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Stormwater900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com STORMWATER MANAGEMENT NARRATIVE PROPOSED BUNK HOUSE SLOTE RESIDENCE TOWN OF QUEENSBURY, NY Prepared by: Environmental Design Partnership Clifton Park, NY 12065 DECEMBER 2021 Stormwater Management Narrative 20 Burnt Ridge Road Town of Queensbury, New York 900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com 1.0 INTRODUCTION The applicant is proposing to construct a 1,000 sf bunk house with attached 200 sf screened porch on an approximate 1.0 acre parcel. The project site is located to the west side of Burnt Ridge Road off of Old Assembly Point Rd north of the intersection with Ridge Rd, in the Town of Queensbury, New York. The proposed redevelopment will result in total soil disturbance on the order of 5,700 square feet and will increase existing impervious by 1,200 square feet for a total of approximately 9,134 square feet. A stormwater management system will be designed to provide reduction of the stormwater runoff rates and volumes in accordance with the Town of Queensbury Stormwater Management Regulations. The proposed project includes less than 1 acre of disturbance therefore is not required to gain coverage under NYSDEC SPDES permit. The proposed stormwater management system will include 2 rain gardens with a total storage volume on the order of 177 cubic feet. This narrative presents a review of the design concepts and parameters of the stormwater management system for the proposed site improvements. The purpose of the stormwater management narrative is to assure that changes in the surface runoff characteristics, as a result of the proposed construction, will not adversely impact adjacent or downstream properties. On-site stormwater management will be implemented in accordance with the Town of Queensbury Stormwater Management Regulations, Chapter 147 of the Town Code, to accommodate runoff rate and volumes. 2.0 EXISTING SITE CONDITIONS The existing site consists of a single-family house, detached garage, several sheds, paved driveway and lawn area. The runoff flows to the north of the property eventually running into Lake George. The topography of the site is steep with the majority of slopes being greater than 15%. 2.1 Soil and Groundwater Conditions The NRCS Web Soil Survey identifies the primary soil groups within the area of the proposed site improvements to be BeC (Bice-Woodstock). The Soil Survey identifies BeE soil series as Hydrologic Soil Group (HSG) “D”. A hydraulic model of the preexisting site was prepared using the Hydrocad program. One (1) subcatchment was used to represent the existing drainage characteristics, see Figure 2. The existing parameters of topography, vegetation, slope and soil type are all incorporated into the predevelopment hydraulic model, the entire drainage area was modeled as “woods good” for the predevelopment model. The results for the existing condition model are summarized later in this report and have been included in Appendix A. Stormwater Management Narrative 20 Burnt Ridge Road Town of Queensbury, New York 900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com 3.0 POST DEVELOPMENT STORMWATER ANALYSIS Site improvements to the property consist of construction of a 1,000 sf bunk house with attached 200 sf screened in porch, construction of a new paved driveway and construction of retaining walls. Stormwater management practices have been designed to provide filtration, infiltration capacity and attenuation of stormwater runoff from the site area. The proposed stormwater management system shall consist of two (2) rain gardens. The rains garden have been designed to collect, attenuate and infiltrate the stormwater runoff from the structures. The rain gardens are designed to provide attenuation and infiltration of the contributing stormwater runoff. The rain garden has been designed with a planting soil media and a stone reservoir in order to allow for filtering of the contributing stormwater runoff. The rain gardens have been sized accordingly to provide attenuation and infiltration of stormwater runoff for storms up to and including the 25-year design storm. Overflow from the rain garden will be directed to Lake George to follow pre development site conditions. 