation model data Tools for choosing the best stream gauge station and watershed The easiest method for visualizing stream gauge stations and their associated watersheds is Google Earth Begin by downloading the two files necessary 1 At the EPA s Waters website http www epa gov waters tools WATERSKMZ WATERSKMZ html download the WATERS KMZ file in vector format NOTE Links were correct at time of publication but may have changed If necessary please use an internet search engine and relevant key words to search for the correct links 2 From www itreetools org gt Resources gt Archives under the Hydro section down
26. hat the covers total 100 Click OK 3 To view the results under Reports in the File menu select Water Flow Reports gt Management Scenario The Hydro Model Run window will appear Agraph and table similar to those for the initial scenario will appear showing the values for the new scenario Comparing the initial and management scenarios The initial and management scenarios can be compared by choosing Management vs Current Scenario under the Reports gt Waterflow Reports menu To illustrate the calculated differences in flows between the two scenarios choose Management Current Scenario i Tree Hydro can also help clarify the impacts of changes in surface cover and vegetation on pollutant load in streams by making use of a statistical parameter known as event mean concentration EMC see Appendix 2 for more information An EMC value represents the flow proportional average concentration of a given pollutant during a storm event and is measured in units of mass per volume usually milligrams per liter EMC can be multiplied by actual flow to estimate the mass of pollutants entering a body of water Changes in flow owing to changes in cover and tree canopy will therefore be reflected in changes in pollutant load These are the results that Hydro presents NOTE EMC values can be derived from many sources including actual measured data from your watershed Because such actual data are hard to come by Hydro makes use of average nation
27. i Iree Hydro User s Manual i Tree is a cooperative initiative AL tS DAVEY Arbor Day Foundation RARER LM series i Tree is a state of the art peer reviewed software suite from the USDA Forest Service that provides urban and community forestry analysis and benefits assessment tools The i Tree tools help communities of all sizes to strengthen their urban forest management and advocacy efforts by quantifying the environmental services that trees provide and assessing the structure of the urban forest i Tree has been used by communities non profit organizations consultants volunteers and students to report on the urban forest at all scales from individual trees to parcels neighborhoods cities and entire states By understanding the local tangible ecosystem services that trees provide i Tree users can link urban forest management activities with environmental quality and community livability Whether your interest is a single tree or an entire forest i Tree provides baseline data that you can use to demonstrate value and set priorities for more effective decision making Developed by USDA Forest Service and numerous cooperators i Tree is in the public domain and available by request through the i Tree website www itreetools org The Forest Service Davey Tree Expert Company the Arbor Day Foundation Society of Municipal Arborists the International Society of Arboriculture and Casey Trees have entered into a coope
28. ject As and giving each scenario a different name e g Denver_IncreaseTreeCover30Percent iHydro All variables calibration settings and inputs are saved with the project so it easy to open each one after saving 19 In Phase I we discussed criteria for choosing a watershed and some tools for doing so This Appendix covers the steps necessary to create a digital elevation model DEM of that watershed using ArcGIS These instructions assume that you are familiar with DEM data watershed concepts and ArcGIS tools The basic steps of this procedure are as follows 1 Download DEM data from the USGS for an area that covers the watershed boundaries you determined in Phase I 2 UseArcGIS to build a DEM from the downloaded data and clip it to the borders of the watershed Tools ArcGIS v 9 3 1 was used for this guide but other version can be used ArcGIS Spatial Analyst Results The end product of the steps described here will be a DEM clipped to the boundaries of your watershed projected in the proper UTM zone in meters and converted to ASCII format With your watershed and stream gauge selected using the methods described in Phase the first step in creating a DEM is to download the necessary data from the USGS If you have your own source of DEM data it can certainly be used but keep in mind that DEM data should have a resolution of 10 30 m Finer resolution data are available but are more likely to cause complications i
