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HomeMy WebLinkAboutDrainage Report 01-16-19 Geico Parking Lot Expansion Carmel, IN Drainage Report January 15, 2020 Woolpert Geico Parking Lot Expansion, Carmel, IN 2 January 15, 2020 Table of Contents Introduction .............................................................................................................. 3 Pre-Developed Analysis .......................................................................................... 3 Post-Developed Analysis ........................................................................................ 4 Storm Sewer ............................................................................................................. 5 Water Quality ........................................................................................................... 5 Conclusion ................................................................................................................. 5 Exhibits Exhibit 1 – Existing Detention Basin Map Exhibit 2 – Proposed Detention Basin Map Appendices Appendix A – Hydrologic Information Appendix A1 – Soils, FEMA, and Wetlands maps Appendix B – Hydraulic Calculations Appendix B1 – Existing Peak Discharge Calculations Appendix B2 – Proposed Detention Calculations Appendix B3 – Storm Sewer Calculations Appendix B4 – Water Quality Calculations Woolpert Geico Parking Lot Expansion, Carmel, IN 3 January 15, 2020 Introduction This report outlines the storm water management system to serve the parking lot expansion, located at 101 West 103rd Street, Indianapolis, Indiana. The development consists of a 54,300 SF parking lot addition with underground detention and associated storm sewer. Pre-Developed Analysis The approximate 1.35 acre site is located in Carmel, Indiana which is located within Hamilton County. As the proposed development is located within Carmel city limits, the project will be governed by Carmel Stormwater Ordinances. The drainage and stormwater facilities have been designed to be in accordance with these ordinances. The proposed development is contained within a single watershed which ultimately drains to Williams Creek. The proposed site was previously a roundabout intersection up until 2015. The existing site is currently grass with some tree cover. A majority of the site sheet drains southeast where it is collected via inlets on site and within Superior Street. The remaining area sheet drains north where it is intercepted by curb inlets within West 103rd Street. The existing storm system ties into a 24” trunk line within Superior Street that flows south and outlets to a drainage swale along US-31. The drainage swale flows southwest towards I-465 and then directly west where stormwater is ultimately outlet to Williams Creek. A map of the existing and proposed detention basins are provided as Exhibits 1 and 2, respectively. Areas outside of the basin perimeter shown on Exhibits 1 and 2 maintain the existing drainage conditions and have therefore not been included in the allowable release rate or detention calculations. Per coordination with the City of Carmel Engineering Department, a reduction in runoff from the 10 and 100 year storm events in the post-developed conditions to the existing 2 and 10 year release rates of the pre-developed conditions would be acceptable due to the small acreage of the site. Therefore the allowable release rate for the post-developed conditions shall be such that: 10 yr. post-developed ≤ 2 yr. pre-developed 100 yr. post-developed ≤ 10yr. pre-developed The existing and proposed peak discharge rates were determined using the SCS Unit Hydrograph Method and the Type II 24 hour rainfall distribution. PondPack V8i was utilized in order to determine the peak flows. Calculations are provided in Appendix B1. Woolpert Geico Parking Lot Expansion, Carmel, IN 4 January 15, 2020 Table 1: Existing Peak Discharges/Allowable Release Rates 2-Year Peak Discharge (cfs) 10-Year Peak Discharge (cfs) 100-Year Peak Discharge (cfs) Pre-Developed Conditions: 1.07 2.37 5.77 The proposed site lies in Zone X according to FIRM map 18057C0216G from the FEMA database, eff. November 19, 2014. Please see the firm map attached in Appendix A1. The U.S. Department of Agriculture, Soil Conservation Service identifies the watershed to contain two soil classifications. A copy of