3.1 Town of Queensbury Stormwater Regulations The project consists of construction of a structure within 50 feet of 15% slopes and therefore, according the Chapter 147 of the town code, is considered a major project. The proposed stormwater management has been designed in accordance with the Queensbury Town Code which requires that the volume of runoff for a ten-year storm shall be maintained after development and that the peak rate of runoff shall not be increased for the 25-year storm. The following tables summarize the stormwater modeling results. Table 1: 10-Year (3.52 inch) Design Storm Runoff Volume Design Point Predevelopment Runoff Volume (cf) Post-Development Runoff Volume (cf) 1 1,848 1,837 Table 2: 25-Year (4.27 inch) Design Storm Runoff Rate Design Point Predevelopment Runoff Rate (cfs) Post-Development Runoff Rate (cfs) 1 1.17 0.96 Stormwater Management Narrative 20 Burnt Ridge Road Town of Queensbury, New York 900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com 4.0 SUMMARY Development of the proposed site has changed the stormwater drainage characteristics of the site; impervious area was added and the site was re-graded to support the improvements. Changes to the stormwater drainage characteristics of the site have been evaluated in accordance with the Queensbury Town Code. The proposed stormwater management system will comply with the recommendations in these standards related to runoff volume and flow rate reduction. Through the implementation of acceptable stormwater management practices, the proposed project will not adversely affect adjacent or downstream properties. Prepared by: Connor DeMyer Reviewed by: Nick Zeglen, P.E. Stormwater Management Narrative 20 Burnt Ridge Road Town of Queensbury, New York 900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com 5.0 REFERENCES HydroCAD version 6.00, Applied Microcomputer Systems, Chocura, New Hampshire. NYSDEC, 1990. “Technical and Operational Guidance Series (5.1.8) Stormwater Management Guidelines for New Development”, New York State Department of Environmental Conservation, Division of Water. NYSDEC, 1992. “Reducing the Impacts of Stormwater Runoff from New Development”, New York State Department of Environmental Conservation, Division of Water. NYSDEC, 2015. “New York State Stormwater Management Design Manual”, Center for Watershed Protection, Ellicott City, MD. Rawls, W.J., Brakensiek, D.L., and Saxton, K. E., 1982. “Estimation of Soil Properties”, Transactions of the American Society of Agricultural Engineers, Vol. 25, No. J, pp. 1316-1320. S.C.S., 1982. “TR-20 Project Formulation-Hydrology, Technical Release No. 20”, U.S. Department of Agriculture, Soil Conservation Service, Hydrology Unit Division of Engineering. Stormwater Management Narrative 20 Burnt Ridge Road Town of Queensbury, New York 900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com Figure 1: Site Location SITE LOCATION Stormwater Management Narrative Bay Parkway. Town of Queensbury, New York 900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com Appendix A USDA Soil Survey Soil Map—Warren County, New York Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/28/2021 Page 1 of 34811700481173048117604811790481182048118504811700481173048117604811790481182048118504811880608820608850608880608910608940608970609000609030609060609090 608820 608850 608880 608910 608940 608970 609000 609030 609060 609090 43° 27' 6'' N 73° 39' 18'' W43° 27' 6'' N73° 39' 5'' W43° 27' 0'' N 73° 39' 18'' W43° 27' 0'' N 73° 39' 5'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 18N WGS84 0 50 100 200 300 Feet 0 15 30 60 90 Meters Map Scale: 1:1,300 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: Warren County, New York Survey Area Data: Version 21, Sep 1, 2021 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jun 10, 2015—Mar 29, 2017 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—Warren County, New York Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/28/2021 Page 2 of 3 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI BeC Bice-Woodstock very bouldery fine sandy loams, sloping 1.8 39.2% BeE Bice-Woodstock very bouldery fine sandy loams, steep 2.8 60.0% W Water 0.0 0.8% Totals for Area of Interest 4.6 100.0% Soil Map—Warren County, New York Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/28/2021 Page 3 of 3 Stormwater Management Narrative Bay Parkway. Town of Queensbury, New York 900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com Appendix B Predevelopment Stormwater Modeling Calculations 430420420410410400 390380370 380390400 1" = 30'PREDEVELOPMENTS-6PROPOSED SITE IMPROVEMENTS FOR 20 BURNT RIDGE ROAD TOWN OF QUEENSBURY JUNE 14, 2021 SLOTE RESIDENCE WARREN COUNTY, NEW YORK TAX MAP. No. 239.16-1-9900 Route 146 Clifton Park, New York 12065 edpllp.com(518) 371-7621 E N V I R O N M E N T A L D E S I G N P A R T N E R S H I P, L L P. 1S (new Subcat) 2L Routing Diagram for predevelop Prepared by {enter your company name here}, Printed 12/28/2021 HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Subcat Reach Pond Link predevelop Printed 12/28/2021Prepared by {enter your company name here} Page 2HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (sq-ft) CN Description (subcatchment-numbers) 15,342 77 Woods, Good, HSG D (1S) 15,342 77 TOTAL AREA predevelop Printed 12/28/2021Prepared by {enter your company name here} Page 3HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (sq-ft) Soil Group Subcatchment Numbers 0 HSG A 0 HSG B 0 HSG C 15,342 HSG D 1S 0 Other 15,342 TOTAL AREA predevelop Printed 12/28/2021Prepared by {enter your company name here} Page 4HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Ground Covers (all nodes) HSG-A (sq-ft) HSG-B (sq-ft) HSG-C (sq-ft) HSG-D (sq-ft) Other (sq-ft) Total (sq-ft) Ground