29. just tree and impervious cover parameters and see how these changes affect the hydrology of the project area click Inputs gt Management Scenario Choose Management Scenario from the drop down menu d Then click Reports gt Water Flow Reports gt Management Scenario to run the model again and see how the graph output changes Other reports allow you to compare the management and current conditions in one graph e Under Reports gt Water Pollution Reports you can view tables and graphs presenting the pollutant load associated with existing and future hydrology We will of course explain all of these functions and more in greater detail but for now feel free to explore and see what s available The first and perhaps most difficult decision you have to make is what watershed to analyze One challenge here is that many people are more accustomed to thinking in terms of political or parcel boundaries e g a city or a university campus and considering what impacts might result from changes to those areas For Hydro modeling occurs at the watershed level which is unlikely to align with political or parcel boundaries Asecond challenge relates to the availability of data Hydro makes use of hourly stream gauge data from the U S Geological Survey USGS Although there are many stream gauge stations across the country data are not available for every stream and its associated watershed A third challenge relates to scale Stream gau
30. load the KMZ file of the stream gauge stations available in Hydro i Tree Hydro Gauging Stations 2005 kmz 3 Open Google Earth on your computer you ll need at least version 5 0 and open the two files Zoom in to your area of interest see Fig 1 A few hints 1 The EPA Waters file is live i e it updates from the internet while you are using it Therefore it can be very slow You ll know it is gathering data when the little colored boxes next to the field names under Places are spinning To speed things up uncheck every box under Surfacewater Features except Streams and all boxes associated with Water Program Features and zoom in to your area 2 The streams are only visible at very local scales If you can t see them continue zooming in until the scale at the bottom of the map is approximately 1 3 miles Remember to wait for the data to load Ele Edit View Tools Add Help v Search Oel FlyTo Find Businesses Directions Fly to e g 1600 Pennsylvania Ave 20006 denver co EQ MS denver co HE mas Wwaw groupen com i 1 ridiculously huge coupon a day Like doing Denver CO at 90 off E denver co 1 Conneaut OH E develand ohio lx vw Places O Drainage Area eth NHD med res Surface Water Landmarks OZ catchments Hydrologic Units 3 amp EPA Water Program Features aos d Listed
31. lues are necessary Custom streamflow and weather data must have the same start and end dates and can be for less than the default option of 1 year More information and examples of correctly formatted data are provided at www itreetools org under Resources gt Archives gt Hydro Other data There are a number of other pieces of information required and optional that are used to calibrate the model The table below lists and defines the data to be collected offers suggestion for where to find local information if desired provides default values where available and provides space for you to enter your own values to make it easier to keep track of your information Category Source Default value Local value Watershed land area m DEM N A Land Cover should total 10096 Eco Canopy U Tree cover 96 UTC GIS N A Eco Canopy U Shrub cover 96 UTC GIS N A Eco Canopy U Herbaceous cover 96 UTC GIS N A Eco Canopy U Water cover 96 UTC GIS N A Eco Canopy U Impervious cover 96 UTC GIS N A Eco Canopy U Soil cover 96 UTC GIS N A Evergreen Contribution Evergreen tree cover as Eco 10 percentage of total tree cover 96 Evergreen shrub cover as Eco 10 percentage of total shrub cover 96 Leaf Area Index Tree leaf area index Eco Literature 5 0 Shrub leaf area index Eco Literature 2 2 Herbaceous leaf area index Eco Literature 1 6 Category
32. mwater runoff coming from a particular land use type or from the whole watershed Under most circumstances the EMC provides the most useful means for quantifying the level of pollution resulting from a runoff event USEPA 2002 Since collecting the data necessary for calculating site specific EMCs can be cost prohibitive researchers or regulators will often use values that are already available in the literature If site specific numbers are not available regional or national averages can be 27 Polstogra ph X f Ekti Conecasbrmeblan C Peeok f feast 2 Sent T RERS Fig 3 Interstorm variation in pollutographs and EMCs used although the accuracy of using these numbers is questionable Due to the specific climatological and physiographic characteristics of individual watersheds agricultural and urban land uses can exhibit a wide range of variability in nutrient export Beaulac and Reckhow 1982 To understand and control urban runoff pollution The U S Congress included the establishment of the Nationwide Urban Runoff Program NURP in the 1977 Amendments of the Clean Water Act PL 95 217 The U S Environmental Protection Agency developed the NURP to expand the state knowledge of urban runoff pollution by applying research projects and instituting data collection in selected urban areas throughout the country In 1983 the U S Environmental Protection Agency U S EPA 1983 published the results of the NURP