the Natural Resources Conservation Service (NRCS) can be seen in Appendix A1. The National Wetland Inventory (NWI) indicates that there are no existing wetlands located at the project site. Please see the attached map in Appendix A1. Post-Developed Analysis A majority of the proposed parking lot will sheet drain to 3 separate rain gardens located within the landscape islands, which will serve as a primary source of water quality treatment. The remaining storm runoff will be collected via curb inlets located at the south end of the parking lot. The outlet structures from the rain gardens, as well as the proposed curb inlets, will be connected to the proposed StormTech underground detention system. The underground detention system has been sized to detain runoff from the 100-yr storm event over the entire parking lot expansion. The detention system also includes an isolator row to serve as the secondary form of water quality treatment. In order to meet the allowable release rates, the detention system contains an outlet control structure with a weir wall that spans the manhole. The 10 year release rate is controlled by an 8” orifice located at the base of the weir wall. The top of the weir wall will be at elevation 838.10 so that flows greater than the 10 year storm event can be outlet at a greater rate. The proposed release rates are shown below in Table 2. A new 12” storm pipe will be utilized to outlet the detention system to the 24” trunk line that flows south to the US-31 drainage swale. Pondpack V8i was used to model the post-developed conditions and calculations have been provided in Appendix B2. Table 2: Proposed Peak Discharges 10-Year Peak Discharge (cfs) 100-Year Peak Discharge (cfs) Peak Detention Discharge 1.07 1.77 Results: The proposed, 10-year and 100-year discharge rates are less than the allowable discharge rates. Woolpert Geico Parking Lot Expansion, Carmel, IN 5 January 15, 2020 Storm Sewer The proposed storm sewer network is designed to handle the proposed stormwater runoff from the parking lot expansion in accordance with the Carmel Stormwater Technical Standards Manual. The proposed 10-year hydraulic grade lines are contained within the pipes, and the 100- year hydraulic grade lines are contained within the castings. Stormcad was utilized to size the proposed storm sewer. Calculations are provided in Appendix B3. Water Quality Per the “Carmel Stormwater Technical Standards Manual Chapter 700”, Best Management Practices (BMP’s) must be capable of removing 80% TSS from the stormwater in order to meet water quality standards. To meet this standard, rain gardens in addition to isolation chambers, are used and are sized to appropriately treat the runoff routed through the storm system. The outlet structures with weir walls and orifices are used in the underground detention to stage the appropriate water quality volume at a minimum. Water quality calculations can be seen in Appendix B4. Conclusion The proposed storm sewer system, underground detention, and rain gardens have been designed to be in accordance with Carmel Stormwater Technical Standards Manual and the determination of the review staff. Therefore, no adverse impacts are anticipated as a result of the proposed development. APPENDIX A1 Imagery ©2020 IndianaMap Framework Data, Maxar Technologies, USDA Farm Service Agency, Map data ©2020 200 ft VICINITY MAP LOCATION OF PROPOSED PARKING LOT ADDITION Soil Map—Hamilton County, Indiana Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 1/14/2020 Page 1 of 34420880442091044209404420970442100044210304421060442109044208804420910442094044209704421000442103044210604421090571490571520571550571580571610571640571670571700571730571760571790571820 571490 571520 571550 571580 571610 571640 571670 571700 571730 571760 571790 571820 39° 56' 12'' N 86° 9' 47'' W39° 56' 12'' N86° 9' 33'' W39° 56' 5'' N 86° 9' 47'' W39° 56' 5'' N 86° 9' 33'' 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: 1:1,530 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. 