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HomeMy WebLinkAboutDrainage Calculations 06-16-23WHITE RIVER GREENWAY TRAIL & TRAILHEAD 14001 River Road Carmel, Indiana 46033 SJCA PROJ: 21EN019 DRAINAGE CALCULATIONS __________________________ __ ____ BENJAMIN E. DEICHMANN, P.E. NO. 10809477 June 16, 2023 DATE 9102 North Meridian Street, Suite 200 Indianapolis, IN 46260 Ph: (317) 566-0629 Fx: (317) 566-0633 TABLE OF CONTENTS SECTION PAGE Section 1-Project Summary Project Overview………………………………………………………….......................3 –9 Section 2-Hydrology Existing Conditions………………………………………………….………………………...11 –16 Proposed Conditions………………………………………………….……………………...17 –21 Section 3-Detention Calculations Detention Calculations…………………………………………….………………………...22 –34 By: BED 6/16/2023 Page: 2 of 34 Section 1- Project Summary By: BED 6/16/2023 Page: 3 of 34 Project Overview – White River Greenway Trail & Trailhead Site Description This site is located on the east side of River Road at the intersection of River Road and Haverton Way, in Carmel, Indiana. The project site is approximately 4.72 acres and consists of undeveloped land; the proposed improvements will disturb +/-1.56 acres. The site generally sheet drains to the east, towards the White River, and is covered with grass and trees/brush. The proposed site improvements will consist of a multi-use pathway, trailhead parking area w/ restroom facility, river overlook structure, and associated infrastructure improvements. Run-off from the proposed site improvements will be collected by the proposed infiltration basin facility. The ultimate receiving water for the site is the White River. The existing zoning and land uses adjacent to the site are as follows: North:S-1 – Vacant West:S-1 - Residential South:P-1 - Park East:OM – Museum Soil Types Soil maps from the United States Department of Agriculture, Soil Conservation Service, identify Fox clay loam- Urban land complex, 8 to 18 percent slopes (YfpD3 – 21% of site) and Ockley silt loam-Urban land complex, 0 to 2 percent slopes (YoxA – 73% of site). The remaining 0.3 acres of the site consists of the White River. The Fox and Ockley soils are classified as a type “B” soil. Group B soils are generally characterized as having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Fox clay loam-Urban land complex soil is moderately sloped, deep, moderately-drained soil. The main soil features that adversely affect engineering uses of this soil are moderate shrink-swell potential, moderate potential frost action and moderate permeability. Development can occur as long as proper drainage is provided, using properly designed foundations, footings and additional under-drain systems along with proper compaction. Undercutting of the soil may be necessary in areas of poor compaction. Ockley silt loam-Urban land complex soil is nearly level, deep, well-drained soil. The main soil features that adversely affect engineering uses of this soil are moderate shrink-swell potential, moderate potential frost action and moderate permeability. Development can occur as long as proper drainage is provided, using properly designed foundations, footings and additional under-drain systems along with proper compaction. Design Method and Criteria 1.Design Storm: The 2-year, 10-year and 100-year storm events have been analyzed for the existing and proposed conditions utilizing the Rational Method. 2. Overall Watershed: White River. References 1.TR55 Stormwater Design Manual. 2.The City of Carmel Stormwater Technical Standards Manual. 