33. n modeling associated with bridges and elevated roadways 1 Navigate to the USGS DEM website http seamless usgs gov index php NOTE Links were correct at the time of publication but may have changed If necessary please use Google and the relevant key words to search for the correct links 20 2 Click on the Seamless Viewer to launch the DEM Download Data tool 3 Use the tools on the left to zoom and pan to your region 4 You can use the Display tab on the right to manage visible layers to help with orientation These choices do not affect which data are downloaded The following are recommended a Under Hydrography turn on the National Atlas and NHD Streams option b Under Boundaries turn on National Atlas States and National Atlas Counties 2001 5 Under the Download tab on the right be sure that the 1 NED Elevation data box is checked 6 From the toolbar on the left choose the Define Rectangular Download Area tool 7 Now comparing the image you saved from Google Earth of the streams in your region and your watershed of choice Fig 1 select an area of coverage that extends comfortably beyond the boundaries of your watershed Fig 2 NOTE It is much better to overestimate the size of your watershed when downloading the DEM data than to underestimate because if you miss even a small corner of the watershed you will have to begin again Nevertheless the larger your download size the longer it will take and the
34. nformation for the fields on this tab enter it now a If you would like to save and be able to view the many working files created by Hydro specify the location for the files by checking the box next to Use Specified Working Directory and browse to the location where the 13 files should be saved It s best to create a new folder for them such as Working b Click the Hydrological Parameters tab to begin the steps necessary to calibrate the model Calibrating the model Calibrating the model is a multi step process of adjusting model parameters until the model output for the stream flow is as close as possible to the actual stream flow The model simulates various hydrologic processes e g precipitation interception infiltration evaporation transpiration flow routing and storage to simulate stream flow at the gauging station and then checks how well it has performed by comparing estimated model flow against actual flow Results are considered in terms of peak base and overall flow NOTE Model calibration can be significantly off if the local precipitation data do not match the watershed For example if the precipitation data were collected too far from the watershed or if the precipitation events are very localized calibrations will be off as it may be raining in the watershed but not at the precipitation station or vice versa Begin the calibration process by auto calibrating 1 Click Auto Calibrate Parameters
35. niversity and Rahul Kumbhar Syracuse University Many other individuals have contributed to the design development and testing process including Andrew Lee SUNY ESF Robert Hoehn USDA Forest Service Tian Zhou SUNY ESF Alexis Ellis Davey Institute Mike Binkley Davey Institute Lianghu Tian Davey Institute and Scott Maco Davey Institute The manual was written and designed by Kelaine Vargas Introduction Overview About This Manual Installation System Requirements Requirements for desktop laptop computers Installation Exploring Hydro with the Sample Project Phase I Getting Started Choosing Your Watershed and Gauging Station Tools for choosing the best stream gauge station and watershed Creating a Digital Elevation Model Gathering General Data Streamflow weather and evapotranspiration data Other data Phase Il Getting Started with Hydro Creating a New Project Configuring Your Project Calibrating the model Graphing the calibration results Phase Ill Modeling Scenarios Modeling the Current Scenario Understanding the Graphs and Tables Graphs Tables Modeling Alternative Scenarios Comparing the initial and management scenarios Water Pollution Reports Graphs and tables owmnvnoanounaa h A 00 00 WON Ce O BR ONN 2 2 c 2 c c 0 0 0 NNNNN Appendix 1 Creating a Digital Elevation Model Downloading DEM Data from USGS Working with ArcGIS Appendix 2 Water Quality Effects Event Me
