Loading...
HydroCAD Report (All Storms) Revised 3-19-21 (1)1S A1 2S A2 3S A3 4S A4 5S B2 6S POND 7S PRE REAR 8S A5 9S A6 10S A7 11S A8 12S A9 13S A10 14S A11 15S A12 16S A13 17S A14 18S A15 19S B1 20S PRE FRONT 1CCB CB1 1D CB DMH1 1P POST REAR 2CCB CB2 2D CB DMH2 2P POST FRONT 3C CB CB3 3D CB DMH3 4CCB CB4 9P RG9 12P RG12 13P RG13 14P RG14 15P RG1516P INF-10+11 17P INF-6+8 18P INF-5+7 Routing Diagram for 2018-082 Colvest Northampton As-Built Modifications Prepared by J.R. Russo & Associates, LLC, Printed 3/19/2021 HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Subcat Reach Pond Link Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 2HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Time span=1.00-20.00 hrs, dt=0.01 hrs, 1901 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Runoff Area=8,350 sf 98.42% Impervious Runoff Depth>2.02"Subcatchment 1S: A1 Tc=5.0 min CN=97 Runoff=0.46 cfs 0.032 af Runoff Area=4,496 sf 92.70% Impervious Runoff Depth>1.82"Subcatchment 2S: A2 Tc=5.0 min CN=95 Runoff=0.23 cfs 0.016 af Runoff Area=6,870 sf 97.82% Impervious Runoff Depth>2.02"Subcatchment 3S: A3 Tc=5.0 min CN=97 Runoff=0.38 cfs 0.027 af Runoff Area=8,648 sf 82.34% Impervious Runoff Depth>1.48"Subcatchment 4S: A4 Tc=5.0 min CN=91 Runoff=0.38 cfs 0.024 af Runoff Area=25,964 sf 100.00% Impervious Runoff Depth>2.12"Subcatchment 5S: B2 Tc=5.0 min CN=98 Runoff=1.46 cfs 0.105 af Runoff Area=7,072 sf 0.00% Impervious Runoff Depth>0.15"Subcatchment 6S: POND Tc=0.0 min CN=61 Runoff=0.01 cfs 0.002 af Runoff Area=57,882 sf 0.00% Impervious Runoff Depth>1.48"Subcatchment 7S: PRE REAR Tc=5.0 min CN=91 Runoff=2.53 cfs 0.163 af Runoff Area=5,095 sf 91.89% Impervious Runoff Depth>1.82"Subcatchment 8S: A5 Tc=5.0 min CN=95 Runoff=0.26 cfs 0.018 af Runoff Area=6,947 sf 89.75% Impervious Runoff Depth>1.73"Subcatchment 9S: A6 Tc=5.0 min CN=94 Runoff=0.35 cfs 0.023 af Runoff Area=4,230 sf 90.85% Impervious Runoff Depth>1.82"Subcatchment 10S: A7 Tc=5.0 min CN=95 Runoff=0.22 cfs 0.015 af Runoff Area=5,823 sf 87.02% Impervious Runoff Depth>1.64"Subcatchment 11S: A8 Tc=5.0 min CN=93 Runoff=0.28 cfs 0.018 af Runoff Area=11,231 sf 77.08% Impervious Runoff Depth>1.40"Subcatchment 12S: A9 Tc=5.0 min CN=90 Runoff=0.47 cfs 0.030 af Runoff Area=9,635 sf 93.98% Impervious Runoff Depth>1.92"Subcatchment 13S: A10 Tc=5.0 min CN=96 Runoff=0.51 cfs 0.035 af Runoff Area=6,395 sf 85.41% Impervious Runoff Depth>1.64"Subcatchment 14S: A11 Tc=5.0 min CN=93 Runoff=0.31 cfs 0.020 af Runoff Area=9,957 sf 48.28% Impervious Runoff Depth>0.74"Subcatchment 15S: A12 Tc=5.0 min CN=79 Runoff=0.21 cfs 0.014 af Runoff Area=3,453 sf 73.59% Impervious Runoff Depth>1.26"Subcatchment 16S: A13 Tc=5.0 min CN=88 Runoff=0.13 cfs 0.008 af Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 3HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Runoff Area=2,168 sf 59.73% Impervious Runoff Depth>0.95"Subcatchment 17S: A14 Tc=5.0 min CN=83 Runoff=0.06 cfs 0.004 af Runoff Area=2,826 sf 51.91% Impervious Runoff Depth>0.79"Subcatchment 18S: A15 Tc=5.0 min CN=80 Runoff=0.07 cfs 0.004 af Runoff Area=6,971 sf 100.00% Impervious Runoff Depth>2.12"Subcatchment 19S: B1 Tc=5.0 min CN=98 Runoff=0.39 cfs 0.028 af Runoff Area=71,761 sf 44.08% Impervious Runoff Depth>1.33"Subcatchment 20S: PRE FRONT Tc=5.0 min CN=89 Runoff=2.84 cfs 0.182 af Peak Elev=145.18' Inflow=0.46 cfs 0.032 afPond 1C: CB1 12.0" Round Culvert n=0.012 L=124.0' S=0.0050 '/' Outflow=0.46 cfs 0.032 af Peak Elev=144.77' Inflow=2.15 cfs 0.153 afPond 1D: DMH1 18.0" Round Culvert n=0.012 L=58.0' S=0.0050 '/' Outflow=2.15 cfs 0.153 af Peak Elev=145.66' Storage=6,034 cf Inflow=2.92 cfs 0.206 afPond 1P: POST REAR Discarded=0.09 cfs 0.080 af Primary=0.00 cfs 0.000 af Outflow=0.09 cfs 0.080 af Peak Elev=145.23' Inflow=0.23 cfs 0.016 afPond 2C: CB2 12.0" Round Culvert n=0.012 L=8.0' S=0.0437 '/' Outflow=0.23 cfs 0.016 af Peak Elev=144.48' Inflow=2.53 cfs 0.180 afPond 2D: DMH2 18.0" Round Culvert n=0.012 L=50.0' S=0.0050 '/' Outflow=2.53 cfs 0.180 af Peak Elev=145.11' Storage=3,834 cf Inflow=3.48 cfs 0.131 afPond 2P: POST FRONT Outflow=0.83 cfs 0.099 af Peak Elev=145.12' Inflow=0.38 cfs 0.027 afPond 3C: CB3 12.0" Round Culvert n=0.012 L=13.0' S=0.0115 '/' Outflow=0.38 cfs 0.027 af Peak Elev=144.21' Inflow=2.91 cfs 0.204 afPond 3D: DMH3 18.0" Round Culvert n=0.012 L=54.0' S=0.0056 '/' Outflow=2.91 cfs 0.204 af Peak Elev=145.11' Inflow=0.38 cfs 0.024 afPond 4C: CB4 12.0" Round Culvert n=0.012 L=8.0' S=0.0188 '/' Outflow=0.38 cfs 0.024 af Peak Elev=146.82' Storage=41 cf Inflow=0.47 cfs 0.030 afPond 9P: RG9 Discarded=0.00 cfs 0.002 af Primary=0.43 cfs 0.028 af Outflow=0.43 cfs 0.030 af Peak Elev=146.40' Storage=13 cf Inflow=0.21 cfs 0.014 afPond 12P: RG12 Discarded=0.00 cfs 0.001 af Primary=0.20 cfs 0.013 af Outflow=0.21 cfs 0.014 af Peak Elev=146.26' Storage=4 cf Inflow=0.13 cfs 0.008 afPond 13P: RG13 Discarded=0.00 cfs 0.001 af Primary=0.13 cfs 0.007 af Outflow=0.13 cfs 0.008 af Peak Elev=146.16' Storage=4 cf Inflow=0.06 cfs 0.004 afPond 14P: RG14 Discarded=0.00 cfs 0.001 af Primary=0.06 cfs 0.003 af Outflow=0.06 cfs 0.004 af Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 4HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev=146.17' Storage=4 cf Inflow=0.07 cfs 0.004 afPond 15P: RG15 Discarded=0.00 cfs 0.001 af Primary=0.06 cfs 0.003 af Outflow=0.06 cfs 0.004 af Peak Elev=147.23' Storage=493 cf Inflow=0.82 cfs 0.055 afPond 16P: INF-10+11 Discarded=0.03 cfs 0.028 af Primary=0.92 cfs 0.020 af Outflow=0.96 cfs 0.049 af Peak Elev=146.96' Storage=323 cf Inflow=0.62 cfs 0.041 afPond 17P: INF-6+8 Discarded=0.02 cfs 0.018 af Primary=0.59 cfs 0.019 af Outflow=0.62 cfs 0.037 af Peak Elev=146.96' Storage=357 cf Inflow=0.48 cfs 0.032 afPond 18P: INF-5+7 Discarded=0.03 cfs 0.021 af Primary=0.75 cfs 0.008 af Outflow=0.78 cfs 0.029 af Total Runoff Area = 6.101 ac Runoff Volume = 0.770 af Average Runoff Depth = 1.51" 45.85% Pervious = 2.798 ac 54.15% Impervious = 3.304 ac Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 5HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: A1 Runoff = 0.46 cfs @ 12.07 hrs, Volume= 0.032 af, Depth> 2.02" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 8,218 98 Paved parking, HSG B 132 61 >75% Grass cover, Good, HSG B 8,350 97 Weighted Average 132 1.58% Pervious Area 8,218 98.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: A2 Runoff = 0.23 cfs @ 12.07 hrs, Volume= 0.016 af, Depth> 1.82" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 4,168 98 Paved parking, HSG B 328 61 >75% Grass cover, Good, HSG B 4,496 95 Weighted Average 328 7.30% Pervious Area 4,168 92.70% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 3S: A3 Runoff = 0.38 cfs @ 12.07 hrs, Volume= 0.027 af, Depth> 2.02" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 6,720 98 Paved parking, HSG B 150 61 >75% Grass cover, Good, HSG B 6,870 97 Weighted Average 150 2.18% Pervious Area 6,720 97.82% Impervious Area Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 6HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 4S: A4 Runoff = 0.38 cfs @ 12.07 hrs, Volume= 0.024 af, Depth> 1.48" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 7,121 98 Paved parking, HSG B 1,527 61 >75% Grass cover, Good, HSG B 8,648 91 Weighted Average 1,527 17.66% Pervious Area 7,121 82.34% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: B2 Runoff = 1.46 cfs @ 12.07 hrs, Volume= 0.105 af, Depth> 2.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 25,964 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 25,964 98 Weighted Average 25,964 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 6S: POND Runoff = 0.01 cfs @ 12.25 hrs, Volume= 0.002 af, Depth> 0.15" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 7HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 7,072 61 >75% Grass cover, Good, HSG B 7,072 100.00% Pervious Area Summary for Subcatchment 7S: PRE REAR Runoff = 2.53 cfs @ 12.07 hrs, Volume= 0.163 af, Depth> 1.48" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 9,064 67 Brush, Poor, HSG B 48,818 96 Gravel surface, HSG B 57,882 91 Weighted Average 57,882 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 8S: A5 Runoff = 0.26 cfs @ 12.07 hrs, Volume= 0.018 af, Depth> 1.82" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 4,682 98 Paved parking, HSG B 413 61 >75% Grass cover, Good, HSG B 5,095 95 Weighted Average 413 8.11% Pervious Area 4,682 91.89% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: A6 Runoff = 0.35 cfs @ 12.07 hrs, Volume= 0.023 af, Depth> 1.73" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 8HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 6,235 98 Paved parking, HSG B 712 61 >75% Grass cover, Good, HSG B 6,947 94 Weighted Average 712 10.25% Pervious Area 6,235 89.75% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 10S: A7 Runoff = 0.22 cfs @ 12.07 hrs, Volume= 0.015 af, Depth> 1.82" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 3,843 98 Paved parking, HSG B 387 61 >75% Grass cover, Good, HSG B 4,230 95 Weighted Average 387 9.15% Pervious Area 3,843 90.85% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 11S: A8 Runoff = 0.28 cfs @ 12.07 hrs, Volume= 0.018 af, Depth> 1.64" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 5,067 98 Paved parking, HSG B 756 61 >75% Grass cover, Good, HSG B 5,823 93 Weighted Average 756 12.98% Pervious Area 5,067 87.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 9HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 12S: A9 Runoff = 0.47 cfs @ 12.07 hrs, Volume= 0.030 af, Depth> 1.40" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 8,657 98 Paved parking, HSG B 2,574 61 >75% Grass cover, Good, HSG B 11,231 90 Weighted Average 2,574 22.92% Pervious Area 8,657 77.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 13S: A10 Runoff = 0.51 cfs @ 12.07 hrs, Volume= 0.035 af, Depth> 1.92" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 9,055 98 Paved parking, HSG B 580 61 >75% Grass cover, Good, HSG B 9,635 96 Weighted Average 580 6.02% Pervious Area 9,055 93.98% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 14S: A11 Runoff = 0.31 cfs @ 12.07 hrs, Volume= 0.020 af, Depth> 1.64" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 5,462 98 Paved parking, HSG B 933 61 >75% Grass cover, Good, HSG B 6,395 93 Weighted Average 933 14.59% Pervious Area 5,462 85.41% Impervious Area Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 10HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 15S: A12 Runoff = 0.21 cfs @ 12.08 hrs, Volume= 0.014 af, Depth> 0.74" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 4,807 98 Paved parking, HSG B 5,150 61 >75% Grass cover, Good, HSG B 9,957 79 Weighted Average 5,150 51.72% Pervious Area 4,807 48.28% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 16S: A13 Runoff = 0.13 cfs @ 12.08 hrs, Volume= 0.008 af, Depth> 1.26" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 2,541 98 Paved parking, HSG B 912 61 >75% Grass cover, Good, HSG B 3,453 88 Weighted Average 912 26.41% Pervious Area 2,541 73.59% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 17S: A14 Runoff = 0.06 cfs @ 12.08 hrs, Volume= 0.004 af, Depth> 0.95" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 11HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 1,295 98 Paved parking, HSG B 873 61 >75% Grass cover, Good, HSG B 2,168 83 Weighted Average 873 40.27% Pervious Area 1,295 59.73% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 18S: A15 Runoff = 0.07 cfs @ 12.08 hrs, Volume= 0.004 af, Depth> 0.79" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 1,467 98 Paved parking, HSG B 1,359 61 >75% Grass cover, Good, HSG B 2,826 80 Weighted Average 1,359 48.09% Pervious Area 1,467 51.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 19S: B1 Runoff = 0.39 cfs @ 12.07 hrs, Volume= 0.028 af, Depth> 2.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 6,971 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 6,971 98 Weighted Average 6,971 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 12HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 20S: PRE FRONT Runoff = 2.84 cfs @ 12.07 hrs, Volume= 0.182 af, Depth> 1.33" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46" Area (sf) CN Description 24,527 96 Gravel surface, HSG B 15,601 61 >75% Grass cover, Good, HSG B 31,633 98 Paved parking, HSG B 71,761 89 Weighted Average 40,128 55.92% Pervious Area 31,633 44.