3.Hamilton County Soil Survey. By: BED 6/16/2023 Page: 4 of 34 HOLLOW OAKTRL HAVERTON W AY LOSTOAKSDRRIVERRDWHITERIVERTALL TIMBERRUN White River Greenway Trailhead Parcels City Boundary 2022 Photography Red: Red Green: Green Blue: Blue June 27, 2023 0 0.03 0.060.01 mi 0 0.04 0.090.02 km 1:1,800 ArcGIS WebApp BuilderBy: BED 6/16/2023 Page: 5 of 34 Soil Map—Hamilton County, Indiana (White River Greenway Trailhead) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/23/2023 Page 1 of 3442659044266304426670442671044267504426790442683044268704426910442659044266304426670442671044267504426790442683044268704426910581240581280581320581360581400581440581480 581240 581280 581320 581360 581400 581440 581480 39° 59' 18'' N 86° 2' 54'' W39° 59' 18'' N86° 2' 43'' W39° 59' 7'' N 86° 2' 54'' W39° 59' 7'' N 86° 2' 43'' 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: 1:1,620 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. By: BED 6/16/2023 Page: 6 of 34 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 23, Sep 3, 2022 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jun 15, 2022—Jun 21, 2022 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 (White River Greenway Trailhead) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/23/2023 Page 2 of 3By: BED 6/16/2023 Page: 7 of 34 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI W Water 0.3 5.9% YfpD3 Fox clay loam-Urban land complex, 8 to 18 percent slopes, severely eroded 1.1 21.3% YoxA Ockley silt loam-Urban land complex, 0 to 2 percent slopes 3.8 72.8% Totals for Area of Interest 5.2 100.0% Soil Map—Hamilton County, Indiana White River Greenway Trailhead Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/23/2023 Page 3 of 3 By: BED 6/16/2023 Page: 8 of 34 National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250 Feet Ü SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOOD HAZARD AREAS Without Base Flood Elevation (BFE) Zone A, V, A99 With BFE or DepthZone AE, AO, AH, VE, AR Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mileZone X Future Conditions 1% Annual Chance Flood HazardZone X Area with Reduced Flood Risk due to Levee. See Notes.Zone X Area with Flood Risk due to LeveeZone D NO SCREEN Area of Minimal Flood Hazard Zone X Area of Undetermined Flood HazardZone D Channel, Culvert, or Storm Sewer Levee, Dike, or Floodwall Cross Sections with 1% Annual Chance 17.5 Water Surface Elevation Coastal Transect Coastal Transect Baseline Profile Baseline Hydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of Study Jurisdiction 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 the authoritative NFHL web services provided by FEMA. This map was exported on 8/24/2021 at 12:17 PM and does not reflect changes or amendments subsequent to this date and time. The NFHL and effective information may change or become superseded by new data over time. This map image is void if the one or more of the following map elements 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 for unmapped and unmodernized areas cannot be used for regulatory purposes. Legend OTHER AREAS OF FLOOD HAZARD OTHER AREAS GENERAL STRUCTURES OTHER FEATURES MAP PANELS 8 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. 1:6,000 86°3'8"W 39°59'26"N 86°2'30"W 39°58'58"N Basemap: USGS National Map: Orthoimagery: Data refreshed October, 2020 By: BED 6/16/2023 Page: 9 of 34 Section 2- Hydrology By: BED 6/16/2023 Page: 10 of 34 EXISTING CONDITIONS By: BED 6/16/2023 Page: 11 of 34 Existing Conditions This site is located on the east side of River Road just east of the intersection of River Road and Haverton Way, in Carmel, Indiana. The project site is approximately 5.16 acres and is undeveloped. Existing on-site conditions were established for the project site and was found to have 1 drainage basin (EX1). Run-off associated with basin EX1 sheet flows in an easterly direction. Basin EX1 is undeveloped and covered with grass and wooded/brush areas. Basin EX1 was found to be 4.82 acres, a weighted runoff coefficient (“c”) of 0.20 and a time-of-concentration of 15 minutes. Run-off from Basin EX1 sheet flows to the east and it ultimately drains to the White River. Existing off-site conditions for the right-of-way along River Road was established and found to consist of 1.48 acres, a weighted runoff coefficient “c” of 0.45 and time-of-concentration of 5 minutes. Existing Hydrology Calculations Hydrology calculations for the existing on-site basin (EX1) and off-site basin (RIVER ROAD) are attached. The Rational Method was used to compute the 2-year, 10-year and 100-year run-off rates from the site. BASINS EX1 RIVER ROAD 2-year 2.82 cfs 3.14 cfs 10-year 4.33 cfs 4.61 cfs 100-year 