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Appendix G – SMR Hydrology Model Guidance Manual

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1. Ct rd antt Da a o i To exit SMRHM click on File in the upper left corner and select Exit Or click on the X in the red box in the upper right hand corner of the screen 34 Santa Margarita Region Hydrology Model Guidance April 2014 MAIN SCREENS SMRHM has six main screens These main screens can be accessed through the buttons shown on the tool bar above or via the View menu The six main screens are Map Information General Project Information Analysis Reports Tools LID Low Impact Development Analysis Each is discussed in more detail in the following sections 35 Santa Margarita Region Hydrology Model Guidance April 2014 MAP INFORMA TION SCREEN piuummiews uHkooov oae Poco Fc 13 7 2003 1 50PM 8 The Map screen contains county information The precipitation gauge and precipitation factor are shown to the right of the map They are based on the project site location The user can provide site information optional The site name and address will help to identify the project on the Report screen and in the printed report provided to the local municipal permitting agency The user locates the project site on the map screen by using the mouse and left clicking at the project site location Right clicking on the map re centers the view The and buttons zoom in and out respectively The cross hair button zooms out to the full county view The arrow ke
2. Eje dt View Hep Summary Report D cb X umm pugaum ugus5isusmgiu i ie SS Wl Schematic Ex trapezoidal Pond 1 Mitigated Facility Name Facility Type Outlet 1 Outlet 2 Outlet 3 Downstream Connections p 18 J F Pecetaton coito Fact Lead outs h Evaporation Applied to Facility Facility Dimensions Fachty Bottom Elevation It Thoi l Pond Depth imcl 1 ft freeboard 4j ft Pond length to width ratio Y to 1 Pond Side Slopes 3 to1 Bottom Length les 553286 ft Bottom wisn 54553000 Volume at mer head 2758 acre ft 45 FL CONV offs 1 orifice amp rectangular notch Progrezz Performing iberalion 3 of an estimated 300 malas Eon T Choose Outlet Structure NOE 4 10E 3 10E2 106 1 1 10 Peroent Time Exofeding Overflow Elevation f fr herations 5 4 2013 355 AM Flow duration results are shown in the plots above The vertical axis shows the range of flows from 10 of the 2 year flow 0 40 cfs to the 10 year flow 8 66 cfs The horizontal axis is the percent of time that flows exceed a flow value Plotting positions on the horizontal axis typically range from 0 001 to 1 as explained below For the entire 30 to 50 year simulation period depending on the period of record of the precipitation station used all of the 15 minute time steps are checked to see if the flow for that time step is greater tha
3. Fie EM Yie Help Summary Report Duk X bw m ASHE Oe BS BEE TOD a a Save in C proas cf EB pama El nfie txt Text Fle bd Comma Delmted eav Stat Date End Date paano 00 00 2011 03 30 24 00 Timestep Out Hour SUM AVG Close i The user provides a file name and the format or type of file The file type can be ASCII text comma delimited Access database recharge SWMM or WWHM Click Save to save the exported time series file 108 Santa Margarita Region Hydrology Model Guidance April 2014 This page has been intentionally left blank 109 Santa Margarita Region Hydrology Model Guidance April 2014 LID ANALYSIS SCREEN SMRHM Example Sessa Ou SP BEBE DAO scenano beneralor PERLND NAME C D Urban Moc 5 1056 v Urs oi Inches Units of Acre Fi x Tice Gate Elevation ff lU Downstream Connection Save 7 Load T Overflow Elevation ff lo Meralions 6 4 2013 420PM The LID tool bar button farthest on the right brings up the Low Impact Development Scenario Generator screen The LID scenario generator can be used to compare the amount of runoff from different land types and combinations The user can quickly see how changing the land use affects surface runoff interflow groundwater and evapotranspiration NOTE The LID scenario generator works only in the Mitigated scen