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Pond 1C: CB1 Inflow Area = 0.192 ac, 98.42% Impervious, Inflow Depth > 2.02" for 1-Year event Inflow = 0.46 cfs @ 12.07 hrs, Volume= 0.032 af Outflow = 0.46 cfs @ 12.07 hrs, Volume= 0.032 af, Atten= 0%, Lag= 0.0 min Primary = 0.46 cfs @ 12.07 hrs, Volume= 0.032 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.18' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 124.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.46 cfs @ 12.07 hrs HW=145.18' (Free Discharge) 1=Culvert (Barrel Controls 0.46 cfs @ 2.50 fps) Summary for Pond 1D: DMH1 Inflow Area = 0.891 ac, 98.81% Impervious, Inflow Depth > 2.07" for 1-Year event Inflow = 2.15 cfs @ 12.07 hrs, Volume= 0.153 af Outflow = 2.15 cfs @ 12.07 hrs, Volume= 0.153 af, Atten= 0%, Lag= 0.0 min Primary = 2.15 cfs @ 12.07 hrs, Volume= 0.153 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 144.77' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.00'18.0" Round 18" CPEP Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 13HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 58.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.00' / 143.71' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=2.15 cfs @ 12.07 hrs HW=144.77' (Free Discharge) 1=18" CPEP (Barrel Controls 2.15 cfs @ 3.42 fps) Summary for Pond 1P: POST REAR Inflow Area = 1.410 ac, 85.00% Impervious, Inflow Depth > 1.76" for 1-Year event Inflow = 2.92 cfs @ 12.07 hrs, Volume= 0.206 af Outflow = 0.09 cfs @ 15.70 hrs, Volume= 0.080 af, Atten= 97%, Lag= 218.0 min Discarded = 0.09 cfs @ 15.70 hrs, Volume= 0.080 af Primary = 0.00 cfs @ 1.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.66' @ 15.70 hrs Surf.Area= 3,326 sf Storage= 6,034 cf Plug-Flow detention time= 224.6 min calculated for 0.080 af (39% of inflow) Center-of-Mass det. time= 108.2 min ( 853.3 - 745.1 ) Volume Invert Avail.Storage Storage Description #1 143.00' 11,310 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 143.00 1,320 0 0 144.00 1,986 1,653 1,653 145.00 2,752 2,369 4,022 146.00 3,619 3,186 7,208 147.00 4,586 4,103 11,310 Device Routing Invert Outlet Devices #1 Discarded 143.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 135.00' #2 Primary 146.50'12.0' long x 16.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Discarded OutFlow Max=0.09 cfs @ 15.70 hrs HW=145.66' (Free Discharge) 1=Exfiltration ( Controls 0.09 cfs) Primary OutFlow Max=0.00 cfs @ 1.00 hrs HW=143.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 14HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 2C: CB2 Inflow Area = 0.103 ac, 92.70% Impervious, Inflow Depth > 1.82" for 1-Year event Inflow = 0.23 cfs @ 12.07 hrs, Volume= 0.016 af Outflow = 0.23 cfs @ 12.07 hrs, Volume= 0.016 af, Atten= 0%, Lag= 0.0 min Primary = 0.23 cfs @ 12.07 hrs, Volume= 0.016 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.23' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 145.00'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.00' / 144.65' S= 0.0437 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.23 cfs @ 12.07 hrs HW=145.23' (Free Discharge) 1=Culvert (Inlet Controls 0.23 cfs @ 1.65 fps) Summary for Pond 2D: DMH2 Inflow Area = 1.049 ac, 98.66% Impervious, Inflow Depth > 2.06" for 1-Year event Inflow = 2.53 cfs @ 12.07 hrs, Volume= 0.180 af Outflow = 2.53 cfs @ 12.07 hrs, Volume= 0.180 af, Atten= 0%, Lag= 0.0 min Primary = 2.53 cfs @ 12.07 hrs, Volume= 0.180 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 144.48' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.63'18.0" Round 18" CPEP L= 50.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.63' / 143.38' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=2.53 cfs @ 12.07 hrs HW=144.48' (Free Discharge) 1=18" CPEP (Barrel Controls 2.53 cfs @ 3.52 fps) Summary for Pond 2P: POST FRONT Inflow Area = 1.716 ac, 80.40% Impervious, Inflow Depth > 0.92" for 1-Year event Inflow = 3.48 cfs @ 12.08 hrs, Volume= 0.131 af Outflow = 0.83 cfs @ 12.42 hrs, Volume= 0.099 af, Atten= 76%, Lag= 20.5 min Primary = 0.83 cfs @ 12.42 hrs, Volume= 0.099 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Starting Elev= 144.27' Surf.Area= 2,195 sf Storage= 940 cf Peak Elev= 145.11' @ 12.42 hrs Surf.Area= 3,858 sf Storage= 3,834 cf (2,894 cf above start) Flood Elev= 148.20' Surf.Area= 508 sf Storage= 8,258 cf (7,318 cf above start) Plug-Flow detention time= 144.5 min calculated for 0.077 af (59% of inflow) Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 15HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Center-of-Mass det. time= 66.5 min ( 826.5 - 760.0 ) Volume Invert Avail.Storage Storage Description #1 143.90' 509 cf 4.00'D x 4.50'H DMH x 9 #2 143.86' 226 cf 30.0" Round 30" Flat CPEP (10-11) L= 46.0' S= 0.0070 '/' #3 143.74' 324 cf 30.0" Round 30" Flat CPEP (11-12) L= 66.0' S= 0.0003 '/' #4 143.78' 275 cf 30.0" Round 30" Flat CPEP (12-Out) L= 56.0' S= 0.0016 '/' #5 143.88' 1,924 cf 30.0" Round 30" Flat CPEP (9-Out) x 4 L= 98.0' S= 0.0030 '/' #6 143.39' 1,031 cf 30.0" Round 30" Flat CPEP (6-9) x 3 L= 70.0' S= 0.0007 '/' #7 143.59' 260 cf 30.0" Round 30" Flat CPEP (8-9) L= 53.0' S= 0.0008 '/' #8 143.38' 476 cf 30.0" Round 30" Flat CPEP (7-8) L= 97.0' S= 0.0008 '/' #9 143.39' 285 cf 30.0" Round 30" Flat CPEP (5-6) L= 58.0' S= 0.0007 '/' #10 143.50' 422 cf 30.0" Round 30" Flat CPEP (4-5) L= 86.0' S= 0.0003 '/' #11 148.00' 333 cf Custom Stage Data (Prismatic) Listed below (Recalc) #12 144.27' 2,376 cf 30.0" Round Prop. 30" Flat CPEP L= 484.0' #13 144.27' 113 cf 4.00'D x 4.50'H Prop. DMH x 2 8,554 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 370 0 0 148.90 370 333 333 Device Routing Invert Outlet Devices #1 Device 3 144.27'10.0" Vert. 10" Orifice C= 0.600 #2 Device 3 146.85'36.0" W x 4.0" H Vert. 4"x36" Weir/Orifice C= 0.600 #3 Primary 144.65'12.0" Round 12" Culvert L= 16.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.65' / 143.50' S= 0.0719 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Primary 148.00'37.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=0.83 cfs @ 12.42 hrs HW=145.11' (Free Discharge) 3=12" Culvert (Inlet Controls 0.83 cfs @ 2.32 fps) 1=10" Orifice (Passes 0.83 cfs of 1.72 cfs potential flow) 2=4"x36" Weir/Orifice ( Controls 0.00 cfs) 4=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 16HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 3C: CB3 Inflow Area = 0.158 ac, 97.82% Impervious, Inflow Depth > 2.02" for 1-Year event Inflow = 0.38 cfs @ 12.07 hrs, Volume= 0.027 af Outflow = 0.38 cfs @ 12.07 hrs, Volume= 0.027 af, Atten= 0%, Lag= 0.0 min Primary = 0.38 cfs @ 12.07 hrs, Volume= 0.027 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.12' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 13.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0115 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.38 cfs @ 12.07 hrs HW=145.12' (Free Discharge) 1=Culvert (Barrel Controls 0.38 cfs @ 2.58 fps) Summary for Pond 3D: DMH3 Inflow Area = 1.247 ac, 96.07% Impervious, Inflow Depth > 1.97" for 1-Year event Inflow = 2.91 cfs @ 12.07 hrs, Volume= 0.204 af Outflow = 2.91 cfs @ 12.07 hrs, Volume= 0.204 af, Atten= 0%, Lag= 0.0 min Primary = 2.91 cfs @ 12.07 hrs, Volume= 0.204 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 144.21' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.30'18.0" Round Culvert L= 54.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.30' / 143.00' S= 0.0056 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=2.91 cfs @ 12.07 hrs HW=144.20' (Free Discharge) 1=Culvert (Barrel Controls 2.91 cfs @ 3.74 fps) Summary for Pond 4C: CB4 Inflow Area = 0.199 ac, 82.34% Impervious, Inflow Depth > 1.48" for 1-Year event Inflow = 0.38 cfs @ 12.07 hrs, Volume= 0.024 af Outflow = 0.38 cfs @ 12.07 hrs, Volume= 0.024 af, Atten= 0%, Lag= 0.0 min Primary = 0.38 cfs @ 12.07 hrs, Volume= 0.024 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.11' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 17HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0188 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.38 cfs @ 12.07 hrs HW=145.11' (Free Discharge) 1=Culvert (Barrel Controls 0.38 cfs @ 2.72 fps) Summary for Pond 9P: RG9 Inflow Area = 0.258 ac, 77.08% Impervious, Inflow Depth > 1.40" for 1-Year event Inflow = 0.47 cfs @ 12.07 hrs, Volume= 0.030 af Outflow = 0.43 cfs @ 12.11 hrs, Volume= 0.030 af, Atten= 7%, Lag= 2.0 min Discarded = 0.00 cfs @ 12.11 hrs, Volume= 0.002 af Primary = 0.43 cfs @ 12.11 hrs, Volume= 0.028 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.82' @ 12.11 hrs Surf.Area= 68 sf Storage= 41 cf Flood Elev= 148.40' Surf.Area= 1,804 sf Storage= 1,004 cf Plug-Flow detention time= 1.5 min calculated for 0.030 af (100% of inflow) Center-of-Mass det. time= 1.1 min ( 783.6 - 782.5 ) Volume Invert Avail.Storage Storage Description #1 147.40' 963 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 145.60' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 145.60' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,004 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.40 632 0 0 148.00 853 445 445 148.40 1,736 518 963 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 145.60'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 34.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 143.94' S= 0.0165 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 145.60'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 18HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.00 cfs @ 12.11 hrs HW=146.81' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.43 cfs @ 12.11 hrs HW=146.81' (Free Discharge) 3=Culvert (Passes 0.43 cfs of 5.09 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.43 cfs @ 4.93 fps) Summary for Pond 12P: RG12 Inflow Area = 0.229 ac, 48.28% Impervious, Inflow Depth > 0.74" for 1-Year event Inflow = 0.21 cfs @ 12.08 hrs, Volume= 0.014 af Outflow = 0.21 cfs @ 12.10 hrs, Volume= 0.014 af, Atten= 4%, Lag= 1.3 min Discarded = 0.00 cfs @ 12.10 hrs, Volume= 0.001 af Primary = 0.20 cfs @ 12.10 hrs, Volume= 0.013 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.40' @ 12.10 hrs Surf.Area= 68 sf Storage= 13 cf Flood Elev= 148.40' Surf.Area= 3,301 sf Storage= 1,481 cf Plug-Flow detention time= 1.6 min calculated for 0.014 af (100% of inflow) Center-of-Mass det. time= 1.1 min ( 817.7 - 816.6 ) Volume Invert Avail.Storage Storage Description #1 147.50' 1,440 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,481 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 1,764 441 441 148.40 3,233 999 1,440 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 19.