6.21 cfs 6.40 cfs By: BED 6/16/2023 Page: 12 of 34 SJCA7:10:11 PM6/27/2023Model:Site and Utility PlanH:\Projects\2021\Engineering\21EN019_WHITE_RIVER_GREENWAY_NORTH_EXTENSION_SJCA\CAD\Sheets\EX1.dgnUser:PersonalChecked:REVISIONProject #:Scale:Date:DATEDrawn:SYMSHEETSSHEET11OFBefore You Dig.Call Two Full Working Days Per Indiana State Law IC8-1-26,SJCA Inc.P RELIM IN ARY07/30/2021Field Survey:02/28/202302/28/2023Phone: (317) 566-06299102 North Meridian Street, Suite 200, Indianapolis, IN 46260NORTH TRAIL EXTENSIONWHITE RIVER GREENWAYHAMILTON COUNTY, INDIANACARMEL CLAY PARKS & RECREATION21EN019EX. RIGHT-OF-WAY EX. RIGHT-OF-WAY EX. RIGHT-OF-WAYEX. RIGHT-OF-WAYPROP. LINEPROP. LINE P ROP . L IN E PROP. LINE RB-0 RB-0 TR TR BM IPn CONCRETEGRASS CONCRETE ASPHALT ASPHALT 75075175 1752752735736736738739740 740 740 741 7 41741 741 741742742 742742 742 743 743 743 743743743743 744 744 744744 744 744745 745 745745745 745 746 746746 746746 746 746 747 747 747747747 747 747 748748 748 748748748 748749749 749749 749 749 749 750 750 750 750 750 750750751 751751 751 751 751 751751752 752 752 752 752 752752752752753753753 753 753 753 753 753 753 7547 54 754 754754 754 754 755755 755 755755GPS CONTROL DIRT TRAIL DIRT PATH CONNECT CEC INCCEC INCCEC INCCEC INC ELEV. = 756.5960' BONNET BOLT OF FIRE HYDRANT TBM #6: CUT "X" ON NE INV. 12" CMP = 753.04' TAX ID: 29-10-23-000-003.000-018 INSTR. 2016025352 CARMEL/CLAY BOARD OF PARKS AND RECREATION EX1EXISTING SITE CONDITIONSLEGEND GRAVEL A/CFFE EM MON SM MAG RB-0 GM WM T CB ASPHALT MH R/W GRASS MULCH CB T-P BM BENCHMARK R/W MARKER CONTROL - REBAR CONTROL - MAG NAIL CONTROL - MONUMENT CONTROL - STONE MOMUNENT CATCH BASIN - ROUND CATCH BASIN - SQUARE GRASS AREA MULCH AREA PARKING BUMPER GRAVEL AREA ASPHALT AREA FINISHED FLOOR ELEVATION T-POST POST SINGLE POST SIGN CONIFEROUS TREE DECIDUOUS TREE BUSH METER - WATER LIGHT ON POWER POLE A/C UNIT POWER POLE MANHOLE TELEPHONE MANHOLE FIRE HYDRANT GUY ROPE ANCHOR METER - ELECTRIC METER - GAS EXISTING SYMBOLS PPST WV SITE BOUNDARY EXISTING DRAINAGE PIPE EXISTING CHAIN LINK FENCE EXISTING GUARDRAIL EXISTING TREELINE EXISTING OVERHEAD UTILITY EXISTING UNDERGROUND CABLE UTILITY EXISTING UNDERGROUND ELECTRIC UTILITY EXISTING UNDERGROUND GAS UTILITY EXISTING UNDERGROUND SANITARY UTILITY EXISTING UNDERGROUND WATER UTILITY SITE BOUNDARY NOTE 050'50'100'150'1" = 100'INFORMATION REGARDING PROPERTY BOUNDARY, EASEMENTS, AND RIGHT-OF-WAY. SURVEY PERFORMED BY SJCA, INC. ON JULY 30, 2021. SEE RECORD SURVEYS FOR EXACT THESE PLANS WERE PREPARED WITH SURVEY INFORMATION BASED ON A TOPOGRAPHIC Tc=15 MINUTES RUNOFF COEFF. "c"=0.20 AREA=4.82 ACRES BASIN EX1 Tc=5 MINUTES RUNOFF COEFF. "c"=0.45 AREA=1.48 ACRES 2BASIN EX By: BED 6/16/2023 Page: 13 of 34 Time of Concentration Worksheet PROJECT: White River Greenway and Trailhead Based on TR-55 JOB #: 21EN019 Typical values for Manning's n Typical values for Manning's n Overland Flow 2 year, 24 hour rainfall =2.66 inches Channel Flow short grass 0.150 grass 0.030 dense grass 0.240 concrete 0.015 pavement 0.011 rip-rap 0.035 Overland flow seg. 1 Overland flow seg. 2 Shallow Concentrated Flow Channel Flow Basin Length S n T_t Length S n T_t Length S Paved/Un Vel.T_t Length a Pw r S n Vel.T_t T_c name (ft)%(min)(ft)%(min)(ft)%(P or U)(ft/s)(min)(ft)(s.f.)(ft)(ft)%(ft/s)(min)(min) EX1 100 1.00 0.150 14 120 1.00 U 1.61 1 15 EX2 50 1.00 0.011 1 5 Str. 10 100 1.00 0.150 14 14 Str. 12 100 1.00 0.150 14 260 1.00 U 1.61 3 17 Str. 13 100 1.00 0.150 14 260 1.00 U 1.61 3 17 PR1 100 1.00 0.150 14 120 1.00 U 1.61 1 15 102 50 1.00 0.011 1 20 1.00 U 1.61 0 5 104 100 1.00 0.011 2 20 1.00 U 1.61 0 5 By: BED 6/16/2023 Page: 14 of 34 EXISTING OVERALL CONDITIONS 21EN019 - White River Greenway Trailhead Runoff Curve Coefficient Number Roof Area =0.90 98 Impervious Area =0.85 98 Open Area =0.20 61 Slightly pervious soil w/ turf, Forested areas Gravel/Stone =0.85 85 Fox clay loam-Urban land complex, 8 to 18 percent slopes (YfpD3 – 21% of site) -Type "B" soil Ockley silt loam-Urban land complex, 0 to 2 percent slopes (YoxA – 73% of site) -Type "B" soil ON SITE (EX1) Roof Area Impervious Area