4. 28 poo poo pot poo p50 pao pot 29 ooo poo pot poo 350 150 pto 380 1 poo poo pot poo 350 150 pio 31 poo poo pot 000 B50 150 010 32 poo poo pot poo 350 150 pio 33 11 poo poo pot poo pso pao pot 34 poo poo pot poo pso pao pot 385 poo poo pot poo ps5o paso Q0 36 1 0 poo poo pot poo pso pao pot 37 poo poo pot poo ps5o poso poo 388 1 poo poo pot poo pso pao pot 39 poo poo pot poo pso pao pot 40 poo poo pot poo ps5o poso po 41 poo poo pot poo pso pao pot 42 poo poo pot poo pso pao pot 43 poo X poo pot poo ps0 p3o pot 44 poo poo pot poo pso pao pot 45 poo poo X pot poo 50 170 fo 149 Appendix A Santa Margarita Region Hydrology Model Guidance June 2013 46 0 00 0 00 0 01 0 00 3 50 1 70 0 10 CEPS Initial interception storage inches SURS Initial surface runoff inches UZS Initial Upper Zone Storage inches IFWS Initial interflow inches LZS Initial Lower Zone Storage inches AGWS Initial Active Groundwater storage inches GWVS Initial Groundwater Vertical Slope feet feet 150 Appendix A Santa Margarita Region Hydrology Model Guidance June 2013 Table 6 SMRHM HSPF Pervious Parameter Values Monthly Interception Storage inches PERLND No DAN FEB MAR jen MAY UN pu pue See ocr Nov pec pis pis bis ba x 2 pis pis brs b pe
5. ZIET Bottom sope of Swala ILA Outlet Structure Data Top and Bottom side dope vit oe Fiser Height Above Swale surtace ft n5 Left Side Slope H V Aer Diameter fr 24 RueTye eg Material Layers for Swale Notch Type Layer Layer Laper3 0 280 2000 pw Pest mended 5 inh Orfice Diameter Height ft A Number in MS 1 fo p Edit Soil Types 2 p h KSal Safety Factor 3 np a CE 4 None 02 C4 Show Swale Table OpenTable H Swale Volime at River Head ac ft 103 GRAVEL Native Infiltration MO iv Ra 6 5 2013 2 23PM The bioretention dimensions and parameters to adjust to represent the bioretention standard design are discussed on page 81 The Riverside County Design Handbook for Low Impact Development Best Management Practices specifies the following criteria for bioretention standard design Minimum width 6 ft Sideslope 4 to 1 Maximum ponding depth 0 5 ft Mulch top layer 2 to 3 inches deep above amended soil layer Minimum amended soil layer depth 1 5 ft Maximum amended soil layer depth 3 ft Maximum amended soil porosity 0 30 Maximum gravel layer 1 ft below amended soil layer Gravel layer porosity 0 40 Minimum underdrain diameter 0 5 ft No infiltration to native soil 129 Santa Margarita Region Hydrology Model Guidance April 2014 BIORETENTION VERTICAL SIDESLOPES VARIES 2 MINIMU
6. 135 Santa Margarita Region Hydrology Model Guidance April 2014 EXTENDED DETENTION BASIN SIDE SLOPES NO STEEPER THAN 4H 1V LAN SOSTE RES OESIE GUE NCS gt PERFORATED PIPE ISSUED BY THE ENGINEERING AUTHORITY AS SUBDRAIN EA OR PLANNING AUTHORITY RETA Ces IBW X 24 D COLLECTOR TRENCHES AT 25 O C MAX has MIN FOREBAY VOLUME E al id SECTION A A SURFAC SIZE NOTCH TYPE WEIR LOW FLOW TRENCH INFLOW EE E AY INVERT OF GRAVEL FILLED OW FLOW MIN BOTTOM STAGE TRENCH VOL 0 5 V tmp 3 BERM WALL INFLOW 7 y e UUXi1e ah A r BASIN VOLUME 7 WATER SURFACE PAVED BOTTOM 18 W X 24 D GRAVEL FILLED COLLECTOR TRENCH OUTLET WORKS SEE WQ501 DETAILS DRAWING NOTES AASHTO NO 57 OR 67 COARSE AGGREGATE LAYER FINE AGGREGATE PER ASTM C 33 AASHTO NO 2 GRAVEL LAYER GENERAL NOTES SECTION PERFOR A 4 SEE RIVERSIDE COUNTY FLOOD CONTROL m pci oe OR ee a OE CTOR UNDERDRAINS CH 2 SEE RIVERSIDE COUNTY FLOOD CONTROL DISTRICT S APPENDIX C BASIN GUIDELINES FOR ADDITIONAL GENERAL BASIN INFORMATION FILTER DRAIN Figure courtesy of Riverside County Flood Control and Water Conservation District The extended detention basin is a combination stormwater pond forebay gravel trench connector trench and sand filter filter drain In SMRHM there is not a single element that represents this combination 136 Santa Margarita Region Hydrology Model Guidance April 2014 In
7. APPENDIX B DEFAULT SMRHM HSPF IMPERVIOUS PARAMETER VALUES 157 APPENDIX C ADDITIONAL GUIDANCE FOR USING SMRHM 161 Intiltratton Reduction Pacto is pe E PU me mau od 161 Flow Duration Outlet Structures Practical Design Considerations 162 Drawdown time and treatment vector considerations ccooooooonnnnnnnncnnnnnnnonnnnnnnnnnnnnanos 163 APPENDIX D SMRHM REVIEWER CHECKLIST eeeeeeeerm 167 APPENDIX E SMRHM BACKGROUND esses nennt nnn nennen 169 Effects Of Hy drOmOditi Cat Oi sli 169 Development of the Santa Margarita Region Hydrology Model 169 SMRHM OVERVIEW ra od 170 BIORETENTION MODELING METHODOLOGY 1 eene 172 vi Santa Margarita Region Hydrology Model Guidance April 2014 ACRONYMS and ABBREVIATIONS Active Groundwater Recession Constant per day PNE CAN BOCIEN of S Engineers Ar O Tributary Area eee Area Bus Base Flow from groundwater Evapotranspiration Fraction BMP Best Nana Eset Practice C Runoff Coefficient S CCS Clear Creek Solutions S Comeeti n Pacto O OOOO CFS Cubic Feet per Second d Surface ponding depth fee o Development S O Dev Development DMA Drainage Management Area Das 85 percentile 24 hour rainfall depth Foot GWVS Initial Groundwater Vertical Slope feet feet Hydraulic head feet Hydraulic head fee HMP_ Hydromodification Managem