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.09' S= 0.0216 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 19HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.00 cfs @ 12.10 hrs HW=146.40' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.20 cfs @ 12.10 hrs HW=146.40' (Free Discharge) 3=Culvert (Passes 0.20 cfs of 4.48 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.20 cfs @ 2.34 fps) Summary for Pond 13P: RG13 Inflow Area = 0.079 ac, 73.59% Impervious, Inflow Depth > 1.26" for 1-Year event Inflow = 0.13 cfs @ 12.08 hrs, Volume= 0.008 af Outflow = 0.13 cfs @ 12.08 hrs, Volume= 0.008 af, Atten= 0%, Lag= 0.4 min Discarded = 0.00 cfs @ 12.08 hrs, Volume= 0.001 af Primary = 0.13 cfs @ 12.08 hrs, Volume= 0.007 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.26' @ 12.08 hrs Surf.Area= 36 sf Storage= 4 cf Flood Elev= 148.70' Surf.Area= 1,047 sf Storage= 282 cf Plug-Flow detention time= 1.2 min calculated for 0.008 af (100% of inflow) Center-of-Mass det. time= 0.8 min ( 790.5 - 789.7 ) Volume Invert Avail.Storage Storage Description #1 147.50' 261 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 13 cf 3.21'W x 11.33'L x 1.21'H Field A 44 cf Overall - 10 cf Embedded = 33 cf x 40.0% Voids #3A 146.00' 8 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf Row Length Adjustment= -10.00' x 0.81 sf x 1 rows 282 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 127 32 32 148.40 249 75 107 148.50 269 26 133 148.70 1,011 128 261 Device Routing Invert Outlet Devices #1 Device 3 148.30'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.10'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 20HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 145.10' / 144.84' S= 0.0260 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.08 hrs HW=146.26' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.13 cfs @ 12.08 hrs HW=146.26' (Free Discharge) 3=Culvert (Passes 0.13 cfs of 3.08 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.13 cfs @ 1.74 fps) Summary for Pond 14P: RG14 Inflow Area = 0.050 ac, 59.73% Impervious, Inflow Depth > 0.95" for 1-Year event Inflow = 0.06 cfs @ 12.08 hrs, Volume= 0.004 af Outflow = 0.06 cfs @ 12.09 hrs, Volume= 0.004 af, Atten= 2%, Lag= 0.8 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.001 af Primary = 0.06 cfs @ 12.09 hrs, Volume= 0.003 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.16' @ 12.09 hrs Surf.Area= 68 sf Storage= 4 cf Flood Elev= 148.70' Surf.Area= 1,131 sf Storage= 357 cf Plug-Flow detention time= 2.3 min calculated for 0.004 af (100% of inflow) Center-of-Mass det. time= 1.8 min ( 807.1 - 805.3 ) Volume Invert Avail.Storage Storage Description #1 148.00' 316 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 357 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 0 0 0 148.30 331 50 50 148.40 450 39 89 148.70 1,063 227 316 Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.26'12.0" Round Culvert Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 21HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.10' / 145.26' S= -0.0160 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=146.16' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.06 cfs @ 12.09 hrs HW=146.16' (Free Discharge) 3=Culvert (Passes 0.06 cfs of 2.13 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.06 cfs @ 1.37 fps) Summary for Pond 15P: RG15 Inflow Area = 0.065 ac, 51.91% Impervious, Inflow Depth > 0.79" for 1-Year event Inflow = 0.07 cfs @ 12.08 hrs, Volume= 0.004 af Outflow = 0.06 cfs @ 12.09 hrs, Volume= 0.004 af, Atten= 2%, Lag= 0.8 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.001 af Primary = 0.06 cfs @ 12.09 hrs, Volume= 0.003 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.17' @ 12.09 hrs Surf.Area= 68 sf Storage= 4 cf Flood Elev= 148.70' Surf.Area= 880 sf Storage= 337 cf Plug-Flow detention time= 2.2 min calculated for 0.004 af (100% of inflow) Center-of-Mass det. time= 1.8 min ( 815.6 - 813.8 ) Volume Invert Avail.Storage Storage Description #1 147.80' 296 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 337 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.80 0 0 0 148.00 173 17 17 148.30 300 71 88 148.40 354 33 121 148.70 812 175 296 Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 22HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.20'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.20' / 144.84' S= 0.0360 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=146.17' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.06 cfs @ 12.09 hrs HW=146.17' (Free Discharge) 3=Culvert (Passes 0.06 cfs of 2.61 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.06 cfs @ 1.40 fps) Summary for Pond 16P: INF-10+11 Inflow Area = 0.368 ac, 90.56% Impervious, Inflow Depth > 1.81" for 1-Year event Inflow = 0.82 cfs @ 12.07 hrs, Volume= 0.055 af Outflow = 0.96 cfs @ 12.06 hrs, Volume= 0.049 af, Atten= 0%, Lag= 0.0 min Discarded = 0.03 cfs @ 12.06 hrs, Volume= 0.028 af Primary = 0.92 cfs @ 12.06 hrs, Volume= 0.020 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.23' @ 12.06 hrs Surf.Area= 909 sf Storage= 493 cf Flood Elev= 149.00' Surf.Area= 11,205 sf Storage= 3,082 cf Plug-Flow detention time= 84.7 min calculated for 0.049 af (88% of inflow) Center-of-Mass det. time= 47.3 min ( 805.4 - 758.1 ) Volume Invert Avail.Storage Storage Description #1 146.00' 271 cf Stone Bedding (Prismatic) Listed below (Recalc) 897 cf Overall - 219 cf Embedded = 678 cf x 40.0% Voids #2 146.08' 219 cf 10.0" Round Pipe Storage Inside #1 L= 402.0' #3 147.00' 2,592 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,082 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 897 0 0 147.00 897 897 897 Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 23HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 5,154 1,290 1,296 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.70'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.44' S= 0.0081 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.80'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0194 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.03 cfs @ 12.06 hrs HW=147.23' (Free Discharge) 5=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=0.90 cfs @ 12.06 hrs HW=147.23' (Free Discharge) 2=Culvert (Passes 0.45 cfs of 5.39 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.45 cfs @ 1.18 fps) 4=Culvert (Passes 0.45 cfs of 5.25 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.45 cfs @ 1.18 fps) Summary for Pond 17P: INF-6+8 Inflow Area = 0.293 ac, 88.50% Impervious, Inflow Depth > 1.69" for 1-Year event Inflow = 0.62 cfs @ 12.07 hrs, Volume= 0.041 af Outflow = 0.62 cfs @ 12.08 hrs, Volume= 0.037 af, Atten= 1%, Lag= 0.8 min Discarded = 0.02 cfs @ 12.08 hrs, Volume= 0.018 af Primary = 0.59 cfs @ 12.08 hrs, Volume= 0.019 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.96' @ 12.08 hrs Surf.Area= 616 sf Storage= 323 cf Flood Elev= 148.90' Surf.Area= 14,038 sf Storage= 3,704 cf Plug-Flow detention time= 68.4 min calculated for 0.037 af (90% of inflow) Center-of-Mass det. time= 36.3 min ( 802.9 - 766.6 ) Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 24HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Volume Invert Avail.Storage Storage Description #1 146.00' 188 cf Stone Bedding (Prismatic) Listed below (Recalc) 616 cf Overall - 146 cf Embedded = 470 cf x 40.0% Voids #2 146.08' 146 cf 10.0" Round Pipe Storage Inside #1 L= 267.0' #3 147.00' 3,371 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,704 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 616 0 0 147.00 616 616 616 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 6,711 1,679 1,685 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.80'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.32' S= 0.0155 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.50'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.15' S= 0.0113 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.02 cfs @ 12.08 hrs HW=146.95' (Free Discharge) 5=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=0.59 cfs @ 12.08 hrs HW=146.95' (Free Discharge) 2=Culvert (Passes 0.00 cfs of 4.86 cfs potential flow) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 4=Culvert (Passes 0.59 cfs of 5.29 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.59 cfs @ 1.29 fps) Summary for Pond 18P: INF-5+7 Inflow Area = 0.214 ac, 91.42% Impervious, Inflow Depth > 1.82" for 1-Year event Inflow = 0.48 cfs @ 12.07 hrs, Volume= 0.032 af Outflow = 0.78 cfs @ 12.08 hrs, Volume= 0.029 af, Atten= 0%, Lag= 0.5 min Discarded = 0.03 cfs @ 12.08 hrs, Volume= 0.021 af Primary = 0.75 cfs @ 12.08 hrs, Volume= 0.008 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 1-Year Rainfall=2.46"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 25HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev= 146.96' @ 12.08 hrs Surf.Area= 664 sf Storage= 357 cf Flood Elev= 148.90' Surf.Area= 5,822 sf Storage= 1,665 cf Plug-Flow detention time= 99.2 min calculated for 0.029 af (90% of inflow) Center-of-Mass det. time= 66.3 min ( 824.7 - 758.4 ) Volume Invert Avail.Storage Storage Description #1 145.60' 199 cf Stone Bedding (Prismatic) Listed below (Recalc) 652 cf Overall - 154 cf Embedded = 498 cf x 40.0% Voids #2 145.68' 154 cf 10.0" Round Pipe Storage Inside #1 L= 282.0' #3 146.60' 1,312 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 1,665 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 145.60 652 0 0 146.60 652 652 652 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.60 6 0 0 148.00 6 8 8 148.50 2,585 648 656 Device Routing Invert Outlet Devices #1 Device 2 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.60'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.60' / 144.32' S= 0.0097 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.90'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.70'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.15' S= 0.0190 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 145.60'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.03 cfs @ 12.08 hrs HW=146.96' (Free Discharge) 5=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=0.71 cfs @ 12.08 hrs HW=146.95' (Free Discharge) 2=Culvert (Passes 0.58 cfs of 5.15 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.58 cfs @ 1.28 fps) 4=Culvert (Passes 0.12 cfs of 5.01 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.12 cfs @ 0.76 fps) Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 26HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Time span=1.00-20.00 hrs, dt=0.01 hrs, 1901 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Runoff Area=8,350 sf 98.42% Impervious Runoff Depth>2.59"Subcatchment 1S: A1 Tc=5.0 min CN=97 Runoff=0.58 cfs 0.041 af Runoff Area=4,496 sf 92.70% Impervious Runoff Depth>2.39"Subcatchment 2S: A2 Tc=5.0 min CN=95 Runoff=0.30 cfs 0.021 af Runoff Area=6,870 sf 97.82% Impervious Runoff Depth>2.59"Subcatchment 3S: A3 Tc=5.0 min CN=97 Runoff=0.48 cfs 0.034 af Runoff Area=8,648 sf 82.34% Impervious Runoff Depth>2.01"Subcatchment 4S: A4 Tc=5.0 min CN=91 Runoff=0.51 cfs 0.033 af Runoff Area=25,964 sf 100.00% Impervious Runoff Depth>2.70"Subcatchment 5S: B2 Tc=5.0 min CN=98 Runoff=1.84 cfs 0.134 af Runoff Area=7,072 sf 0.00% Impervious Runoff Depth>0.34"Subcatchment 6S: POND Tc=0.0 min CN=61 Runoff=0.05 cfs 0.005 af Runoff Area=57,882 sf 0.00% Impervious Runoff Depth>2.01"Subcatchment 7S: PRE REAR Tc=5.0 min CN=91 Runoff=3.40 cfs 0.223 af Runoff Area=5,095 sf 91.89% Impervious Runoff Depth>2.39"Subcatchment 8S: A5 Tc=5.0 min CN=95 Runoff=0.34 cfs 0.023 af Runoff Area=6,947 sf 89.75% Impervious Runoff Depth>2.29"Subcatchment 9S: A6 Tc=5.0 min CN=94 Runoff=0.45 cfs 0.030 af Runoff Area=4,230 sf 90.85% Impervious Runoff Depth>2.39"Subcatchment 10S: A7 Tc=5.0 min CN=95 Runoff=0.28 cfs 0.019 af Runoff Area=5,823 sf 87.02% Impervious Runoff Depth>2.19"Subcatchment 11S: A8 Tc=5.0 min CN=93 Runoff=0.37 cfs 0.024 af Runoff Area=11,231 sf 77.08% Impervious Runoff Depth>1.92"Subcatchment 12S: A9 Tc=5.0 min CN=90 Runoff=0.64 cfs 0.041 af Runoff Area=9,635 sf 93.98% Impervious Runoff Depth>2.49"Subcatchment 13S: A10 Tc=5.0 min CN=96 Runoff=0.66 cfs 0.046 af Runoff Area=6,395 sf 85.41% Impervious Runoff Depth>2.19"Subcatchment 14S: A11 Tc=5.0 min CN=93 Runoff=0.40 cfs 0.027 af Runoff Area=9,957 sf 48.28% Impervious Runoff Depth>1.14"Subcatchment 15S: A12 Tc=5.0 min CN=79 Runoff=0.34 cfs 0.022 af Runoff Area=3,453 sf 73.59% Impervious Runoff Depth>1.76"Subcatchment 16S: A13 Tc=5.0 min CN=88 Runoff=0.18 cfs 0.012 af Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 27HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Runoff Area=2,168 sf 59.73% Impervious Runoff Depth>1.39"Subcatchment 17S: A14 Tc=5.0 min CN=83 Runoff=0.09 cfs 0.006 af Runoff Area=2,826 sf 51.91% Impervious Runoff Depth>1.20"Subcatchment 18S: A15 Tc=5.0 min CN=80 Runoff=0.10 cfs 0.006 af Runoff Area=6,971 sf 100.00% Impervious Runoff Depth>2.70"Subcatchment 19S: B1 Tc=5.0 min CN=98 Runoff=0.49 cfs 0.036 af Runoff Area=71,761 sf 44.08% Impervious Runoff Depth>1.84"Subcatchment 20S: PRE FRONT Tc=5.0 min CN=89 Runoff=3.91 cfs 0.253 af Peak Elev=145.23' Inflow=0.58 cfs 0.041 afPond 1C: CB1 12.0" Round Culvert n=0.012 L=124.0' S=0.0050 '/' Outflow=0.58 cfs 0.041 af Peak Elev=144.88' Inflow=2.72 cfs 0.196 afPond 1D: DMH1 18.0" Round Culvert n=0.012 L=58.0' S=0.0050 '/' Outflow=2.72 cfs 0.196 af Peak Elev=146.24' Storage=8,102 cf Inflow=3.75 cfs 0.268 afPond 1P: POST REAR Discarded=0.11 cfs 0.095 af Primary=0.00 cfs 0.000 af Outflow=0.11 cfs 0.095 af Peak Elev=145.27' Inflow=0.30 cfs 0.021 afPond 2C: CB2 12.0" Round Culvert n=0.012 L=8.0' S=0.0437 '/' Outflow=0.30 cfs 0.021 af Peak Elev=144.61' Inflow=3.20 cfs 0.230 afPond 2D: DMH2 18.0" Round Culvert n=0.012 L=50.0' S=0.0050 '/' Outflow=3.20 cfs 0.230 af Peak Elev=145.33' Storage=4,679 cf Inflow=4.10 cfs 0.196 afPond 2P: POST FRONT Outflow=1.61 cfs 0.163 af Peak Elev=145.17' Inflow=0.48 cfs 0.034 afPond 3C: CB3 12.0" Round Culvert n=0.012 L=13.0' S=0.0115 '/' Outflow=0.48 cfs 0.034 af Peak Elev=144.35' Inflow=3.71 cfs 0.264 afPond 3D: DMH3 18.0" Round Culvert n=0.012 L=54.0' S=0.0056 '/' Outflow=3.71 cfs 0.264 af Peak Elev=145.17' Inflow=0.51 cfs 0.033 afPond 4C: CB4 12.0" Round Culvert n=0.012 L=8.0' S=0.0188 '/' Outflow=0.51 cfs 0.033 af Peak Elev=147.42' Storage=55 cf Inflow=0.64 cfs 0.041 afPond 9P: RG9 Discarded=0.02 cfs 0.002 af Primary=0.54 cfs 0.039 af Outflow=0.56 cfs 0.041 af Peak Elev=146.72' Storage=25 cf Inflow=0.34 cfs 0.022 afPond 12P: RG12 Discarded=0.00 cfs 0.001 af Primary=0.31 cfs 0.020 af Outflow=0.32 cfs 0.022 af Peak Elev=146.35' Storage=6 cf Inflow=0.18 cfs 0.012 afPond 13P: RG13 Discarded=0.00 cfs 0.001 af Primary=0.18 cfs 0.011 af Outflow=0.18 cfs 0.012 af Peak Elev=146.21' Storage=6 cf Inflow=0.09 cfs 0.006 afPond 14P: RG14 Discarded=0.00 cfs 0.001 af Primary=0.09 cfs 0.004 af Outflow=0.09 cfs 0.006 af Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 28HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev=146.22' Storage=6 cf Inflow=0.10 cfs 0.006 afPond 15P: RG15 Discarded=0.00 cfs 0.001 af Primary=0.10 cfs 0.005 af Outflow=0.10 cfs 0.006 af Peak Elev=147.24' Storage=493 cf Inflow=1.06 cfs 0.073 afPond 16P: INF-10+11 Discarded=0.03 cfs 0.031 af Primary=1.03 cfs 0.034 af Outflow=1.06 cfs 0.065 af Peak Elev=146.99' Storage=331 cf Inflow=0.82 cfs 0.055 afPond 17P: INF-6+8 Discarded=0.02 cfs 0.020 af Primary=0.79 cfs 0.030 af Outflow=0.81 cfs 0.050 af Peak Elev=146.94' Storage=357 cf Inflow=0.62 cfs 0.043 afPond 18P: INF-5+7 Discarded=0.03 cfs 0.023 af Primary=0.62 cfs 0.016 af Outflow=0.65 cfs 0.038 af Total Runoff Area = 6.101 ac Runoff Volume = 1.037 af Average Runoff Depth = 2.04" 45.85% Pervious = 2.798 ac 54.15% Impervious = 3.304 ac Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 29HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: A1 Runoff = 0.58 cfs @ 12.07 hrs, Volume= 0.041 af, Depth> 2.59" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 8,218 98 Paved parking, HSG B 132 61 >75% Grass cover, Good, HSG B 8,350 97 Weighted Average 132 1.58% Pervious Area 8,218 98.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: A2 Runoff = 0.30 cfs @ 12.07 hrs, Volume= 0.021 af, Depth> 2.39" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 4,168 98 Paved parking, HSG B 328 61 >75% Grass cover, Good, HSG B 4,496 95 Weighted Average 328 7.30% Pervious Area 4,168 92.70% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 3S: A3 Runoff = 0.48 cfs @ 12.07 hrs, Volume= 0.034 af, Depth> 2.59" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 6,720 98 Paved parking, HSG B 150 61 >75% Grass cover, Good, HSG B 6,870 97 Weighted Average 150 2.18% Pervious Area 6,720 97.82% Impervious Area Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 30HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 4S: A4 Runoff = 0.51 cfs @ 12.07 hrs, Volume= 0.033 af, Depth> 2.01" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 7,121 98 Paved parking, HSG B 1,527 61 >75% Grass cover, Good, HSG B 8,648 91 Weighted Average 1,527 17.66% Pervious Area 7,121 82.34% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: B2 Runoff = 1.84 cfs @ 12.07 hrs, Volume= 0.134 af, Depth> 2.70" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 25,964 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 25,964 98 Weighted Average 25,964 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 6S: POND Runoff = 0.05 cfs @ 12.03 hrs, Volume= 0.005 af, Depth> 0.34" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 31HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 7,072 61 >75% Grass cover, Good, HSG B 7,072 100.00% Pervious Area Summary for Subcatchment 7S: PRE REAR Runoff = 3.40 cfs @ 12.07 hrs, Volume= 0.223 af, Depth> 2.01" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 9,064 67 Brush, Poor, HSG B 48,818 96 Gravel surface, HSG B 57,882 91 Weighted Average 57,882 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 8S: A5 Runoff = 0.34 cfs @ 12.07 hrs, Volume= 0.023 af, Depth> 2.39" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 4,682 98 Paved parking, HSG B 413 61 >75% Grass cover, Good, HSG B 5,095 95 Weighted Average 413 8.11% Pervious Area 4,682 91.89% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: A6 Runoff = 0.45 cfs @ 12.07 hrs, Volume= 0.030 af, Depth> 2.29" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 32HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 6,235 98 Paved parking, HSG B 712 61 >75% Grass cover, Good, HSG B 6,947 94 Weighted Average 712 10.25% Pervious Area 6,235 89.75% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 10S: A7 Runoff = 0.28 cfs @ 12.07 hrs, Volume= 0.019 af, Depth> 2.39" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 3,843 98 Paved parking, HSG B 387 61 >75% Grass cover, Good, HSG B 4,230 95 Weighted Average 387 9.15% Pervious Area 3,843 90.85% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 11S: A8 Runoff = 0.37 cfs @ 12.07 hrs, Volume= 0.024 af, Depth> 2.19" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 5,067 98 Paved parking, HSG B 756 61 >75% Grass cover, Good, HSG B 5,823 93 Weighted Average 756 12.98% Pervious Area 5,067 87.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 33HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 12S: A9 Runoff = 0.64 cfs @ 12.07 hrs, Volume= 0.041 af, Depth> 1.92" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 8,657 98 Paved parking, HSG B 2,574 61 >75% Grass cover, Good, HSG B 11,231 90 Weighted Average 2,574 22.92% Pervious Area 8,657 77.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 13S: A10 Runoff = 0.66 cfs @ 12.07 hrs, Volume= 0.046 af, Depth> 2.49" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 9,055 98 Paved parking, HSG B 580 61 >75% Grass cover, Good, HSG B 9,635 96 Weighted Average 580 6.02% Pervious Area 9,055 93.98% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 14S: A11 Runoff = 0.40 cfs @ 12.07 hrs, Volume= 0.027 af, Depth> 2.19" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 5,462 98 Paved parking, HSG B 933 61 >75% Grass cover, Good, HSG B 6,395 93 Weighted Average 933 14.59% Pervious Area 5,462 85.41% Impervious Area Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 34HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 15S: A12 Runoff = 0.34 cfs @ 12.08 hrs, Volume= 0.022 af, Depth> 1.14" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 4,807 98 Paved parking, HSG B 5,150 61 >75% Grass cover, Good, HSG B 9,957 79 Weighted Average 5,150 51.72% Pervious Area 4,807 48.28% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 16S: A13 Runoff = 0.18 cfs @ 12.07 hrs, Volume= 0.012 af, Depth> 1.76" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 2,541 98 Paved parking, HSG B 912 61 >75% Grass cover, Good, HSG B 3,453 88 Weighted Average 912 26.41% Pervious Area 2,541 73.59% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 17S: A14 Runoff = 0.09 cfs @ 12.08 hrs, Volume= 0.006 af, Depth> 1.39" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 35HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 1,295 98 Paved parking, HSG B 873 61 >75% Grass cover, Good, HSG B 2,168 83 Weighted Average 873 40.27% Pervious Area 1,295 59.73% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 18S: A15 Runoff = 0.10 cfs @ 12.08 hrs, Volume= 0.006 af, Depth> 1.20" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 1,467 98 Paved parking, HSG B 1,359 61 >75% Grass cover, Good, HSG B 2,826 80 Weighted Average 1,359 48.09% Pervious Area 1,467 51.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 19S: B1 Runoff = 0.49 cfs @ 12.07 hrs, Volume= 0.036 af, Depth> 2.70" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 6,971 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 6,971 98 Weighted Average 6,971 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 36HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 20S: PRE FRONT Runoff = 3.91 cfs @ 12.07 hrs, Volume= 0.253 af, Depth> 1.84" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07" Area (sf) CN Description 24,527 96 Gravel surface, HSG B 15,601 61 >75% Grass cover, Good, HSG B 31,633 98 Paved parking, HSG B 71,761 89 Weighted Average 40,128 55.92% Pervious Area 31,633 44.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Pond 1C: CB1 Inflow Area = 0.192 ac, 98.42% Impervious, Inflow Depth > 2.59" for 2-Year event Inflow = 0.58 cfs @ 12.07 hrs, Volume= 0.041 af Outflow = 0.58 cfs @ 12.07 hrs, Volume= 0.041 af, Atten= 0%, Lag= 0.0 min Primary = 0.58 cfs @ 12.07 hrs, Volume= 0.041 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.23' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 124.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.58 cfs @ 12.07 hrs HW=145.23' (Free Discharge) 1=Culvert (Barrel Controls 0.58 cfs @ 2.66 fps) Summary for Pond 1D: DMH1 Inflow Area = 0.891 ac, 98.81% Impervious, Inflow Depth > 2.64" for 2-Year event Inflow = 2.72 cfs @ 12.07 hrs, Volume= 0.196 af Outflow = 2.72 cfs @ 12.07 hrs, Volume= 0.196 af, Atten= 0%, Lag= 0.0 min Primary = 2.72 cfs @ 12.07 hrs, Volume= 0.196 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 144.88' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.00'18.0" Round 18" CPEP Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 37HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 58.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.00' / 143.71' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=2.72 cfs @ 12.07 hrs HW=144.88' (Free Discharge) 1=18" CPEP (Barrel Controls 2.72 cfs @ 3.62 fps) Summary for Pond 1P: POST REAR Inflow Area = 1.410 ac, 85.00% Impervious, Inflow Depth > 2.28" for 2-Year event Inflow = 3.75 cfs @ 12.07 hrs, Volume= 0.268 af Outflow = 0.11 cfs @ 15.89 hrs, Volume= 0.095 af, Atten= 97%, Lag= 229.1 min Discarded = 0.11 cfs @ 15.89 hrs, Volume= 0.095 af Primary = 0.00 cfs @ 1.00 hrs, Volume= 0.000 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.24' @ 15.89 hrs Surf.Area= 3,851 sf Storage= 8,102 cf Plug-Flow detention time= 238.4 min calculated for 0.095 af (35% of inflow) Center-of-Mass det. time= 108.4 min ( 848.9 - 740.5 ) Volume Invert Avail.Storage Storage Description #1 143.00' 11,310 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 143.00 1,320 0 0 144.00 1,986 1,653 1,653 145.00 2,752 2,369 4,022 146.00 3,619 3,186 7,208 147.00 4,586 4,103 11,310 Device Routing Invert Outlet Devices #1 Discarded 143.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 135.00' #2 Primary 146.50'12.0' long x 16.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Discarded OutFlow Max=0.11 cfs @ 15.89 hrs HW=146.24' (Free Discharge) 1=Exfiltration ( Controls 0.11 cfs) Primary OutFlow Max=0.00 cfs @ 1.00 hrs HW=143.00' (Free Discharge) 2=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 38HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 2C: CB2 Inflow Area = 0.103 ac, 92.70% Impervious, Inflow Depth > 2.39" for 2-Year event Inflow = 0.30 cfs @ 12.07 hrs, Volume= 0.021 af Outflow = 0.30 cfs @ 12.07 hrs, Volume= 0.021 af, Atten= 0%, Lag= 0.0 min Primary = 0.30 cfs @ 12.07 hrs, Volume= 0.021 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.27' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 145.00'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.00' / 144.65' S= 0.0437 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.30 cfs @ 12.07 hrs HW=145.27' (Free Discharge) 1=Culvert (Inlet Controls 0.30 cfs @ 1.76 fps) Summary for Pond 2D: DMH2 Inflow Area = 1.049 ac, 98.66% Impervious, Inflow Depth > 2.64" for 2-Year event Inflow = 3.20 cfs @ 12.07 hrs, Volume= 0.230 af Outflow = 3.20 cfs @ 12.07 hrs, Volume= 0.230 af, Atten= 0%, Lag= 0.0 min Primary = 3.20 cfs @ 12.07 hrs, Volume= 0.230 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 144.61' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.63'18.0" Round 18" CPEP L= 50.