Cover Subcatchment Numbers 0 0 0 15,342 0 15,342 Woods, Good 1 S 0 0 0 15,342 0 15,342 TOTAL AREA Type II 24-hr 1 year Rainfall=2.14"predevelop Printed 12/28/2021Prepared by {enter your company name here} Page 5HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Time span=0.00-200.00 hrs, dt=0.05 hrs, 4001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=15,342 sf 0.00% Impervious Runoff Depth=0.53"Subcatchment 1S: (new Subcat) Flow Length=246' Tc=14.9 min CN=77 Runoff=0.22 cfs 672 cf Inflow=0.22 cfs 672 cfLink 2L: Primary=0.22 cfs 672 cf Total Runoff Area = 15,342 sf Runoff Volume = 672 cf Average Runoff Depth = 0.53" 100.00% Pervious = 15,342 sf 0.00% Impervious = 0 sf Type II 24-hr 1 year Rainfall=2.14"predevelop Printed 12/28/2021Prepared by {enter your company name here} Page 6HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: (new Subcat) Runoff = 0.22 cfs @ 12.09 hrs, Volume= 672 cf, Depth= 0.53" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 1 year Rainfall=2.14" Area (sf) CN Description 15,342 77 Woods, Good, HSG D 15,342 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 13.8 100 0.0825 0.12 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.2 23 0.1300 1.80 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.2 38 0.2950 2.72 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.4 40 0.1130 1.68 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.3 45 0.3222 2.84 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 14.9 246 Total Summary for Link 2L: Inflow Area = 15,342 sf, 0.00% Impervious, Inflow Depth = 0.53" for 1 year event Inflow = 0.22 cfs @ 12.09 hrs, Volume= 672 cf Primary = 0.22 cfs @ 12.09 hrs, Volume= 672 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 10 year Rainfall=3.52"predevelop Printed 12/28/2021Prepared by {enter your company name here} Page 7HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Time span=0.00-200.00 hrs, dt=0.05 hrs, 4001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=15,342 sf 0.00% Impervious Runoff Depth=1.45"Subcatchment 1S: (new Subcat) Flow Length=246' Tc=14.9 min CN=77 Runoff=0.65 cfs 1,848 cf Inflow=0.65 cfs 1,848 cfLink 2L: Primary=0.65 cfs 1,848 cf Total Runoff Area = 15,342 sf Runoff Volume = 1,848 cf Average Runoff Depth = 1.45" 100.00% Pervious = 15,342 sf 0.00% Impervious = 0 sf Type II 24-hr 10 year Rainfall=3.52"predevelop Printed 12/28/2021Prepared by {enter your company name here} Page 8HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: (new Subcat) Runoff = 0.65 cfs @ 12.08 hrs, Volume= 1,848 cf, Depth= 1.45" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 10 year Rainfall=3.52" Area (sf) CN Description 15,342 77 Woods, Good, HSG D 15,342 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 13.8 100 0.0825 0.12 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.2 23 0.1300 1.80 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.2 38 0.2950 2.72 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.4 40 0.1130 1.68 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.3 45 0.3222 2.84 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 14.9 246 Total Summary for Link 2L: Inflow Area = 15,342 sf, 0.00% Impervious, Inflow Depth = 1.45" for 10 year event Inflow = 0.65 cfs @ 12.08 hrs, Volume= 1,848 cf Primary = 0.65 cfs @ 12.08 hrs, Volume= 1,848 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 25 year Rainfall=4.95"predevelop Printed 12/28/2021Prepared by {enter your company name here} Page 9HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Time span=0.00-200.00 hrs, dt=0.05 hrs, 4001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=15,342 sf 0.00% Impervious Runoff Depth=2.58"Subcatchment 1S: (new Subcat) Flow Length=246' Tc=14.9 min CN=77 Runoff=1.17 cfs 3,300 cf Inflow=1.17 cfs 3,300 cfLink 2L: Primary=1.17 cfs 3,300 cf Total Runoff Area = 15,342 sf Runoff Volume = 3,300 cf Average Runoff Depth = 2.58" 100.00% Pervious = 15,342 sf 0.00% Impervious = 0 sf Type II 24-hr 25 year Rainfall=4.95"predevelop Printed 12/28/2021Prepared by {enter your company name here} Page 10HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: (new Subcat) Runoff = 1.17 cfs @ 12.07 hrs, Volume= 3,300 cf, Depth= 2.58" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 25 year Rainfall=4.95" Area (sf) CN Description 15,342 77 Woods, Good, HSG D 15,342 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 13.8 100 0.0825 0.12 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.2 23 0.1300 1.80 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.2 38 0.2950 2.72 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.4 40 0.1130 1.68 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.3 45 0.3222 2.84 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 14.9 246 Total Summary for Link 2L: Inflow Area = 15,342 sf, 0.00% Impervious, Inflow Depth = 2.58" for 25 year event Inflow = 1.17 cfs @ 12.07 hrs, Volume= 3,300 cf Primary = 1.17 cfs @ 12.07 hrs, Volume= 3,300 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Stormwater Management Narrative Bay