Open Area Stone Total Total Composite Composite (ft^2)(ft^2)(ft^2)(ft^2)(ft^2)(Acres)"c""CN" 0 0 209982 0 209982 4.82 0.20 61 OFF SITE (EX2) - RIVER ROAD 1/2 ROW Roof Area Impervious Area Open Area Stone Total Total Composite Composite (ft^2)(ft^2)(ft^2)(ft^2)(ft^2)(Acres)"c""CN" 0 24459 39906 0 64365 1.48 0.45 75 ON SITE (STR 10) Roof Area Impervious Area Open Area Stone Total Total Composite Composite (ft^2)(ft^2)(ft^2)(ft^2)(ft^2)(Acres)"c""CN" 0 0 41955 0 41955 0.96 0.20 61 OFF SITE (STR 12) Roof Area Impervious Area Open Area Stone Total Total Composite Composite (ft^2)(ft^2)(ft^2)(ft^2)(ft^2)(Acres)"c""CN" 0 0 206455 0 206455 4.74 0.20 61 OFF SITE (STR 13) Roof Area Impervious Area Open Area Stone Total Total Composite Composite (ft^2)(ft^2)(ft^2)(ft^2)(ft^2)(Acres)"c""CN" 0 0 123610 0 123610 2.84 0.20 61 By: BED 6/16/2023 Page: 15 of 34 EXISTING RUNOFF CALCULATION - RATIONAL METHOD PROJECT NAME White River Greenway and Trailhead PROJECT No. 21EN019 STORM FREQUENCY DESIGN YEAR 2 LOCATION INLET ACRES COEF.SUM TIME CONC. (min)INT."Q" = from to AREA sub total "C"CA CA inlet drain total "I"CIA EX1 4.82 0.20 0.96 15 15 2.92 2.82 EX2 1.48 0.45 0.66 5 5 4.75 3.14 Str. 10 0.96 0.20 0.19 14 14 3.05 0.59 Str. 12 4.74 0.20 0.95 17 17 2.78 2.64 Str. 13 2.84 0.20 0.57 17 17 2.78 1.58 STORM FREQUENCY DESIGN YEAR 10 LOCATION INLET ACRES COEF.SUM TIME CONC. (min)INT."Q" = from to AREA sub total "C"CA CA inlet drain total "I"CIA EX1 4.82 0.20 0.96 15 15 4.49 4.33 EX2 1.48 0.45 0.66 5 5 6.98 4.61 Str. 10 0.96 0.20 0.19 14 14 4.68 0.90 Str. 12 4.74 0.20 0.95 17 17 4.29 4.06 Str. 13 2.84 0.20 0.57 17 17 4.29 2.43 STORM FREQUENCY DESIGN YEAR 25 LOCATION INLET ACRES COEF.SUM TIME CONC. (min)INT."Q" = from to AREA sub total "C"CA CA inlet drain total "I"CIA EX1 4.82 0.20 0.96 15 15 5.27 5.08 EX2 1.48 0.45 0.66 5 5 8.08 5.34 Str. 10 0.96 0.20 0.19 14 14 5.48 1.06 Str. 12 4.74 0.20 0.95 17 17 5.03 4.77 Str. 13 2.84 0.20 0.57 17 17 5.03 2.86 STORM FREQUENCY DESIGN YEAR 100 LOCATION INLET ACRES COEF.SUM TIME CONC. (min)INT."Q" = from to AREA sub total "C"CA CA inlet drain total "I"CIA EX1 4.82 0.20 0.96 15 15 6.44 6.21 EX2 1.48 0.45 0.66 5 5 9.69 6.40 Str. 10 0.96 0.20 0.19 14 14 6.70 1.29 Str. 12 4.74 0.20 0.95 17 17 6.17 5.85 Str. 13 2.84 0.20 0.57 17 17 6.17 3.50 06/16/23 By: BED 6/16/2023 Page: 16 of 34 PROPOSED CONDITIONS By: BED 6/16/2023 Page: 17 of 34 Proposed Conditions The proposed site improvements will consist of a multi-use pathway, trailhead parking area w/ restroom facility, river overlook structure, and associated infrastructure improvements. Run-off from the proposed site improvements will be collected by the proposed infiltration basin facility. Proposed on-site conditions were established for the project site and it was found to have 1 drainage basin (PR1). Basin PR1 consists of the proposed trailhead parking area, multi-use pathway and river overlook structure. Basin PR1 was found to be 4.82 acres, a weighted runoff coefficient (“c”) of 0.27 and a time-of- concentration of 15 minutes. Run-off from Basin PR1 will be collected by proposed stormwater infiltration basin located along the west side of the project site. Proposed Hydrology Calculations Hydrology calculations for the proposed on-site basin (PR1) are attached. The Rational Method was used to compute the 2-year, 10-year and 100-year run-off rates from the site. BASIN PR1 2-year 3.87 cfs 10-year 5.94 cfs 100-year 8.52 cfs By: BED 6/16/2023 Page: 18 of 34 SJCAFFE = 755.15 755.41 755.91 754.69 755.19 754.14 754.14 755.41 755.91 755.16 755.16 755.26 755.76 755.26 755.76 755.11 755.11 755.66 755.66 755.00 755.50 7:16:16 PM6/27/2023Model:Site and Utility PlanH:\Projects\2021\Engineering\21EN019_WHITE_RIVER_GREENWAY_NORTH_EXTENSION_SJCA\CAD\Sheets\PR1.dgnUser:PersonalChecked:REVISIONProject #:Scale:Date:DATEDrawn:SYMSHEETSSHEET11OFBefore You Dig.Call Two Full Working Days Per Indiana State Law IC8-1-26,SJCA Inc.P RELIM IN ARY07/30/2021Field Survey:02/28/202302/28/2023Phone: (317) 566-06299102 North Meridian Street, Suite 200, Indianapolis, IN 46260NORTH TRAIL EXTENSIONWHITE RIVER GREENWAYHAMILTON COUNTY, INDIANACARMEL CLAY PARKS & RECREATION21EN019754.55753.93754.25 754.75 753.71 754.21 754.85 755.35 753.71 754.21 754.25 754.75 754.85 755.35 754754 754753752751752753755 100 101 102 103 104 754.70 754.70 EX. RIGHT-OF-WAY EX. RIGHT-OF-WAY EX. RIGHT-OF-WAYEX. RIGHT-OF-WAYPROP. LINEPROP. LINE PR OP . L INE PROP. LINE754.70 754.70 754.92 755.42 7 5 5. 