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 1/14/2020 Page 2 of 3 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI UbaA Urban land-Brookston complex, 0 to 2 percent slopes 3.2 36.1% UcfA Urban land-Crosby silt loam complex, fine-loamy subsoil, 0 to 2 percent slopes 5.6 63.9% Totals for Area of Interest 8.8 100.0% Soil Map—Hamilton County, Indiana Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 1/14/2020 Page 3 of 3 USGS The National Map: Orthoimagery. Data refreshed April, 2019. National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250Feet Ü86°10'1.75"W 39°56'15.74"N 86°9'24.29"W 39°55'48.15"N SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOODHAZARD AR EAS Without Base Flood Elevation (BFE)Zone A, V, A99With BFE or Depth Zone AE, AO, AH, VE, AR Regulator y 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 SCREE N Area of Minimal Flood Hazard Zone X Area of Undetermined Flood Hazard Zone D Channel, Culver t, 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 Boundar y 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 ser vices provided by FEMA. This mapwas exported on 1/13/2020 at 9:13:41 AM 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 proper ty location. Geico Parking Lot Expansion U.S. Fish and Wildlife Service, National Standards and Support Team,wetlands_team@fws.gov Wetlands Estuarine and Marine Deepwater Estuarine and Marine Wetland Freshwater Emergent Wetland Freshwater Forested/Shrub Wetland Freshwater Pond Lake Other Riverine January 13, 2020 0 0.1 0.20.05 mi 0 0.15 0.30.075 km 1:7,218 This page was produced by the NWI mapperNational Wetlands Inventory (NWI) This map is for general reference only. The US Fish and Wildlife Service is not responsible for the accuracy or currentness of the base data shown on this map. All wetlands related data should be used in accordance with the layer metadata found on the Wetlands Mapper web site. APPENDIX B1 PARKING LOT EXPANSION GEICO CORPORATE OFFICE EXISTING BASIN MAP 333 North Alabama Street Suite 200 Indianapolis, IN 46204 317.299.7500 FAX: 317.291.5805OVERALLEXISTING BASIN:1.35 ACRESCN = 75TC = 16 MIN. 80484 Geico Parking Expansion 2019 TAB 1/14/2020 Curve Number Calculations Existing Site Proposed Site Cover Type CN Area (ac.) Cover Type CN Area (ac.) Grass B 61 0.03 Grass C 74 0.01 Grass C 74 1.24 Grass D 80 0.15 Impervious 98 0.08 Impervious 98 1.19 Total Area = 1.35 Total Area = 1.35 Weighted CN = 75 Weighted CN = 96 Percent Impervious = 88% Existing PondPack Model Diagram Table of Contents i Table of Contents ********************** MASTER SUMMARY ********************** Watershed....... Master Network Summary ............. 1.01 ********************** TC CALCULATIONS ********************* EXISTING BASIN.. Tc Calcs ........................... 2.01 ********************** CN CALCULATIONS ********************* EXISTING BASIN.. Runoff CN-Area ..................... 3.01 S/N: Bentley PondPack (10.00.027.00) 4:16 PM 1/14/2020 Bentley Systems, Inc. Existing Conditions Calculations File.... G:\DE\Clients\Geico\80484 Geico Parking Expansion 2019\4.0 Disciplines\Civil\Eng\Storm Design\Existing.ppw Name.... Watershed Type.... Master Network Summary Page 1.01 MASTER DESIGN STORM SUMMARY Network Storm Collection: City of Carmel Total Depth Rainfall Return Event in Type RNF ID ------------ ------ ---------------- ---------------- 2 2.6600 Synthetic Curve TypeII 24hr 10 3.8300 Synthetic Curve TypeII 24hr 100 6.4600 Synthetic Curve TypeII 24hr MASTER NETWORK SUMMARY SCS Unit Hydrograph Method (*Node=Outfall; +Node=Diversion;) (Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt) Max Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage Node ID Type Event ac-ft Trun hrs cfs ft ac-ft ----------------- ---- ------ ---------- -- --------- -------- -------- ------------ EXISTING BASIN AREA 2 .084 12.1000 1.07 EXISTING BASIN AREA 10 .173 12.0500 2.37 EXISTING BASIN AREA 100 .413 12.0500 5.77 *OUT 10 JCT 2 .084 12.1000 1.07 *OUT 10 JCT 10 .173 12.0500 2.37 *OUT 10 JCT 100 .413 12.0500 5.77 S/N: Bentley PondPack (10.00.027.00) 4:16 PM 1/14/2020 Bentley Systems, Inc. File.... G:\DE\Clients\Geico\80484 Geico Parking Expansion 2019\4.0 Disciplines\Civil\Eng\Storm Design\Existing.ppw Name.... EXISTING BASIN Type.... Tc Calcs Page 2.01 :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: TIME OF CONCENTRATION CALCULATOR :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: ------------------------------------------------------------------------ Segment #1: Tc: TR-55 Sheet Mannings n .2400 Hydraulic Length 100.00 ft 2yr, 24hr P 2.6600 in Slope .020000 ft/ft Avg.Velocity .11 ft/sec Segment #1 Time: .2609 hrs ------------------------------------------------------------------------ Segment #2: Tc: TR-55 Shallow Hydraulic Length 115.00 ft Slope .020000 ft/ft Unpaved Avg.Velocity 2.28 ft/sec Segment #2 Time: .0140 hrs ------------------------------------------------------------------------ ========================= Total Tc: .2749 hrs ========================= S/N: Bentley PondPack (10.00.027.00) 4:16 PM 1/14/2020 Bentley Systems, Inc. File.... G:\DE\Clients\Geico\80484 Geico Parking Expansion 2019\4.0 Disciplines\Civil\Eng\Storm Design\Existing.ppw Name.... EXISTING BASIN Type.... Tc Calcs Page 2.02 ------------------------------------------------------------------------ Tc Equations used... ------------------------------------------------------------------------ ==== SCS TR-55 Sheet Flow ============================================== Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4)) Where: Tc = Time of concentration, hrs n = Mannings n Lf = Flow length, ft P = 2yr, 24hr Rain depth, inches Sf = Slope, % ==== SCS TR-55 Shallow Concentrated Flow =============================== Unpaved surface: V = 16.1345 * (Sf**0.5) Paved surface: V = 20.3282 * (Sf**0.5) Tc = (Lf / V) / (3600sec/hr) Where: V = Velocity, ft/sec Sf = Slope, ft/ft Tc = Time of concentration, hrs Lf = Flow length, ft S/N: Bentley PondPack (10.00.027.00) 4:16 PM 1/14/2020 Bentley Systems, Inc. File.... G:\DE\Clients\Geico\80484 Geico Parking Expansion 2019\4.0 Disciplines\Civil\Eng\Storm Design\Existing.ppw Name.... EXISTING BASIN Type.... Runoff CN-Area Page 3.01 RUNOFF CURVE NUMBER DATA :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -------------------------------------------------------------------------- Impervious Area Adjustment Adjusted Soil/Surface Description CN acres %C %UC CN -------------------------------- ---- --------- ----- ----- ------ Existing Grass Area 75 1.350 75.00 COMPOSITE AREA & WEIGHTED CN ---> 1.350 75.00 (75) ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: S/N: Bentley PondPack (10.00.027.00) 4:16 PM 1/14/2020 Bentley Systems, Inc. APPENDIX B2 WEST 103rd STREETSUPERIOR STREETSTR 1.3:0.27 ACc = 0.83TC = 5 MIN.STR 2.1:0.12 ACc = 0.85TC = 5 MIN.STR 2.2:0.11 ACc = 0.72TC = 5 MIN.STR 2.3:0.06 ACc = 0.74TC = 5 MIN.STR 3.2:0.30 ACc = 0.76TC = 5 MIN.STR 3.3:0.40 ACc = 0.76TC = 5 MIN.STR 3.1:0.06 ACc = 0.55TC = 5 MIN.PARKING LOT EXPANSION GEICO CORPORATE OFFICE PROPOSED BASIN MAP 333 North Alabama Street Suite 200 Indianapolis, IN 46204 317.299.7500 FAX: 317.291.5805OVERALLPROPOSED BASIN:1.35 ACRESCN = 96 Proposed Conditions PondPack Model Diagram Table of Contents i Table of Contents ********************** MASTER SUMMARY ********************** Watershed....... Master Network Summary ............. 1.01 ********************** TC CALCULATIONS ********************* PROPOSED........ Tc Calcs ........................... 2.01 ********************** CN CALCULATIONS ********************* PROPOSED........ Runoff CN-Area ..................... 3.01 ******************** OUTLET STRUCTURES ********************* Outlet 1........ Outlet Input Data .................. 4.01 Individual Outlet Curves ........... 4.04 Composite Rating Curve ............. 4.13 S/N: Bentley PondPack (10.00.027.00) 4:25 PM 1/14/2020 Bentley Systems, Inc. Proposed Conditions Calculations File.... G:\DE\Clients\Geico\80484 Geico Parking Expansion 2019\4.0 Disciplines\Civil\Eng\Storm Design\Reduced Chambers.ppw Name.... Watershed Type.... Master Network Summary Page 1.01 MASTER DESIGN STORM SUMMARY Network Storm Collection: City of Carmel Total Depth Rainfall Return Event in Type RNF ID ------------ ------ ---------------- ---------------- 10 3.8300 Synthetic Curve TypeII 24hr 100 6.4600 Synthetic Curve TypeII 24hr MASTER NETWORK SUMMARY SCS Unit Hydrograph Method (*Node=Outfall; +Node=Diversion;) (Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt) Max Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage Node ID Type Event ac-ft Trun hrs cfs ft ac-ft ----------------- ---- ------ ---------- -- --------- -------- -------- ------------ *OUT 10 JCT 10 .378 12.1500 1.07 *OUT 10 JCT 100 .672 12.1500 1.77 POND 10 IN POND 10 .379 11.9000 6.39 POND 10 IN POND 100 .673 11.9000 11.02 POND 10 OUT POND 10 .378 12.1500 1.07 838.07 .163 POND 10 OUT POND 100 .672 12.1500 1.77 839.58 .285 PROPOSED AREA 10 .379 11.9000 6.39 PROPOSED AREA 100 .673 11.9000 11.02 S/N: Bentley PondPack (10.00.027.00) 4:25 PM 