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HomeMy WebLinkAbout4545 W 141st Street Drainage TIR 11-04-19 Stormwater Technical Information Report For: Proposed Single Family Residence 4545 West 141st Street Carmel, Indiana 46074 Job #: 19-05-01 Date: 11 /04/2019 Prepared for: Mr. Phil Pegram 14371 Chariots Whisper Drive Carmel, IN 46074 Prepared by: Red Barn Engineering Company Chris Hinkle, PE 317 -677-6797 Chris@RedBarnEngineeringCo.com TABLE OF CONTENTS Section I: Project Description A. Project Title B. Project Description C. Project Parameters D. Design Method and Criteria E. Summary of Proposed Flow rates F. References Section II: Appendix A. Soils Map B. FEMA Map C. Offsite Runoff Calculations D. Existing Conditions Exhibit E. Proposed Conditions Exhibit F. Runoff Calculations Including: 1. Basin C Factor Calculations 2. Basin Release Rates 3. Water Quality Calculations Page 1 11/04/19 Section I: Project Description A. Project Title New Single Family Residence B. Project Description This project is located at 14371 Charles Whisper Drive in Clay Township, Hamilton County, Carmel, Indiana. The site is approximately 7.0 acres with the proposed disturbed area being approximately 1.9 acres. The site is currently a combination of wooded and meadow areas. The proposed development of the site will consist of the construction of a single family residence along with an asphalt drive connection to 141st Street. A majority of the proposed runoff from the disturbed area will be routed through a new drainage system and to the proposed dry detention basin located to the north of the main residence. C. Project Parameters Zoning This site is currently zoned S-1 (Single Family Residential). The S-1 zoning designation permits single family residential development. The existing land uses and zoning adjacent to the site are as follows: North: Residential, S-1 West: Residential, S-1 South: Residential, S-1 East: Residential, S-1 Soil Type Soil maps from the United States Department of Agriculture, Soil Conservation Service, identify the site as having Brookston soils (Br) 0 to 2 percent slopes, Miami soils (MmA) 0 to 2 percent slopes, and Shoals silt loam (Sh), 0 to 2 percent slopes. There are also Urban complexes of Crosby and Miami located on the site. The Brookston and Miami soils are a part of Hydrologic Soil Group B and the Shoals soils are a part of Hydrologic Soil Group C. Watershed The site is located within the Little Eagle Creek – Woodruff Branch watershed. The 14-digit Hydrologic Unit Code is 05120201120070. The site is located in Zone X per Flood Map Panel 041 of the Flood Insurance Rate Map for Hamilton County, (FIRM Number 18097C0041 F), dated April 19, 2016. D. Design Methods and Criteria The stormwater management calculations have been performed based on the criteria available from the City of Carmel Stormwater Technical Standards Manual. The intent of the stormwater design is to restrict the proposed runoff rates to ensure they are in accordance with the City of Carmel Technical Standards Manual. All calculations referred to in this report can be found in the Appendix of this report. The stormwater modeling program HydroCAD has been used to calculate the flows from the offsite watershed through the existing creek. The program uses the TR-20 method along with the Type 2 rainfall distribution curve for calculating total runoff volumes for Page 2 11/04/19 each storm event. Factors involved in the use of this method are the area of the watershed, the runoff curve number (CN), the time of concentration, and the associated rainfall intensity for the selected rainfall event. The Rational Method has been used to generate runoff from the developed watershed and for the proposed stormwater detention calculations. Factors involved in the use of this method are the area of the watershed, the runoff coefficient, the time of concentration, and the associated rainfall intensity for the selected rainfall event. The runoff coefficient is estimated based on the proposed land use. Offsite Runoff: As a part of the construction of the driveway to the site, a new 38”x57” CMP arch culvert pipe has been placed within the unnamed creek which bisects the property. The City of Carmel has requested this culvert pipe be examined to ensure it will allow the flow from the upstream watershed to pass through the site without negatively affecting the flow through the creek. The creek is not a regulated drain as determined by the Hamilton County Surveyor’s Office. The approximate offsite area contributing to the creek is 239 acres. This area consists of multiple residential developments, some single-family homes, farm fields, meadows, and woods. There are also approximately 9 acres of ponds in the basin. Although these ponds all are providing detention throughout the watershed, all runoff calculations assume these ponds