2 5 FLAT-TOP 3-SIDED STRUCTURE 28 LF OF 14' SPAN x 12' RISE PRECAST 753.29 754.60 754.60 753.50 754.00 753.50 754.00 754.67 754.67 754.58 754.58 207 LF OF 12" RCP @ 0.31% INV = 750.14 6" PERF. SSD INV = 747.75 6" PERF. SSD BOTTOM ELEV = 749.50 PROPOSED INFILTRATION BASIN BOTTOM ELEV = 751.90 PROPOSED INFILTRATION BASINWV8 LF OF 15" RCP @ 0.21% INV. SW = 750.14 (12") INV. NE = 750.14 (6") TC = 752.00 STR. 104 INV = 749.50 STR. 103 INV. SE= 747.75 (15") INV. NW = 747.75 (6") TC = 752.00 STR. 102 INV. SE = 747.63 (15") INV. NW = 747.73 (15") TC = 753.00 STR. 101 INV = 747.27 STR. 100 RB-0 RB-0 TR TR BM IPn CONCRETEGRASS CONCRETE ASPHALT ASPHALT 75075175 1752752735736736738739740 740 740 741 7 41741 741 741742742 742742 742 743 743 743 743743743743 744 744 744744 744 744745 745 745745745 745 746 746746 746746 746 746 747 747 747747747 747 747 748748 748 748748748 748749749 749749 749 749 749 750 750 750 750 750 750750751 751751 751 751 751 751751752 752 752 752 752 752752752752753753753 753 753 753 753 753 753 7547 54 754 754754 754 754 755755 755 755755GPS CONTROL DIRT TRAIL DIRT PATH CONNECT CEC INCCEC INCCEC INCCEC INC ELEV. = 756.5960' BONNET BOLT OF FIRE HYDRANT TBM #6: CUT "X" ON NE INV. 12" CMP = 753.04' 8" HDPE ROOF DRAIN 172 LF OF 15" R C P @ 0.21 %R OADR IVE R WA Y H A VERT O N WHITE RIVER CARMEL/CLAY BOARD OF PARKS AND RECREATION INSTR. 2016025352 TAX ID: 29-10-23-000-003.000-018 PR1PROPOSED SITE CONDITIONSLEGEND GRAVEL A/CFFE EM MON SM MAG RB-0 GM WM T CB ASPHALT MH R/W GRASS MULCH CB T-P BM BENCHMARK R/W MARKER CONTROL - REBAR CONTROL - MAG NAIL CONTROL - MONUMENT CONTROL - STONE MOMUNENT CATCH BASIN - ROUND CATCH BASIN - SQUARE GRASS AREA MULCH AREA PARKING BUMPER GRAVEL AREA ASPHALT AREA FINISHED FLOOR ELEVATION T-POST POST SINGLE POST SIGN CONIFEROUS TREE DECIDUOUS TREE BUSH METER - WATER LIGHT ON POWER POLE A/C UNIT POWER POLE MANHOLE TELEPHONE MANHOLE FIRE HYDRANT GUY ROPE ANCHOR METER - ELECTRIC METER - GAS EXISTING SYMBOLS PPST WV SITE BOUNDARY EXISTING DRAINAGE PIPE EXISTING CHAIN LINK FENCE EXISTING GUARDRAIL EXISTING TREELINE EXISTING OVERHEAD UTILITY EXISTING UNDERGROUND CABLE UTILITY EXISTING UNDERGROUND ELECTRIC UTILITY EXISTING UNDERGROUND GAS UTILITY EXISTING UNDERGROUND SANITARY UTILITY EXISTING UNDERGROUND WATER UTILITY SITE BOUNDARY NOTE 050'50'100'150'1" = 100'INFORMATION REGARDING PROPERTY BOUNDARY, EASEMENTS, AND RIGHT-OF-WAY. SURVEY PERFORMED BY SJCA, INC. ON JULY 30, 2021. SEE RECORD SURVEYS FOR EXACT THESE PLANS WERE PREPARED WITH SURVEY INFORMATION BASED ON A TOPOGRAPHIC Tc=15 MINUTES RUNOFF COEFF. "c"=0.27 AREA=4.82 ACRES BASIN PR1 By: BED 6/16/2023 Page: 19 of 34 PROPOSED OVERALL CONDITIONS 21EN019 - White River Greenway Trailhead Runoff Curve Coefficient Number Roof Area =0.90 98 Impervious Area =0.85 98 Open Area =0.20 61 Slightly pervious soil w/ turf, Forested areas Gravel/Stone =0.85 85 Fox clay loam-Urban land complex, 8 to 18 percent slopes (YfpD3 – 21% of site) -Type "B" soil Ockley silt loam-Urban land complex, 0 to 2 percent slopes (YoxA – 73% of site) -Type "B" soil ON SITE (PR1) Roof Area Impervious Area Open Area Stone Total Total Composite Composite (ft^2)(ft^2)(ft^2)(ft^2)(ft^2)(Acres)"c""CN" 407 23599 185975 0 209982 4.82 0.27 65 DISTURBED AREA (PR2) Roof Area Impervious Area Open Area Stone Total Total Composite Composite (ft^2)(ft^2)(ft^2)(ft^2)(ft^2)(Acres)"c""CN" 407 23599 30599 0 54605 1.25 0.49 77 ON SITE (102) Roof Area Impervious Area Open Area Stone Total Total Composite Composite (ft^2)(ft^2)(ft^2)(ft^2)(ft^2)(Acres)"c""CN" 407 3132 8353 0 11893 0.27 0.40 72 ON SITE (104) Roof Area Impervious Area Open Area Stone Total Total Composite Composite (ft^2)(ft^2)(ft^2)(ft^2)(ft^2)(Acres)"c""CN" 0 8948 8056 0 17005 0.39 0.54 80 By: BED 6/16/2023 