Parkway. Town of Queensbury, New York 900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com Appendix C Post-development Stormwater Modeling Calculations 430420420410410400 390 380370360 370380390400 1" = 30'POSTDEVELOPMENTS-7PROPOSED SITE IMPROVEMENTS FOR 20 BURNT RIDGE ROAD TOWN OF QUEENSBURY JUNE 14, 2021 SLOTE RESIDENCE WARREN COUNTY, NEW YORK TAX MAP. No. 239.16-1-9900 Route 146 Clifton Park, New York 12065 edpllp.com(518) 371-7621 E N V I R O N M E N T A L D E S I G N P A R T N E R S H I P, L L P. S1 west roof S2 east roof S3 land R1 R2 SMA#1 SMA#2 OFF1 Routing Diagram for postdevelopment Prepared by {enter your company name here}, Printed 12/28/2021 HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Subcat Reach Pond Link postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 2HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (sq-ft) CN Description (subcatchment-numbers) 6,382 80 >75% Grass cover, Good, HSG D (S1, S2, S3) 703 98 Paved parking, HSG D (S3) 1,206 98 Unconnected roofs, HSG D (S1, S2) 7,092 77 Woods, Good, HSG D (S3) 15,383 81 TOTAL AREA postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 3HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (sq-ft) Soil Group Subcatchment Numbers 0 HSG A 0 HSG B 0 HSG C 15,383 HSG D S1, S2, S3 0 Other 15,383 TOTAL AREA postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 4HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Ground Covers (all nodes) HSG-A (sq-ft) HSG-B (sq-ft) HSG-C (sq-ft) HSG-D (sq-ft) Other (sq-ft) Total (sq-ft) Ground Cover Subcatchment Numbers 0 0 0 6,382 0 6,382 >75% Grass cover, Good 0 0 0 703 0 703 Paved parking 0 0 0 1,206 0 1,206 Unconnected roofs 0 0 0 7,092 0 7,092 Woods, Good 0 0 0 15,383 0 15,383 TOTAL AREA Type II 24-hr 1 year Rainfall=2.14"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 5HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Time span=0.00-200.00 hrs, dt=0.05 hrs, 4001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=831 sf 84.12% Impervious Runoff Depth=1.62"Subcatchment S1: west roof Tc=0.0 min CN=95 Runoff=0.06 cfs 112 cf Runoff Area=617 sf 82.17% Impervious Runoff Depth=1.62"Subcatchment S2: east roof Tc=0.0 min CN=95 Runoff=0.04 cfs 83 cf Runoff Area=13,935 sf 5.04% Impervious Runoff Depth=0.61"Subcatchment S3: land Flow Length=265' Tc=20.5 min CN=79 Runoff=0.19 cfs 704 cf Avg. Flow Depth=0.00' Max Vel=0.00 fps Inflow=0.00 cfs 0 cfReach R1: n=0.022 L=37.0' S=0.1622 '/' Capacity=461.56 cfs Outflow=0.00 cfs 0 cf Avg. Flow Depth=0.00' Max Vel=0.00 fps Inflow=0.00 cfs 0 cfReach R2: n=0.100 L=35.0' S=0.6571 '/' Capacity=490.02 cfs Outflow=0.00 cfs 0 cf Peak Elev=400.48' Storage=26 cf Inflow=0.06 cfs 112 cfPond SMA#1: Discarded=0.02 cfs 112 cf Primary=0.00 cfs 0 cf Outflow=0.02 cfs 112 cf Peak Elev=400.55' Storage=20 cf Inflow=0.04 cfs 83 cfPond SMA#2: Discarded=0.01 cfs 83 cf Primary=0.00 cfs 0 cf Outflow=0.01 cfs 83 cf Inflow=0.19 cfs 704 cfLink OFF1: Primary=0.19 cfs 704 cf Total Runoff Area = 15,383 sf Runoff Volume = 899 cf Average Runoff Depth = 0.70" 87.59% Pervious = 13,474 sf 12.41% Impervious = 1,909 sf Type II 24-hr 1 year Rainfall=2.14"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 6HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Summary for Subcatchment S1: west roof Runoff = 0.06 cfs @ 11.89 hrs, Volume= 112 cf, Depth= 1.62" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 1 year Rainfall=2.14" Area (sf) CN Description 699 98 Unconnected roofs, HSG D 132 80 >75% Grass cover, Good, HSG D 831 95 Weighted Average 132 15.88% Pervious Area 699 84.12% Impervious Area 699 100.00% Unconnected Summary for Subcatchment S2: east roof Runoff = 0.04 cfs @ 11.89 hrs, Volume= 83 cf, Depth= 1.62" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 1 year Rainfall=2.14" Area (sf) CN Description 507 98 Unconnected roofs, HSG D 110 80 >75% Grass cover, Good, HSG D 617 95 Weighted Average 110 17.83% Pervious Area 507 82.17% Impervious Area 507 100.00% Unconnected Summary for Subcatchment S3: land Runoff = 0.19 cfs @ 12.15 hrs, Volume= 704 cf, Depth= 0.61" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 1 year Rainfall=2.14" Area (sf) CN Description 703 98 Paved parking, HSG D 7,092 77 Woods, Good, HSG D 6,140 80 >75% Grass cover, Good, HSG D 13,935 79 Weighted Average 13,232 94.96% Pervious Area 703 5.04% Impervious Area Type II 24-hr 1 year Rainfall=2.14"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 7HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.8 54 0.0740 0.10 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 4.4 27 0.0370 0.10 Sheet Flow, Grass: Dense n= 0.240 P2= 2.51" 3.1 18 0.1110 0.10 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.2 31 0.1940 2.20 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 3.5 33 0.2730 0.16 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.1 27 0.0740 5.52 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.1 27 0.0740 4.08 Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps 0.3 48 0.2710 2.60 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 