1/14/2020 Bentley Systems, Inc. File.... G:\DE\Clients\Geico\80484 Geico Parking Expansion 2019\4.0 Disciplines\Civil\Eng\Storm Design\Reduced Chambers.ppw Name.... PROPOSED Type.... Tc Calcs Page 2.01 :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: TIME OF CONCENTRATION CALCULATOR :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: ------------------------------------------------------------------------ Segment #1: Tc: User Defined Segment #1 Time: .0830 hrs ------------------------------------------------------------------------ ========================= Total Tc: .0830 hrs Calculated Tc < Min.Tc: Use Minimum Tc... Use Tc = .0833 hrs ========================= S/N: Bentley PondPack (10.00.027.00) 4:25 PM 1/14/2020 Bentley Systems, Inc. File.... G:\DE\Clients\Geico\80484 Geico Parking Expansion 2019\4.0 Disciplines\Civil\Eng\Storm Design\Reduced Chambers.ppw Name.... PROPOSED Type.... Runoff CN-Area Page 3.01 RUNOFF CURVE NUMBER DATA :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -------------------------------------------------------------------------- Impervious Area Adjustment Adjusted Soil/Surface Description CN acres %C %UC CN -------------------------------- ---- --------- ----- ----- ------ Proposed Parking Expansion 96 1.350 96.00 COMPOSITE AREA & WEIGHTED CN ---> 1.350 96.00 (96) ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: S/N: Bentley PondPack (10.00.027.00) 4:25 PM 1/14/2020 Bentley Systems, Inc. File.... G:\DE\Clients\Geico\80484 Geico Parking Expansion 2019\4.0 Disciplines\Civil\Eng\Storm Design\Reduced Chambers.ppw Name.... Outlet 1 Type.... Outlet Input Data Page 4.01 REQUESTED POND WS ELEVATIONS: Min. Elev.= 836.35 ft Increment = .10 ft Max. Elev.= 839.85 ft ********************************************** OUTLET CONNECTIVITY ********************************************** ---> Forward Flow Only (UpStream to DnStream) <--- Reverse Flow Only (DnStream to UpStream) <---> Forward and Reverse Both Allowed Structure No. Outfall E1, ft E2, ft ----------------- ---- ------- --------- --------- Orifice-Circular O0 ---> C0 836.350 839.850 Weir-Rectangular W0 ---> C0 838.100 839.850 Culvert-Circular C0 ---> TW 836.350 839.850 TW SETUP, DS Channel S/N: Bentley PondPack (10.00.027.00) 4:25 PM 1/14/2020 Bentley Systems, Inc. File.... G:\DE\Clients\Geico\80484 Geico Parking Expansion 2019\4.0 Disciplines\Civil\Eng\Storm Design\Reduced Chambers.ppw Name.... Outlet 1 Type.... Outlet Input Data Page 4.02 OUTLET STRUCTURE INPUT DATA Structure ID = O0 Structure Type = Orifice-Circular ------------------------------------ # of Openings = 1 Invert Elev. = 836.35 ft Diameter = .6700 ft Orifice Coeff. = .600 Structure ID = W0 Structure Type = Weir-Rectangular ------------------------------------ # of Openings = 1 Crest Elev. = 838.10 ft Weir Length = 4.00 ft Weir Coeff. = 3.300000 Weir TW effects (Use adjustment equation) S/N: Bentley PondPack (10.00.027.00) 4:25 PM 1/14/2020 Bentley Systems, Inc. File.... G:\DE\Clients\Geico\80484 Geico Parking Expansion 2019\4.0 Disciplines\Civil\Eng\Storm Design\Reduced Chambers.ppw Name.... Outlet 1 Type.... Outlet Input Data Page 4.03 OUTLET STRUCTURE INPUT DATA Structure ID = C0 Structure Type = Culvert-Circular ------------------------------------ No. Barrels = 1 Barrel Diameter = 1.0000 ft Upstream Invert = 836.35 ft Dnstream Invert = 836.02 ft Horiz. Length = 15.00 ft Barrel Length = 15.00 ft Barrel Slope = .02200 ft/ft OUTLET CONTROL DATA... Mannings n = .1100 Ke = .2000 (forward entrance loss) Kb = 2.239117 (per ft of full flow) Kr = .2000 (reverse entrance loss) HW Convergence = .001 +/- ft INLET CONTROL DATA... Equation form = 1 Inlet Control K = .0045 Inlet Control M = 2.0000 Inlet Control c = .03170 Inlet Control Y = .6900 T1 ratio (HW/D) = 1.084 T2 ratio (HW/D) = 1.186 Slope Factor = -.500 Use unsubmerged inlet control Form 1 equ. below T1 elev. Use submerged inlet control Form 1 equ. above T2 elev. In transition zone between unsubmerged and submerged inlet control, interpolate between flows at T1 & T2... At T1 Elev = 837.43 ft ---> Flow = 2.75 cfs At T2 Elev = 837.54 ft ---> Flow = 3.14 cfs S/N: Bentley PondPack (10.00.027.00) 4:25 PM 1/14/2020 Bentley Systems, Inc. Project: Chamber Model - SC-740 Units -Imperial Number of chambers - 164 Voids in the stone (porosity) - 40 % Base of Stone Elevation - 836.35 ft Amount of Stone Above