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.63' / 143.38' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=3.20 cfs @ 12.07 hrs HW=144.61' (Free Discharge) 1=18" CPEP (Barrel Controls 3.20 cfs @ 3.72 fps) Summary for Pond 2P: POST FRONT Inflow Area = 1.716 ac, 80.40% Impervious, Inflow Depth > 1.37" for 2-Year event Inflow = 4.10 cfs @ 12.07 hrs, Volume= 0.196 af Outflow = 1.61 cfs @ 12.30 hrs, Volume= 0.163 af, Atten= 61%, Lag= 13.7 min Primary = 1.61 cfs @ 12.30 hrs, Volume= 0.163 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Starting Elev= 144.27' Surf.Area= 2,195 sf Storage= 940 cf Peak Elev= 145.33' @ 12.30 hrs Surf.Area= 3,806 sf Storage= 4,679 cf (3,738 cf above start) Flood Elev= 148.20' Surf.Area= 508 sf Storage= 8,258 cf (7,318 cf above start) Plug-Flow detention time= 111.6 min calculated for 0.142 af (72% of inflow) Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 39HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Center-of-Mass det. time= 53.6 min ( 811.4 - 757.7 ) Volume Invert Avail.Storage Storage Description #1 143.90' 509 cf 4.00'D x 4.50'H DMH x 9 #2 143.86' 226 cf 30.0" Round 30" Flat CPEP (10-11) L= 46.0' S= 0.0070 '/' #3 143.74' 324 cf 30.0" Round 30" Flat CPEP (11-12) L= 66.0' S= 0.0003 '/' #4 143.78' 275 cf 30.0" Round 30" Flat CPEP (12-Out) L= 56.0' S= 0.0016 '/' #5 143.88' 1,924 cf 30.0" Round 30" Flat CPEP (9-Out) x 4 L= 98.0' S= 0.0030 '/' #6 143.39' 1,031 cf 30.0" Round 30" Flat CPEP (6-9) x 3 L= 70.0' S= 0.0007 '/' #7 143.59' 260 cf 30.0" Round 30" Flat CPEP (8-9) L= 53.0' S= 0.0008 '/' #8 143.38' 476 cf 30.0" Round 30" Flat CPEP (7-8) L= 97.0' S= 0.0008 '/' #9 143.39' 285 cf 30.0" Round 30" Flat CPEP (5-6) L= 58.0' S= 0.0007 '/' #10 143.50' 422 cf 30.0" Round 30" Flat CPEP (4-5) L= 86.0' S= 0.0003 '/' #11 148.00' 333 cf Custom Stage Data (Prismatic) Listed below (Recalc) #12 144.27' 2,376 cf 30.0" Round Prop. 30" Flat CPEP L= 484.0' #13 144.27' 113 cf 4.00'D x 4.50'H Prop. DMH x 2 8,554 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 370 0 0 148.90 370 333 333 Device Routing Invert Outlet Devices #1 Device 3 144.27'10.0" Vert. 10" Orifice C= 0.600 #2 Device 3 146.85'36.0" W x 4.0" H Vert. 4"x36" Weir/Orifice C= 0.600 #3 Primary 144.65'12.0" Round 12" Culvert L= 16.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.65' / 143.50' S= 0.0719 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Primary 148.00'37.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=1.61 cfs @ 12.30 hrs HW=145.33' (Free Discharge) 3=12" Culvert (Inlet Controls 1.61 cfs @ 2.82 fps) 1=10" Orifice (Passes 1.61 cfs of 2.11 cfs potential flow) 2=4"x36" Weir/Orifice ( Controls 0.00 cfs) 4=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 40HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 3C: CB3 Inflow Area = 0.158 ac, 97.82% Impervious, Inflow Depth > 2.59" for 2-Year event Inflow = 0.48 cfs @ 12.07 hrs, Volume= 0.034 af Outflow = 0.48 cfs @ 12.07 hrs, Volume= 0.034 af, Atten= 0%, Lag= 0.0 min Primary = 0.48 cfs @ 12.07 hrs, Volume= 0.034 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.17' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 13.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0115 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.48 cfs @ 12.07 hrs HW=145.17' (Free Discharge) 1=Culvert (Barrel Controls 0.48 cfs @ 2.70 fps) Summary for Pond 3D: DMH3 Inflow Area = 1.247 ac, 96.07% Impervious, Inflow Depth > 2.54" for 2-Year event Inflow = 3.71 cfs @ 12.07 hrs, Volume= 0.264 af Outflow = 3.71 cfs @ 12.07 hrs, Volume= 0.264 af, Atten= 0%, Lag= 0.0 min Primary = 3.71 cfs @ 12.07 hrs, Volume= 0.264 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 144.35' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.30'18.0" Round Culvert L= 54.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.30' / 143.00' S= 0.0056 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=3.70 cfs @ 12.07 hrs HW=144.35' (Free Discharge) 1=Culvert (Barrel Controls 3.70 cfs @ 3.96 fps) Summary for Pond 4C: CB4 Inflow Area = 0.199 ac, 82.34% Impervious, Inflow Depth > 2.01" for 2-Year event Inflow = 0.51 cfs @ 12.07 hrs, Volume= 0.033 af Outflow = 0.51 cfs @ 12.07 hrs, Volume= 0.033 af, Atten= 0%, Lag= 0.0 min Primary = 0.51 cfs @ 12.07 hrs, Volume= 0.033 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.17' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 41HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0188 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.51 cfs @ 12.07 hrs HW=145.17' (Free Discharge) 1=Culvert (Barrel Controls 0.51 cfs @ 2.87 fps) Summary for Pond 9P: RG9 Inflow Area = 0.258 ac, 77.08% Impervious, Inflow Depth > 1.92" for 2-Year event Inflow = 0.64 cfs @ 12.07 hrs, Volume= 0.041 af Outflow = 0.56 cfs @ 12.11 hrs, Volume= 0.041 af, Atten= 12%, Lag= 2.5 min Discarded = 0.02 cfs @ 12.11 hrs, Volume= 0.002 af Primary = 0.54 cfs @ 12.11 hrs, Volume= 0.039 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.42' @ 12.11 hrs Surf.Area= 709 sf Storage= 55 cf Flood Elev= 148.40' Surf.Area= 1,804 sf Storage= 1,004 cf Plug-Flow detention time= 1.4 min calculated for 0.041 af (100% of inflow) Center-of-Mass det. time= 1.1 min ( 776.1 - 775.0 ) Volume Invert Avail.Storage Storage Description #1 147.40' 963 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 145.60' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 145.60' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,004 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.40 632 0 0 148.00 853 445 445 148.40 1,736 518 963 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 145.60'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 34.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 143.94' S= 0.0165 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 145.60'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 42HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.02 cfs @ 12.11 hrs HW=147.42' (Free Discharge) 2=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=0.54 cfs @ 12.11 hrs HW=147.42' (Free Discharge) 3=Culvert (Passes 0.54 cfs of 5.89 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.54 cfs @ 6.20 fps) Summary for Pond 12P: RG12 Inflow Area = 0.229 ac, 48.28% Impervious, Inflow Depth > 1.14" for 2-Year event Inflow = 0.34 cfs @ 12.08 hrs, Volume= 0.022 af Outflow = 0.32 cfs @ 12.11 hrs, Volume= 0.022 af, Atten= 7%, Lag= 1.8 min Discarded = 0.00 cfs @ 12.11 hrs, Volume= 0.001 af Primary = 0.31 cfs @ 12.11 hrs, Volume= 0.020 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.72' @ 12.11 hrs Surf.Area= 68 sf Storage= 25 cf Flood Elev= 148.40' Surf.Area= 3,301 sf Storage= 1,481 cf Plug-Flow detention time= 1.5 min calculated for 0.022 af (100% of inflow) Center-of-Mass det. time= 1.0 min ( 807.9 - 806.9 ) Volume Invert Avail.Storage Storage Description #1 147.50' 1,440 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,481 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 1,764 441 441 148.40 3,233 999 1,440 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 19.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.09' S= 0.0216 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 43HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.00 cfs @ 12.11 hrs HW=146.72' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.31 cfs @ 12.11 hrs HW=146.72' (Free Discharge) 3=Culvert (Passes 0.31 cfs of 4.96 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.31 cfs @ 3.59 fps) Summary for Pond 13P: RG13 Inflow Area = 0.079 ac, 73.59% Impervious, Inflow Depth > 1.76" for 2-Year event Inflow = 0.18 cfs @ 12.07 hrs, Volume= 0.012 af Outflow = 0.18 cfs @ 12.08 hrs, Volume= 0.012 af, Atten= 1%, Lag= 0.7 min Discarded = 0.00 cfs @ 12.08 hrs, Volume= 0.001 af Primary = 0.18 cfs @ 12.08 hrs, Volume= 0.011 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.35' @ 12.08 hrs Surf.Area= 36 sf Storage= 6 cf Flood Elev= 148.70' Surf.Area= 1,047 sf Storage= 282 cf Plug-Flow detention time= 1.0 min calculated for 0.012 af (100% of inflow) Center-of-Mass det. time= 0.7 min ( 782.6 - 781.9 ) Volume Invert Avail.Storage Storage Description #1 147.50' 261 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 13 cf 3.21'W x 11.33'L x 1.21'H Field A 44 cf Overall - 10 cf Embedded = 33 cf x 40.0% Voids #3A 146.00' 8 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf Row Length Adjustment= -10.00' x 0.81 sf x 1 rows 282 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 127 32 32 148.40 249 75 107 148.50 269 26 133 148.70 1,011 128 261 Device Routing Invert Outlet Devices #1 Device 3 148.30'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.10'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 44HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 145.10' / 144.84' S= 0.0260 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.08 hrs HW=146.35' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.18 cfs @ 12.08 hrs HW=146.35' (Free Discharge) 3=Culvert (Passes 0.18 cfs of 3.26 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.18 cfs @ 2.03 fps) Summary for Pond 14P: RG14 Inflow Area = 0.050 ac, 59.73% Impervious, Inflow Depth > 1.39" for 2-Year event Inflow = 0.09 cfs @ 12.08 hrs, Volume= 0.006 af Outflow = 0.09 cfs @ 12.09 hrs, Volume= 0.006 af, Atten= 1%, Lag= 0.8 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.001 af Primary = 0.09 cfs @ 12.09 hrs, Volume= 0.004 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.21' @ 12.09 hrs Surf.Area= 68 sf Storage= 6 cf Flood Elev= 148.70' Surf.Area= 1,131 sf Storage= 357 cf Plug-Flow detention time= 2.1 min calculated for 0.006 af (100% of inflow) Center-of-Mass det. time= 1.7 min ( 798.3 - 796.6 ) Volume Invert Avail.Storage Storage Description #1 148.00' 316 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 357 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 0 0 0 148.30 331 50 50 148.40 450 39 89 148.70 1,063 227 316 Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.26'12.0" Round Culvert Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 45HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.10' / 145.26' S= -0.0160 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=146.21' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.09 cfs @ 12.09 hrs HW=146.21' (Free Discharge) 3=Culvert (Passes 0.09 cfs of 2.25 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.09 cfs @ 1.55 fps) Summary for Pond 15P: RG15 Inflow Area = 0.065 ac, 51.91% Impervious, Inflow Depth > 1.20" for 2-Year event Inflow = 0.10 cfs @ 12.08 hrs, Volume= 0.006 af Outflow = 0.10 cfs @ 12.09 hrs, Volume= 0.006 af, Atten= 1%, Lag= 0.8 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.001 af Primary = 0.10 cfs @ 12.09 hrs, Volume= 0.005 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.22' @ 12.09 hrs Surf.Area= 68 sf Storage= 6 cf Flood Elev= 148.70' Surf.Area= 880 sf Storage= 337 cf Plug-Flow detention time= 2.1 min calculated for 0.006 af (100% of inflow) Center-of-Mass det. time= 1.6 min ( 806.0 - 804.4 ) Volume Invert Avail.Storage Storage Description #1 147.80' 296 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 337 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.80 0 0 0 148.00 173 17 17 148.30 300 71 88 148.40 354 33 121 148.70 812 175 296 Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 46HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.20'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.20' / 144.84' S= 0.0360 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=146.22' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.10 cfs @ 12.09 hrs HW=146.22' (Free Discharge) 3=Culvert (Passes 0.10 cfs of 2.73 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.10 cfs @ 1.60 fps) Summary for Pond 16P: INF-10+11 Inflow Area = 0.368 ac, 90.56% Impervious, Inflow Depth > 2.37" for 2-Year event Inflow = 1.06 cfs @ 12.07 hrs, Volume= 0.073 af Outflow = 1.06 cfs @ 12.07 hrs, Volume= 0.065 af, Atten= 0%, Lag= 0.0 min Discarded = 0.03 cfs @ 12.07 hrs, Volume= 0.031 af Primary = 1.03 cfs @ 12.07 hrs, Volume= 0.034 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.24' @ 12.07 hrs Surf.Area= 909 sf Storage= 493 cf Flood Elev= 149.00' Surf.Area= 11,205 sf Storage= 3,082 cf Plug-Flow detention time= 68.8 min calculated for 0.065 af (89% of inflow) Center-of-Mass det. time= 33.2 min ( 785.0 - 751.8 ) Volume Invert Avail.Storage Storage Description #1 146.00' 271 cf Stone Bedding (Prismatic) Listed below (Recalc) 897 cf Overall - 219 cf Embedded = 678 cf x 40.0% Voids #2 146.08' 219 cf 10.0" Round Pipe Storage Inside #1 L= 402.0' #3 147.00' 2,592 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,082 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 897 0 0 147.00 897 897 897 Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 47HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 5,154 1,290 1,296 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.70'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.44' S= 0.0081 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.80'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0194 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.03 cfs @ 12.07 hrs HW=147.24' (Free Discharge) 5=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=1.02 cfs @ 12.07 hrs HW=147.24' (Free Discharge) 2=Culvert (Passes 0.51 cfs of 5.40 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.51 cfs @ 1.22 fps) 4=Culvert (Passes 0.51 cfs of 5.27 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.51 cfs @ 1.22 fps) Summary for Pond 17P: INF-6+8 Inflow Area = 0.293 ac, 88.50% Impervious, Inflow Depth > 2.24" for 2-Year event Inflow = 0.82 cfs @ 12.07 hrs, Volume= 0.055 af Outflow = 0.81 cfs @ 12.08 hrs, Volume= 0.050 af, Atten= 1%, Lag= 0.7 min Discarded = 0.02 cfs @ 12.08 hrs, Volume= 0.020 af Primary = 0.79 cfs @ 12.08 hrs, Volume= 0.030 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.99' @ 12.08 hrs Surf.Area= 616 sf Storage= 331 cf Flood Elev= 148.90' Surf.Area= 14,038 sf Storage= 3,704 cf Plug-Flow detention time= 55.5 min calculated for 0.050 af (91% of inflow) Center-of-Mass det. time= 24.9 min ( 784.7 - 759.8 ) Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 48HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Volume Invert Avail.Storage Storage Description #1 146.00' 188 cf Stone Bedding (Prismatic) Listed below (Recalc) 616 cf Overall - 146 cf Embedded = 470 cf x 40.0% Voids #2 146.08' 146 cf 10.0" Round Pipe Storage Inside #1 L= 267.0' #3 147.00' 3,371 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,704 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 616 0 0 147.00 616 616 616 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 6,711 1,679 1,685 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.80'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.32' S= 0.0155 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.50'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.15' S= 0.0113 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.02 cfs @ 12.08 hrs HW=146.99' (Free Discharge) 5=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=0.78 cfs @ 12.08 hrs HW=146.99' (Free Discharge) 2=Culvert (Passes 0.00 cfs of 4.91 cfs potential flow) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 4=Culvert (Passes 0.78 cfs of 5.33 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.78 cfs @ 1.41 fps) Summary for Pond 18P: INF-5+7 Inflow Area = 0.214 ac, 91.42% Impervious, Inflow Depth > 2.39" for 2-Year event Inflow = 0.62 cfs @ 12.07 hrs, Volume= 0.043 af Outflow = 0.65 cfs @ 12.07 hrs, Volume= 0.038 af, Atten= 0%, Lag= 0.0 min Discarded = 0.03 cfs @ 12.07 hrs, Volume= 0.023 af Primary = 0.62 cfs @ 12.07 hrs, Volume= 0.016 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 2-Year Rainfall=3.07"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 49HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev= 146.94' @ 12.07 hrs Surf.Area= 664 sf Storage= 357 cf Flood Elev= 148.90' Surf.Area= 5,822 sf Storage= 1,665 cf Plug-Flow detention time= 81.1 min calculated for 0.038 af (90% of inflow) Center-of-Mass det. time= 47.8 min ( 799.7 - 751.9 ) Volume Invert Avail.Storage Storage Description #1 145.60' 199 cf Stone Bedding (Prismatic) Listed below (Recalc) 652 cf Overall - 154 cf Embedded = 498 cf x 40.0% Voids #2 145.68' 154 cf 10.0" Round Pipe Storage Inside #1 L= 282.0' #3 146.60' 1,312 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 1,665 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 145.60 652 0 0 146.60 652 652 652 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.60 6 0 0 148.00 6 8 8 148.50 2,585 648 656 Device Routing Invert Outlet Devices #1 Device 2 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.60'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.60' / 144.32' S= 0.0097 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.90'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.70'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.15' S= 0.0190 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 145.60'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.03 cfs @ 12.07 hrs HW=146.94' (Free Discharge) 5=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=0.62 cfs @ 12.07 hrs HW=146.94' (Free Discharge) 2=Culvert (Passes 0.53 cfs of 5.13 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.53 cfs @ 1.24 fps) 4=Culvert (Passes 0.09 cfs of 4.99 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.09 cfs @ 0.68 fps) Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 50HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Time span=1.00-20.00 hrs, dt=0.01 hrs, 1901 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Runoff Area=8,350 sf 98.42% Impervious Runoff Depth>3.55"Subcatchment 1S: A1 Tc=5.0 min CN=97 Runoff=0.78 cfs 0.057 af Runoff Area=4,496 sf 92.70% Impervious Runoff Depth>3.33"Subcatchment 2S: A2 Tc=5.0 min CN=95 Runoff=0.41 cfs 0.029 af Runoff Area=6,870 sf 97.82% Impervious Runoff Depth>3.55"Subcatchment 3S: A3 Tc=5.0 min CN=97 Runoff=0.64 cfs 0.047 af Runoff Area=8,648 sf 82.34% Impervious Runoff Depth>2.92"Subcatchment 4S: A4 Tc=5.0 min CN=91 Runoff=0.72 cfs 0.048 af Runoff Area=25,964 sf 100.00% Impervious Runoff Depth>3.67"Subcatchment 5S: B2 Tc=5.0 min CN=98 Runoff=2.46 cfs 0.182 af Runoff Area=7,072 sf 0.00% Impervious Runoff Depth>0.76"Subcatchment 6S: POND Tc=0.0 min CN=61 Runoff=0.16 cfs 0.010 af Runoff Area=57,882 sf 0.00% Impervious Runoff Depth>2.92"Subcatchment 7S: PRE REAR Tc=5.0 min CN=91 Runoff=4.85 cfs 0.324 af Runoff Area=5,095 sf 91.89% Impervious Runoff Depth>3.33"Subcatchment 8S: A5 Tc=5.0 min CN=95 Runoff=0.46 cfs 0.032 af Runoff Area=6,947 sf 89.75% Impervious Runoff Depth>3.23"Subcatchment 9S: A6 Tc=5.0 min CN=94 Runoff=0.62 cfs 0.043 af Runoff Area=4,230 sf 90.85% Impervious Runoff Depth>3.33"Subcatchment 10S: A7 Tc=5.0 min CN=95 Runoff=0.39 cfs 0.027 af Runoff Area=5,823 sf 87.02% Impervious Runoff Depth>3.12"Subcatchment 11S: A8 Tc=5.0 min CN=93 Runoff=0.51 cfs 0.035 af Runoff Area=11,231 sf 77.08% Impervious Runoff Depth>2.83"Subcatchment 12S: A9 Tc=5.0 min CN=90 Runoff=0.92 cfs 0.061 af Runoff Area=9,635 sf 93.98% Impervious Runoff Depth>3.44"Subcatchment 13S: A10 Tc=5.0 min CN=96 Runoff=0.89 cfs 0.063 af Runoff Area=6,395 sf 85.41% Impervious Runoff Depth>3.12"Subcatchment 14S: A11 Tc=5.0 min CN=93 Runoff=0.56 cfs 0.038 af Runoff Area=9,957 sf 48.28% Impervious Runoff Depth>1.88"Subcatchment 15S: A12 Tc=5.0 min CN=79 Runoff=0.56 cfs 0.036 af Runoff Area=3,453 sf 73.59% Impervious Runoff Depth>2.64"Subcatchment 16S: A13 Tc=5.0 min CN=88 Runoff=0.27 cfs 0.017 af Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 51HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Runoff Area=2,168 sf 59.73% Impervious Runoff Depth>2.20"Subcatchment 17S: A14 Tc=5.0 min CN=83 Runoff=0.14 cfs 0.009 af Runoff Area=2,826 sf 51.91% Impervious Runoff Depth>1.96"Subcatchment 18S: A15 Tc=5.0 min CN=80 Runoff=0.17 cfs 0.011 af Runoff Area=6,971 sf 100.00% Impervious Runoff Depth>3.67"Subcatchment 19S: B1 Tc=5.0 min CN=98 Runoff=0.66 cfs 0.049 af Runoff Area=71,761 sf 44.08% Impervious Runoff Depth>2.73"Subcatchment 20S: PRE FRONT Tc=5.0 min CN=89 Runoff=5.70 cfs 0.375 af Peak Elev=145.30' Inflow=0.78 cfs 0.057 afPond 1C: CB1 12.0" Round Culvert n=0.012 L=124.0' S=0.0050 '/' Outflow=0.78 cfs 0.057 af Peak Elev=145.05' Inflow=3.65 cfs 0.268 afPond 1D: DMH1 18.0" Round Culvert n=0.012 L=58.0' S=0.0050 '/' Outflow=3.65 cfs 0.268 af Peak Elev=146.58' Storage=9,468 cf Inflow=5.14 cfs 0.373 afPond 1P: POST REAR Discarded=0.12 cfs 0.108 af Primary=0.74 cfs 0.063 af Outflow=0.86 cfs 0.171 af Peak Elev=145.32' Inflow=0.41 cfs 0.029 afPond 2C: CB2 12.0" Round Culvert n=0.012 L=8.0' S=0.0437 '/' Outflow=0.41 cfs 0.029 af Peak Elev=144.80' Inflow=4.29 cfs 0.314 afPond 2D: DMH2 18.0" Round Culvert n=0.012 L=50.0' S=0.0050 '/' Outflow=4.29 cfs 0.314 af Peak Elev=145.71' Storage=6,027 cf Inflow=5.61 cfs 0.312 afPond 2P: POST FRONT Outflow=2.65 cfs 0.277 af Peak Elev=145.24' Inflow=0.64 cfs 0.047 afPond 3C: CB3 12.0" Round Culvert n=0.012 L=13.0' S=0.0115 '/' Outflow=0.64 cfs 0.047 af Peak Elev=144.57' Inflow=5.02 cfs 0.363 afPond 3D: DMH3 18.0" Round Culvert n=0.012 L=54.0' S=0.0056 '/' Outflow=5.02 cfs 0.363 af Peak Elev=145.25' Inflow=0.72 cfs 0.048 afPond 4C: CB4 12.0" Round Culvert n=0.012 L=8.0' S=0.0188 '/' Outflow=0.72 cfs 0.048 af Peak Elev=147.59' Storage=164 cf Inflow=0.92 cfs 0.061 afPond 9P: RG9 Discarded=0.02 cfs 0.003 af Primary=0.57 cfs 0.058 af Outflow=0.59 cfs 0.061 af Peak Elev=147.57' Storage=50 cf Inflow=0.56 cfs 0.036 afPond 12P: RG12 Discarded=0.01 cfs 0.002 af Primary=0.50 cfs 0.034 af Outflow=0.51 cfs 0.036 af Peak Elev=146.55' Storage=10 cf Inflow=0.27 cfs 0.017 afPond 13P: RG13 Discarded=0.00 cfs 0.001 af Primary=0.26 cfs 0.016 af Outflow=0.26 cfs 0.017 af Peak Elev=146.28' Storage=8 cf Inflow=0.14 cfs 0.009 afPond 14P: RG14 Discarded=0.00 cfs 0.001 af Primary=0.14 cfs 0.008 af Outflow=0.14 cfs 0.009 af Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 52HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev=146.31' Storage=9 cf Inflow=0.17 cfs 0.011 afPond 15P: RG15 Discarded=0.00 cfs 0.001 af Primary=0.16 cfs 0.009 af Outflow=0.16 cfs 0.011 af Peak Elev=147.27' Storage=494 cf Inflow=1.45 cfs 0.102 afPond 16P: INF-10+11 Discarded=0.03 cfs 0.034 af Primary=1.42 cfs 0.058 af Outflow=1.45 cfs 0.092 af Peak Elev=147.04' Storage=334 cf Inflow=1.13 cfs 0.078 afPond 17P: INF-6+8 Discarded=0.02 cfs 0.022 af Primary=1.14 cfs 0.050 af Outflow=1.16 cfs 0.072 af Peak Elev=146.97' Storage=357 cf Inflow=0.85 cfs 0.059 afPond 18P: INF-5+7 Discarded=0.03 cfs 0.025 af Primary=0.82 cfs 0.029 af Outflow=0.85 cfs 0.054 af Total Runoff Area = 6.101 ac Runoff Volume = 1.493 af Average Runoff Depth = 2.94" 45.85% Pervious = 2.798 ac 54.15% Impervious = 3.304 ac Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 53HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: A1 Runoff = 0.78 cfs @ 12.07 hrs, Volume= 0.057 af, Depth> 3.55" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 8,218 98 Paved parking, HSG B 132 61 >75% Grass cover, Good, HSG B 8,350 97 Weighted Average 132 1.58% Pervious Area 8,218 98.