aren’t functioning as the exact level of detention couldn’t be determined. Based on the offsite area, time of concentration, and curve number for the offsite watershed, the proposed flows from the basin are as follows: 2yr. = 49.9 cfs 10yr. = 129.4 cfs 100yr. = 355.5 cfs The existing culvert pipe has the capacity to convey approximately 66 cfs. The invert of culvert pipe is at 863.12. Storm events greater than the 2-year storm will sheet flow over top of the proposed driveway. A 160’ section of the drive will be at an elevation of 866.75 with a 390’ portion of the drive at 867.25. These sections of the proposed driveway will serve as spillway for the creek. The approximate 100-year elevations of the creek over the driveway are as follows: 2yr. = 866.33’ 10yr. = 866.97’ 100yr. = 867.25’ Therefore, no negative impacts are anticipated due to the installation of the culvert pipe or the proposed driveway. Pre-Developed Conditions: Existing storm water runoff from the project area generally sheet drains to the creek in the center of the property. There are a couple of low areas which direct the runoff to the creek. The creek then empties out into a private pond located to the west of the property. Post-Developed Conditions: The proposed development of the site will consist of the construction of a single family resi- dence on the site. A new dry detention basin will be constructed to the north of the resi- dence. The runoff form the proposed improvements will be collected in foundation drains, roof drains, and swales and routed to the proposed basin. Page 3 11/04/19 The goal of the proposed management plan is to reduce the overall runoff from the site in accordance with the guidelines set forth in the City of Carmel Stormwater Technical Stand- ards Manual. The proposed watershed for the development encompasses 3.76 acres. The proposed 10-year runoff will be detained to the 0.1 cfs/acre (0.37 cfs) rate and the proposed 100-year runoff will be detained to the 0.3 cfs/acre (1.13 cfs) rate. Runoff from the proposed site will be collected in the stormwater collection systems throughout the site and routed to the proposed basin. The proposed release rate from the basin will be controlled with a 6” diameter orifice located within a storm sewer structure set at the western edge of the proposed basin. The detention calculation requires a 4” diameter orifice, but as noted in the City of Carmel Stormwater Technical Standards Manual, the min- imum size of the orifice is 6”. Runoff from the pond will be discharged into an existing 12” CMP that runs under the proposed driveway and into the existing creek. A 1” diameter outlet will provide water quality for the proposed basin. This orifice will be set at the ground elevation (865.0) and will be collected into a proposed storm sewer structure before being routed to the creek. In addition to the two orifices, a 30’ wide spillway will be constructed to allow the pond to overtop and release 1.25 x the proposed 100-year flow from the project site. E. Summary of Proposed Flowrates: Post-Developed Runoff (with 4” outlet pipe design): 100yr. = 0.30 cfs The proposed wet pond has been designed in accordance with the City of Carmel Storm- water Technical Standards Manual for both water quantity and water quality. Therefore, there is no negative impact expected from this proposed project. F. References 1. Herpicc Stormwater Drainage Manual – Revised July 1995. 2. Hamilton County Soil Survey – National Resources Conservation Service. 3. City of Carmel Storm water Design and Construction Manual (Updated 2017). 4. National Flood Insurance Program - Federal Emergency Management Agency. Page 4 11/04/19 SECTION II: APPENDIX Page 5 11/04/19 Soil Map—Hamilton County, Indiana Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 11/4/2019 Page 1 of 3442679044268304426870442691044269504426990442703044270704427110442679044268304426870442691044269504426990442703044270704427110564930564970565010565050565090565130565170 564930 564970 565010 565050 565090 565130 565170 39° 59' 30'' N 86° 14' 22'' W39° 59' 30'' N86° 14' 11'' W39° 59' 19'' N 86° 14' 22'' W39° 59' 19'' N 86° 14' 11'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 16N WGS84 0 50 100 200 300 Feet 0 20 40 80 120 Meters Map Scale: 1:1,650 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. Page 6 11/04/19 MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:15,800. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Hamilton County, Indiana Survey Area Data: Version 20, Sep 16, 2019 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 1, 2018—Sep 30, 2018 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Soil Map—Hamilton County, Indiana Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 11/4/2019 Page 2 of 3Page 711/04/19 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI Br Brookston silty clay loam, 0 to 2 percent slopes 0.7 9.1% MmA Miami silt loam, 0 to 2 percent slopes 3.8 48.2% Sh Shoals silt loam, 0 to 2 percent slopes, frequently flooded, brief duration 1.2 14.8% YclA Crosby silt loam, fine-loamy subsoil-Urban land complex, 0 to 2 percent slopes 1.3 16.0% YmsB2 Miami silt loam-Urban land complex, 2 to 6 percent slopes, eroded 0.9 11.9% Totals for Area of Interest 7.8 100.0% Soil Map—Hamilton County, Indiana Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 11/4/2019 Page 3 of 3 Page 8 11/04/19 AREA OF MINIMAL FLOOD HAZARD Zone X Zone AE FLOODWAY Zone AE FLOODWAY Zone AE T18N R2E S24 CITY OF CARMEL180081 %,K USGS The National Map: Orthoimagery. Data refreshed April, 2019. National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250Feet Ü86°14'31.80"W 39°59'42.97"N 86°13'54.35"W 39°59'15.40"N SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOODHAZARD AREAS Without Base Flood Elevation (BFE)Zone A, V, A99With BFE or Depth Zone AE, AO, AH, VE, AR Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areasof 1% annual chance flood with averagedepth less than one foot or with drainageareas of less than one square mile Zone X Future Conditions 1% AnnualChance Flood Hazard Zone XArea with Reduced Flood Risk due toLevee. See Notes.Zone X Area with Flood Risk due to Levee Zone D NO SCREEN Area of Minimal Flood Hazard Zone X Area of Undetermined Flood Hazard Zone D Channel, Culvert, or Storm SewerLevee, Dike, or Floodwall Cross Sections with 1% Annual Chance17.5 Water Surface ElevationCoastal Transect Coastal Transect BaselineProfile BaselineHydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of StudyJurisdiction Boundary Digital Data Available No Digital Data Available Unmapped This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. The basemap shown complies with FEMA's basemap accuracy standards The flood hazard information is derived directly from theauthoritative NFHL web services provided by FEMA. This mapwas exported on 11/5/2019 at 12:21:26 PM and does notreflect changes or amendments subsequent to this date andtime. The NFHL and effective information may change orbecome superseded by new data over time. This map image is void if the one or more of the following mapelements do not appear: basemap imagery, flood zone labels,legend, scale bar, map creation date, community identifiers,FIRM panel number, and FIRM effective date. Map images forunmapped and unmodernized areas cannot be used forregulatory purposes. Legend OTHER AREAS OFFLOOD HAZARD OTHER AREAS GENERALSTRUCTURES OTHERFEATURES MAP PANELS 8 1:6,000 B 20.2 The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location.Page 911/04/19 ..\..\..\Desktop\SEA Group Small Projects\19-05-01 4545 W 141st Street Carmel\Images\Cover.PNG\\edge\SEADATA1\Residential\2018\4513-Pegram141stSTtreeLocations\TOPO.tiffTc ROUTETc ROUTE19-05-01Sheet NumberProject NumberCertified ByDate: 11/04/20191-800-382-5544Red Barn Engineering Company, LLC Civil Engineering Consulting Services 317.677.6797 www.RedBarnEngineeringCo.com Chris@RedBarnEngineeringCo.com NEW RESIDENTIAL CONSTRUCTION 4545 West 141st Street CARMEL, INDIANA 46074 Prepared For: Mr. Phil Pegram 14371 Chariots Whisper Drive Carmel, Indiana 46074 317.506.5155EXHIBITOFFSITE DRAINAGE BASIN 1 inch = 200 ft.OFFSITE DRAINAGE BASINScale: 1" = 200'0 100 200( IN FEET)Page 1011/04/19 Indiana LTAP Stormwater Drainage Manual - Revised February 2008 Chapter 3 - 19 Table 3.3.3 Runoff Curve Numbers for Urban Areas (USDA, 1986) ────────────────────────────────────────────── Cover Type and Curve Numbers for Hydrologic Condition Hydrologic Soil Group A B C D ________________________________________________________________________________________ Undeveloped Areas Cultivated Land Without conservation treatment 72 81 88 91 With conservation treatment 62 71 78 81 Pasture or range land Poor condition 68 79 86 89 Good condition 39 61 74 80 Meadow Good condition 30 58 71 78 Wood or forest land Thin stand, poor cover, no mulch 45 66 77 83 Good cover 25 55 70 77 Fully developed urban areas (with established vegetation) Open space (lawns, parks, golf courses, cemeteries) Poor condition (grass cover < 50%) 68 79 86 89 Fair condition (grass cover 50% to 75%) 49 69 79 84 Good condition (grass cover > 75%) 39 61 74 80 Impervious areas: Paved parking lots, roofs, driveways, etc. (excluding right-of-way) 98 98 98 98 Streets and roads: Paved : curb and storm sewers (excluding right-of-way) 98 98 98 98 Gravel 76 85 89 91 Dirt 72 82 87 89 Urban Districts Commercial and business (85% impervious) 89 92 94 95 Industrial (72% impervious) 81 88 91 93 Residential 1/8 acre or less, townhouses (65% impervious) 77 85 90 92 1/4 acre (38% impervious) 61 75 83 87 1/3 acre (30% impervious) 57 72 81 86 1/2 acre (25% impervious) 54 70 80 85 1 acre (20% impervious) 51 68 79 84 2 acre 46 65 77 82 Developing Urban Areas Page 11 11/04/19 Indiana