Chambers - 6 in Amount of Stone Below Chambers - 6 in Area of system -6100 sf Min. Area - Height of System Incremental Single Chamber Incremental Total Chamber Incremental Stone Incremental Ch & St Cumulative Chamber Elevation (inches)(cubic feet)(cubic feet)(cubic feet)(cubic feet)(cubic feet)(feet) 42 0.00 0.00 203.33 203.33 13061.56 839.85 41 0.00 0.00 203.33 203.33 12858.23 839.77 40 0.00 0.00 203.33 203.33 12654.90 839.68 39 0.00 0.00 203.33 203.33 12451.56 839.60 38 0.00 0.00 203.33 203.33 12248.23 839.52 37 0.00 0.00 203.33 203.33 12044.90 839.43 36 0.05 9.02 199.73 208.74 11841.56 839.35 35 0.16 26.72 192.65 219.36 11632.82 839.27 34 0.28 46.24 184.84 231.08 11413.45 839.18 33 0.60 99.05 163.71 262.76 11182.38 839.10 32 0.80 131.48 150.74 282.22 10919.61 839.02 31 0.95 155.91 140.97 296.88 10637.39 838.93 30 1.07 176.22 132.85 309.07 10340.51 838.85 29 1.18 193.60 125.89 319.49 10031.45 838.77 28 1.27 207.57 120.31 327.87 9711.95 838.68 27 1.36 222.22 114.44 336.67 9384.08 838.60 26 1.45 238.47 107.94 346.42 9047.41 838.52 25 1.52 250.06 103.31 353.37 8701.00 838.43 24 1.58 259.50 99.53 359.03 8347.63 838.35 23 1.64 269.33 95.60 364.93 7988.60 838.27 22 1.70 278.72 91.85 370.57 7623.66 838.18 21 1.75 287.48 88.34 375.82 7253.10 838.10 20 1.80 295.66 85.07 380.73 6877.27 838.02 19 1.85 304.22 81.65 385.87 6496.54 837.93 18 1.89 310.47 79.15 389.61 6110.68 837.85 17 1.93 317.18 76.46 393.64 5721.07 837.77 16 1.97 323.90 73.77 397.67 5327.43 837.68 15 2.01 329.63 71.48 401.11 4929.75 837.60 14 2.04 335.38 69.18 404.56 4528.64 837.52 13 2.07 340.29 67.22 407.51 4124.08 837.43 12 2.10 345.21 65.25 410.46 3716.57 837.35 11 2.13 349.61 63.49 413.10 3306.12 837.27 10 2.15 353.23 62.04 415.27 2893.01 837.18 9 2.18 357.04 60.52 417.56 2477.74 837.10 8 2.20 360.53 59.12 419.65 2060.19 837.02 7 2.21 362.00 58.53 420.53 1640.53 836.93 6 0.00 0.00 203.33 203.33 1220.00 836.85 5 0.00 0.00 203.33 203.33 1016.67 836.77 4 0.00 0.00 203.33 203.33 813.33 836.68 3 0.00 0.00 203.33 203.33 610.00 836.60 2 0.00 0.00 203.33 203.33 406.67 836.52 1 0.00 0.00 203.33 203.33 203.33 836.43 StormTech SC-740 Cumulative Storage Volumes Geico Parking Expansion - Full Detention 5544 sf min. area Include Perimeter Stone in Calculations Click Here for Metric APPENDIX B3 Project: Chamber Model - SC-740 Units -Imperial Number of chambers - 52 Voids in the stone (porosity) - 40 % Base of Stone Elevation - 836.35 ft Amount of Stone Above Chambers - 6 in Amount of Stone Below Chambers - 6 in Area of system -2000 sf Min. Area - Height of System Incremental Single Chamber Incremental Total Chamber Incremental Stone Incremental Ch & St Cumulative Chamber Elevation (inches)(cubic feet)(cubic feet)(cubic feet)(cubic feet)(cubic feet)(feet) 42 0.00 0.00 66.67 66.67 4233.67 839.85 41 0.00 0.00 66.67 66.67 4167.00 839.77 40 0.00 0.00 66.67 66.67 4100.33 839.68 39 0.00 0.00 66.67 66.67 4033.67 839.60 38 0.00 0.00 66.67 66.67 3967.00 839.52 37 0.00 0.00 66.67 66.67 3900.33 839.43 36 0.05 2.86 65.52 68.38 3833.67 839.35 35 0.16 8.47 63.28 71.75 3765.28 839.27 34 0.28 14.66 60.80 75.46 3693.53 839.18 33 0.60 31.41 54.10 85.51 3618.07 839.10 32 0.80 41.69 49.99 91.68 3532.56 839.02 31 0.95 49.43 46.89 96.33 3440.88 838.93 30 1.07 55.87 44.32 100.19 3344.55 838.85 29 1.18 61.39 42.11 103.50 3244.36 838.77 28 1.27 65.81 40.34 106.16 3140.86 838.68 27 1.36 70.46 38.48 108.94 3034.71 838.60 26 1.45 75.61 36.42 112.03 2925.76 838.52 25 1.52 79.29 34.95 114.24 2813.73 838.43 24 1.58 82.28 33.75 116.04 2699.49 838.35 23 1.64 85.40 32.51 117.91 2583.46 838.27 22 1.70 88.37 31.32 119.69 2465.55 838.18 21 1.75 91.15 30.21 121.36 2345.86 838.10 20 1.80 93.75 29.17 122.91 2224.50 838.02 19 1.85 96.46 28.08 124.54 2101.59 837.93 18 1.89 98.44 27.29 125.73 1977.04 837.85 17 1.93 100.57 26.44 127.01 1851.31 837.77 16 1.97 102.70 25.59 128.29 1724.31 837.68 15 2.01 104.52 24.86 129.38 1596.02 837.60 14 2.04 106.34 24.13 130.47 1466.64 837.52 13 2.07 107.90 23.51 131.41 1336.17 837.43 12 2.10 109.46 22.88 132.34 1204.77 837.35 11 2.13 110.85 22.33 133.18 1072.43 837.27 10 2.15 112.00 21.87 133.87 939.25 837.18 9 2.18 113.21 21.38 134.59 805.38 837.10 8 2.20 114.31 20.94 135.26 670.79 837.02 7 2.21 114.78 20.75 135.54 535.54 836.93 6 0.00 0.00 66.67 66.67 400.00 836.85 5 0.00 0.00 66.67 66.67 333.33 836.77 4 0.00 0.00 66.67 66.67 266.67 836.68 3 0.00 0.00 66.67 66.67 