8. Onfice Diameter Height lanae Number in tt A lS o s EditSoil Types 2 o h KSal Safety Factor 3 p h None C2 fa Show Swale Table Open Table 4 Swale Volume at River Head aci Native Infiltration mo e Save xy Load xy val dB 5 4 2013 330 PM The amended soil layer fills with stormwater runoff from the top on down to where it can drain to the native soil if Native Infiltration is set to YES and or the underdrain pipe if Underdrain Used box is checked Water enters the underdrain when the amended soil becomes saturated down to the top of the underdrain The underdrain pipe fills and conveys stormwater runoff proportionally to the depth of amended soil saturation When the amended soil is fully saturated the underdrain pipe is at full capacity Discharge from the underdrain pipe is controlled by the underdrain orifice diameter If native infiltration is turned on then native infiltration will start when if stormwater runoff m starts to fill the underdrain 1f an underdrain is used enters the amended soil if Use Wetted Surface Area sidewalls is set to YES 3 saturates the amended soil layer s to 2 3rds of the total amended soil depth 1f there is no underdrain and Wetted Surface Area is set to NO p 83 Santa Margarita Region Hydrology Model Guidance April 2014 Santa Margarita Region Hydrology Model Dae ba pasa Ow sa iz
9. Facility Name Downstream Connection Orifice Diameter Height Humber in tt 1 fo B 4 2 jo fo 4 TE Volume al Top of Storage wea acA Show Splitter Table Initial Stage It Save xy Losdxy mm Hd Prenary Ex 1 Secondary Exi 2 Trapezoidal Pond 1 Channel 1 no d Secondary Exit 2 Structure Control Structure H Riser Heagh It fo x Riser Diameter im p H RierType Fin H Diameter Height in ft 1 f sh 4 2 lo 4h 3b cp 5 4 2013 303 PM The flow splitter divides the runoff and sends it to two different destinations The splitter has a primary exit exit 1 and a secondary exit exit 2 The user defines how the flow is split between these two exits The user can define a flow control structure with a riser and from one to three orifices for each exit The flow control structure works the same way as the pond outlet structure with the user setting the riser height and diameter the riser weir type flat rectangular notch V notch or Sutro and the orifice diameter and height For more information on riser notch options and orifices see discussion in OUTLET STRUCTURE CONFIGURATIONS section 71 Santa Margarita Region Hydrology Model Guidance April 2014 AREA Lie ud imm p uy Hm HE Ow 5003 IE sl Flow Splitter 1 Mitigated Facility Name Downstream Connection Both Exits Primary Exaif1 Secondary Exit 2 Tiapezoidal Pond 1 Channel 1 Sec
10. Santa Margarita Region Hydrology Model Guidance April 2014 INTRODUCTION TO SMRHM SMRHM is the Santa Margarita Region Hydrology Model SMRHM is based on the WWHM Western Washington Hydrology Model stormwater modeling software platform WWHM was originally developed for the Washington State Department of Ecology More information about WWHM can be found at www clearcreeksolutions com More information can be found about the Washington State Department of Ecology s stormwater management program and manual at http www ecy wa gov programs wq stormwater manual html Clear Creek Solutions is responsible for SMRHM and the SMRHM guidance documentation This guidance documentation is organized so as to provide the user an example of a standard application using SMRHM described in Quick Start followed by descriptions of the different components and options available in SMRHM The Tips and Tricks section presents some ideas of how to incorporate LID Low Impact Development facilities and practices into the SMRHM analysis Riverside County s Design Handbook for Low Impact Development Best Management Practices September 2011 has the most up to date information regarding BMP standards and should be consulted prior to the start of any SMRHM LID BMP modeling Appendices A and B provide a full list of the HSPF parameter values used in SMRHM Appendix C contains additional guidance and recommendations by the stormwater programs that have sponsor
11. y bubbling pressure y pressure head h z h total hydraulic head elevation head and SE effective saturation Ignoring z elevation head results in h hm matric head Evapotranspiration is an important component of the bioretention facility s hydrologic processes Evapotranspiration removes water from bioretention surface ponding and the soil column during non storm periods The routine will satisfy potential evapo transpiration PET demands in the same sequence as implemented in HSPF 1 Water available from vegetation interception storage 2 Water available from surface ponding 3 Water available from the bioretention soil layers top layer first 178 Appendix E Santa Margarita Region Hydrology Model Guidance June 2013 Water will be removed from vegetation interception storage and surface ponding and the bioretention soil layers starting at the top layer down to the rooting depth at the potential rate Water is taken from the soil layers below the rooting depth based on a percentage factor to be determined Without this factor there will be no way to remove water from below the rooting depth once 1t becomes completely saturated 179