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: A2 Runoff = 0.41 cfs @ 12.07 hrs, Volume= 0.029 af, Depth> 3.33" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 4,168 98 Paved parking, HSG B 328 61 >75% Grass cover, Good, HSG B 4,496 95 Weighted Average 328 7.30% Pervious Area 4,168 92.70% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 3S: A3 Runoff = 0.64 cfs @ 12.07 hrs, Volume= 0.047 af, Depth> 3.55" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 6,720 98 Paved parking, HSG B 150 61 >75% Grass cover, Good, HSG B 6,870 97 Weighted Average 150 2.18% Pervious Area 6,720 97.82% Impervious Area Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 54HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 4S: A4 Runoff = 0.72 cfs @ 12.07 hrs, Volume= 0.048 af, Depth> 2.92" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 7,121 98 Paved parking, HSG B 1,527 61 >75% Grass cover, Good, HSG B 8,648 91 Weighted Average 1,527 17.66% Pervious Area 7,121 82.34% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: B2 Runoff = 2.46 cfs @ 12.07 hrs, Volume= 0.182 af, Depth> 3.67" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 25,964 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 25,964 98 Weighted Average 25,964 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 6S: POND Runoff = 0.16 cfs @ 12.01 hrs, Volume= 0.010 af, Depth> 0.76" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 55HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 7,072 61 >75% Grass cover, Good, HSG B 7,072 100.00% Pervious Area Summary for Subcatchment 7S: PRE REAR Runoff = 4.85 cfs @ 12.07 hrs, Volume= 0.324 af, Depth> 2.92" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 9,064 67 Brush, Poor, HSG B 48,818 96 Gravel surface, HSG B 57,882 91 Weighted Average 57,882 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 8S: A5 Runoff = 0.46 cfs @ 12.07 hrs, Volume= 0.032 af, Depth> 3.33" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 4,682 98 Paved parking, HSG B 413 61 >75% Grass cover, Good, HSG B 5,095 95 Weighted Average 413 8.11% Pervious Area 4,682 91.89% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: A6 Runoff = 0.62 cfs @ 12.07 hrs, Volume= 0.043 af, Depth> 3.23" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 56HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 6,235 98 Paved parking, HSG B 712 61 >75% Grass cover, Good, HSG B 6,947 94 Weighted Average 712 10.25% Pervious Area 6,235 89.75% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 10S: A7 Runoff = 0.39 cfs @ 12.07 hrs, Volume= 0.027 af, Depth> 3.33" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 3,843 98 Paved parking, HSG B 387 61 >75% Grass cover, Good, HSG B 4,230 95 Weighted Average 387 9.15% Pervious Area 3,843 90.85% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 11S: A8 Runoff = 0.51 cfs @ 12.07 hrs, Volume= 0.035 af, Depth> 3.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 5,067 98 Paved parking, HSG B 756 61 >75% Grass cover, Good, HSG B 5,823 93 Weighted Average 756 12.98% Pervious Area 5,067 87.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 57HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 12S: A9 Runoff = 0.92 cfs @ 12.07 hrs, Volume= 0.061 af, Depth> 2.83" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 8,657 98 Paved parking, HSG B 2,574 61 >75% Grass cover, Good, HSG B 11,231 90 Weighted Average 2,574 22.92% Pervious Area 8,657 77.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 13S: A10 Runoff = 0.89 cfs @ 12.07 hrs, Volume= 0.063 af, Depth> 3.44" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 9,055 98 Paved parking, HSG B 580 61 >75% Grass cover, Good, HSG B 9,635 96 Weighted Average 580 6.02% Pervious Area 9,055 93.98% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 14S: A11 Runoff = 0.56 cfs @ 12.07 hrs, Volume= 0.038 af, Depth> 3.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 5,462 98 Paved parking, HSG B 933 61 >75% Grass cover, Good, HSG B 6,395 93 Weighted Average 933 14.59% Pervious Area 5,462 85.41% Impervious Area Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 58HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 15S: A12 Runoff = 0.56 cfs @ 12.08 hrs, Volume= 0.036 af, Depth> 1.88" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 4,807 98 Paved parking, HSG B 5,150 61 >75% Grass cover, Good, HSG B 9,957 79 Weighted Average 5,150 51.72% Pervious Area 4,807 48.28% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 16S: A13 Runoff = 0.27 cfs @ 12.07 hrs, Volume= 0.017 af, Depth> 2.64" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 2,541 98 Paved parking, HSG B 912 61 >75% Grass cover, Good, HSG B 3,453 88 Weighted Average 912 26.41% Pervious Area 2,541 73.59% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 17S: A14 Runoff = 0.14 cfs @ 12.07 hrs, Volume= 0.009 af, Depth> 2.20" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 59HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 1,295 98 Paved parking, HSG B 873 61 >75% Grass cover, Good, HSG B 2,168 83 Weighted Average 873 40.27% Pervious Area 1,295 59.73% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 18S: A15 Runoff = 0.17 cfs @ 12.08 hrs, Volume= 0.011 af, Depth> 1.96" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 1,467 98 Paved parking, HSG B 1,359 61 >75% Grass cover, Good, HSG B 2,826 80 Weighted Average 1,359 48.09% Pervious Area 1,467 51.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 19S: B1 Runoff = 0.66 cfs @ 12.07 hrs, Volume= 0.049 af, Depth> 3.67" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 6,971 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 6,971 98 Weighted Average 6,971 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 60HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 20S: PRE FRONT Runoff = 5.70 cfs @ 12.07 hrs, Volume= 0.375 af, Depth> 2.73" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08" Area (sf) CN Description 24,527 96 Gravel surface, HSG B 15,601 61 >75% Grass cover, Good, HSG B 31,633 98 Paved parking, HSG B 71,761 89 Weighted Average 40,128 55.92% Pervious Area 31,633 44.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Pond 1C: CB1 Inflow Area = 0.192 ac, 98.42% Impervious, Inflow Depth > 3.55" for 5-Year event Inflow = 0.78 cfs @ 12.07 hrs, Volume= 0.057 af Outflow = 0.78 cfs @ 12.07 hrs, Volume= 0.057 af, Atten= 0%, Lag= 0.0 min Primary = 0.78 cfs @ 12.07 hrs, Volume= 0.057 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.30' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 124.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.78 cfs @ 12.07 hrs HW=145.30' (Free Discharge) 1=Culvert (Barrel Controls 0.78 cfs @ 2.88 fps) Summary for Pond 1D: DMH1 Inflow Area = 0.891 ac, 98.81% Impervious, Inflow Depth > 3.60" for 5-Year event Inflow = 3.65 cfs @ 12.07 hrs, Volume= 0.268 af Outflow = 3.65 cfs @ 12.07 hrs, Volume= 0.268 af, Atten= 0%, Lag= 0.0 min Primary = 3.65 cfs @ 12.07 hrs, Volume= 0.268 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.05' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.00'18.0" Round 18" CPEP Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 61HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 58.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.00' / 143.71' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=3.65 cfs @ 12.07 hrs HW=145.05' (Free Discharge) 1=18" CPEP (Barrel Controls 3.65 cfs @ 3.88 fps) Summary for Pond 1P: POST REAR Inflow Area = 1.410 ac, 85.00% Impervious, Inflow Depth > 3.17" for 5-Year event Inflow = 5.14 cfs @ 12.07 hrs, Volume= 0.373 af Outflow = 0.86 cfs @ 12.52 hrs, Volume= 0.171 af, Atten= 83%, Lag= 27.3 min Discarded = 0.12 cfs @ 12.52 hrs, Volume= 0.108 af Primary = 0.74 cfs @ 12.52 hrs, Volume= 0.063 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.58' @ 12.52 hrs Surf.Area= 4,180 sf Storage= 9,468 cf Plug-Flow detention time= 198.1 min calculated for 0.171 af (46% of inflow) Center-of-Mass det. time= 89.7 min ( 824.9 - 735.2 ) Volume Invert Avail.Storage Storage Description #1 143.00' 11,310 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 143.00 1,320 0 0 144.00 1,986 1,653 1,653 145.00 2,752 2,369 4,022 146.00 3,619 3,186 7,208 147.00 4,586 4,103 11,310 Device Routing Invert Outlet Devices #1 Discarded 143.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 135.00' #2 Primary 146.50'12.0' long x 16.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Discarded OutFlow Max=0.12 cfs @ 12.52 hrs HW=146.58' (Free Discharge) 1=Exfiltration ( Controls 0.12 cfs) Primary OutFlow Max=0.72 cfs @ 12.52 hrs HW=146.58' (Free Discharge) 2=Broad-Crested Rectangular Weir (Weir Controls 0.72 cfs @ 0.76 fps) Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 62HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 2C: CB2 Inflow Area = 0.103 ac, 92.70% Impervious, Inflow Depth > 3.33" for 5-Year event Inflow = 0.41 cfs @ 12.07 hrs, Volume= 0.029 af Outflow = 0.41 cfs @ 12.07 hrs, Volume= 0.029 af, Atten= 0%, Lag= 0.0 min Primary = 0.41 cfs @ 12.07 hrs, Volume= 0.029 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.32' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 145.00'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.00' / 144.65' S= 0.0437 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.41 cfs @ 12.07 hrs HW=145.32' (Free Discharge) 1=Culvert (Inlet Controls 0.41 cfs @ 1.92 fps) Summary for Pond 2D: DMH2 Inflow Area = 1.049 ac, 98.66% Impervious, Inflow Depth > 3.60" for 5-Year event Inflow = 4.29 cfs @ 12.07 hrs, Volume= 0.314 af Outflow = 4.29 cfs @ 12.07 hrs, Volume= 0.314 af, Atten= 0%, Lag= 0.0 min Primary = 4.29 cfs @ 12.07 hrs, Volume= 0.314 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 144.80' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.63'18.0" Round 18" CPEP L= 50.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.63' / 143.38' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=4.29 cfs @ 12.07 hrs HW=144.80' (Free Discharge) 1=18" CPEP (Barrel Controls 4.29 cfs @ 4.00 fps) Summary for Pond 2P: POST FRONT Inflow Area = 1.716 ac, 80.40% Impervious, Inflow Depth > 2.18" for 5-Year event Inflow = 5.61 cfs @ 12.08 hrs, Volume= 0.312 af Outflow = 2.65 cfs @ 12.27 hrs, Volume= 0.277 af, Atten= 53%, Lag= 11.4 min Primary = 2.65 cfs @ 12.27 hrs, Volume= 0.277 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Starting Elev= 144.27' Surf.Area= 2,195 sf Storage= 940 cf Peak Elev= 145.71' @ 12.27 hrs Surf.Area= 3,360 sf Storage= 6,027 cf (5,087 cf above start) Flood Elev= 148.20' Surf.Area= 508 sf Storage= 8,258 cf (7,318 cf above start) Plug-Flow detention time= 90.1 min calculated for 0.256 af (82% of inflow) Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 63HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Center-of-Mass det. time= 45.1 min ( 800.6 - 755.4 ) Volume Invert Avail.Storage Storage Description #1 143.90' 509 cf 4.00'D x 4.50'H DMH x 9 #2 143.86' 226 cf 30.0" Round 30" Flat CPEP (10-11) L= 46.0' S= 0.0070 '/' #3 143.74' 324 cf 30.0" Round 30" Flat CPEP (11-12) L= 66.0' S= 0.0003 '/' #4 143.78' 275 cf 30.0" Round 30" Flat CPEP (12-Out) L= 56.0' S= 0.0016 '/' #5 143.88' 1,924 cf 30.0" Round 30" Flat CPEP (9-Out) x 4 L= 98.0' S= 0.0030 '/' #6 143.39' 1,031 cf 30.0" Round 30" Flat CPEP (6-9) x 3 L= 70.0' S= 0.0007 '/' #7 143.59' 260 cf 30.0" Round 30" Flat CPEP (8-9) L= 53.0' S= 0.0008 '/' #8 143.38' 476 cf 30.0" Round 30" Flat CPEP (7-8) L= 97.0' S= 0.0008 '/' #9 143.39' 285 cf 30.0" Round 30" Flat CPEP (5-6) L= 58.0' S= 0.0007 '/' #10 143.50' 422 cf 30.0" Round 30" Flat CPEP (4-5) L= 86.0' S= 0.0003 '/' #11 148.00' 333 cf Custom Stage Data (Prismatic) Listed below (Recalc) #12 144.27' 2,376 cf 30.0" Round Prop. 30" Flat CPEP L= 484.0' #13 144.27' 113 cf 4.00'D x 4.50'H Prop. DMH x 2 8,554 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 370 0 0 148.90 370 333 333 Device Routing Invert Outlet Devices #1 Device 3 144.27'10.0" Vert. 10" Orifice C= 0.600 #2 Device 3 146.85'36.0" W x 4.0" H Vert. 4"x36" Weir/Orifice C= 0.600 #3 Primary 144.65'12.0" Round 12" Culvert L= 16.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.65' / 143.50' S= 0.0719 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Primary 148.00'37.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=2.65 cfs @ 12.27 hrs HW=145.71' (Free Discharge) 3=12" Culvert (Passes 2.65 cfs of 2.82 cfs potential flow) 1=10" Orifice (Orifice Controls 2.65 cfs @ 4.86 fps) 2=4"x36" Weir/Orifice ( Controls 0.00 cfs) 4=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 64HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 3C: CB3 Inflow Area = 0.158 ac, 97.82% Impervious, Inflow Depth > 3.55" for 5-Year event Inflow = 0.64 cfs @ 12.07 hrs, Volume= 0.047 af Outflow = 0.64 cfs @ 12.07 hrs, Volume= 0.047 af, Atten= 0%, Lag= 0.0 min Primary = 0.64 cfs @ 12.07 hrs, Volume= 0.047 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.24' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 13.