Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Stormwater Report
900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com STORMWATER MANAGEMENT NARRATIVE DRIVEWAY ACCESS TO GRIFFEY RESIDENCE 26 TALL TIMBERS ROAD TOWN OF QUEENSBURY, NY Prepared by: Environmental Design Partnership Clifton Park, NY 12065 AUGUST 2022 Stormwater Management Narrative Driveway Access - Griffey 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 Griffey’s are proposing to construct a new driveway access to their existing dwelling located at 26 Tall Timbers Road in the Town of Lake George NY. The proposed driveway will extend from Old Assembly point road to their existing driveway located at the end of Tall Timbers Road. The proposed development will result in approximately 16,650 sf of soil disturbance (13,740 sf excluding the stormwater management areas) and the addition of approximately 5,740 sf of impervious area. With a total disturbance of less than 15,000 sf, excluding the stormwater management areas, the proposed project qualifies for a minor stormwater permit. However, due to anticipate future projects on the site the stormwater system was designed to meet the major stormwater permit standards as by providing for a reduction in the stormwater runoff rates and volumes in accordance with the Town of Queensbury Stormwater Management Regulations. The proposed stormwater management system will include 3 shallow infiltration basins. This narrative presents a review of the design concepts and parameters of the stormwater management system for the proposed development. 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. The 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 are of proposed development consists mainly of woods with some open grass areas. The topography of the site in the area of the proposed development is relatively steep with the majority of the slopes ranging from 10% to 25% with the site generally draining toward either Lake George, Old Assembly Point Road or the neighboring property to the north. 2.1 Soil and Groundwater Conditions The USDA Natural Resources Conservation Service Soil Survey identifies the two primary soil groups within the area of the proposed development to be BeC and BeE, which are Bice- Woodstock very boulder fine sandy loam. Both of these soils are well draining and classified as HSG “B”. Soil test probes were performed throughout the site in June 2022 and resulted in an existing topsoil depth of 8” – 12” over the top of existing bedrock. Stormwater Management Narrative Driveway Access - Griffey 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 PRE-EXISTING STORMWATER ANALYSIS A hydraulic model of the pre-existing site was prepared using the Hydrocad program. Three subcatchments were 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 results for the existing condition model are summarized in the table below and have been included in Appendix A. Table 1: Pre-Existing Runoff Rates Storm Event Total Runoff Rate 10 Year (3.52”) 0.56 cfs 25 Year (4.27”) 1.35 cfs 4.0 POST DEVELOPMENT STORMWATER ANALYSIS Site improvements to the property will consist of a new private driveway extending from Old Assembly Point Road to the existing driveway at the end of Tall Timbers Road. Stormwater management practices have been designed to provide filtration, infiltration capacity and attenuation of stormwater runoff from the proposed impervious surfaces on the site. The proposed stormwater management system shall consist of three (3) shallow infiltration basins. 4.1 Shallow Infiltration Bains Stormwater Management Areas #1, 2 and have been designed to treat and infiltrate runoff from portions of the proposed driveway. The shallow infiltration basins will allow for the treatment, attenuation and infiltration of the contributing stormwater runoff. Stormwater runoff will be conveyed to the stormwater management areas via a combination of grassed swales and a stone trench. The proposed grassed swale will include check dams to slow down the flows and to allow for pretreatment prior to entering the stormwater basin. The proposed stormwater management areas will contain reinforced overflow weirs in order to convey any overflows toward the existing drainage corridors. 4.2 Town of Queensbury Stormwater Regulations The proposed project will consist of less than 15,000 square feet of disturbance (excluding stormwater management areas) and therefore, according the Chapter 147 of the town code, is considered a minor project. However, due to existing site conditions and in anticipation of future Stormwater Management Narrative Driveway Access - Griffey Town of Queensbury, New York 900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com site modifications the proposed stormwater management has been designed in accordance with the Major Project stormwater requirements in the Queensbury Town Code. The major stormwater requirements mandate that the volume of runoff for a ten-year storm must be maintained after development and that the peak rate of runoff must not be increased for the 25- year storm. The following tables summarize the stormwater modeling results. Table 8: 10-Year (3.52 inch) Design Storm Runoff Volume Design Point Predevelopment Runoff Volume (ac-ft) Post-Development Runoff Volume (ac-ft) 1 0.013 0.002 2 0.031 0.005 3 0.013 0.013 Table 9: 25-Year (4.27 inch) Design Storm Runoff Rate Design Point Predevelopment Runoff Rate (cfs) Post-Development Runoff Rate (cfs) 1 0.32 0.23 2 0.74 0.74 3 0.29 0.26 5.0 SUMMARY