LTAP Stormwater Drainage Manual - Revised February 2008 Chapter 3 - 21 Table 3.3.4 Runoff Curve Numbers for Agricultural Lands (USDA, 1986) Cover Type and Curve Numbers for Hydrologic Condition Hydrologic Soil Group A B C D Pasture, grassland, or range with continuous forage for grazing Poor 68 79 86 89 Fair 49 69 79 84 Good 39 61 74 80 Meadow with continuous grass, protected from grazing and generally mowed for hay 30 58 71 78 Brush/brush-weed-grass mixture with brush being the major element Poor 48 67 77 83 Fair 35 56 70 77 Good 30 48 65 73 Woods and grass combination (orchard or tree farm) Poor 57 73 82 86 Fair 43 65 76 82 Good 32 58 72 79 Woods Poor 45 66 77 83 Fair 36 60 73 79 Good 30 55 70 77 Farmsteads 59 74 82 86 The curve number method may also be used in determining the time distribution of the runoff. In this manual, the CN method is used in conjunction with the synthetic dimensionless and triangular unit hydrograph methods to determine the storm hydrograph. The procedure used in this operation is outlined below. 1. Determine the basin curve number. 2. Given the rainfall depth and storm duration, determine the time distribution of the rainfall. This distribution can be the SCS Type II or Huff Distributions discussed in Page 12 11/04/19 Table 3.3.2 Hydrologic Soil Groups For Indiana Soils (Shown in parentheses after the soil classification) Notes: 1. Two hydrologic soil groups shown together, such as B/C, indicate the drained/undrained conditions. 2. Any modifiers shown, e.g., bedrock substratum, refer to a specific soil series phase found in the soil map legend. Chapter 3 - 17 Abscota (A) Ackerman (A/D) Ade (A) Adrian (A/D) Alford (B) Algansee (B) Algiers (C/D) Alida (B) Allison (B) Alvin (B) Ambraw (B/D) Andres (B) Aptakisic (B) Armiesburg (B) Ashkum (B/D) Atkins (D) Aubbeenaubbee (B) Ava (C) Avonburg (D) Ayr (B) Ayrmount (B) Ayrshire (C) Banlic (C) Barce (B) Barry (B/D) Bartle (D) Battleground (B) Baxter (B) Beanblossom (B) Beasley (C) Beaucoup (B/D) Beckville (B) Bedford (C) Beecher (C) Belknap (C) Belleville (B/D) Belmore (B) Berks (C) Bethesda (C) Bewleyville (B) Billett (B) Birds (C/D) Birkbeck (B) Bloomfield (A) Blount (C) Bobtown (C) Bonnell (C) Bonnie (C/D) Bono (D) Booker (D) Boonesboro (B) Boots (A/D) Bourbon (B) Bowes (B) Boyer (B) Brady (B) Branch (B) Brems (A) Brenton (B) Bromer (C) Bronson (B) Brookston (B/D) Bruno (A) Bryce (D) Burside (B) Cadiz(B) Camden (B) Cana (C) Caneyville (C) Carlisle (A/D) Carmel (C) Carmi (B) Casco (B) Catlin (B) Celina (C) Ceresco (B) Chagrin (B) Chalmers (B/D) Chatterton (A) Cheektowaga (D) Chelsea (A) Chetwynd (B) Cincinnati (C) Clarence (D) Cleremont (D) Clyde (B/D) Cobbsford (D) Coesse (C/D) Cohoctah (B/D) Coloma (A) Colyer (D) Comfrey (B/D) Conotton (B) Conover (C) Conrad (A/D) Coolville (C) Corwin (B) Cory (C) Corydon (D) Coupee (B) Craigmile (B/D) Crane (B) Crawleyville (B) Crider (B) Crosby (C) Crosier (C) Cuba (B) Cyclone (B/D) Dana (B) Darroch (B) Darroch, bedrock subsratum (C) Dearborn (B) Del Rey (C) Deputy (C) Derinda (C) Desker (A) Dickinson (B) Digby (B) Door (B) Dowagiac (B) Driftwood (C/D) Drummer (B/D) Du Page (B) Dubois (C) Dunning (D) Ebal (B) Eden (C) Edenton C) Edwards (B/D) Eel (B) Eldean (B) Elkinsville (B) Elliott (C) Elston (B) Evansville (B/D) Fabius (B) Fairmount (D) Fairpoint (C) Farmington (C) Faxon (B/D) Fincastle (C) Flanagan (B) Foresman (B) Fox (B) Frederick (B) Free (B/D) Fulton (D) Genesee (B) Gessie (B) Gilboa (B) Gilford (B/D) Gilford, stratified substratum (D) Gilpin (C) Ginat (D) Glenhall (B) Glynwood (C) Gosport (C) Granby (A/D) Gravelton (B/D) Grayford (B) Griswold (B) Grovecity (B) Gudgel (C) Guthrie (D) Hagerstown (C) Haney (B) Hanna (B) Harpster (B/D) Haskins (C) Haubstadt (C) Haymond (B) Hennepin (B) Henshaw (C) Hickory (C) High Gap (C) Hillsdale (B) Holton (C) Homer (B) Hononegah (A) Hoopeston (B) Hoosierville (C) Hosmer (C) Houghton (A/D) Hoytville (C/D) Huntington (B) Huntsville (B) Iona (B) Ipava (B) Iroquois (B/D) Iva (C) Jasper (B) Jennings (C) Johnsburg (D) Jules (B) Junius (C) Kalamazoo (B) Kendallville (B) Kentland (A/D) Kerston (A/D) Kibbie (B) Kings (D) Kokomo (B/D) Kosciusko (B) Kurtz (C) Lafayette (B) La Hogue (B) Landes (B) Lash (B) Laramie (B) Lawrence (C) Lenawee (B/D) Lindside (C) Linkville (C) Linwood (A/D) Lisbon (B) Lobdell (B) Lomax (B) Longlois (B) Losantville (C) Lucas (D) Lydick (B) Lyles (B/D) Mahalasville (B/D) Maplehille (C) Marker (B) Markham (C) Markland (C) Markton (C) Martinsville (B) Martisco (B/D) Maumee (A/D) McGary (C) Medora (B) Medway (B) Mellott (B) Mermill (B/D) Metamora (B) Metea (B) Miami (B) Miamian (C) Middlebury (B) Milford (B/D) Millbrook (B) Millgrove (B/D) Page 13 11/04/19 Table 3.3.2 Hydrologic Soil Groups For Indiana Soils (Shown in parentheses after the soil classification) Notes: 1. Two hydrologic soil groups shown together, such as B/C, indicate the drained/undrained conditions. 