12. 1 00 Version 2013 05 13 Low Flow Threshold for POC i 10 Percent of the 2 Year High Flow Threshold for POC 1 10 year PREDEVELOPED LAND USE Hane DHA 1 Bypass No GronndWater Na Pervious Land Use Acres C D Grass Mod 5 104 10 Pervious Total 10 Impervious Land Use Acres ao Teme ncmo mo Matn ru mia nme gt Pagel 5ec1 y Ati ini Cdi RE mx EC c Engsh us Scroll down the Report screen to see all of the results 3 Santa Margarita Region Hydrology Model Guidance April 2014 8 Save project NE casan Orsan ooo i T 4 Mitigated E POM 1 Trapezoidal Pond 1 Mitipated x F Downstream Connections o EJ f Precipitation Applied to Facility v Evaporation Applied to Facility Facility Dimensions Faclity Bottom Elevation It Bottom Length It Boltom Width It Effective Depth ft Left Side Slope H V Bottom Side Slope HA Right Side Slope HV Top Side Slope HA Infiltration Notch Height 1 RS Hach wiih s Onfice Diameter Height Number in ft Es Af 2 o di af h 4 Pond Volume al Rise Head acf z1n Show Pond Table Open Table H Initial Stage ff Tice Gate Time Series Demand Determine Outlet With Tide Gate Use Tide Gate Tide Gate Elevation tt o DownstreamConnection ow Overflow Elevation if lo lterations jo 5 4 2013 OGAM To save the proje
13. Pond Adjuster pointer from the left to the right 4 Trapezoidal Pond 1 Automatic Pond Adjuster lt 2 10 min 10 min B Predeveloped BE Mitigated Thorough Pond Depth incl 1 ft freeboard 04 ft Pond length to width ratio to 1 Pond Side Slopes 3 to 1 Bottom Length Jf Bottom width ft V alume at riser head Choose Outlet Structure 1 orifice amp rectangular notch Progress Optimize Pond ceepepena Close T i i The pond does not yet have any dimensions Click the Create Pond button to create initial pond dimensions which will be the starting point for Auto Pond s automated optimization process to calculate the pond size and outlet structure dimensions NOTE Depending on the complexity of the project the length of the precipitation record and the computational speed of the computer Auto Pond may take 1 to 15 minutes to run Running Auto Pond automates the following SMRHM processes l the 15 minute Predevelopment scenario runoff is computed for the 30 50 years of record it varies depending on the rain gauge used 2 the Predevelopment runoff flood frequency is calculated based on the partial duration peak flows 3 the range of flows is selected for the flow duration 10 of the 2 year peak to the 10 year peak 4 this flow range is divided into 100 increments and 5 the number of 15 minute Predevelopment flow values that exceed
14. 1 acre C Shrub Moderate 5 10 DMA 3 1 acre C Grass Moderate 5 10 DMA 4 1 acre D Urban Moderate 5 10 Each basin is assigned a different POC point of compliance for the LID analysis 111 Santa Margarita Region Hydrology Model Guidance April 2014 amp MRHIM Fie Edit Vew Hei Summary Report Oe ba At 2am e Os SMEG ooo e lla E FSS m Schematic sE Low Impact I a interfiow Groundwater Precipitation Evaporation Total Runon 2 ESSI sss esl rra 4455 D E Ec E EE ll r NENNEN p Hr h Urt of Inchez Water Balance Chat Clase Unis ol Acie Ft How omata E ae Save xy Loadxy DeselectZe Select By _60 x 1 YA 1 it B A2003 440 PM Click on the Compute LID Base Data button to generate the LID analysis data and summarize the surface runoff interflow groundwater precipitation evaporation and total runoff for all of the basins The results will be shown for each basin in terms of its POC For DMA 1 1 acre of A Grass Moderate slope the distribution of the precipitation 1s Surface runoff 0 242 inches per year Interflow 2 133 inches per year Groundwater 2 089 inches per year Evaporation 11 419 inches per year The sum of the surface runoff interflow groundwater evaporation equals 15 883 inches per year The precipitation at this site equals 15 910 inches per year The difference is because 2 of the gr