20.5 265 Total Summary for Reach R1: Inflow Area = 1,448 sf, 83.29% Impervious, Inflow Depth = 0.00" for 1 year event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Max. Velocity= 0.00 fps, Min. Travel Time= 0.0 min Avg. Velocity = 0.00 fps, Avg. Travel Time= 0.0 min Peak Storage= 0 cf @ 0.00 hrs Average Depth at Peak Storage= 0.00' Bank-Full Depth= 2.00' Flow Area= 16.0 sf, Capacity= 461.56 cfs 2.00' x 2.00' deep channel, n= 0.022 Earth, clean & straight Side Slope Z-value= 3.0 '/' Top Width= 14.00' Length= 37.0' Slope= 0.1622 '/' Inlet Invert= 404.00', Outlet Invert= 398.00' Type II 24-hr 1 year Rainfall=2.14"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 8HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Summary for Reach R2: Inflow Area = 1,448 sf, 83.29% Impervious, Inflow Depth = 0.00" for 1 year event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Max. Velocity= 0.00 fps, Min. Travel Time= 0.0 min Avg. Velocity = 0.00 fps, Avg. Travel Time= 0.0 min Peak Storage= 0 cf @ 0.00 hrs Average Depth at Peak Storage= 0.00' Bank-Full Depth= 2.00' Flow Area= 30.0 sf, Capacity= 490.02 cfs 15.00' x 2.00' deep channel, n= 0.100 Heavy timber, flow below branches Length= 35.0' Slope= 0.6571 '/' Inlet Invert= 398.00', Outlet Invert= 375.00' ‡ Summary for Pond SMA#1: Inflow Area = 831 sf, 84.12% Impervious, Inflow Depth = 1.62" for 1 year event Inflow = 0.06 cfs @ 11.89 hrs, Volume= 112 cf Outflow = 0.02 cfs @ 11.75 hrs, Volume= 112 cf, Atten= 74%, Lag= 0.0 min Discarded = 0.02 cfs @ 11.75 hrs, Volume= 112 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Peak Elev= 400.48' @ 12.00 hrs Surf.Area= 134 sf Storage= 26 cf Plug-Flow detention time= 8.8 min calculated for 112 cf (100% of inflow) Center-of-Mass det. time= 8.8 min ( 794.2 - 785.5 ) Volume Invert Avail.Storage Storage Description #1 400.00' 302 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Voids Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (%) (cubic-feet) (cubic-feet) (sq-ft) 400.00 134 68.0 0.0 0 0 134 403.00 134 68.0 40.0 161 161 338 404.50 134 68.0 20.0 40 201 440 405.25 134 68.0 100.0 101 302 491 Type II 24-hr 1 year Rainfall=2.14"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 9HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Device Routing Invert Outlet Devices #1 Discarded 400.00'5.000 in/hr Exfiltration over Surface area #2 Primary 405.00'5.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #3 Primary 404.75'8.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Discarded OutFlow Max=0.02 cfs @ 11.75 hrs HW=400.08' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=400.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) 3=Orifice/Grate ( Controls 0.00 cfs) Summary for Pond SMA#2: Inflow Area = 617 sf, 82.17% Impervious, Inflow Depth = 1.62" for 1 year event Inflow = 0.04 cfs @ 11.89 hrs, Volume= 83 cf Outflow = 0.01 cfs @ 11.70 hrs, Volume= 83 cf, Atten= 76%, Lag= 0.0 min Discarded = 0.01 cfs @ 11.70 hrs, Volume= 83 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Peak Elev= 400.55' @ 12.01 hrs Surf.Area= 91 sf Storage= 20 cf Plug-Flow detention time= 10.2 min calculated for 83 cf (100% of inflow) Center-of-Mass det. time= 10.2 min ( 795.6 - 785.5 ) Volume Invert Avail.Storage Storage Description #1 400.00' 205 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Voids Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (%) (cubic-feet) (cubic-feet) (sq-ft) 400.00 91 42.0 0.0 0 0 91 403.00 91 42.0 40.0 109 109 217 404.50 91 42.0 20.0 27 137 280 405.25 91 42.0 100.0 68 205 312 Device Routing Invert Outlet Devices #1 Discarded 400.00'5.000 in/hr Exfiltration over Surface area #2 Primary 405.00'5.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #3 Primary 404.75'8.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Type II 24-hr 1 year Rainfall=2.14"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 10HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.01 cfs @ 11.70 hrs HW=400.06' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=400.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) 3=Orifice/Grate ( Controls 0.00 cfs) Summary for Link OFF1: Inflow Area = 15,383 sf, 12.41% Impervious, Inflow Depth = 0.55" for 1 year event Inflow = 0.19 cfs @ 12.15 hrs, Volume= 704 cf Primary = 0.19 cfs @ 12.15 hrs, Volume= 704 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 10 year Rainfall=3.52"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 11HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Time span=0.00-200.00 hrs, dt=0.05 hrs, 4001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=831 sf 84.12% Impervious Runoff Depth=2.96"Subcatchment S1: west roof Tc=0.0 min CN=95 Runoff=0.10 cfs 205 cf Runoff Area=617 sf 82.17% Impervious Runoff Depth=2.96"Subcatchment S2: east roof Tc=0.0 min CN=95 Runoff=0.08 cfs 152 cf Runoff Area=13,935 sf 5.04% Impervious Runoff Depth=1.58"Subcatchment S3: land Flow Length=265' Tc=20.5 min CN=79 Runoff=0.55 cfs 1,837 cf Avg. Flow Depth=0.00' Max Vel=0.00 fps Inflow=0.00 cfs 0 cfReach R1: n=0.022 