2. Any modifiers shown, e.g., bedrock substratum, refer to a specific soil series phase found in the soil map legend. Chapter 3 - 18 Millsdale (B/D) Milton (C) Monitor (C) Montgomery (D) Montmorenci (B) Morley (C) Morocco (B) Moundhaven (A) Muldavia (B) Mulvey (B) Mundelein (B) Muren (B) Muskego (A/D) Muskingum (C) Mussey (B/D) Napoleon (A/D) Nappanee (D) Negley (B) Nesius (A) Newark (C) Newglarus (B) Newton (A/D) Nicholson (C) Nineveh (B) Nolin (B) Oakville (A) Ockley (B) Octagon (B) Odell (B) Oldenburg (B) Onarga (B) Ormas (B) Orrville (C) Oshtemo (B) Otwell (C) Ouiateno (A) Owosso (B) Palms (A/D) Papineau (C) Parke (B) Parr (B) Pate (C) Patton (B/D) Pekin (C) Pella (B/D) Peoga (C) Peotone (B/D) Petrolia (B/D) Pewamo (C/D) Philo (B) Piankeshaw (B) Pike (B) Pinevillage (B) Pinhook (B/D) Piopolis (C/D) Pipestone (B) Plainfield (A) Plano (B) Pope (B) Princeton (A) Prochaska (A/D) Proctor (B) Quinn (B/D) Ragsdale (B/D) Ragsdale, overwash (B) Rahm (C) Rainsville (B) Randolph (C) Rarden (C) Raub (C) Rawson (B) Reddick (B/D) Reesville (C) Rensselaer (B/D) Rensselaer, nonstratified substratum (C) Richardsville (B) Riddles (B) Ridgeville (B) Rimer (C) Riverdale (A) Roby (C) Rockcastle (D) Rockfield (B) Rockton (B) Rodman (A) Ross (B) Rossmoyne (C) Ruark (B/D) Rush (B) Russell (B) Ryker (B) Sable (B/D) Saranac (C/D) Saranac, gravelly substratum (C) Saugatuck (C) Sawabash (B) Sciotoville (C) Seafield (B) Sebewa (B/D) Selfridge (B) Selma (B/D) Seward (B) Shadeland (C) Shakamak (C) Shipshe (B) Shoals (C) Sidell (B) Simonin (B) Sisson (B) Skelton (B) Sleeth (C) Sloan (B/D) Sparta (A) Spinks (A) St. Charles (B) St. Clair (D) Starks (C) Steff (C) Stendal (C) Stockland (B) Stonelick (B) Stoy (C) Strawn (B) Strole (C) Suman (B/D) Sumava (B) Sunbury (B) Swanwick (D) Switzerland (B) Swygert (C) Sylvan (B) Symerton (B) Taftown (B) Taggart (C) Tama (B) Tawas (A/D) Tecumseh (B) Tedrow (B) Thackery (B) Throckmorton (B) Tice (B) Tilsit (C) Tippecanoe (B) Toledo (D) Toronto (C) Toto (B/D) Tracy (B) Trappist (C) Treaty (B/D) Trevlac (B) Troxel (B) Tuscola (B) Tyner (A) Uniontown (B) Varna (C) Vigo (D) Vincennes (C/D) Volinia (B) Wabash (D) Wakeland (C) Wallkill (C/D) Warners (C/D) Warsaw (B) Wasepi (B) Washtenaw (C/D) Watseka (B) Waupecan (B) Wauseon (B/D) Wawasee (B) Waynetown (C) Wea (B) Weikert (C/D) Weinbach (C) Weisburg (C) Wellston (B) Westland (B/D) Wheeling (B) Whitaker (C) Whitson (D) Wilbur (B) Wilhite (C/D) Willette (A/D) Williamsport (C) Williamstown (C) Wingate (B) Wirt (B) Wolcott (B/D) Woodmere (B) Woolper (C) Wynn (B) Xenia (B) Zaborosky (B) Zadog (A/D) Zanesville (C) Zipp (D) Page 14 11/04/19 WATERSHED TOTAL TOTAL Roof (sf)Pond (sf)1/2 acre lots Pavement (sf)Lawn (sf)Light Woods Bare Earth Woods (sf) AREA (ac)AREA (sf)WEIGHTED WEIGHTED Runoff Coefficient 0.90 0.90 0.35 0.85 0.20 0.25 0.55 0.20 RUNOFF C RUNOFF CN Curve Number 98.00 98.00 73.92 98.00 67.15 70.70 68.71 62.63 Overall Creek Basin 239.01 10411230 0 426890 2597725 191025 3263885 2109190 703060 1119455 0.31 71.01 Existing Basin 3.76 163750 0 0 0 131000 24563 0 8188 0.21 67.45 Proposed Basin 3.76 163750 6050 10900 11330 102720 24563 0 8188 0.32 72.78 WATERSHED AREA (ac)Hydrologic % of Total Group Area Soil Map Basin 8.20 C 2.92 280.9 0.90 B 0.32 28.90 B 10.29 8.60 C 3.06 9.80 3.49 50.10 C 17.84 111.90 C 39.84 62.50 B 22.25 92.30 32.86 178.80 63.65 WATERSHED Weighted Group B Group C CN Value Weighted Percentage 32.86 63.65 61 74 67.1 66 77 70.7 58 78 68.7 55 70 62.6 70 80 73.9 98 98 98.0 98 98 98.0 DEVELOPED SITE DRAINAGE BASIN C FACTOR CALCULATIONS Brookston DRAINAGE BASIN SOIL TYPE BREAKDOWN Soil Type Gessie Group B Group C SOIL CURVE NUMBER CALCULATIONS Cover Type and HERPICC CN Hydraulic Condition Miami Shoals Water Urban - Brookston Urban - Miami Urban - Crosby Pavement Lawn Light Woods Field Woods 1/2 acre lots Pond Page 15 11/04/19 Project: 4545 W. 141st Street Residence Location: Carmel, IN Date: 11/4/2019 Check One: BASIN NAME :Overall Offsite Basin Sheet Flow Segment ID A-B Surface description (table 3-1)..........................Grass Smooth Manning's roughness coefficient, n (table 3-1)….0.24 0.011 Flow length, L (total L<=300f..........................ft.100 Two-yr 24hr rainfall, p2...................................in.2.66 Land slope, s..............................................ft/ft 0.02 Tt = 0.0043 (nL)0.8 Computed T......................hr.0.261 0.000 S0.4 Shallow Concentrated Flow Segment ID B-C C-D Surface description (paved or unpaved)...............unpaved unpaved Flow length, L................................................ft.4000 1615 Watercourse slope, s...................................ft/ft 0.01 0.01 Average velocity, V (figure 3-1)......................ft/s 1.61 1.61 Tt = L/(3600 V) Computed Tt…………..