Development of the proposed property will change the stormwater drainage characteristics of the site; impervious area will be added and the site will be re-graded to support the proposed 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: Brandon M. Ferguson, P.E. Stormwater Management Narrative Driveway Access - Griffey 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 Driveway Access - Griffey 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 6/6/2022 Page 1 of 34811750481177048117904811810481183048118504811870481189048117504811770481179048118104811830481185048118704811890608840608860608880608900608920608940608960608980609000609020609040609060609080 608840 608860 608880 608900 608920 608940 608960 608980 609000 609020 609040 609060 609080 43° 27' 7'' N 73° 39' 17'' W43° 27' 7'' N73° 39' 6'' W43° 27' 2'' N 73° 39' 17'' W43° 27' 2'' N 73° 39' 6'' 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: 1:1,120 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI BeC Bice-Woodstock very bouldery fine sandy loams, sloping 1.1 39.3% BeE Bice-Woodstock very bouldery fine sandy loams, steep 1.7 60.4% W Water 0.0 0.3% Totals for Area of Interest 2.8 100.0% Soil Map—Warren County, New York Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/6/2022 Page 3 of 3 Stormwater Management Narrative Driveway Access - Griffey 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 PROPOSED STORMWATER DESIGN 26 TALL TIMBERS ROAD TOWN OF QUEENSBURY AUGUST 11, 2022 GRIFFEY RESIDENCE 1"=50'PREDEVELOPMENTSTORMWATERWARREN COUNTY, NEW YORK2 900 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. DRIVEWAY ACCESS 1S 2S 3S 1 DRIVEWAY/LAKE 2 NORTH 3 ROAD Routing Diagram for PRE-EXISTING Prepared by {enter your company name here}, Printed 8/30/2022 HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Subcat Reach Pond Link PRE-EXISTING Printed 8/30/2022Prepared by {enter your company name here} Page 2HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Rainfall Events Listing (selected events) Event# Event Name Storm Type Curve Mode Duration (hours) B/B Depth (inches) AMC 1 10 yr Type II 24-hr Default 24.00 1 3.52 2 2 25 yr Type II 24-hr Default 24.00 1 4.27 2 PRE-EXISTING Printed 8/30/2022Prepared by {enter your company name here} Page 3HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CN Description (subcatchment-numbers) 0.018 98 OFFSITE DRIVE (2S) 1.824 55 Woods, Good, HSG B (1S, 2S, 3S) 1.842 55 TOTAL AREA PRE-EXISTING Printed 8/30/2022Prepared by {enter your company name here} Page 4HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers 0.000 HSG A 1.824 HSG B 1S, 2S, 3S 0.000 HSG C 0.000 HSG D 0.018 Other 2S 1.842 TOTAL AREA PRE-EXISTING Printed 8/30/2022Prepared by {enter your company name here} Page 5HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Ground Covers (all nodes) HSG-A (acres) HSG-B (acres) HSG-C (acres) HSG-D (acres) Other (acres) Total (acres) Ground Cover Subcatchment Numbers 0.000 0.000 0.000 0.000 0.018 0.018 OFFSITE DRIVE 2S 0.000 1.824 0.000 0.000 0.000 1.824 Woods, Good 1S, 2S, 3S 0.000 1.824 0.000 0.000 0.018 1.842 TOTAL AREA Type II 24-hr 10 yr Rainfall=3.52"PRE-EXISTING Printed 8/30/2022Prepared by {enter your company name here} Page 6HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Time span=0.00-100.00 hrs, dt=0.05 hrs, 2001 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=18,990 sf 0.00% Impervious Runoff Depth=0.35"Subcatchment 1S: Flow Length=280' Tc=10.6 min CN=55 Runoff=0.13 cfs 0.013 af Runoff Area=42,390 sf 1.84% Impervious Runoff Depth=0.39"Subcatchment 2S: Flow Length=260' Tc=12.1 min CN=56 Runoff=0.31 cfs 0.031 af Runoff Area=18,850 sf 0.00% Impervious Runoff Depth=0.35"Subcatchment 3S: Flow Length=210' Tc=12.4 min CN=55 Runoff=0.12 cfs 0.013 af Inflow=0.13 cfs 0.013 afLink 1: DRIVEWAY/LAKE Primary=0.13 cfs 0.013 af Inflow=0.31 cfs 0.031 afLink 2: NORTH Primary=0.31 cfs 0.031 af Inflow=0.12 cfs 0.013 afLink 3: ROAD Primary=0.12 cfs 0.013 af Total Runoff Area = 1.842 ac Runoff Volume = 0.057 af Average Runoff Depth = 0.37" 99.03% Pervious = 1.824 ac 0.97% Impervious = 0.018 ac Type II 24-hr 10 yr Rainfall=3.52"PRE-EXISTING Printed 8/30/2022Prepared by {enter your company name here} Page 7HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: Runoff = 0.13 cfs @ 12.07 hrs, Volume= 0.013 af, Depth= 0.35" Routed to Link 1 : DRIVEWAY/LAKE Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=3.52" Area (sf) CN Description 18,990 55 Woods, Good, HSG B 18,990 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.3 100 0.2200 0.18 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 1.3 180 0.2300 2.40 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 10.6 280 Total Summary for Subcatchment 2S: Runoff = 0.31 cfs @ 12.09 hrs, Volume= 0.031 af, Depth= 0.39" Routed to Link 2 : NORTH Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=3.52" Area (sf) CN Description * 780 98 OFFSITE DRIVE 41,610 55 Woods, Good, HSG B 42,390 56 Weighted Average 41,610 98.16% Pervious Area 780 1.84% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.8 100 0.1500 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 1.3 160 0.1800 2.12 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 12.1 260 Total Summary for Subcatchment 3S: Runoff = 0.12 cfs @ 12.10 hrs, Volume= 0.013 af, Depth= 0.35" Routed to Link 3 : ROAD Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=3.52" Type II 24-hr 10 yr Rainfall=3.52"PRE-EXISTING Printed 8/30/2022Prepared by {enter your company name here} Page 8HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Area (sf) CN Description 18,850 55 Woods, Good, HSG B 18,850 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.5 100 0.1300 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.9 110 0.1500 1.94 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 12.4 210 Total Summary for Link 1: DRIVEWAY/LAKE Inflow Area = 0.436 ac, 0.00% Impervious, Inflow Depth = 0.35" for 10 yr event Inflow = 0.13 cfs @ 12.07 hrs, Volume= 0.013 af Primary = 0.13 cfs @ 12.07 hrs, Volume= 0.013 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Summary for Link 2: NORTH Inflow Area = 0.973 ac, 1.84% Impervious, Inflow Depth = 0.39" for 10 yr event Inflow = 0.31 cfs @ 12.09 hrs, Volume= 0.031 af Primary = 0.31 cfs @ 12.09 hrs, Volume= 0.031 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Summary for Link 3: ROAD Inflow Area = 0.433 ac, 0.00% Impervious, Inflow Depth = 0.35" for 10 yr event Inflow = 0.12 cfs @ 12.10 hrs, Volume= 0.013 af Primary = 0.12 cfs @ 12.10 hrs, Volume= 0.013 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27"PRE-EXISTING Printed 8/30/2022Prepared by {enter your company name here} Page 9HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Time span=0.00-100.00 hrs, dt=0.05 hrs, 2001 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=18,990 sf 0.00% Impervious Runoff Depth=0.64"Subcatchment 1S: Flow Length=280' Tc=10.6 min CN=55 Runoff=0.32 cfs 0.023 af Runoff Area=42,390 sf 1.84% Impervious Runoff Depth=0.69"Subcatchment 2S: Flow Length=260' Tc=12.1 min CN=56 Runoff=0.74 cfs 0.056 af Runoff Area=18,850 sf 0.00% Impervious Runoff Depth=0.64"Subcatchment 3S: Flow Length=210' Tc=12.4 min CN=55 Runoff=0.29 cfs 0.023 af Inflow=0.32 cfs 0.023 afLink 1: DRIVEWAY/LAKE Primary=0.32 cfs 0.023 af Inflow=0.74 cfs 0.056 afLink 2: NORTH Primary=0.74 cfs 0.056 af Inflow=0.29 cfs 0.023 afLink 3: ROAD Primary=0.29 cfs 0.023 af Total Runoff Area = 1.842 ac Runoff Volume = 0.102 af Average Runoff Depth = 0.67" 99.03% Pervious = 1.824 ac 0.97% Impervious = 0.018 ac Type II 24-hr 25 yr Rainfall=4.27"PRE-EXISTING Printed 8/30/2022Prepared by {enter your company name here} Page 10HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: Runoff = 0.32 cfs @ 12.05 hrs, Volume= 0.023 af, Depth= 0.64" Routed to Link 1 : DRIVEWAY/LAKE Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27" Area (sf) CN Description 18,990 55 Woods, Good, HSG B 18,990 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.3 100 0.2200 0.18 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 1.3 180 0.2300 2.40 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 10.6 280 Total Summary for Subcatchment 2S: Runoff = 0.74 cfs @ 12.07 hrs, Volume= 0.056 af, Depth= 0.69" Routed to Link 2 : NORTH Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27" Area (sf) CN Description * 780 98 OFFSITE DRIVE 41,610 55 Woods, Good, HSG B 42,390 56 Weighted Average 41,610 98.16% Pervious Area 780 1.84% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.8 100 0.1500 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 1.3 160 0.1800 2.12 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 12.1 260 Total Summary for Subcatchment 3S: Runoff = 0.29 cfs @ 12.07 hrs, Volume= 0.023 af, Depth= 0.64" Routed to Link 3 : ROAD Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27" Type II 24-hr 25 yr Rainfall=4.27"PRE-EXISTING Printed 8/30/2022Prepared by {enter your company name here} Page 11HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Area (sf) CN Description 18,850 55 Woods, Good, HSG B 18,850 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.5 100 0.1300 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.9 110 0.1500 1.94 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 12.4 210 Total Summary for Link 1: DRIVEWAY/LAKE Inflow Area = 0.436 ac, 0.00% Impervious, Inflow Depth = 0.64" for 25 yr event Inflow = 0.32 cfs @ 12.05 hrs, Volume= 0.023 af Primary = 0.32 cfs @ 12.05 hrs, Volume= 0.023 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Summary for Link 2: NORTH Inflow Area = 0.973 ac, 1.84% Impervious, Inflow Depth = 0.69" for 25 yr event Inflow = 0.74 cfs @ 12.07 hrs, Volume= 0.056 af Primary = 0.74 cfs @ 12.07 hrs, Volume= 0.056 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Summary for Link 3: ROAD Inflow Area = 0.433 ac, 0.00% Impervious, Inflow Depth = 0.64" for 25 yr event Inflow = 0.29 cfs @ 12.07 hrs, Volume= 0.023 af Primary = 0.29 cfs @ 12.07 hrs, Volume= 0.023 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Stormwater Management Narrative Driveway Access - Griffey 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 PROPOSED STORMWATER DESIGN 26 TALL TIMBERS ROAD TOWN OF QUEENSBURY AUGUST 11, 2022 GRIFFEY RESIDENCE 1"=50'POSTDEVELOPMENTSTORMWATERWARREN COUNTY, NEW YORK3 900 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. DRIVEWAY ACCESS 1A 1B 2A 2B 3A 3B 3C P1 SMA#1 P2 SMA#2 P3 SMA#3 1 DRIVEWAY/LAKE 2 NORTH 3 ROAD Routing Diagram for POST-DEVELOPMENT Prepared by {enter your company name here}, Printed 8/30/2022 HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Subcat Reach Pond Link POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 2HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Rainfall Events Listing (selected events) Event# Event Name Storm Type Curve Mode Duration (hours) B/B Depth (inches) AMC 1 10 yr Type II 24-hr Default 24.00 1 3.52 2 2 25 yr Type II 24-hr Default 24.00 1 4.27 2 POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 3HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CN