L=37.0' S=0.1622 '/' Capacity=461.56 cfs Outflow=0.00 cfs 0 cf Avg. Flow Depth=0.00' Max Vel=0.00 fps Inflow=0.00 cfs 0 cfReach R2: n=0.100 L=35.0' S=0.6571 '/' Capacity=490.02 cfs Outflow=0.00 cfs 0 cf Peak Elev=401.13' Storage=61 cf Inflow=0.10 cfs 205 cfPond SMA#1: Discarded=0.02 cfs 205 cf Primary=0.00 cfs 0 cf Outflow=0.02 cfs 205 cf Peak Elev=401.28' Storage=47 cf Inflow=0.08 cfs 152 cfPond SMA#2: Discarded=0.01 cfs 152 cf Primary=0.00 cfs 0 cf Outflow=0.01 cfs 152 cf Inflow=0.55 cfs 1,837 cfLink OFF1: Primary=0.55 cfs 1,837 cf Total Runoff Area = 15,383 sf Runoff Volume = 2,194 cf Average Runoff Depth = 1.71" 87.59% Pervious = 13,474 sf 12.41% Impervious = 1,909 sf Type II 24-hr 10 year Rainfall=3.52"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 12HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Summary for Subcatchment S1: west roof Runoff = 0.10 cfs @ 11.89 hrs, Volume= 205 cf, Depth= 2.96" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 10 year Rainfall=3.52" Area (sf) CN Description 699 98 Unconnected roofs, HSG D 132 80 >75% Grass cover, Good, HSG D 831 95 Weighted Average 132 15.88% Pervious Area 699 84.12% Impervious Area 699 100.00% Unconnected Summary for Subcatchment S2: east roof Runoff = 0.08 cfs @ 11.89 hrs, Volume= 152 cf, Depth= 2.96" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 10 year Rainfall=3.52" Area (sf) CN Description 507 98 Unconnected roofs, HSG D 110 80 >75% Grass cover, Good, HSG D 617 95 Weighted Average 110 17.83% Pervious Area 507 82.17% Impervious Area 507 100.00% Unconnected Summary for Subcatchment S3: land Runoff = 0.55 cfs @ 12.14 hrs, Volume= 1,837 cf, Depth= 1.58" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 10 year Rainfall=3.52" Area (sf) CN Description 703 98 Paved parking, HSG D 7,092 77 Woods, Good, HSG D 6,140 80 >75% Grass cover, Good, HSG D 13,935 79 Weighted Average 13,232 94.96% Pervious Area 703 5.04% Impervious Area Type II 24-hr 10 year Rainfall=3.52"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 13HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.8 54 0.0740 0.10 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 4.4 27 0.0370 0.10 Sheet Flow, Grass: Dense n= 0.240 P2= 2.51" 3.1 18 0.1110 0.10 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.2 31 0.1940 2.20 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 3.5 33 0.2730 0.16 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.1 27 0.0740 5.52 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.1 27 0.0740 4.08 Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps 0.3 48 0.2710 2.60 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 20.5 265 Total Summary for Reach R1: Inflow Area = 1,448 sf, 83.29% Impervious, Inflow Depth = 0.00" for 10 year event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Max. Velocity= 0.00 fps, Min. Travel Time= 0.0 min Avg. Velocity = 0.00 fps, Avg. Travel Time= 0.0 min Peak Storage= 0 cf @ 0.00 hrs Average Depth at Peak Storage= 0.00' Bank-Full Depth= 2.00' Flow Area= 16.0 sf, Capacity= 461.56 cfs 2.00' x 2.00' deep channel, n= 0.022 Earth, clean & straight Side Slope Z-value= 3.0 '/' Top Width= 14.00' Length= 37.0' Slope= 0.1622 '/' Inlet Invert= 404.00', Outlet Invert= 398.00' Type II 24-hr 10 year Rainfall=3.52"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 14HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Summary for Reach R2: Inflow Area = 1,448 sf, 83.29% Impervious, Inflow Depth = 0.00" for 10 year event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Max. Velocity= 0.00 fps, Min. Travel Time= 0.0 min Avg. Velocity = 0.00 fps, Avg. Travel Time= 0.0 min Peak Storage= 0 cf @ 0.00 hrs Average Depth at Peak Storage= 0.00' Bank-Full Depth= 2.00' Flow Area= 30.0 sf, Capacity= 490.02 cfs 15.00' x 2.00' deep channel, n= 0.100 Heavy timber, flow below branches Length= 35.0' Slope= 0.6571 '/' Inlet Invert= 398.00', Outlet Invert= 375.00' ‡ Summary for Pond SMA#1: Inflow Area = 831 sf, 84.12% Impervious, Inflow Depth = 2.96" for 10 year event Inflow = 0.10 cfs @ 11.89 hrs, Volume= 205 cf Outflow = 0.02 cfs @ 11.65 hrs, Volume= 205 cf, Atten= 85%, Lag= 0.0 min Discarded = 0.02 cfs @ 11.65 hrs, Volume= 205 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Peak Elev= 401.13' @ 12.03 hrs Surf.Area= 134 sf Storage= 61 cf Plug-Flow detention time= 22.0 min calculated for 205 cf (100% of inflow) Center-of-Mass det. time= 22.0 min ( 791.0 - 769.1 ) Volume Invert Avail.Storage Storage Description #1 400.00' 302 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Voids Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (%) (cubic-feet) (cubic-feet) (sq-ft) 400.00 134 68.0 0.0 0 0 134 403.00 134 68.0 40.0 161 161 338 404.50 134 68.0 20.0 40 201 440 405.25 134 68.0 100.0 101 302 491 Type II 24-hr 10 year Rainfall=3.52"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 15HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Device Routing Invert Outlet Devices #1 Discarded 400.00'5.000 in/hr Exfiltration over Surface area #2 Primary 405.00'5.