200.00 836.60 2 0.00 0.00 66.67 66.67 133.33 836.52 1 0.00 0.00 66.67 66.67 66.67 836.43 StormTech SC-740 Cumulative Storage Volumes Geico Parking Expansion - Water Quality 1758 sf min. area Include Perimeter Stone in Calculations Click Here for Metric 4233.67 cu. ft > 4,131.1 cu.ft. required for storm water quality treatment APPENDIX B4 Prepared by Trent Burchett 1/14/2020Page 1Geico Parking Lot ExpansionSTR #: 1.3 STR #: 2.1 STR #: 2.2 STR #: 2.3Cover Type C Value Area (ac.) Cover Type C Value Area (ac.) Cover Type C Value Area (ac.) Cover Type C Value Area (ac.)Grass 0.25 0.01 Grass 0.25 0.00 Grass 0.25 0.03 Grass 0.25 0.00Pavement 0.850.26Pavement 0.850.12Pavement 0.850.09Pavement 0.850.05Roof 0.90 0.00 Roof 0.90 0.00 Roof 0.90 0.00 Roof 0.90 0.00Rain Garden 0.15 0.00 Rain Garden 0.15 0.00 Rain Garden 0.15 0.00 Rain Garden 0.15 0.01Total Area = 0.27 Total Area = 0.12 Total Area = 0.11 Total Area = 0.06Weighted C Value = 0.83 Weighted C Value = 0.85 Weighted C Value = 0.72 Weighted C Value = 0.74STR #: 3.1 STR #: 3.2 STR #: 3.3Cover Type C Value Area (ac.) Cover Type C Value Area (ac.) Cover Type C Value Area (ac.)Grass 0.25 0.00 Grass 0.25 0.00 Grass 0.25 0.06Pavement 0.850.03Pavement 0.850.26Pavement 0.850.34Roof 0.90 0.00 Roof 0.90 0.00 Roof 0.90 0.00Rain Garden 0.15 0.03 Rain Garden 0.15 0.04 Rain Garden 0.15 0.01Total Area = 0.06 Total Area = 0.30 Total Area = 0.40Weighted C Value = 0.55 Weighted C Value = 0.76 Weighted C Value = 0.76 Proposed StormCAD Network Diagram FlexTable: Catch Basin Table Hydraulic Grade Line (In) (ft) Flow (Captured) (cfs) Inflow (Wet) Collection <Count> Elevation (Invert) (ft) Elevation (Rim) (ft) LabelID 837.810.500837.51841.702.272 837.720.630837.20841.052.173 839.470.280839.25843.002.375 837.551.380836.97840.711.376 839.341.410838.75842.503.278 839.110.200838.49843.503.179 840.981.880840.25844.003.381 Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1/14/2020 Bentley StormCAD CONNECT Edition [10.01.00.70] Bentley Systems, Inc. Haestad Methods Solution CenterGeico Drainage.stsw 10 Year FlexTable: Catchment TableFlow (Total Out)(cfs)Runoff MethodArea (User Defined)(acres)Time of Concentration(min)Runoff Coefficient (Rational)Outflow ElementLabelID0.63Rational Method0.1205.0000.8502.1CM-2.1900.50Rational Method0.1105.0000.7302.2CM-2.2910.28Rational Method0.0605.0000.7602.3CM-2.3921.88Rational Method0.4005.0000.7603.3CM-3.3950.20Rational Method0.0605.0000.5503.1CM-3.1961.41Rational Method0.3005.0000.7603.2CM-3.2971.38Rational Method0.2705.0000.8301.3CM-1.3100Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-16661/14/2020Bentley StormCAD CONNECT Edition[10.01.00.70]Bentley Systems, Inc. Haestad Methods Solution CenterGeico Drainage.stsw10 Year FlexTable: Conduit TableSystem Flow Time(min)Hydraulic Grade Line (Out)(ft)Hydraulic Grade Line (In)(ft)Flow / Capacity (Design)(%)Capacity (Full Flow)(cfs)Flow(cfs)Velocity(ft/s)Length (Unified)(ft)Manning's nDiameter(in)Slope (Calculated)(ft/ft)Invert (Stop)(ft)Invert (Start)(ft)Stop NodeStart NodeLabelID5.274837.47837.7253.72.081.122.6949.90.01312.00.003837.03837.202.02.1CO-2.1835.000837.72837.8119.52.540.502.5141.20.01312.00.005837.30837.512.12.2CO-2.2845.000839.38839.478.43.330.282.588.00.01312.00.009839.18839.252.02.3CO-2.3855.000837.35837.5566.22.091.382.8435.00.01312.00.003836.85836.971.21.3CO-1.3865.265838.97839.1178.02.051.602.8818.20.01312.00.003838.43838.493.03.1CO-3.1875.000839.11839.3466.72.111.412.8745.60.01312.00.004838.59838.753.13.2CO-3.2885.000840.42840.9889.22.101.883.03117.60.01312.00.003839.84840.253.03.3CO-3.3895.583836.85836.9067.22.061.382.813.00.01312.00.003836.35836.36O-22.0CO-2.0945.648837.10837.1691.73.733.423.453.00.01315.00.003836.35836.36O-33.0CO-3.0995.205836.85836.9066.82.061.372.803.00.01312.00.003836.35836.36O-11.2CO-1.2102Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-16661/14/2020Bentley StormCAD CONNECT Edition[10.01.00.70]Bentley Systems, Inc. Haestad Methods Solution CenterGeico Drainage.stsw10 Year FlexTable: Manhole TableHydraulic Grade Line (In)(ft)Flow (Total Out)(cfs)Flow (Local In)(cfs)Elevation (Invert)(ft)Elevation (Rim)(ft)Elevation (Ground)(ft)LabelID836.901.380.00836.36842.80842.802.074837.163.420.00836.36844.57844.573.080836.901.370.00836.36841.86841.861.282Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-16661/14/2020Bentley StormCAD CONNECT Edition[10.01.00.70]Bentley