Description (subcatchment-numbers) 0.409 61 >75% Grass cover, Good, HSG B (1B, 2A, 2B, 3A, 3C) 0.118 98 DRIVE PAVED (1A, 1B, 2B, 3C) 0.018 98 OFFSITE DRIVE (2B) 0.041 98 PAVED COURT (1B) 1.257 55 Woods, Good, HSG B (1A, 1B, 2A, 2B, 3A, 3B, 3C) 1.843 60 TOTAL AREA POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 4HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers 0.000 HSG A 1.666 HSG B 1A, 1B, 2A, 2B, 3A, 3B, 3C 0.000 HSG C 0.000 HSG D 0.177 Other 1A, 1B, 2B, 3C 1.843 TOTAL AREA POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 5HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Ground Covers (all nodes) HSG-A (acres) HSG-B (acres) HSG-C (acres) HSG-D (acres) Other (acres) Total (acres) Ground Cover Subcatchment Numbers 0.000 0.409 0.000 0.000 0.000 0.409 >75% Grass cover, Good 1B, 2A, 2B, 3A, 3C 0.000 0.000 0.000 0.000 0.118 0.118 DRIVE PAVED 1A, 1B, 2B, 3C 0.000 0.000 0.000 0.000 0.018 0.018 OFFSITE DRIVE 2B 0.000 0.000 0.000 0.000 0.041 0.041 PAVED COURT 1B 0.000 1.257 0.000 0.000 0.000 1.257 Woods, Good 1A, 1B, 2A, 2B, 3A, 3B, 3C 0.000 1.666 0.000 0.000 0.177 1.843 TOTAL AREA Type II 24-hr 10 yr Rainfall=3.52"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 6HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Time span=0.00-100.00 hrs, dt=0.05 hrs, 2001 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=810 sf 45.68% Impervious Runoff Depth=1.32"Subcatchment 1A: Flow Length=30' Slope=0.1500 '/' Tc=0.2 min CN=75 Runoff=0.05 cfs 0.002 af Runoff Area=21,030 sf 16.36% Impervious Runoff Depth=0.72"Subcatchment 1B: Flow Length=295' Tc=10.2 min CN=64 Runoff=0.46 cfs 0.029 af Runoff Area=3,290 sf 0.00% Impervious Runoff Depth=0.39"Subcatchment 2A: Flow Length=50' Slope=0.2000 '/' Tc=5.5 min CN=56 Runoff=0.04 cfs 0.002 af Runoff Area=26,340 sf 11.62% Impervious Runoff Depth=0.58"Subcatchment 2B: Flow Length=382' Tc=12.8 min CN=61 Runoff=0.38 cfs 0.029 af Runoff Area=1,500 sf 0.00% Impervious Runoff Depth=0.50"Subcatchment 3A: Flow Length=50' Tc=2.3 min CN=59 Runoff=0.03 cfs 0.001 af Runoff Area=16,580 sf 0.00% Impervious Runoff Depth=0.35"Subcatchment 3B: Flow Length=210' Tc=12.4 min CN=55 Runoff=0.10 cfs 0.011 af Runoff Area=10,745 sf 7.91% Impervious Runoff Depth=0.54"Subcatchment 3C: Flow Length=242' Tc=12.2 min CN=60 Runoff=0.14 cfs 0.011 af Peak Elev=365.21' Storage=334 cf Inflow=0.46 cfs 0.029 afPond P1: SMA#1 Discarded=0.08 cfs 0.029 af Primary=0.00 cfs 0.000 af Outflow=0.08 cfs 0.029 af Peak Elev=388.30' Storage=258 cf Inflow=0.38 cfs 0.029 afPond P2: SMA#2 Discarded=0.05 cfs 0.026 af Primary=0.14 cfs 0.003 af Outflow=0.19 cfs 0.029 af Peak Elev=392.98' Storage=76 cf Inflow=0.14 cfs 0.011 afPond P3: SMA#3 Discarded=0.04 cfs 0.011 af Primary=0.00 cfs 0.000 af Outflow=0.04 cfs 0.011 af Inflow=0.05 cfs 0.002 afLink 1: DRIVEWAY/LAKE Primary=0.05 cfs 0.002 af Inflow=0.15 cfs 0.005 afLink 2: NORTH Primary=0.15 cfs 0.005 af Inflow=0.11 cfs 0.013 afLink 3: ROAD Primary=0.11 cfs 0.013 af Total Runoff Area = 1.843 ac Runoff Volume = 0.086 af Average Runoff Depth = 0.56" 90.39% Pervious = 1.666 ac 9.61% Impervious = 0.177 ac Type II 24-hr 10 yr Rainfall=3.52"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 7HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment 1A: Runoff = 0.05 cfs @ 11.90 hrs, Volume= 0.002 af, Depth= 1.32" Routed to Link 1 : DRIVEWAY/LAKE Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=3.52" Area (sf) CN Description * 370 98 DRIVE PAVED 440 55 Woods, Good, HSG B 810 75 Weighted Average 440 54.32% Pervious Area 370 45.68% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.2 30 0.1500 2.14 Sheet Flow, Smooth surfaces n= 0.011 P2= 2.51" Summary for Subcatchment 1B: Runoff = 0.46 cfs @ 12.04 hrs, Volume= 0.029 af, Depth= 0.72" Routed to Pond P1 : SMA#1 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=3.52" Area (sf) CN Description 8,550 61 >75% Grass cover, Good, HSG B 9,040 55 Woods, Good, HSG B * 1,640 98 DRIVE PAVED * 1,800 98 PAVED COURT 21,030 64 Weighted Average 17,590 83.64% Pervious Area 3,440 16.36% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.3 100 0.2200 0.18 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.7 100 0.2000 2.24 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.2 95 0.1800 7.89 11.83 Trap/Vee/Rect Channel Flow, Bot.W=2.00' D=0.50' Z= 2.0 '/' Top.W=4.00' n= 0.040 Earth, cobble bottom, clean sides 10.2 295 Total Type II 24-hr 10 yr Rainfall=3.52"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 8HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment 2A: Runoff = 0.04 cfs @ 12.00 hrs, Volume= 0.002 af, Depth= 0.39" Routed to Link 2 : NORTH Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=3.52" Area (sf) CN Description 770 61 >75% Grass cover, Good, HSG B 2,520 55 Woods, Good, HSG B 3,290 56 Weighted Average 3,290 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.5 50 0.2000 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" Summary for Subcatchment 2B: Runoff = 0.38 cfs @ 12.08 hrs, Volume= 0.029 af, Depth= 0.58" Routed to Pond P2 : SMA#2 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=3.52" Area (sf) CN Description 4,840 61 >75% Grass cover, Good, HSG B 18,440 55 Woods, Good, HSG B * 2,280 98 DRIVE PAVED * 780 98 OFFSITE DRIVE 26,340 61 Weighted Average 23,280 88.38% Pervious Area 3,060 11.62% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.8 100 0.1500 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 1.1 140 0.1800 2.12 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.1 