Page: 20 of 34 PROPOSED RUNOFF CALCULATION - RATIONAL METHOD PROJECT NAME White River Greenway and Trailhead PROJECT No.21EN019 STORM FREQUENCY DESIGN YEAR 2 LOCATION INLET ACRES COEF.SUM TIME CONC. (min)INT."Q" = from to AREA sub total "C"CA CA inlet drain total "I"CIA PR1 4.82 0.27 1.32 15 15 2.92 3.87 Str. 102 0.27 0.40 0.11 5 5 4.75 0.51 Str. 104 0.39 0.54 0.21 5 5 4.75 1.01 STORM FREQUENCY DESIGN YEAR 10 LOCATION INLET ACRES COEF.SUM TIME CONC. (min)INT."Q" = from to AREA sub total "C"CA CA inlet drain total "I"CIA PR1 4.82 0.27 1.32 15 15 4.49 5.94 Str. 102 0.27 0.40 0.11 5 5 6.98 0.75 Str. 104 0.39 0.54 0.21 5 5 6.98 1.48 STORM FREQUENCY DESIGN YEAR 25 LOCATION INLET ACRES COEF.SUM TIME CONC. (min)INT."Q" = from to AREA sub total "C"CA CA inlet drain total "I"CIA PR1 4.82 0.27 1.32 15 15 5.27 6.97 Str. 102 0.27 0.40 0.11 5 5 8.08 0.87 Str. 104 0.39 0.54 0.21 5 5 8.08 1.71 STORM FREQUENCY DESIGN YEAR 100 LOCATION INLET ACRES COEF.SUM TIME CONC. (min)INT."Q" = from to AREA sub total "C"CA CA inlet drain total "I"CIA PR1 4.82 0.27 1.32 15 15 6.44 8.52 Str. 102 0.27 0.40 0.11 5 5 9.69 1.05 Str. 104 0.39 0.54 0.21 5 5 9.69 2.05 By: BED 6/16/2023 Page: 21 of 34 Section 3- Detention Calculations By: BED 6/16/2023 Page: 22 of 34 Detention Calculations To address the increase in stormwater run-off quantity, an infiltration basin is being proposed for the project site. The infiltration basin has not been designed to accommodate the run-off for the full build out of the right-of-way along the site’s frontage, a variance request to the Board of Works will be requested. As required by the Carmel Stormwater ordinance, the allowed 10-yr and 100-yr flow rates are 0.1 cfs/acre and 0.3 cfs/acre of disturbed area, respectively. The outlet point for the proposed stormwater detention facility will discharge to the east into the White River; therefore, the allowable release rate is based on the proposed disturbed area PR2 (1.25 acres). The allowable 10-yr and 100-yr discharge rates are 0.125 cfs and 0.375 cfs, respectively. The proposed infiltration basin will have a 12” thick stone bed with 12” of soil over top of it. The stone bed will have a 6” perforated sub-surface drain that will help drain the stone bed and will connect to an outlet control structure. The bottom of the stone bed will be at an elevation of 747.50 and the bottom of the infiltration basin will be at an elevation of 749.50. The outlet control structure is proposed at the infiltration basin to restrict the flows discharging from the site. A 1.5” circular orifice is proposed at an elevation 747.75 to control the 2-yr and 10-yr flows; however a 6” circular orifice will be installed to comply with the minimum orifice size. A 4” x 4” square orifice is proposed at an elevation of 750.85 to control the 100-yr flow. A 50’ wide emergency spillway is proposed at elevation 753.00 to control the 100-yr discharge and any storm events in excess of the 100-yr storm. The following are the computed 2-year, 10-year, and 100-year overall discharge rates and storage volumes from the proposed infiltration basin facility after being collected by the proposed basins. The following rates were calculated utilizing the Rational Method. PROPOSED INFILTRATION BASIN FACILITY RELEASE RATE STORAGE VOLUME POND ELEVATION Bottom of Stone N/A N/A 747.50 Bottom of Basin N/A N/A 749.50 2-year 0.10 cfs 957 cubic ft 750.57 10-year 0.10 cfs 1,305 cubic ft 750.82 100-year 0.37 cfs 1,775 cubic ft 751.10 Spillway N/A N/A 753.00 Top-of-Bank N/A N/A 754.00 The analysis indicated a 100-year elevation of the proposed infiltration basin of 751.10. We are proposing the emergency spillway at an elevation of 753.00. Conclusion The proposed trailhead has been designed to minimize the flooding potential of the site and an emergency spillway and flood routing has been incorporated into the project’s design. The proposed infiltration basin facility will reduce the overall stormwater run-off rate to receiving infrastructure and will aide in increasing groundwater recharge. By: BED 6/16/2023 Page: 23 of 34 PR2 Prop Disturbed Area 1P Pond Routing Diagram