15. 168 Appendix D Santa Margarita Region Hydrology Model Guidance June 2013 This page has been intentionally left blank 169 Appendix E Santa Margarita Region Hydrology Model Guidance June 2013 APPENDIX E SMRHM BACKGROUND Effects of Hydromodification Urbanization of a watershed modifies natural watershed and stream processes by altering the terrain modifying the vegetation and soil characteristics introducing pavement and buildings installing drainage and flood control infrastructure and altering the condition of channels through straightening deepening and armoring These changes affect hydrologic characteristics in the watershed rainfall interception infiltration runoff and channel flows and affect the supply and transport of sediment in the MS4 and receiving waters The change in runoff characteristics from a watershed caused by changes in land use conditions is called hydrograph modification or simply hydromodification As the total area of impervious surfaces increases in previously undeveloped areas infiltration of rainfall decreases causing more water to run off the surface as overland flow at a faster rate Storms that previously didn t produce runoff under rural conditions can produce erosive flows The increase in the volume of runoff and the length of time that erosive flows occur ultimately intensify sediment transport causing changes in sediment transport characteristics and the hydraulic geometry width
16. 3 Auto Pond Quick Pond ility Dimension Diagram EE D B f 1 5 4203 412PM The Tools screen is accessed with the Tools tool bar second from the right The two purposes of the Tools screen are 1 To allow users to view SMRHM HSPF PERLND parameter values See Appendix A for a list of the SMRHM HSPF PERLND parameter values 2 To allow users to export time series datasets 106 Santa Margarita Region Hydrology Model Guidance April 2014 SMRHA Example pad B Facility Dimensions Fackty Bottom Elevation It Bottom Length It E ID 1 ELSINORE EVAP P11512 Temecula Valey 1115122 IRRIGATION IN INCHES F 11570 Ilow to Predeveloped Ilow FOCA Mitigated fE 11511000 Trapezodal Pond 1 ALL OUTLETS Mitigated S115 11001 Trapezoidal Pond 1 STAGE Miligated Stat Data End Dale 1374 10 01 0000 200 1 09 30 24 00 Tirmestep Out aw ROWE cee me To export a time series dataset click on the Export Dataset box The list of available time series datasets will be shown The user can select the start and end dates for the data they want to export The time step 15 minute daily monthly yearly can also be specified If the user wants daily monthly or yearly data the user is given the choice of either selecting the maximum minimum or the sum of the 15 minute values Click the Export button 107 Santa Margarita Region Hydrology Model Guidance April 2014 SMRHIA Example
17. 95 9 eo 0090 3800 X 005 X080 95 i5 bo po bo pis 120 7 16 5 880 poso 200 25 120 0997 iz o 500 poso 400 pos zo 0980 jp g poo gso pio 120 poso 19 g440 qw 045 Boo 015 120 poso o o pas po p ha seo 21 5 00 0 070 4000 05 f 20 p 950 25 500 f 070 400 X 005 20 0950 26 q470 X 0055 850 010 120 poso 27 g440 X 0040 Boo 015 120 0 950 28 410 0030 200 25 120 poso 35 420 X 0035 300 X Q 15 2 00 40 poo X025 poo p25 200 143 Appendix A Santa Margarita Region Hydrology Model Guidance June 2013 46 4 20 0 030 350 0 10 3 00 0 995 LZSN Lower Zone Storage Nominal inches INFILT Infiltration inches per hour LSUR Length of surface flow path feet SLSUR Slope of surface flow path feet feet KVARY Variable groundwater recession AGWRC Active Groundwater Recession Constant per day 144 Appendix A Santa Margarita Region Hydrology Model Guidance June 2013 Table 3 SMRHM HSPF Pervious Parameter Values Part II PERLND No NFEXP NFILD DEEPFR BASETP AGWETP PO po bo bos Do 2 Roo Roo poz AX 0 03 00 8 P00 200 poz pos po 4 Roo 200 poz pos X 00 5 poo 200 f 02 pos _ poo 6 1 P00 Roo po AX pos po 3 1 Pe00 OO pon pos _ poo 8 poo Roo poz pos poo 9 poo Roo poz pos poo w go go po pos po 200 200 0 02 0 03 poo ip bo bo pbe bo bo 13 200 200 pos
18. Basin Initial Stage If p l Target io 5 4 2013 302 PM The sand filter is a water quality facility It does not infiltrate surface runoff but 1s used to filter runoff through a medium and send it downstream It can also have one or more surface outlets represented by an outlet structure with a riser and multiple orifices The user must specify the facility dimensions bottom length and width effective depth and sideslopes The hydraulic conductivity of the sand filter and the filter material depth are also SAND FILTER needed to size the sand filter default values are 1 0 inch per hour and 1 5 feet respectively NOTE When using the sand filter element check with Appendix C or the Copermittee with jurisdiction over the project site to determine the EFFECTIVE DEPTH required treatment standard percent BOTTOMLENGTH N of the total runoff volume treated by METER MATERIAE the sand filter 58 Santa Margarita Region Hydrology Model Guidance April 2014 The filter discharge is calculated using the equation Q K I A where Q 1s the discharge in cubic feet per second cfs K equals the hydraulic conductivity inches per hour For sand filters K 1 0 in hr Sand is the default medium If another filtration material 1s used then the design engineer should enter the appropriate K value supported by documentation and approval by the reviewing authority Design of a sand filter requires input of facilit