12 0.0200 2.87 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.8 130 0.0500 2.84 1.42 Trap/Vee/Rect Channel Flow, Bot.W=2.00' D=0.25' n= 0.040 Earth, cobble bottom, clean sides 12.8 382 Total Type II 24-hr 10 yr Rainfall=3.52"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 9HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment 3A: Runoff = 0.03 cfs @ 11.95 hrs, Volume= 0.001 af, Depth= 0.50" Routed to Link 3 : ROAD Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=3.52" Area (sf) CN Description 940 61 >75% Grass cover, Good, HSG B 560 55 Woods, Good, HSG B 1,500 59 Weighted Average 1,500 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.2 30 0.2500 0.22 Sheet Flow, Grass: Dense n= 0.240 P2= 2.51" 0.1 20 0.0500 4.54 Shallow Concentrated Flow, Paved Kv= 20.3 fps 2.3 50 Total Summary for Subcatchment 3B: Runoff = 0.10 cfs @ 12.10 hrs, Volume= 0.011 af, Depth= 0.35" Routed to Link 3 : ROAD Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=3.52" Area (sf) CN Description 16,580 55 Woods, Good, HSG B 16,580 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.5 100 0.1300 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.9 110 0.1500 1.94 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 12.4 210 Total Summary for Subcatchment 3C: Runoff = 0.14 cfs @ 12.07 hrs, Volume= 0.011 af, Depth= 0.54" Routed to Pond P3 : SMA#3 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=3.52" Type II 24-hr 10 yr Rainfall=3.52"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 10HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Area (sf) CN Description 2,725 61 >75% Grass cover, Good, HSG B 7,170 55 Woods, Good, HSG B * 850 98 DRIVE PAVED 10,745 60 Weighted Average 9,895 92.09% Pervious Area 850 7.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.1 100 0.1400 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.9 100 0.1500 1.94 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.1 22 0.1000 6.42 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.1 20 0.0500 5.38 9.42 Trap/Vee/Rect Channel Flow, Bot.W=2.00' D=0.50' Z= 3.0 '/' Top.W=5.00' n= 0.030 Earth, grassed & winding 12.2 242 Total Summary for Pond P1: SMA#1 Inflow Area = 0.483 ac, 16.36% Impervious, Inflow Depth = 0.72" for 10 yr event Inflow = 0.46 cfs @ 12.04 hrs, Volume= 0.029 af Outflow = 0.08 cfs @ 12.49 hrs, Volume= 0.029 af, Atten= 83%, Lag= 27.2 min Discarded = 0.08 cfs @ 12.49 hrs, Volume= 0.029 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routed to Link 1 : DRIVEWAY/LAKE Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Peak Elev= 365.21' @ 12.49 hrs Surf.Area= 665 sf Storage= 334 cf Plug-Flow detention time= 35.7 min calculated for 0.029 af (100% of inflow) Center-of-Mass det. time= 35.7 min ( 927.4 - 891.7 ) Volume Invert Avail.Storage Storage Description #1 364.50' 553 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 364.50 300 0 0 365.00 530 208 208 365.50 850 345 553 Device Routing Invert Outlet Devices #1 Discarded 364.50'5.000 in/hr Exfiltration over Surface area #2 Primary 365.40'5.0' 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 Type II 24-hr 10 yr Rainfall=3.52"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 11HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC 3.30 3.31 3.32 Discarded OutFlow Max=0.08 cfs @ 12.49 hrs HW=365.21' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.08 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=364.50' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Summary for Pond P2: SMA#2 Inflow Area = 0.605 ac, 11.62% Impervious, Inflow Depth = 0.58" for 10 yr event Inflow = 0.38 cfs @ 12.08 hrs, Volume= 0.029 af Outflow = 0.19 cfs @ 12.26 hrs, Volume= 0.029 af, Atten= 51%, Lag= 11.3 min Discarded = 0.05 cfs @ 12.27 hrs, Volume= 0.026 af Primary = 0.14 cfs @ 12.26 hrs, Volume= 0.003 af Routed to Link 2 : NORTH Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Peak Elev= 388.30' @ 12.27 hrs Surf.Area= 420 sf Storage= 258 cf Plug-Flow detention time= 41.4 min calculated for 0.029 af (100% of inflow) Center-of-Mass det. time= 41.4 min ( 949.0 - 907.6 ) Volume Invert Avail.Storage Storage Description #1 387.50' 349 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 387.50 240 0 0 388.00 340 145 145 388.50 475 204 349 Device Routing Invert Outlet Devices #1 Discarded 387.50'5.000 in/hr Exfiltration over Surface area #2 Primary 388.25'5.0' 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 Discarded OutFlow Max=0.05 cfs @ 12.27 hrs HW=388.29' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.05 cfs) Primary OutFlow Max=0.12 cfs @ 12.26 hrs HW=388.29' (Free Discharge) 2=Broad-Crested Rectangular Weir (Weir Controls 0.12 cfs @ 0.57 fps) Type II 24-hr 10 yr Rainfall=3.52"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 12HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Pond P3: SMA#3 Inflow Area = 0.247 ac, 7.91% Impervious, Inflow Depth = 0.54" for 10 yr event Inflow = 0.14 cfs @ 12.07 hrs, Volume= 0.011 af Outflow = 0.04 cfs @ 12.38 hrs, Volume= 0.011 af, Atten= 71%, Lag= 18.3 min Discarded = 0.04 cfs @ 12.38 hrs, Volume= 0.011 af Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routed to Link 3 : ROAD Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Peak Elev= 392.98' @ 12.38 hrs Surf.Area= 356 sf Storage= 76 cf Plug-Flow detention time= 10.0 min calculated for 0.011 af (100% of inflow) Center-of-Mass det. time= 10.0 min ( 922.1 - 912.1 ) Volume Invert Avail.Storage Storage Description #1 392.75' 418 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 