36. onversion Tools Value amp From Raster High 3 0427 AP Raster to ASCII Raster to Float Low 0 Raster to Point O FlowDir_Fill2 Raster to Polygon Raster to Polyline From WFS Gy Metadata To CAD E To Covermge zu S 5tT625 bec Bow ens 4 gt 81 146 41 682 Decimal Degrees 7 10 To calculate the area of the watershed right click the computed watershed layer and select Open Attribute Table Use the table tools to add a new field for area then right click on the added field and select Calculate Geometry Select Area and square meters 11 Convert the derived watershed raster layer from step 8 into a polygon using ArcToolbox gt Conversion Tools gt From Raster gt Raster to Polygon 25 12 Clip the original DEM step 1 with the converted watershed polygon from step 10 using ArcToolbox gt Spatial Analyst Tools gt Extraction gt Extract by Mask NOTE This is NOT the same process as ArcToolbox gt Analysis Tools gt Extract gt Clip Untitled ArcMap Arcinfo E x Eje Edit View Bookmarks Insert Selection Tools Window Help Dema aJe 22 DRM sveta arst Spatial Analyst Tools Layers IndGaugeStation 1 amp Conditional amp y Density E pourpt amp Distance e Extraction O RasterT_Waterst AP Extract by Attribute m AP Extract by Circe E Extract by Mask Value Extract
37. r moving over impervious surfaces and total flow sum of the three component flows You can customize the line colors under Display in the top left corner of the window by clicking the colored box next to each component and then choosing your new color in the window that appears To turn on and off any curves click to remove the check box next to the name This takes a bit of time The legend can be turned on and off using the checkbox at the top of the window Graphs can be exported as GIF JPG or PNG formats by selecting the appropriate file type in the drop down box and clicking Export Tables Tables present the data numerically on an hourly basis Using the Total drop down menu you can choose to display weekly totals monthly totals or a total for the entire model run usually but not always a year Using the Export drop down menu you can choose to export your data in Excel format or as comma separated values CSV 17 The goal of i Tree Hydro is to show how changes in the amount of tree canopy cover or changes in the surface cover transforming impervious surface into herbaceous cover for example affect the hydrology of your watershed To model how different management scenarios affect a watershed s hydrology 1 Under Inputs select Management Scenario From the drop down menu select Management Land Use 2 Make any changes to the surface cover types leaf area indexes and cover types beneath tree cover Be sure t
38. rative partnership to further develop disseminate and provide technical support for the suite The i Tree software suite v 4 0 includes the following urban forest analysis tools and utility programs i Tree Eco provides a broad picture of the entire urban forest It is designed to use field data from randomly located plots throughout a community along with local hourly air pollution and meteorological data to quantify urban forest structure environmental effects and value to communities i Tree Streets focuses on the ecosystem services and structure of a municipality s street tree population It makes use of a sample or complete inventory to quantify and put a dollar value on the trees annual environmental and aesthetic benefits including energy conservation air quality improvement carbon dioxide reduction stormwater control and property value increases i Tree Hydro Beta is the first vegetation specific urban hydrology model It is designed to model the effects of changes in urban tree cover and impervious surfaces on hourly stream flows and water quality at the watershed level i Tree Vue allows you to make use of freely available national land cover data maps to assess your community s land cover including tree canopy and some of the ecosystem services provided by your current urban forest The effects of planting scenarios on future benefits can also be modeled i Tree Species Selector is a free standing utility designed