Systems, Inc. Haestad Methods Solution CenterGeico Drainage.stsw10 Year FlexTable: Outfall TableSystem Flow Time(min)Flow (Total Out)(cfs)Hydraulic Grade(ft)Elevation (Invert)(ft)Elevation (Ground)(ft)LabelID5.6001.38836.85836.35842.60O-2935.6623.42837.10836.35844.57O-3985.2231.37836.85836.35841.80O-1101Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-16661/14/2020Bentley StormCAD CONNECT Edition[10.01.00.70]Bentley Systems, Inc. Haestad Methods Solution CenterGeico Drainage.stsw10 Year FlexTable: Catch Basin Table Hydraulic Grade Line (In) (ft) Flow (Captured) (cfs) Inflow (Wet) Collection <Count> Elevation (Invert) (ft) Elevation (Rim) (ft) LabelID 837.890.740837.51841.702.272 837.860.940837.20841.052.173 839.520.420839.25843.002.375 837.722.060836.97840.711.376 839.522.100838.75842.503.278 839.290.300838.49843.503.179 841.392.790840.25844.003.381 Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1/14/2020 Bentley StormCAD CONNECT Edition [10.01.00.70] Bentley Systems, Inc. Haestad Methods Solution CenterGeico Drainage.stsw 100 Year FlexTable: Catchment TableFlow (Total Out)(cfs)Runoff MethodArea (User Defined)(acres)Time of Concentration(min)Runoff Coefficient (Rational)Outflow ElementLabelID0.94Rational Method0.1205.0000.8502.1CM-2.1900.74Rational Method0.1105.0000.7302.2CM-2.2910.42Rational Method0.0605.0000.7602.3CM-2.3922.79Rational Method0.4005.0000.7603.3CM-3.3950.30Rational Method0.0605.0000.5503.1CM-3.1962.10Rational Method0.3005.0000.7603.2CM-3.2972.06Rational Method0.2705.0000.8301.3CM-1.3100Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-16661/14/2020Bentley StormCAD CONNECT Edition[10.01.00.70]Bentley Systems, Inc. Haestad Methods Solution CenterGeico Drainage.stsw100 Year FlexTable: Conduit TableSystem Flow Time(min)Hydraulic Grade Line (Out)(ft)Hydraulic Grade Line (In)(ft)Flow / Capacity (Design)(%)Capacity (Full Flow)(cfs)Flow(cfs)Velocity(ft/s)Length (Unified)(ft)Manning's nDiameter(in)Slope (Calculated)(ft/ft)Invert (Stop)(ft)Invert (Start)(ft)Stop NodeStart NodeLabelID5.245837.58837.8680.02.081.662.9449.90.01312.00.003837.03837.202.02.1CO-2.1835.000837.86837.8929.02.540.742.8141.20.01312.00.005837.30837.512.12.2CO-2.2845.000839.42839.5212.63.330.422.908.00.01312.00.009839.18839.252.02.3CO-2.3855.000837.46837.7298.72.092.063.0335.00.01312.00.003836.85836.971.21.3CO-1.3865.249839.09839.29116.32.052.383.0318.20.01312.00.003838.43838.493.03.1CO-3.1875.000839.29839.5299.42.112.103.0645.60.01312.00.004838.59838.753.13.2CO-3.2885.000840.56841.39132.92.102.793.56117.60.01312.00.003839.84840.253.03.3CO-3.3895.528836.96837.03100.32.062.062.993.00.01312.00.003836.35836.36O-22.0CO-2.0945.551837.27837.35137.03.735.114.163.00.01315.00.003836.35836.36O-33.0CO-3.0995.192836.96837.0299.62.062.052.993.00.01312.00.003836.35836.36O-11.2CO-1.2102Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-16661/14/2020Bentley StormCAD CONNECT Edition[10.01.00.70]Bentley Systems, Inc. Haestad Methods Solution CenterGeico Drainage.stsw100 Year FlexTable: Manhole TableHydraulic Grade Line (In)(ft)Flow (Total Out)(cfs)Flow (Local In)(cfs)Elevation (Invert)(ft)Elevation (Rim)(ft)Elevation (Ground)(ft)LabelID837.032.060.00836.36842.80842.802.074837.355.110.00836.36844.57844.573.080837.022.050.00836.36841.86841.861.282Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-16661/14/2020Bentley StormCAD CONNECT Edition[10.01.00.70]Bentley Systems, Inc. Haestad Methods Solution CenterGeico Drainage.stsw100 Year FlexTable: Outfall TableSystem Flow Time(min)Flow (Total Out)(cfs)Hydraulic Grade(ft)Elevation (Invert)(ft)Elevation (Ground)(ft)LabelID5.5442.06836.96836.35842.60O-2935.5635.11837.27836.35844.57O-3985.2092.05836.96836.35841.80O-1101Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-16661/14/2020Bentley StormCAD CONNECT Edition[10.01.00.70]Bentley Systems, Inc. Haestad Methods Solution CenterGeico Drainage.stsw100 Year THE MAXIMUM FLOW CAPTURED BY AN INLET WITH AN R-3246 CASTING IS 1.38 CFS. (STRUCTURE 1.3) 3130 Verona Avenue • Buford, GA 30518 (866) 888-8479 / (770) 932-2443 • Fax: (770) 932-2490 © Nyloplast Inlet Capacity Charts June 2012 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85 0.90 0.95 1.00 1.05 1.10Capacity (cfs)Head (ft) Nyloplast 18" Dome Grate Inlet Capacity Chart THE MAXIMUM FLOW CAPTURED BY A NYLOPLAST INLET WITH AN 18" CASTING IS 1.88 CFS. (STRUCTURE 3.3)