for 21EN019 Drainage Calcs Prepared by SJCA Inc., Printed 6/27/2023 HydroCAD® 10.00-26 s/n 07910 © 2020 HydroCAD Software Solutions LLC Subcat Reach Pond Link By: BED 6/16/2023 Page: 24 of 34 21EN019 Drainage Calcs Printed 6/27/2023Prepared by SJCA Inc. Page 2HydroCAD® 10.00-26 s/n 07910 © 2020 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) C Description (subcatchment-numbers) 1.250 0.49 (PR2) By: BED 6/16/2023 Page: 25 of 34 WR Greenway Trailhead 2-yr Duration=5 min, Inten=5.45 in/hr21EN019 Drainage Calcs Printed 6/27/2023Prepared by SJCA Inc. Page 3HydroCAD® 10.00-26 s/n 07910 © 2020 HydroCAD Software Solutions LLC Summary for Subcatchment PR2: Prop Disturbed Area Runoff =3.25 cfs @ 0.08 hrs, Volume=0.023 af, Depth= 0.22" Runoff by Rational method, Rise/Fall=1.0/1.0 xTc, Time Span= 0.00-24.00 hrs, dt= 0.01 hrs WR Greenway Trailhead 2-yr Duration=5 min, Inten=5.45 in/hr Area (ac)C Description 1.250 0.49 1.250 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet)(ft/ft) (ft/sec)(cfs) 5.0 Direct Entry, Subcatchment PR2: Prop Disturbed Area Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)3 2 1 0 WR Greenway Trailhead 2-yr Duration=5 min, Inten=5.45 in/hr Runoff Area=1.250 ac Runoff Volume=0.023 af Runoff Depth=0.22" Tc=5.0 min C=0.49 3.25 cfs By: BED 6/16/2023 Page: 26 of 34 WR Greenway Trailhead 2-yr Duration=5 min, Inten=5.45 in/hr21EN019 Drainage Calcs Printed 6/27/2023Prepared by SJCA Inc. Page 4HydroCAD® 10.00-26 s/n 07910 © 2020 HydroCAD Software Solutions LLC Summary for Pond 1P: Pond Inflow Area =1.250 ac, 0.00% Impervious, Inflow Depth = 0.22" for 2-yr event Inflow =3.25 cfs @ 0.08 hrs, Volume=0.023 af Outflow =0.10 cfs @ 0.17 hrs, Volume=0.023 af, Atten= 97%, Lag= 5.1 min Primary =0.10 cfs @ 0.17 hrs, Volume=0.023 af Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.01 hrs Peak Elev= 750.57' @ 0.17 hrs Surf.Area= 1,304 sf Storage= 957 cf Plug-Flow detention time= 86.7 min calculated for 0.023 af (100% of inflow) Center-of-Mass det. time= 86.8 min ( 91.8 - 5.0 ) Volume Invert Avail.Storage Storage Description #1 749.50'10,758 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet)(sq-ft)(cubic-feet)(cubic-feet) 749.50 594 0 0 750.00 812 352 352 751.00 1,672 1,242 1,594 752.00 4,802 3,237 4,831 753.00 7,053 5,928 10,758 Device Routing Invert Outlet Devices #1 Primary 747.75'1.5" Vert. Orifice/Grate C= 0.600 #2 Primary 750.85'4.0" x 4.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.10 cfs @ 0.17 hrs HW=750.57' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.10 cfs @ 8.00 fps) 2=Orifice/Grate ( Controls 0.00 cfs) By: BED 6/16/2023 Page: 27 of 34 WR Greenway Trailhead 2-yr Duration=5 min, Inten=5.45 in/hr21EN019 Drainage Calcs Printed 6/27/2023Prepared by SJCA Inc. Page 5HydroCAD® 10.00-26 s/n 07910 © 2020 HydroCAD Software Solutions LLC Pond 1P: Pond Inflow Primary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)3 2 1 0 Inflow Area=1.250 ac Peak Elev=750.57' Storage=957 cf 3.25 cfs 0.10 cfs By: BED 6/16/2023 Page: 28 of 34 WR Greenway Trailhead 10-yr Duration=5 min, Inten=7.34 in/hr21EN019 Drainage Calcs Printed 6/27/2023Prepared by SJCA Inc. Page 6HydroCAD® 10.00-26 s/n 07910 © 2020 HydroCAD Software Solutions LLC Summary for Subcatchment PR2: Prop Disturbed Area Runoff =4.38 cfs @ 0.08 hrs, Volume=0.031 af, Depth= 0.30" Runoff by Rational method, Rise/Fall=1.0/1.0 xTc, Time Span= 0.00-24.00 hrs, dt= 0.01 hrs WR Greenway Trailhead 10-yr Duration=5 min, Inten=7.34 in/hr Area (ac)C Description 1.250 0.49 1.250 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet)(ft/ft) (ft/sec)(cfs) 5.0 Direct Entry, Subcatchment PR2: Prop Disturbed Area Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)4 3 2 1 0 WR Greenway Trailhead 10-yr Duration=5 min, Inten=7.34 in/hr Runoff Area=1.250 ac Runoff Volume=0.031 af Runoff Depth=0.30" Tc=5.0 min C=0.49 4.38 cfs By: BED 6/16/2023 Page: 29 of 34 WR Greenway Trailhead 10-yr Duration=5 min, Inten=7.34 in/hr21EN019 Drainage Calcs Printed 6/27/2023Prepared by SJCA Inc. Page 7HydroCAD® 10.00-26 s/n 07910 © 2020 HydroCAD Software Solutions LLC Summary for Pond 1P: Pond Inflow