……...hr.0.689 0.278 Channel Flow Segment ID Cross sectional flow area, a............................ft2 Wetted perimeter, PW....................................ft. Hydraulic radius, r=a/PW Compute……..…....ft. Channel slope,s.........................................ft/ft Manning's roughness coefficeint,n………...……. V =(1.49 r2/3 s1/2)/n Compute………………...ft/s Flow length, L ..............................................ft. Tt = L/(3600 V) Computed Tt………..………...hr. Pipe Flow Segment ID Velocity......................................................ft/s Length..........................................................ft. Tt=L/(3600v) Computed Tt…………..……....hr. Watershed or subarea Tc or Tt..................hr.1.228 Watershed or subarea Tc or Tt...............min.73.7 Time of Concentration (Tc) Worksheet Pre-Development Post-Development Page 16 11/04/19 3PCB Proposed Driveway 3S Offsite Routing Diagram for Drainage Calculations Prepared by Windows User, Printed 11/4/2019 HydroCAD® 10.00-24 s/n 08312 © 2018 HydroCAD Software Solutions LLC Subcat Reach Pond Link Page 17 11/04/19 Type II 24-hr 100 - year Rainfall=6.46"Drainage Calculations Printed 11/4/2019Prepared by Windows User HydroCAD® 10.00-24 s/n 08312 © 2018 HydroCAD Software Solutions LLC Summary for Subcatchment 3S: Offsite Runoff = 355.53 cfs @ 12.83 hrs, Volume= 65.202 af, Depth= 3.27" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 - year Rainfall=6.46" Area (ac) CN Description * 239.010 71.0 239.010 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 73.7 Direct Entry, Page 18 11/04/19 Type II 24-hr 100 - year Rainfall=6.46"Drainage Calculations Printed 11/4/2019Prepared by Windows User HydroCAD® 10.00-24 s/n 08312 © 2018 HydroCAD Software Solutions LLC Events for Subcatchment 3S: Offsite Event Rainfall (inches) Runoff (cfs) Volume (acre-feet) Depth (inches) 2 - year 2.66 49.92 11.414 0.57 10 - year 3.83 129.36 25.477 1.28 100 - year 6.46 355.53 65.202 3.27 Page 19 11/04/19 Type II 24-hr 100 - year Rainfall=6.46"Drainage Calculations Printed 11/4/2019Prepared by Windows User HydroCAD® 10.00-24 s/n 08312 © 2018 HydroCAD Software Solutions LLC Summary for Subcatchment 3S: Offsite Runoff = 355.53 cfs @ 12.83 hrs, Volume= 65.202 af, Depth= 3.27" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Type II 24-hr 100 - year Rainfall=6.46" Area (ac) CN Description * 239.010 71.0 239.010 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 73.7 Direct Entry, Page 20 11/04/19 Type II 24-hr 100 - year Rainfall=6.46"Drainage Calculations Printed 11/4/2019Prepared by Windows User HydroCAD® 10.00-24 s/n 08312 © 2018 HydroCAD Software Solutions LLC Events for Subcatchment 3S: Offsite Event Rainfall (inches) Runoff (cfs) Volume (acre-feet) Depth (inches) 2 - year 2.66 49.92 11.414 0.57 10 - year 3.83 129.36 25.477 1.28 100 - year 6.46 355.53 65.202 3.27 Page 21 11/04/19 Type II 24-hr 2 - year Rainfall=2.66"Drainage Calculations Printed 11/4/2019Prepared by Windows User Page 2HydroCAD® 10.00-24 s/n 08312 © 2018 HydroCAD Software Solutions LLC Summary for Pond 3P: Proposed Driveway [57] Hint: Peaked at 866.33' (Flood elevation advised) Inflow Area = 239.010 ac, 0.00% Impervious, Inflow Depth = 0.57" for 2 - year event Inflow = 49.92 cfs @ 12.90 hrs, Volume= 11.414 af Outflow = 49.92 cfs @ 12.90 hrs, Volume= 11.414 af, Atten= 0%, Lag= 0.0 min Primary = 49.92 cfs @ 12.90 hrs, Volume= 11.414 af Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Peak Elev= 866.33' @ 12.90 hrs Device Routing Invert Outlet Devices #1 Primary 863.12'57.0" W x 38.0" H, R=28.9"/88.3" Pipe Arch CMP_Arch_1/2 57x38 L= 30.0' CMP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 863.12' / 863.08' S= 0.0013 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 11.89 sf #2 Primary 866.75'Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 0.50 Width (feet) 160.00 390.00 Primary OutFlow Max=49.92 cfs @ 12.90 hrs HW=866.33' (Free Discharge) 1=CMP_Arch_1/2 57x38 (Barrel Controls 49.92 cfs @ 4.97 fps) 2=Custom Weir/Orifice ( Controls 0.00 cfs) Page 22 11/04/19 Type II 24-hr 10 - year Rainfall=3.83"Drainage Calculations Printed 11/4/2019Prepared by Windows User Page 3HydroCAD® 10.00-24 s/n 08312 © 2018 HydroCAD Software Solutions LLC Summary for Pond 3P: Proposed Driveway [57] Hint: Peaked at 866.97' (Flood elevation advised) Inflow Area = 239.010 ac, 0.00% Impervious, Inflow Depth = 1.28" for 10 - year event Inflow = 129.36 cfs @ 12.85 hrs, Volume= 25.477 af Outflow = 129.36 cfs @ 12.85 hrs, Volume= 25.477 af, Atten= 0%, Lag= 0.0 min Primary = 129.36 cfs @ 12.85 hrs, Volume= 25.477 af Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Peak Elev= 866.97' @ 12.85 hrs Device Routing Invert Outlet Devices #1 Primary 863.12'57.0" W x 38.0" H, R=28.9"/88.3" Pipe Arch CMP_Arch_1/2 57x38 L= 30.0' CMP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 863.12' / 863.08' S= 0.0013 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 11.89 sf #2 Primary 