392.75 310 0 0 393.00 360 84 84 393.75 530 334 418 Device Routing Invert Outlet Devices #1 Discarded 392.75'5.000 in/hr Exfiltration over Surface area #2 Primary 393.25'5.0' 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 Discarded OutFlow Max=0.04 cfs @ 12.38 hrs HW=392.98' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.04 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=392.75' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Summary for Link 1: DRIVEWAY/LAKE Inflow Area = 0.501 ac, 17.45% Impervious, Inflow Depth = 0.05" for 10 yr event Inflow = 0.05 cfs @ 11.90 hrs, Volume= 0.002 af Primary = 0.05 cfs @ 11.90 hrs, Volume= 0.002 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yr Rainfall=3.52"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 13HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Link 2: NORTH Inflow Area = 0.680 ac, 10.33% Impervious, Inflow Depth = 0.09" for 10 yr event Inflow = 0.15 cfs @ 12.26 hrs, Volume= 0.005 af Primary = 0.15 cfs @ 12.26 hrs, Volume= 0.005 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Summary for Link 3: ROAD Inflow Area = 0.662 ac, 2.95% Impervious, Inflow Depth = 0.23" for 10 yr event Inflow = 0.11 cfs @ 12.09 hrs, Volume= 0.013 af Primary = 0.11 cfs @ 12.09 hrs, Volume= 0.013 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 14HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Time span=0.00-100.00 hrs, dt=0.05 hrs, 2001 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=810 sf 45.68% Impervious Runoff Depth=1.87"Subcatchment 1A: Flow Length=30' Slope=0.1500 '/' Tc=0.2 min CN=75 Runoff=0.07 cfs 0.003 af Runoff Area=21,030 sf 16.36% Impervious Runoff Depth=1.13"Subcatchment 1B: Flow Length=295' Tc=10.2 min CN=64 Runoff=0.77 cfs 0.045 af Runoff Area=3,290 sf 0.00% Impervious Runoff Depth=0.69"Subcatchment 2A: Flow Length=50' Slope=0.2000 '/' Tc=5.5 min CN=56 Runoff=0.08 cfs 0.004 af Runoff Area=26,340 sf 11.62% Impervious Runoff Depth=0.95"Subcatchment 2B: Flow Length=382' Tc=12.8 min CN=61 Runoff=0.71 cfs 0.048 af Runoff Area=1,500 sf 0.00% Impervious Runoff Depth=0.84"Subcatchment 3A: Flow Length=50' Tc=2.3 min CN=59 Runoff=0.05 cfs 0.002 af Runoff Area=16,580 sf 0.00% Impervious Runoff Depth=0.64"Subcatchment 3B: Flow Length=210' Tc=12.4 min CN=55 Runoff=0.26 cfs 0.020 af Runoff Area=10,745 sf 7.91% Impervious Runoff Depth=0.90"Subcatchment 3C: Flow Length=242' Tc=12.2 min CN=60 Runoff=0.27 cfs 0.018 af Peak Elev=365.47' Storage=524 cf Inflow=0.77 cfs 0.045 afPond P1: SMA#1 Discarded=0.10 cfs 0.041 af Primary=0.23 cfs 0.004 af Outflow=0.32 cfs 0.045 af Peak Elev=388.39' Storage=300 cf Inflow=0.71 cfs 0.048 afPond P2: SMA#2 Discarded=0.05 cfs 0.034 af Primary=0.72 cfs 0.014 af Outflow=0.77 cfs 0.048 af Peak Elev=393.27' Storage=189 cf Inflow=0.27 cfs 0.018 afPond P3: SMA#3 Discarded=0.05 cfs 0.018 af Primary=0.04 cfs 0.001 af Outflow=0.09 cfs 0.018 af Inflow=0.23 cfs 0.007 afLink 1: DRIVEWAY/LAKE Primary=0.23 cfs 0.007 af Inflow=0.74 cfs 0.018 afLink 2: NORTH Primary=0.74 cfs 0.018 af Inflow=0.26 cfs 0.023 afLink 3: ROAD Primary=0.26 cfs 0.023 af Total Runoff Area = 1.843 ac Runoff Volume = 0.142 af Average Runoff Depth = 0.92" 90.39% Pervious = 1.666 ac 9.61% Impervious = 0.177 ac Type II 24-hr 25 yr Rainfall=4.27"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 15HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment 1A: Runoff = 0.07 cfs @ 11.90 hrs, Volume= 0.003 af, Depth= 1.87" Routed to Link 1 : DRIVEWAY/LAKE Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27" Area (sf) CN Description * 370 98 DRIVE PAVED 440 55 Woods, Good, HSG B 810 75 Weighted Average 440 54.32% Pervious Area 370 45.68% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.2 30 0.1500 2.14 Sheet Flow, Smooth surfaces n= 0.011 P2= 2.51" Summary for Subcatchment 1B: Runoff = 0.77 cfs @ 12.03 hrs, Volume= 0.045 af, Depth= 1.13" Routed to Pond P1 : SMA#1 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27" Area (sf) CN Description 8,550 61 >75% Grass cover, Good, HSG B 9,040 55 Woods, Good, HSG B * 1,640 98 DRIVE PAVED * 1,800 98 PAVED COURT 21,030 64 Weighted Average 17,590 83.64% Pervious Area 3,440 16.36% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.3 100 0.2200 0.18 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.7 100 0.2000 2.24 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.2 95 0.1800 7.89 11.83 Trap/Vee/Rect Channel Flow, Bot.W=2.00' D=0.50' Z= 2.0 '/' Top.W=4.00' n= 0.040 Earth, cobble bottom, clean sides 10.2 295 Total Type II 24-hr 25 yr Rainfall=4.27"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 16HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment 2A: Runoff = 0.08 cfs @ 11.99 hrs, Volume= 0.004 af, Depth= 0.69" Routed to Link 2 : NORTH Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27" Area (sf) CN Description 770 61 >75% Grass cover, Good, HSG B 2,520 55 Woods, Good, HSG B 3,290 56 Weighted Average 3,290 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.5 50 0.2000 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" Summary for Subcatchment 2B: Runoff = 0.71 cfs @ 12.07 hrs, Volume= 0.048 af, Depth= 0.95" Routed to Pond P2 : SMA#2 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27" Area (sf) CN Description 4,840 61 >75% Grass cover, Good, HSG B 18,440 55 Woods, Good, HSG B * 2,280 98 DRIVE PAVED * 780 98 OFFSITE DRIVE 26,340 61 Weighted Average 23,280 88.38% Pervious Area 3,060 11.62% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.8 100 0.1500 