19. Effective Native Soil Q Vertical Orifice Diameter Vertical Orifice Elevation Total Underdrain Native Soil Native Soil Riser outlet structure option Santa Margarita Region Hydrology Model AER Ow i 8 Be st Bio Swale 1 Mitigated Facility Name Downstream Connection _AFacilty Type Use simple swale Underdrain Used Swele Bottom Elevation A bp Swele Dimensions Flow Through Underdtain acA Swak Length t Swale Bottom width f Freeboard M ili no o ng it Outlet Structure Data Elfeciiva Total Depth H 0 RserQuletStuchse oOo O Bottom slope of Swale 111 Outlet Structure Data Riser Hesght Above Swale surface ft n Riser Diameter in jp Riser Type fi Orifice Diameter Height Mumber in ft Edit Soil Types T 7 E Soi es gt i al ET EX sl KSst Safety Factor 3 o 40 4 amp None C2 i Show Swale Table Open Table Swale Volume al River Head ac It Native Infiltration ho H 5 4 2013 328PM 81 Santa Margarita Region Hydrology Model Guidance April 2014 The input information required for the riser outlet structure is Riser Height above Swale Surface feet depth of surface ponding before the riser 1s overtopped Riser Diameter inches diameter of the stand pipe Riser Type Flat or Notched Notch Type Rectangular V Notch or Sutro For a rectangular notch Notch Height feet distance from the
20. Guidance April 2014 Santa Margarita Region Hydrology Model Ele Edit yew Zoom Help Dark a AER MM AAA ae BESAS developed MA I Ic m eal zu Tarinedbls PRA Mtigated Facility Name i bla Pavement 1 a Outlet i j Outlet 2 Outlet 3 Downsiream Connection Facility Type Oui Pavement ni Overlow Data Pavement i 0 SERRE a Poning Depth Above Paverneri tt on Elfeciwe Total Depth 25 Bottom slopes It ft a Elfectve Volume F actor b Layers for Permeable Pavement Pavement Thickness M Diameter Height Pavenert porosty 0 1 in Sublayer 1 Thickness 1 Underdrain amp o 4 Sublayer 1 porosity 0 1 Sublaper 2 Thickness I Sublayer 2 porosity 0 1 2 lorage Volume at T F ft 367 Infiltration hes See dei ee Measured Infiltration Pate irut hi m Reduction Factor nli lactor fos 4 Show Pavement Table OpenTable Use Wetted Surface Area sidewalt u0 Inaisl Stage h Total Volume Inflirated acit 46139 Total Volume Through Fac ly act Total Volume Through Aize ac ft E261 Save ave Ky Load xy LN A 5 5 2013 S02 AM The permeable pavement dimensions and parameters are Pavement Length ft Roadway length Pavement Bottom Width ft Roadway width Effective Total Depth ft Height from bottom of permeable pavement subgrade to top of pavement plus at least 0 5 feet extra Bottom Slope ft ft Pavement slope
21. Margarita Region Hydrology Model Guidance April 2014 SMRHM Ele Edt yew Hep Summary Report D a Ra di Eas oumHE Ou PS An D2 2 OM P NU 1 Predeveloped A DMA Name Flows To rea in Drainage Management rea Show Only Selected Available Pervious Acres al P ee on r aa CJ Tp ri cs 00 7 AOIRA 0 rima 10 7 is CS a ic os Erre r Dora Tf rima a r iras I gozar 1 rama 1D Cops 6 aw lr sa wien RR r C O Brass Stel 10 20 T CBesVeybo20x gt l 0000000000 VARAS 821 AM After the point of compliance has been added to the DMA the land use basin element will change A small box with a bar chart graphic and a number will be shown in the lower right corner of the element This small POC box identifies this DMA as a point of compliance The number is the POC number e g POC 1 Santa Margarita Region Hydrology Model Guidance April 2014 4 Set up the Mitigated scenario EIN A ES ca ire e Sh fa EMO 9220 M First select the Mitigated scenario tab at the top of the grid Place a land use basin element on the grid to represent the same DMA as selected in the Predevelopment scenario 10 Santa Margarita Region Hydrology Model Guidance April 2014 GMRHIM Aaa Sana 000 A Dx s DA 1 Mitipate