866.75'Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 0.50 Width (feet) 160.00 390.00 Primary OutFlow Max=129.06 cfs @ 12.85 hrs HW=866.97' (Free Discharge) 1=CMP_Arch_1/2 57x38 (Barrel Controls 62.00 cfs @ 5.41 fps) 2=Custom Weir/Orifice (Weir Controls 67.06 cfs @ 1.46 fps) Page 23 11/04/19 Type II 24-hr 100 - year Rainfall=6.46"Drainage Calculations Printed 11/4/2019Prepared by Windows User Page 4HydroCAD® 10.00-24 s/n 08312 © 2018 HydroCAD Software Solutions LLC Summary for Pond 3P: Proposed Driveway [57] Hint: Peaked at 867.25' (Flood elevation advised) Inflow Area = 239.010 ac, 0.00% Impervious, Inflow Depth = 3.27" for 100 - year event Inflow = 355.53 cfs @ 12.83 hrs, Volume= 65.202 af Outflow = 355.53 cfs @ 12.83 hrs, Volume= 65.202 af, Atten= 0%, Lag= 0.0 min Primary = 355.53 cfs @ 12.83 hrs, Volume= 65.202 af Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.05 hrs Peak Elev= 867.25' @ 12.83 hrs Device Routing Invert Outlet Devices #1 Primary 863.12'57.0" W x 38.0" H, R=28.9"/88.3" Pipe Arch CMP_Arch_1/2 57x38 L= 30.0' CMP, projecting, no headwall, Ke= 0.900 Inlet / Outlet Invert= 863.12' / 863.08' S= 0.0013 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 11.89 sf #2 Primary 866.75'Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 0.50 Width (feet) 160.00 390.00 Primary OutFlow Max=354.73 cfs @ 12.83 hrs HW=867.25' (Free Discharge) 1=CMP_Arch_1/2 57x38 (Barrel Controls 65.72 cfs @ 5.55 fps) 2=Custom Weir/Orifice (Weir Controls 289.02 cfs @ 2.12 fps) Page 24 11/04/19 EXISTING BASIN 163,750 SF Tc ROUTETc ROUTE EXISTING DRAINAGE BASINS 4545 W. 141st Street CARMEL, IN 46074 Red Barn Engineering Company, LLC Civil Engineering Consulting Services 317.677.6797 Chris@RedBarnEngineeringCo.com SCALE: 1"=100' 11/04/19 Page 25 11/04/19 WATERSHED TOTAL TOTAL Roof (sf)Pond (sf)1/2 acre lots Pavement (sf)Lawn (sf)Light Woods Bare Earth Woods (sf) AREA (ac)AREA (sf)WEIGHTED WEIGHTED Runoff Coefficient 0.90 0.90 0.35 0.85 0.20 0.25 0.55 0.20 RUNOFF C RUNOFF CN Curve Number 98.00 98.00 73.92 98.00 67.15 70.70 68.71 62.63 Overall Creek Basin 239.01 10411230 0 426890 2597725 191025 3263885 2109190 703060 1119455 0.31 71.01 Existing Basin 3.76 163750 0 0 0 131000 24563 0 8188 0.21 67.45 Proposed Basin 3.76 163750 6050 10900 11330 102720 24563 0 8188 0.32 72.78 WATERSHED AREA (ac)Hydrologic % of Total Group Area Soil Map Basin 8.20 C 2.92 280.9 0.90 B 0.32 28.90 B 10.29 8.60 C 3.06 9.80 3.49 50.10 C 17.84 111.90 C 39.84 62.50 B 22.25 92.30 32.86 178.80 63.65 WATERSHED Weighted Group B Group C CN Value Weighted Percentage 32.86 63.65 61 74 67.1 66 77 70.7 58 78 68.7 55 70 62.6 70 80 73.9 98 98 98.0 98 98 98.0 DEVELOPED SITE DRAINAGE BASIN C FACTOR CALCULATIONS Brookston DRAINAGE BASIN SOIL TYPE BREAKDOWN Soil Type Gessie Group B Group C SOIL CURVE NUMBER CALCULATIONS Cover Type and HERPICC CN Hydraulic Condition Miami Shoals Water Urban - Brookston Urban - Miami Urban - Crosby Pavement Lawn Light Woods Field Woods 1/2 acre lots Pond Page 26 11/04/19 Project: 4545 W. 141st Street Residence Location: Carmel, IN Date: 11/4/2019 Check One: BASIN NAME :Existing / Proposed On-Site Ba Sheet Flow Segment ID A-B Surface description (table 3-1)..........................Grass Smooth Manning's roughness coefficient, n (table 3-1)….0.24 0.011 Flow length, L (total L<=300f..........................ft.100 Two-yr 24hr rainfall, p2...................................in.2.66 Land slope, s..............................................ft/ft 0.01 Tt = 0.0043 (nL)0.8 Computed T......................hr.0.345 0.000 S0.4 Shallow Concentrated Flow Segment ID B-C C-D Surface description (paved or unpaved)...............unpaved paved Flow length, L................................................ft.485 0 Watercourse slope, s...................................ft/ft 0.01 0 Average velocity, V (figure 3-1)......................ft/s 1.61 0.00 Tt = L/(3600 V) Computed Tt…………..……...hr.0.083 0.000 Channel Flow Segment ID Cross sectional flow area, a............................ft2 Wetted perimeter, PW....................................ft. Hydraulic radius, r=a/PW Compute……..…....ft. Channel slope,s.........................................ft/ft Manning's roughness coefficeint,n………...……. V =(1.49 r2/3 s1/2)/n Compute………………...ft/s Flow length, L ..............................................ft. Tt = L/(3600 V) Computed Tt………..………...hr. Pipe Flow Segment ID C-D Velocity......................................................ft/s 3 Length..........................................................ft.60 Tt=L/(3600v) Computed Tt…………..