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 1.1 140 0.1800 2.12 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.1 12 0.0200 2.87 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.8 130 0.0500 2.84 1.42 Trap/Vee/Rect Channel Flow, Bot.W=2.00' D=0.25' n= 0.040 Earth, cobble bottom, clean sides 12.8 382 Total Type II 24-hr 25 yr Rainfall=4.27"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 17HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment 3A: Runoff = 0.05 cfs @ 11.94 hrs, Volume= 0.002 af, Depth= 0.84" Routed to Link 3 : ROAD Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27" Area (sf) CN Description 940 61 >75% Grass cover, Good, HSG B 560 55 Woods, Good, HSG B 1,500 59 Weighted Average 1,500 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.2 30 0.2500 0.22 Sheet Flow, Grass: Dense n= 0.240 P2= 2.51" 0.1 20 0.0500 4.54 Shallow Concentrated Flow, Paved Kv= 20.3 fps 2.3 50 Total Summary for Subcatchment 3B: Runoff = 0.26 cfs @ 12.07 hrs, Volume= 0.020 af, Depth= 0.64" Routed to Link 3 : ROAD Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27" Area (sf) CN Description 16,580 55 Woods, Good, HSG B 16,580 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.5 100 0.1300 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.9 110 0.1500 1.94 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 12.4 210 Total Summary for Subcatchment 3C: Runoff = 0.27 cfs @ 12.06 hrs, Volume= 0.018 af, Depth= 0.90" Routed to Pond P3 : SMA#3 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27" Type II 24-hr 25 yr Rainfall=4.27"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 18HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Area (sf) CN Description 2,725 61 >75% Grass cover, Good, HSG B 7,170 55 Woods, Good, HSG B * 850 98 DRIVE PAVED 10,745 60 Weighted Average 9,895 92.09% Pervious Area 850 7.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 11.1 100 0.1400 0.15 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.51" 0.9 100 0.1500 1.94 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.1 22 0.1000 6.42 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.1 20 0.0500 5.38 9.42 Trap/Vee/Rect Channel Flow, Bot.W=2.00' D=0.50' Z= 3.0 '/' Top.W=5.00' n= 0.030 Earth, grassed & winding 12.2 242 Total Summary for Pond P1: SMA#1 Inflow Area = 0.483 ac, 16.36% Impervious, Inflow Depth = 1.13" for 25 yr event Inflow = 0.77 cfs @ 12.03 hrs, Volume= 0.045 af Outflow = 0.32 cfs @ 12.19 hrs, Volume= 0.045 af, Atten= 58%, Lag= 9.6 min Discarded = 0.10 cfs @ 12.19 hrs, Volume= 0.041 af Primary = 0.23 cfs @ 12.19 hrs, Volume= 0.004 af Routed to Link 1 : DRIVEWAY/LAKE Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Peak Elev= 365.47' @ 12.19 hrs Surf.Area= 828 sf Storage= 524 cf Plug-Flow detention time= 44.2 min calculated for 0.045 af (100% of inflow) Center-of-Mass det. time= 44.2 min ( 919.5 - 875.2 ) Volume Invert Avail.Storage Storage Description #1 364.50' 553 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 364.50 300 0 0 365.00 530 208 208 365.50 850 345 553 Device Routing Invert Outlet Devices #1 Discarded 364.50'5.000 in/hr Exfiltration over Surface area #2 Primary 365.40'5.0' 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 Type II 24-hr 25 yr Rainfall=4.27"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 19HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC 3.30 3.31 3.32 Discarded OutFlow Max=0.10 cfs @ 12.19 hrs HW=365.46' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.10 cfs) Primary OutFlow Max=0.22 cfs @ 12.19 hrs HW=365.46' (Free Discharge) 2=Broad-Crested Rectangular Weir (Weir Controls 0.22 cfs @ 0.68 fps) Summary for Pond P2: SMA#2 Inflow Area = 0.605 ac, 11.62% Impervious, Inflow Depth = 0.95" for 25 yr event Inflow = 0.71 cfs @ 12.07 hrs, Volume= 0.048 af Outflow = 0.77 cfs @ 12.11 hrs, Volume= 0.048 af, Atten= 0%, Lag= 2.9 min Discarded = 0.05 cfs @ 12.12 hrs, Volume= 0.034 af Primary = 0.72 cfs @ 12.11 hrs, Volume= 0.014 af Routed to Link 2 : NORTH Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Peak Elev= 388.39' @ 12.12 hrs Surf.Area= 446 sf Storage= 300 cf Plug-Flow detention time= 38.3 min calculated for 0.048 af (100% of inflow) Center-of-Mass det. time= 38.3 min ( 926.4 - 888.1 ) Volume Invert Avail.Storage Storage Description #1 387.50' 349 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 387.50 240 0 0 388.00 340 145 145 388.50 475 204 349 Device Routing Invert Outlet Devices #1 Discarded 387.50'5.000 in/hr Exfiltration over Surface area #2 Primary 388.25'5.0' 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 Discarded OutFlow Max=0.05 cfs @ 12.12 hrs HW=388.38' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.05 cfs) Primary OutFlow Max=0.63 cfs @ 12.11 hrs HW=388.38' (Free Discharge) 2=Broad-Crested Rectangular Weir (Weir Controls 0.63 cfs @ 0.97 fps) Type II 24-hr 25 yr Rainfall=4.27"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 20HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Pond P3: SMA#3 Inflow Area = 0.247 ac, 7.91% Impervious, Inflow Depth = 0.90" for 25 yr event Inflow = 0.27 cfs @ 12.06 hrs, Volume= 0.018 af Outflow = 0.09 cfs @ 12.32 hrs, Volume= 0.018 af, Atten= 69%, Lag= 15.4 min Discarded = 0.05 cfs @ 12.32 hrs, Volume= 0.018 af Primary = 0.04 cfs @ 12.32 hrs, Volume= 0.001 af Routed to Link 3 : ROAD Routing by Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Peak Elev= 393.27' @ 12.32 hrs Surf.Area= 421 sf Storage= 189 cf Plug-Flow detention time= 25.8 min calculated for 0.018 af (100% of inflow) Center-of-Mass