Area =1.250 ac, 0.00% Impervious, Inflow Depth = 0.30" for 10-yr event Inflow =4.38 cfs @ 0.08 hrs, Volume=0.031 af Outflow =0.10 cfs @ 0.17 hrs, Volume=0.031 af, Atten= 98%, Lag= 5.2 min Primary =0.10 cfs @ 0.17 hrs, Volume=0.031 af Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.01 hrs Peak Elev= 750.82' @ 0.17 hrs Surf.Area= 1,516 sf Storage= 1,305 cf Plug-Flow detention time= 113.8 min calculated for 0.031 af (100% of inflow) Center-of-Mass det. time= 113.9 min ( 118.9 - 5.0 ) Volume Invert Avail.Storage Storage Description #1 749.50'10,758 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet)(sq-ft)(cubic-feet)(cubic-feet) 749.50 594 0 0 750.00 812 352 352 751.00 1,672 1,242 1,594 752.00 4,802 3,237 4,831 753.00 7,053 5,928 10,758 Device Routing Invert Outlet Devices #1 Primary 747.75'1.5" Vert. Orifice/Grate C= 0.600 #2 Primary 750.85'4.0" x 4.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.10 cfs @ 0.17 hrs HW=750.82' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.10 cfs @ 8.35 fps) 2=Orifice/Grate ( Controls 0.00 cfs) By: BED 6/16/2023 Page: 30 of 34 WR Greenway Trailhead 10-yr Duration=5 min, Inten=7.34 in/hr21EN019 Drainage Calcs Printed 6/27/2023Prepared by SJCA Inc. Page 8HydroCAD® 10.00-26 s/n 07910 © 2020 HydroCAD Software Solutions LLC Pond 1P: Pond Inflow Primary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)4 3 2 1 0 Inflow Area=1.250 ac Peak Elev=750.82' Storage=1,305 cf 4.38 cfs 0.10 cfs By: BED 6/16/2023 Page: 31 of 34 WR Greenway Trailhead 100-yr Duration=5 min, Inten=10.13 in/hr21EN019 Drainage Calcs Printed 6/27/2023Prepared by SJCA Inc. Page 9HydroCAD® 10.00-26 s/n 07910 © 2020 HydroCAD Software Solutions LLC Summary for Subcatchment PR2: Prop Disturbed Area Runoff =6.04 cfs @ 0.08 hrs, Volume=0.043 af, Depth= 0.41" Runoff by Rational method, Rise/Fall=1.0/1.0 xTc, Time Span= 0.00-24.00 hrs, dt= 0.01 hrs WR Greenway Trailhead 100-yr Duration=5 min, Inten=10.13 in/hr Area (ac)C Description 1.250 0.49 1.250 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet)(ft/ft) (ft/sec)(cfs) 5.0 Direct Entry, Subcatchment PR2: Prop Disturbed Area Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)6 5 4 3 2 1 0 WR Greenway Trailhead 100-yr Duration=5 min, Inten=10.13 in/hr Runoff Area=1.250 ac Runoff Volume=0.043 af Runoff Depth=0.41" Tc=5.0 min C=0.49 6.04 cfs By: BED 6/16/2023 Page: 32 of 34 WR Greenway Trailhead 100-yr Duration=5 min, Inten=10.13 in/hr21EN019 Drainage Calcs Printed 6/27/2023Prepared by SJCA Inc. Page 10HydroCAD® 10.00-26 s/n 07910 © 2020 HydroCAD Software Solutions LLC Summary for Pond 1P: Pond Inflow Area =1.250 ac, 0.00% Impervious, Inflow Depth = 0.41" for 100-yr event Inflow =6.04 cfs @ 0.08 hrs, Volume=0.043 af Outflow =0.37 cfs @ 0.16 hrs, Volume=0.043 af, Atten= 94%, Lag= 4.8 min Primary =0.37 cfs @ 0.16 hrs, Volume=0.043 af Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.01 hrs Peak Elev= 751.10' @ 0.16 hrs Surf.Area= 1,983 sf Storage= 1,775 cf Plug-Flow detention time= 114.4 min calculated for 0.043 af (100% of inflow) Center-of-Mass det. time= 114.3 min ( 119.3 - 5.0 ) Volume Invert Avail.Storage Storage Description #1 749.50'10,758 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet)(sq-ft)(cubic-feet)(cubic-feet) 749.50 594 0 0 750.00 812 352 352 751.00 1,672 1,242 1,594 752.00 4,802 3,237 4,831 753.00 7,053 5,928 10,758 Device Routing Invert Outlet Devices #1 Primary 747.75'1.5" Vert. Orifice/Grate C= 0.600 #2 Primary 750.85'4.0" x 4.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=0.37 cfs @ 0.16 hrs HW=751.10' (Free Discharge) 1=Orifice/Grate (Orifice Controls 0.11 cfs @ 8.73 fps) 2=Orifice/Grate (Orifice Controls 0.27 cfs @ 2.40 fps) By: BED 6/16/2023 Page: 33 of 34 WR Greenway Trailhead 100-yr Duration=5 min, Inten=10.13 in/hr21EN019 Drainage Calcs Printed 6/27/2023Prepared by SJCA Inc. Page 11HydroCAD® 10.00-26 s/n 07910 © 2020 HydroCAD Software Solutions LLC Pond 1P: Pond Inflow Primary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)6 5 4 3 2 1 0 Inflow Area=1.250 ac Peak Elev=751.10' Storage=1,775 cf 6.04 cfs 0.37 cfs By: BED 6/16/2023 Page: 34 of 34