……....hr.0.006 Watershed or subarea Tc or Tt..................hr.0.434 Watershed or subarea Tc or Tt...............min.26.0 Time of Concentration (Tc) Worksheet Pre-Development Post-Development Page 27 11/04/19 872 DRY DETENTION BASIN 100-YEAR ELEV. = 866.35 175' O F 6 " P E R F O R A T E D SUB- S U R F A C E D R A I N 867 866 867 866 867867866865866867 867866 865866867866 Tc ROUTETc ROUTE PROPOSED BASIN 163,750 SF PROPOSED DRAINAGE BASINS 4545 W. 141st Street CARMEL, IN 46074 Red Barn Engineering Company, LLC Civil Engineering Consulting Services 317.677.6797 Chris@RedBarnEngineeringCo.com SCALE: 1"=100' 11/04/19 Page 28 11/04/19 WATERSHED TOTAL TOTAL Roof (sf)Pond (sf)1/2 acre lots Pavement (sf)Lawn (sf)Light Woods Bare Earth Woods (sf) AREA (ac)AREA (sf)WEIGHTED WEIGHTED Runoff Coefficient 0.90 0.90 0.35 0.85 0.20 0.25 0.55 0.20 RUNOFF C RUNOFF CN Curve Number 98.00 98.00 73.92 98.00 67.15 70.70 68.71 62.63 Overall Creek Basin 239.01 10411230 0 426890 2597725 191025 3263885 2109190 703060 1119455 0.31 71.01 Existing Basin 3.76 163750 0 0 0 131000 24563 0 8188 0.21 67.45 Proposed Basin 3.76 163750 6050 10900 11330 102720 24563 0 8188 0.32 72.78 WATERSHED AREA (ac)Hydrologic % of Total Group Area Soil Map Basin 8.20 C 2.92 280.9 0.90 B 0.32 28.90 B 10.29 8.60 C 3.06 9.80 3.49 50.10 C 17.84 111.90 C 39.84 62.50 B 22.25 92.30 32.86 178.80 63.65 WATERSHED Weighted Group B Group C CN Value Weighted Percentage 32.86 63.65 61 74 67.1 66 77 70.7 58 78 68.7 55 70 62.6 70 80 73.9 98 98 98.0 98 98 98.0 DEVELOPED SITE DRAINAGE BASIN C FACTOR CALCULATIONS Brookston DRAINAGE BASIN SOIL TYPE BREAKDOWN Soil Type Gessie Group B Group C SOIL CURVE NUMBER CALCULATIONS Cover Type and HERPICC CN Hydraulic Condition Miami Shoals Water Urban - Brookston Urban - Miami Urban - Crosby Pavement Lawn Light Woods Field Woods 1/2 acre lots Pond Page 29 11/04/19 0.32 3.76 3.76 0.38 1.13 Total Tc(A) Area(C) Runoff Coef.(I) Intensity(Q) Runoff CFSOutlet CFSStorage RateVolume acre-ftTotal Tc(A) Area(C) Runoff Coef.(I) Intensity(Q) Runoff CFSOutlet CFSStorage RateVolume acre-ft0.08 3.76 0.32 6.12 7.3636 0.38 6.988 0.047 0.08 3.76 0.32 9.12 11.0 1.13 9.8452 0.066 0.17 3.76 0.32 5.22 6.2807 0.38 5.905 0.084 0.17 3.76 0.32 7.78 9.4 1.13 8.2329 0.117 0.25 3.76 0.32 4.55 5.4746 0.38 5.099 0.106 0.25 3.76 0.32 6.77 8.1 1.13 7.0177 0.146 0.33 3.76 0.32 4.02 4.8369 0.38 4.461 0.123 0.33 3.76 0.32 5.99 7.2 1.13 6.0792 0.167 0.50 3.76 0.32 3.30 3.9706 0.38 3.595 0.150 0.50 3.76 0.32 4.84 5.8 1.13 4.6955 0.196 0.66 3.76 0.32 2.71 3.2607 0.38 2.885 0.159 0.66 3.76 0.32 4.05 4.9 1.13 3.745 0.206 1.00 3.76 0.32 2.03 2.4425 0.38 2.066 0.172 1.00 3.76 0.32 3.03 3.6 1.13 2.5177 0.210 2.00 3.76 0.32 1.11 1.3356 0.38 0.96 0.160 2.00 3.76 0.32 1.87 2.2 1.13 1.122 0.187 3.00 3.76 0.32 0.84 1.0107 0.38 0.635 0.159 3.00 3.76 0.32 1.42 1.7 1.13 0.5805 0.145 6.00 3.76 0.32 0.50 0.6016 0.38 0.226 0.113 6.00 3.76 0.32 0.85 1.0 1.13 -0.105 -0.053 12.00 3.76 0.32 0.29 0.3489 0.38 -0.03 -0.027 12.00 3.76 0.32 0.48 0.6 1.13 -0.55 -0.550 24.00 3.76 0.32 0.16 0.1925 0.38 -0.18 -0.367 24.00 3.76 0.32 0.27 0.3 1.13 -0.803 -1.606 0.172 0.210 7501 9139 D = 4" Orifice D = 1" Orifice Q=CA(2gh)^1/2 Q=CA(2gh)^1/2 C =0.61 C =0.61 A =0.087 A =0.0055 g =32.2 g =32.2 h =0.40 h =0.90 Q=0.27 cfs Q=0.03 cfs Estimated 100-year flow (x1.25) =9.01 cfs Q=(1.49/n)*(R^2/3)*A*(S^1/2) Manning's "n" = 0.02 Bottom width =30 Height =0.25 Side slope (1/x) x=3 Slope (ft/ft)=0.0022 Wetted Perimeter = 31.581 Area =7.6875 Hydraulic Radius =0.2434 Q=10.473 RATIONAL DETENTION CALCULATIONS Orifice Discharge Computations Equation Total (ft^3)9659 866.00 10900 5450 0.1251 866.25 12390 Pond Spillway Calculations 865.00 0 Total (acre-ft)=0.2217 2911 0.0668 866.35 13560 1298 0.0298 10-Year Event (ft^3) = 100-Year Event (ft^3) = Detention Volume Provided Surface Storage Contour Area (S.F.)Average (S.F.)Vol. (acre-ft) 10 Year Post-Developed Storm 100 Year Post-Developed Storm Detention Volume Required 10-Year Event (acre-ft) = 100-Year Event (acre-ft) = Area (acres) = Area (acres) = Allow. Release Rate x0.1 (cfs) = Allow. Release Rate x0.3 (cfs) = Residential Construction - 4545 W. 141st Street Runoff Coef. = 10-Year 100-Year Page 30 11/04/19 A=Drainage area 3.76 Ac I=Post-development impervious percentage 17.3% P=Precipitation 1.00 in Rv=Volumetric Runoff Coefficient Rv = 0.05 + .009 (I) =0.205 in/in WQv=Water Quality Volume WQv = (P) (Rv) (A) / 12 =0.06 ac-ft 0.071 Provided at or 2804 ft^3 Elev. =865.90 ENp=Elevation of Normal Pool 865.00 ESt=Elevation of Water Quality 865.90 h=Height Height (h) = (Enp - Es) / 2 =0.45 ' Q=Water Quality Release Rate (over 24 hours) Q = (WQv * 43560) / (24 * 3600) =0.032 cfs a=Q Orifice Equation C * 2 * (g *h) ^0.5 C=Orifice constant 0.6 g=Gravity constant 32.2 a=Area of orifice a=0.007 sq.ft. d=Diameter of Orifice d=0.095 ' or 1.142 " Designed orifice = 1 inches m Area Area Volume Volume (msl)(sf)(ac)(cu-ft)(ac-ft) 865.00 0 0.0000 0 0.0000 865.00 0 0.0000 0 0.0000 865.85 9265 0.2127 2622 0.0602 865.90 9810 0.2252 3099 0.0711 865.95 10355 0.2377 3602 0.0827 866.00 10900 0.2502 4133 0.0949 3099 0.0711 WATER QUALITY DESIGN CALCULATIONS Proposed Retention Pond WQv TOTAL WQ Storage Volume Page 31 11/04/19