39. rly calibrated tree and impervious cover parameters can be changed to illustrate the impact on stream flow and water quality For more information on the methodology that underlies Hydro visit www itreetools org gt Resources gt Archives gt i Tree Hydro beta Resources This manual provides all the information needed to conduct a Hydro project We start with installing the software and move on to the three project phases Phase I Getting started In this section we ll talk about decisions you need to make right at the outset how to choose your watershed and what data need to be gathered Phase II Getting started with the software In this section we ll explain how to input your data how to configure a project and how to calibrate the model Phase Ill Modeling scenarios In the third phase we get to the crux of Hydro running the model for your existing scenario adjusting parameters and running alternative scenarios and interpreting the results Appendix 1 The necessary tools and steps involved in creating a digital elevation model using ArcGIS are described here Appendix 2 The methodology associated with estimating how changes in hydrology affect water pollutant levels is presented here Requirements for desktop laptop computers Minimum hardware Pentium or compatible 1600 Mhz or faster processor 512 MB of available RAM Hard drive with at least 500 MB free space Monitor with resolution of at least 800 x
40. t Source Projects OB water Quality Standards OS Legend oe sre L1 02 22 2011 19 36 58 o Jig v Layers Earth Gallery gt ES Primary Database E V Borders and Labels E EI V Borders CI international Borders OP country Names L1 coastines 1st Level Admin Borders OOP ist Level Admin Names 5 DOO and Level Admin Regions e Labels Du Places imagery Date Jun 16 2010 Fig 2 A watershed near Denver 104 50 00 55 W _elevi 5671 ft Eye alt 33 79 mi Bile Edit view Tools Add Help v Search VT Frdunesee recone Fly to e g 1600 Pennsylvania Ave 20006 denver co E 8 MIB denver co e v Places Ue ere Spec L1 02 22 2011 19 38 16 o epe O 02 22 2011 19 45 58 eme M 0242242011 19 48 26 Jg v Layers Earth Gallery gt gt E amp primary Database ag E P Borders and Labels S BP Borders C C international Borders OP country Names L1 coastines V ist Level Admin Borders OOP ist Level Admin Names S OO and Level Admin Regions Labels o E Places 3 Fig 3 Another watershed near Denver 2010 F IAS oogle 3312 mi c Once you have the outline of the watershed determined judge whether it is appropriate for your study Does it capture your area of interest Is the watershed of a scale that would be appropriate for modeling changes in canopy and impervious cover In a watershed that is very large changes in
41. within a shapefile a In ArcCatalog create a new POINT shapefile 9 Set the projection system to that of the original DEM data projection system via the Create Shapefile gt Spatial Reference gt Edit gt Import gt Browse to DEM data option cC Open the Pour Point shapefile in the current ArcMap session 24 d Edit the Pour Point shapefile and create a new point feature right on top of the Pour Point marker Stop editing and save edits 8 Compute the watershed using the flow direction layer created in step 4 and the pour point layer created in step 7 using the Watershed tool not the Basins tool a For the pour point field choose any of the numeric fields although it says that this is optional it isn t 9 Compare the resulting image of the computed watershed with the image of your watershed that you found in Phase I If they are not similar a Try moving the pour point another 50 100 ft downstream and repeating step 8 b Verify that the spatial extent of the original downloaded DEM data covers the entire watershed If it does not you ll need to do another download and perform these steps again Untitled ArcMap Arcinfo Ele Edt Mew Bookmarks Insert Selection Tools Window Heb D y wx lec 1 307 006 E a amp gn KP spatial analyst L ArcToolbox 3D Analyst Tools FH g Analysis Tools v Watersh Flow8 Ag ArcPad Tools Lo QU Cartography Tools O FlowAcc Flow3 5 C
42. your own stream gauge and weather data enter the start and end times of the data sets Note that they must be the same for both sets If you are using the standard option leave the defaults as they are The next step relates to incorporating your stream gauge and weather data Here you have two options a If you will be using the standard Hydro data for 2005 click Select by Map For both stream gauge and weather data a map of local stations will appear Either click on the appropriate station or enter the ID number directly in the ID field and click OK A window will appear allowing you to choose the location and a name for the file Navigate to the folder where your project will be saved give the file a name e g streamgauge data dat weather data dat and click Save Processing will begin b If you gathered your own data choose Select File and browse to the location where you saved the file 12 NOTE If you should discover later that you made an error in any of the fields in this window you should start over with a new project as changes to these fields require reprocessing of weather and stream gauge data Once you have finished in this window click OK to close It s a good idea to save your project at this time so click File gt Save Project navigate to the folder where you want to save give the project a name and click Save The next step involves configuring the model by giving more specific details on your watershed
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