22. Margarita Region Hydrology Model Guidance April 2014 TRAPEZOIDAL POND ELEMENT MESA eee Manir E a al Y 1 Hl M Irapezoidal Pond 1 Mitigated Pe MA Peciptation Applied to Facility M Evaporation Applied to Facity el A F EueummHew5suHuicco c Trapezoid Pond 1 Facility Type Tiapezodal Pond Outlet Outlet 3 Facility Dimensions Fackty Bottom Elevation It Bottom Length It Bottoen width It Effective Depth ft Left Side Slope HAV Bottom Side Slope HV Right Side Slope HV Top Side Slope HA Infiltration Orifice Diameter Height Number in ft lie 1f Hho 4 zip f 2 3 fh affo Pond Volume al Rise Head Lac 11 Show Pond Table Open Table Initial Stage ff Tide Gate Time Series Demand MM Determine Outlet With Tide Gate Lise Tide Gate Tice Gate Elevation t 0 Downstream Connection M Overflow Elevation ff 0 erations In SMRHM there is an individual 0 pond detention basin element for each type of pond and hydrologic control facility The pond element shown above is for a trapezoidal pond This is the most common type of hydrologic control facility A trapezoidal pond has dimensions bottom length and width depth and sideslopes and an outlet structure consisting of a riser and one or more orifices to control the release of runoff from the pond A trapezoidal p
23. Pass 1156 272 B4 Fass 1049 878 83 Pass 563 793 Ez Fass 288 704 79 Fass B22 634 Pass ON 753 577 Fass 040 in 700 517 Pass 10E 5 10E 4 10E 3 T0E 2 10 1 649 482 Pass Percent Time Exceeding Ls 529 454 15 Fass 560 417 Pass 529 389 Pass 502 354 i Pass 464 326 Fass 430 288 Fass 359 265 Pass 365 245 Fass 338 228 Pass 317 207 Fass 284 187 Pass 268 175 Pass 258 162 Fass 241 149 Pass aid 139 i Fass 208 129 Pass 181 116 Pass 184 106 Pass 172 36 Pass 64 BB Fass 152 77 Pass FLOW cfe eee Se EE fs n A E To review the flow duration analysis at the point of compliance select the POC I tab at the bottom and make sure that both the 501 POC 1 Predevelopment flow and 801 POC 1 Developed flow are highlighted 24 Santa Margarita Region Hydrology Model Guidance April 2014 SMRHM AWS Ose SEBEL DOG 501 POC 1 Predeveloped The Pacility PASSED The Facility PASSED Flowi cfs Predev Mit Percentage Pass Fail 1854 1854 100 Fass 15391 1493 93 Pass 14131 i255 eT Pass 1287 1094 ES Pass 1156 372 84 Pass 1048 a78 83 Fass 563 793 BZ Pass BEE 704 79 Pass 522 634 77 Pass 153 577 J Pass 700 517 73 Fass 619 182 74 Pass 599 454 TS Pass 560 417 74 Pass 529 389 13 Pass 502 354 70 Pass 464 326 70 Pass 430 88 66 Pass 355 265 66 Fass 365 245 amp 7 Pass 338 db 67 Pass 317 207 65 Pass 04 107 65 Pass 268 175 65 Fass 256 162 62 Pass 241 i145 gil Fass aga 139 ez Pass 208 129 62 Pass 191 116 60 Fass 184 106 57 P
24. SMRHM the extended detention basin is represented by treatment train connecting a trapezoidal pond or irregular pond element to a gravel trench element to a sand filter element in that order There 1s also the option of creating the extended detention basin s stage storage discharge table outside of SMRHM and inputting it as a SSD Table element SMRHM Ele Edt View Help Summary Report Dc id X Ham MEE ra RACER RA O Schematic Outlet 2 Quick Filter Facility Dimension Diagram River Hesght it Finer Diameter n Fiser Type Fiat EX Motch Type Onfice Diameter Height Number in ft 1 fo fo a 2 n Ho 4 Total Volme Fitzated ac ft 3 if So Total Vols Through Fier act Fiber Stcusge Volume al River Head acA 04 Commercial Toolbox Show Filter Table OpenTable Size Infiltration Basin inaia Staga ft Target hon 4 HE Save xy Load xy H i z S203 250 PM The trapezoidal pond dimensions and parameters to adjust to represent the forebay are discussed on page 46 The irregular pond dimensions and parameters to adjust to represent the forebay are discussed on page 56 The gravel trench dimensions and parameters to adjust to represent the connector trench are discussed on page 59 The sand filter dimensions and parameters to adjust to represent the filter drain are discussed on page 61 The SSD element is discussed on pa
25. SS es LETS O X Bio Swale 1 Mitigated ned DEPT Facility Name BoSwde 1 ssid Outlet 1 Outlet 2 Outlet 3 Downstream Connect Facility Type Bawehenion Sodales W Use simple swale Defeul Swale Underdrain Used Swele Honom Elevation IH Swele Dimensions Ec Flow Through Underdrain acA D Swale Length ft noo Total Outflow act Swale Bottom Width Ft ox Percent Thiough Underdrain Freeboad It oo 1 Facility Dimension Diagram Outlet Structure Data Fa nta infiltration Please insure that you nave maea da arcs a Las La Lind ow pJ IE Sod Layer 1 GRAVEL Sod Layer 2 GRAVEL v Orifice Diameter Height Sed Layer 3 Ci y Number in a ft of 1 o fo KS ioi Factor 3 fo Ho f Mane Show Swale Table OpenTable Svale Volume at River Head ac It Native Infiltration no 5 4 2013 31 33PM gt al There is a simple swale option It 1s computationally much faster than the standard bioretention Before using the simple swale option read the note on the screen and the information below to understand the limitations of the simple swale The standard bioretention routine uses HSPF Special Actions to check the available amended soil storage and compares 1t with the stormwater runoff inflow rate Because of the check done by HSPF Special Actions simulations using bioretention take much longer than simulations not using biorete