det. time= 25.8 min ( 917.1 - 891.4 ) Volume Invert Avail.Storage Storage Description #1 392.75' 418 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 392.75 310 0 0 393.00 360 84 84 393.75 530 334 418 Device Routing Invert Outlet Devices #1 Discarded 392.75'5.000 in/hr Exfiltration over Surface area #2 Primary 393.25'5.0' 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 Discarded OutFlow Max=0.05 cfs @ 12.32 hrs HW=393.27' (Free Discharge) 1=Exfiltration (Exfiltration Controls 0.05 cfs) Primary OutFlow Max=0.03 cfs @ 12.32 hrs HW=393.27' (Free Discharge) 2=Broad-Crested Rectangular Weir (Weir Controls 0.03 cfs @ 0.37 fps) Summary for Link 1: DRIVEWAY/LAKE Inflow Area = 0.501 ac, 17.45% Impervious, Inflow Depth = 0.17" for 25 yr event Inflow = 0.23 cfs @ 12.19 hrs, Volume= 0.007 af Primary = 0.23 cfs @ 12.19 hrs, Volume= 0.007 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yr Rainfall=4.27"POST-DEVELOPMENT Printed 8/30/2022Prepared by {enter your company name here} Page 21HydroCAD® 10.10-7b s/n 11387 © 2022 HydroCAD Software Solutions LLC Summary for Link 2: NORTH Inflow Area = 0.680 ac, 10.33% Impervious, Inflow Depth = 0.33" for 25 yr event Inflow = 0.74 cfs @ 12.11 hrs, Volume= 0.018 af Primary = 0.74 cfs @ 12.11 hrs, Volume= 0.018 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Summary for Link 3: ROAD Inflow Area = 0.662 ac, 2.95% Impervious, Inflow Depth = 0.42" for 25 yr event Inflow = 0.26 cfs @ 12.07 hrs, Volume= 0.023 af Primary = 0.26 cfs @ 12.07 hrs, Volume= 0.023 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.05 hrs Stormwater Management Narrative Driveway Access - Griffey Town of Queensbury, New York 900 New York 146 Clifton Park, NY 12065 (P) 518.371.7621 (F) 518.371.9540 edpllp.com Appendix D Draft Stormwater Maintenance Agreement STORMWATER MANAGEMENT 147 Attachment 5 SCHEDULE E Sample Stormwater Control Facility Maintenance Agreement Whereas, the Town of Queensbury ('municipality') and (the "facility owner") want to enter into an agreement to provide for the long term maintenance and continuation of stormwater control measures approved by the municipality for the below named project, and Whereas, the municipality and the facility owner desire that the stormwater control measures be built in accordance with the approved project plans and thereafter be maintained, cleaned, repaired, replaced and continued in perpetuity in order to ensure optimum performance of the components. Therefore, the municipality and the facility owner agree as follows: 1.This agreement binds the municipality and the facility owner, its successors and assigns, to the maintenance provisions depicted in the approved project plans which are attached as Schedule A of this agreement. 2.The facility owner shall maintain, clean, repair, replace and continue the stormwater control measures depicted in Schedule A as necessary to ensure optimum performance of the measures to design specifications. The stormwater control measures shall include, but shall not be limited to, the following: drainage ditches, swales, dry wells, infiltrators, drop inlets, pipes, culverts, soil absorption devices and retention ponds. 3.The facility owner shall be responsible for all expenses related to the maintenance of the stormwater control measures and shall establish a means for the collection and distribution of expenses among parties for any commonly owned facilities. 4.The facility owner shall provide for the periodic inspection of the stormwater control measures, not less than once in every five year period, to determine the condition and integrity of the measures. Such inspection shall be performed by a Professional Engineer licensed by the State of New York. The inspecting engineer shall prepare and submit to the municipality within 30 days of the inspection, a written report of the findings including recommendations for those actions necessary for the continuation of the stormwater control measures. 5.The facility owner shall not authorize, undertake or permit alteration, abandonment, modification or discontinuation of the stormwater control measures except in accordance with written approval of the municipality. 6.The facility owner shall undertake necessary repairs and replacement of the stormwater control measures at the direction of the municipality or in accordance with the recommendations of the inspecting engineer. 7.The facility owner shall provide to the municipality within 30 days of the date of this agreement, a security for the maintenance and continuation of the stormwater control measures in the form of a (Bond, letter of credit or escrow account). 147 Attachment 5:1 04 - 15 - 2009 QUEENSBURY CODE 8.This agreement shall be recorded in the Office of the County Clerk, County of Warren, together with the deed for the common property and shall be included in the offering plan and/or prospectus approved pursuant to _________________. 9.If ever the municipality determines that the facility owner has failed to construct or maintain the stormwater control measures in accordance with the project plan or has failed to undertake corrective action specified by the municipality or by the inspecting engineer, the municipality is authorized to undertake such steps as reasonably necessary for the preservation, continuation or maintenance of the stormwater control measures and to affix the expenses thereof as a lien against the property. 10.This agreement is effective beginning on: _________________. 147 Attachment 5:2 04 - 15 - 2009