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #3 Primary 404.75'8.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Discarded OutFlow Max=0.02 cfs @ 11.65 hrs HW=400.08' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=400.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) 3=Orifice/Grate ( Controls 0.00 cfs) Summary for Pond SMA#2: Inflow Area = 617 sf, 82.17% Impervious, Inflow Depth = 2.96" for 10 year event Inflow = 0.08 cfs @ 11.89 hrs, Volume= 152 cf Outflow = 0.01 cfs @ 11.60 hrs, Volume= 152 cf, Atten= 86%, Lag= 0.0 min Discarded = 0.01 cfs @ 11.60 hrs, Volume= 152 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Peak Elev= 401.28' @ 12.05 hrs Surf.Area= 91 sf Storage= 47 cf Plug-Flow detention time= 25.4 min calculated for 152 cf (100% of inflow) Center-of-Mass det. time= 25.4 min ( 794.5 - 769.1 ) Volume Invert Avail.Storage Storage Description #1 400.00' 205 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Voids Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (%) (cubic-feet) (cubic-feet) (sq-ft) 400.00 91 42.0 0.0 0 0 91 403.00 91 42.0 40.0 109 109 217 404.50 91 42.0 20.0 27 137 280 405.25 91 42.0 100.0 68 205 312 Device Routing Invert Outlet Devices #1 Discarded 400.00'5.000 in/hr Exfiltration over Surface area #2 Primary 405.00'5.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #3 Primary 404.75'8.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Type II 24-hr 10 year Rainfall=3.52"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 16HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.01 cfs @ 11.60 hrs HW=400.06' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=400.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) 3=Orifice/Grate ( Controls 0.00 cfs) Summary for Link OFF1: Inflow Area = 15,383 sf, 12.41% Impervious, Inflow Depth = 1.43" for 10 year event Inflow = 0.55 cfs @ 12.14 hrs, Volume= 1,837 cf Primary = 0.55 cfs @ 12.14 hrs, Volume= 1,837 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 25 year Rainfall=4.95"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 17HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Time span=0.00-200.00 hrs, dt=0.05 hrs, 4001 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=831 sf 84.12% Impervious Runoff Depth=4.37"Subcatchment S1: west roof Tc=0.0 min CN=95 Runoff=0.15 cfs 303 cf Runoff Area=617 sf 82.17% Impervious Runoff Depth=4.37"Subcatchment S2: east roof Tc=0.0 min CN=95 Runoff=0.11 cfs 225 cf Runoff Area=13,935 sf 5.04% Impervious Runoff Depth=2.76"Subcatchment S3: land Flow Length=265' Tc=20.5 min CN=79 Runoff=0.96 cfs 3,203 cf Avg. Flow Depth=0.00' Max Vel=0.00 fps Inflow=0.00 cfs 0 cfReach R1: n=0.022 L=37.0' S=0.1622 '/' Capacity=461.56 cfs Outflow=0.00 cfs 0 cf Avg. Flow Depth=0.00' Max Vel=0.00 fps Inflow=0.00 cfs 0 cfReach R2: n=0.100 L=35.0' S=0.6571 '/' Capacity=490.02 cfs Outflow=0.00 cfs 0 cf Peak Elev=401.87' Storage=100 cf Inflow=0.15 cfs 303 cfPond SMA#1: Discarded=0.02 cfs 303 cf Primary=0.00 cfs 0 cf Outflow=0.02 cfs 303 cf Peak Elev=402.11' Storage=77 cf Inflow=0.11 cfs 225 cfPond SMA#2: Discarded=0.01 cfs 225 cf Primary=0.00 cfs 0 cf Outflow=0.01 cfs 225 cf Inflow=0.96 cfs 3,203 cfLink OFF1: Primary=0.96 cfs 3,203 cf Total Runoff Area = 15,383 sf Runoff Volume = 3,731 cf Average Runoff Depth = 2.91" 87.59% Pervious = 13,474 sf 12.41% Impervious = 1,909 sf Type II 24-hr 25 year Rainfall=4.95"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 18HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Summary for Subcatchment S1: west roof Runoff = 0.15 cfs @ 11.89 hrs, Volume= 303 cf, Depth= 4.37" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 25 year Rainfall=4.95" Area (sf) CN Description 699 98 Unconnected roofs, HSG D 132 80 >75% Grass cover, Good, HSG D 831 95 Weighted Average 132 15.88% Pervious Area 699 84.12% Impervious Area 699 100.00% Unconnected Summary for Subcatchment S2: east roof Runoff = 0.11 cfs @ 11.89 hrs, Volume= 225 cf, Depth= 4.37" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 25 year Rainfall=4.95" Area (sf) CN Description 507 98 Unconnected roofs, HSG D 110 80 >75% Grass cover, Good, HSG D 617 95 Weighted Average 110 17.83% Pervious Area 507 82.17% Impervious Area 507 100.00% Unconnected Summary for Subcatchment S3: land Runoff = 0.96 cfs @ 12.13 hrs, Volume= 3,203 cf, Depth= 2.76" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Type II 24-hr 25 year Rainfall=4.95" Area (sf) CN Description 703 98 Paved parking, HSG D 7,092 77 Woods, Good, HSG D 6,140 80 >75% Grass cover, Good, HSG D 13,935 79 Weighted Average 13,232 94.96% Pervious Area 703 5.04% Impervious Area Type II 24-hr 25 year Rainfall=4.95"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 19HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 8.8 54 0.0740 0.10 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 4.4 27 0.0370 0.10 Sheet Flow, Grass: Dense n= 0.240 P2= 2.51" 3.1 18 0.1110 0.10 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.2 31 0.1940 2.20 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 3.5 33 0.2730 