26. Standard Drawing Concrete CB 110 or similar forebay Inlet PL i Maintenance access Either CB 110 overflow PLAN outlet or emergency aa spillway may be used Pipe inlet 7 at embankment Concrete impact wall with full height weir s Water surface da 5 0 max depth I ANTE Gf ALI LPAI AE LP LP LEAL ARAS AE I SIL LP LE AP LE Lif LP Ll RRR RRR WORRY EA na RES a or Cott EEO NINN NNN ONG NG PLL 1 1 1 I e I I a LAR LR I a RA gt RRA Figure courtesy of Riverside County Flood Control and Water Conservation District An infiltration basin allows stormwater runoff to enter the basin above ground and then infiltrate through the bottom of the basin into the native soil beneath the basin Overflow is controlled by an overflow outlet For the purpose of flow control the discharge from the overflow outlet should not exceed the predevelopment discharge from the project site for the flow duration range specified by the Copermittee with jurisdiction over the project site In SMRHM the infiltration basin is represented by the trapezoidal or irregular shaped pond element 119 Santa Margarita Region Hydrology Model Guidance April 2014 Santa Margarita Region Hydrology Model Fie Edit View Zoom Help uE LERTAS E EIE MEET TOT Facility Name Facility Type Outlet 1 Outlet 2 Outlet 3 Downstream Connections E JE E i Precoitation Applied to Faclity v Evaporation Applied to Facility Facil
27. Swale Bottom Elevation ft Orifice Diameter in e Jo Swale Dimensions Flow Through Underdesn acA 4563 Total Quifow lact 111 778 Percent Through Underdrain 404 Facility Dimension Diagram Riser OutetStuctwe ef Outlet Structure Data Faser Hexchi Above Swale surface it ns Riser Diameter inj a H Paete frig Maternal Layers for Swale Notch Type Layer Layer Laper3 0 280 2000 pw Pest mended 5 inh Orfice Diameter Height ft A Number in 1 n 4b 4 Edit Soil Types 2 p h KSal Safety Factor 3 np a CE 4 amp None C2 Ca Show Swale Table OpenTable H Swale Volinee al Riser Head acA Das GRAVEL Native Infiltration MO 5 5 2013 EJI PM The bioretention dimensions and parameters to adjust to represent the bioretention standard design are discussed on page 81 The Riverside County Design Handbook for Low Impact Development Best Management Practices specifies the following criteria for bioretention vertical sideslopes Minimum width 2 ft Sideslope 0 to 1 Maximum ponding depth 0 5 ft Mulch top layer 2 to 3 inches deep above amended soil layer Minimum amended soil layer depth 1 5 ft Maximum amended soil layer depth 3 ft Maximum amended soil porosity 0 30 Maximum gravel layer 1 ft below amended soil layer Gravel layer porosity 0 40 Minimum underdrain diameter 0 5 ft No infiltration to native soil 131 Santa Margarita Region H
28. Western Washington The latest 2012 edition in 5 volumes is on the Web at http www ecy wa gov programs wq stormwater manual html Design recommendations from this manual were the basis for many features of the WWHM that have been carried over into SMRHM Portions of Volume 3 Hydrology that may be of interest to project designers include o Pages 3 2 through 3 18 illustrate several types of roof downspout controls simple pre engineered designs for infiltrating and or dispersing runoff from roof areas in order to reduce runoff volume and or increase potential groundwater recharge o Pages 3 50 to 3 63 discuss outlet control structures their maintenance and source equations modeled into WWHM and SMRHM 166 Appendix C Santa Margarita Region Hydrology Model Guidance June 2013 e Pages 3 75 to 3 93 regarding Infiltration Reduction Factor Urban Storm Drain Criteria Manual by the Denver Urban Drainage and Flood Control District is on the Web at http www udfcd org downloads down critmanual htm Volume 3 covers design of stormwater runoff treatment measures including extended detention basins on pages S 66 through S 77 and structural details shown on pages SD 1 to SD 16 Although these designs are not presented for hydromodification management control the perforated plate design concept allows fine tuning of drawdown times and is adaptable for use in flow duration facilities 167 Appendix D Santa Margarita Region Hydrology Mod
29. and selecting and then left clicking on the Connect To Element option By doing so SMRHM extends a line from the upstream element to wherever the user wants to connect that element 87 Santa Margarita Region Hydrology Model Guidance April 2014 Santa Margarita Region Hydrology Model Fle Edit View Helo Summary Report naaa Sabb oc Ox si DMA 1 Mitigated Deigen Bypass lor POC ael S