0.16 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.1 27 0.0740 5.52 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.1 27 0.0740 4.08 Shallow Concentrated Flow, Grassed Waterway Kv= 15.0 fps 0.3 48 0.2710 2.60 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 20.5 265 Total Summary for Reach R1: Inflow Area = 1,448 sf, 83.29% Impervious, Inflow Depth = 0.00" for 25 year event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Max. Velocity= 0.00 fps, Min. Travel Time= 0.0 min Avg. Velocity = 0.00 fps, Avg. Travel Time= 0.0 min Peak Storage= 0 cf @ 0.00 hrs Average Depth at Peak Storage= 0.00' Bank-Full Depth= 2.00' Flow Area= 16.0 sf, Capacity= 461.56 cfs 2.00' x 2.00' deep channel, n= 0.022 Earth, clean & straight Side Slope Z-value= 3.0 '/' Top Width= 14.00' Length= 37.0' Slope= 0.1622 '/' Inlet Invert= 404.00', Outlet Invert= 398.00' Type II 24-hr 25 year Rainfall=4.95"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 20HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Summary for Reach R2: Inflow Area = 1,448 sf, 83.29% Impervious, Inflow Depth = 0.00" for 25 year event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Outflow = 0.00 cfs @ 0.00 hrs, Volume= 0 cf, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind+Trans method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Max. Velocity= 0.00 fps, Min. Travel Time= 0.0 min Avg. Velocity = 0.00 fps, Avg. Travel Time= 0.0 min Peak Storage= 0 cf @ 0.00 hrs Average Depth at Peak Storage= 0.00' Bank-Full Depth= 2.00' Flow Area= 30.0 sf, Capacity= 490.02 cfs 15.00' x 2.00' deep channel, n= 0.100 Heavy timber, flow below branches Length= 35.0' Slope= 0.6571 '/' Inlet Invert= 398.00', Outlet Invert= 375.00' ‡ Summary for Pond SMA#1: Inflow Area = 831 sf, 84.12% Impervious, Inflow Depth = 4.37" for 25 year event Inflow = 0.15 cfs @ 11.89 hrs, Volume= 303 cf Outflow = 0.02 cfs @ 11.60 hrs, Volume= 303 cf, Atten= 89%, Lag= 0.0 min Discarded = 0.02 cfs @ 11.60 hrs, Volume= 303 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Peak Elev= 401.87' @ 12.15 hrs Surf.Area= 134 sf Storage= 100 cf Plug-Flow detention time= 39.1 min calculated for 303 cf (100% of inflow) Center-of-Mass det. time= 39.1 min ( 798.4 - 759.3 ) Volume Invert Avail.Storage Storage Description #1 400.00' 302 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Voids Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (%) (cubic-feet) (cubic-feet) (sq-ft) 400.00 134 68.0 0.0 0 0 134 403.00 134 68.0 40.0 161 161 338 404.50 134 68.0 20.0 40 201 440 405.25 134 68.0 100.0 101 302 491 Type II 24-hr 25 year Rainfall=4.95"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 21HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Device Routing Invert Outlet Devices #1 Discarded 400.00'5.000 in/hr Exfiltration over Surface area #2 Primary 405.00'5.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #3 Primary 404.75'8.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Discarded OutFlow Max=0.02 cfs @ 11.60 hrs HW=400.09' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.02 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=400.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) 3=Orifice/Grate ( Controls 0.00 cfs) Summary for Pond SMA#2: Inflow Area = 617 sf, 82.17% Impervious, Inflow Depth = 4.37" for 25 year event Inflow = 0.11 cfs @ 11.89 hrs, Volume= 225 cf Outflow = 0.01 cfs @ 11.55 hrs, Volume= 225 cf, Atten= 90%, Lag= 0.0 min Discarded = 0.01 cfs @ 11.55 hrs, Volume= 225 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs Peak Elev= 402.11' @ 12.22 hrs Surf.Area= 91 sf Storage= 77 cf Plug-Flow detention time= 44.9 min calculated for 225 cf (100% of inflow) Center-of-Mass det. time= 44.9 min ( 804.2 - 759.3 ) Volume Invert Avail.Storage Storage Description #1 400.00' 205 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Voids Inc.Store Cum.Store Wet.Area (feet) (sq-ft) (feet) (%) (cubic-feet) (cubic-feet) (sq-ft) 400.00 91 42.0 0.0 0 0 91 403.00 91 42.0 40.0 109 109 217 404.50 91 42.0 20.0 27 137 280 405.25 91 42.0 100.0 68 205 312 Device Routing Invert Outlet Devices #1 Discarded 400.00'5.000 in/hr Exfiltration over Surface area #2 Primary 405.00'5.0' long x 1.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 #3 Primary 404.75'8.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Type II 24-hr 25 year Rainfall=4.95"postdevelopment Printed 12/28/2021Prepared by {enter your company name here} Page 22HydroCAD® 10.00-20 s/n 11387 © 2017 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.01 cfs @ 11.55 hrs HW=400.05' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.01 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=400.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) 3=Orifice/Grate ( Controls 0.00 cfs) Summary for Link OFF1: Inflow Area = 15,383 sf, 12.41% Impervious, Inflow Depth = 2.50" for 25 year event Inflow = 0.96 cfs @ 12.13 hrs, Volume= 3,203 cf Primary = 0.96 cfs @ 12.13 hrs, Volume= 3,203 cf, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-200.00 hrs, dt= 0.05 hrs