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0115 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.64 cfs @ 12.07 hrs HW=145.24' (Free Discharge) 1=Culvert (Barrel Controls 0.64 cfs @ 2.87 fps) Summary for Pond 3D: DMH3 Inflow Area = 1.247 ac, 96.07% Impervious, Inflow Depth > 3.49" for 5-Year event Inflow = 5.02 cfs @ 12.07 hrs, Volume= 0.363 af Outflow = 5.02 cfs @ 12.07 hrs, Volume= 0.363 af, Atten= 0%, Lag= 0.0 min Primary = 5.02 cfs @ 12.07 hrs, Volume= 0.363 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 144.57' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.30'18.0" Round Culvert L= 54.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.30' / 143.00' S= 0.0056 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=5.02 cfs @ 12.07 hrs HW=144.57' (Free Discharge) 1=Culvert (Barrel Controls 5.02 cfs @ 4.24 fps) Summary for Pond 4C: CB4 Inflow Area = 0.199 ac, 82.34% Impervious, Inflow Depth > 2.92" for 5-Year event Inflow = 0.72 cfs @ 12.07 hrs, Volume= 0.048 af Outflow = 0.72 cfs @ 12.07 hrs, Volume= 0.048 af, Atten= 0%, Lag= 0.0 min Primary = 0.72 cfs @ 12.07 hrs, Volume= 0.048 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.25' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 65HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0188 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.72 cfs @ 12.07 hrs HW=145.25' (Free Discharge) 1=Culvert (Barrel Controls 0.72 cfs @ 3.06 fps) Summary for Pond 9P: RG9 Inflow Area = 0.258 ac, 77.08% Impervious, Inflow Depth > 2.83" for 5-Year event Inflow = 0.92 cfs @ 12.07 hrs, Volume= 0.061 af Outflow = 0.59 cfs @ 12.16 hrs, Volume= 0.061 af, Atten= 36%, Lag= 5.2 min Discarded = 0.02 cfs @ 12.16 hrs, Volume= 0.003 af Primary = 0.57 cfs @ 12.16 hrs, Volume= 0.058 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.59' @ 12.16 hrs Surf.Area= 769 sf Storage= 164 cf Flood Elev= 148.40' Surf.Area= 1,804 sf Storage= 1,004 cf Plug-Flow detention time= 1.9 min calculated for 0.061 af (100% of inflow) Center-of-Mass det. time= 1.6 min ( 767.4 - 765.8 ) Volume Invert Avail.Storage Storage Description #1 147.40' 963 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 145.60' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 145.60' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,004 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.40 632 0 0 148.00 853 445 445 148.40 1,736 518 963 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 145.60'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 34.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 143.94' S= 0.0165 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 145.60'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 66HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.02 cfs @ 12.16 hrs HW=147.59' (Free Discharge) 2=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=0.57 cfs @ 12.16 hrs HW=147.59' (Free Discharge) 3=Culvert (Passes 0.57 cfs of 6.08 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.57 cfs @ 6.49 fps) Summary for Pond 12P: RG12 Inflow Area = 0.229 ac, 48.28% Impervious, Inflow Depth > 1.88" for 5-Year event Inflow = 0.56 cfs @ 12.08 hrs, Volume= 0.036 af Outflow = 0.51 cfs @ 12.11 hrs, Volume= 0.036 af, Atten= 10%, Lag= 2.2 min Discarded = 0.01 cfs @ 12.11 hrs, Volume= 0.002 af Primary = 0.50 cfs @ 12.11 hrs, Volume= 0.034 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.57' @ 12.11 hrs Surf.Area= 318 sf Storage= 50 cf Flood Elev= 148.40' Surf.Area= 3,301 sf Storage= 1,481 cf Plug-Flow detention time= 1.4 min calculated for 0.036 af (100% of inflow) Center-of-Mass det. time= 1.1 min ( 796.8 - 795.7 ) Volume Invert Avail.Storage Storage Description #1 147.50' 1,440 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,481 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 1,764 441 441 148.40 3,233 999 1,440 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 19.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.09' S= 0.0216 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 67HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.01 cfs @ 12.11 hrs HW=147.57' (Free Discharge) 2=Exfiltration ( Controls 0.01 cfs) Primary OutFlow Max=0.50 cfs @ 12.11 hrs HW=147.57' (Free Discharge) 3=Culvert (Passes 0.50 cfs of 6.06 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.50 cfs @ 5.70 fps) Summary for Pond 13P: RG13 Inflow Area = 0.079 ac, 73.59% Impervious, Inflow Depth > 2.64" for 5-Year event Inflow = 0.27 cfs @ 12.07 hrs, Volume= 0.017 af Outflow = 0.26 cfs @ 12.09 hrs, Volume= 0.017 af, Atten= 2%, Lag= 0.9 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.001 af Primary = 0.26 cfs @ 12.09 hrs, Volume= 0.016 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.55' @ 12.09 hrs Surf.Area= 36 sf Storage= 10 cf Flood Elev= 148.70' Surf.Area= 1,047 sf Storage= 282 cf Plug-Flow detention time= 0.9 min calculated for 0.017 af (100% of inflow) Center-of-Mass det. time= 0.7 min ( 773.0 - 772.4 ) Volume Invert Avail.Storage Storage Description #1 147.50' 261 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 13 cf 3.21'W x 11.33'L x 1.21'H Field A 44 cf Overall - 10 cf Embedded = 33 cf x 40.0% Voids #3A 146.00' 8 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf Row Length Adjustment= -10.00' x 0.81 sf x 1 rows 282 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 127 32 32 148.40 249 75 107 148.50 269 26 133 148.70 1,011 128 261 Device Routing Invert Outlet Devices #1 Device 3 148.30'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.10'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 68HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 145.10' / 144.84' S= 0.0260 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=146.55' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.26 cfs @ 12.09 hrs HW=146.55' (Free Discharge) 3=Culvert (Passes 0.26 cfs of 3.69 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.26 cfs @ 2.98 fps) Summary for Pond 14P: RG14 Inflow Area = 0.050 ac, 59.73% Impervious, Inflow Depth > 2.20" for 5-Year event Inflow = 0.14 cfs @ 12.07 hrs, Volume= 0.009 af Outflow = 0.14 cfs @ 12.09 hrs, Volume= 0.009 af, Atten= 2%, Lag= 0.8 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.001 af Primary = 0.14 cfs @ 12.09 hrs, Volume= 0.008 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.28' @ 12.09 hrs Surf.Area= 68 sf Storage= 8 cf Flood Elev= 148.70' Surf.Area= 1,131 sf Storage= 357 cf Plug-Flow detention time= 1.9 min calculated for 0.009 af (100% of inflow) Center-of-Mass det. time= 1.5 min ( 787.7 - 786.2 ) Volume Invert Avail.Storage Storage Description #1 148.00' 316 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 357 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 0 0 0 148.30 331 50 50 148.40 450 39 89 148.70 1,063 227 316 Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.26'12.0" Round Culvert Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 69HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.10' / 145.26' S= -0.0160 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=146.28' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.14 cfs @ 12.09 hrs HW=146.28' (Free Discharge) 3=Culvert (Passes 0.14 cfs of 2.44 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.14 cfs @ 1.79 fps) Summary for Pond 15P: RG15 Inflow Area = 0.065 ac, 51.91% Impervious, Inflow Depth > 1.96" for 5-Year event Inflow = 0.17 cfs @ 12.08 hrs, Volume= 0.011 af Outflow = 0.16 cfs @ 12.09 hrs, Volume= 0.011 af, Atten= 2%, Lag= 0.9 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.001 af Primary = 0.16 cfs @ 12.09 hrs, Volume= 0.009 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.31' @ 12.09 hrs Surf.Area= 68 sf Storage= 9 cf Flood Elev= 148.70' Surf.Area= 880 sf Storage= 337 cf Plug-Flow detention time= 1.8 min calculated for 0.011 af (100% of inflow) Center-of-Mass det. time= 1.3 min ( 794.7 - 793.4 ) Volume Invert Avail.Storage Storage Description #1 147.80' 296 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 337 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.80 0 0 0 148.00 173 17 17 148.30 300 71 88 148.40 354 33 121 148.70 812 175 296 Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 70HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.20'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.20' / 144.84' S= 0.0360 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=146.31' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.16 cfs @ 12.09 hrs HW=146.31' (Free Discharge) 3=Culvert (Passes 0.16 cfs of 2.96 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.16 cfs @ 1.90 fps) Summary for Pond 16P: INF-10+11 Inflow Area = 0.368 ac, 90.56% Impervious, Inflow Depth > 3.31" for 5-Year event Inflow = 1.45 cfs @ 12.07 hrs, Volume= 0.102 af Outflow = 1.45 cfs @ 12.07 hrs, Volume= 0.092 af, Atten= 0%, Lag= 0.0 min Discarded = 0.03 cfs @ 12.07 hrs, Volume= 0.034 af Primary = 1.42 cfs @ 12.07 hrs, Volume= 0.058 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.27' @ 12.07 hrs Surf.Area= 909 sf Storage= 494 cf Flood Elev= 149.00' Surf.Area= 11,205 sf Storage= 3,082 cf Plug-Flow detention time= 54.4 min calculated for 0.092 af (91% of inflow) Center-of-Mass det. time= 22.2 min ( 766.4 - 744.2 ) Volume Invert Avail.Storage Storage Description #1 146.00' 271 cf Stone Bedding (Prismatic) Listed below (Recalc) 897 cf Overall - 219 cf Embedded = 678 cf x 40.0% Voids #2 146.08' 219 cf 10.0" Round Pipe Storage Inside #1 L= 402.0' #3 147.00' 2,592 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,082 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 897 0 0 147.00 897 897 897 Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 71HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 5,154 1,290 1,296 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.70'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.44' S= 0.0081 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.80'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0194 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.03 cfs @ 12.07 hrs HW=147.27' (Free Discharge) 5=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=1.41 cfs @ 12.07 hrs HW=147.27' (Free Discharge) 2=Culvert (Passes 0.71 cfs of 5.45 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.71 cfs @ 1.37 fps) 4=Culvert (Passes 0.71 cfs of 5.31 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.71 cfs @ 1.37 fps) Summary for Pond 17P: INF-6+8 Inflow Area = 0.293 ac, 88.50% Impervious, Inflow Depth > 3.18" for 5-Year event Inflow = 1.13 cfs @ 12.07 hrs, Volume= 0.078 af Outflow = 1.16 cfs @ 12.06 hrs, Volume= 0.072 af, Atten= 0%, Lag= 0.0 min Discarded = 0.02 cfs @ 12.06 hrs, Volume= 0.022 af Primary = 1.14 cfs @ 12.06 hrs, Volume= 0.050 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.04' @ 12.06 hrs Surf.Area= 628 sf Storage= 334 cf Flood Elev= 148.90' Surf.Area= 14,038 sf Storage= 3,704 cf Plug-Flow detention time= 43.9 min calculated for 0.072 af (92% of inflow) Center-of-Mass det. time= 16.9 min ( 768.4 - 751.5 ) Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 72HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Volume Invert Avail.Storage Storage Description #1 146.00' 188 cf Stone Bedding (Prismatic) Listed below (Recalc) 616 cf Overall - 146 cf Embedded = 470 cf x 40.0% Voids #2 146.08' 146 cf 10.0" Round Pipe Storage Inside #1 L= 267.0' #3 147.00' 3,371 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,704 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 616 0 0 147.00 616 616 616 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 6,711 1,679 1,685 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.80'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.32' S= 0.0155 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.50'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.15' S= 0.0113 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.02 cfs @ 12.06 hrs HW=147.04' (Free Discharge) 5=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=1.12 cfs @ 12.06 hrs HW=147.04' (Free Discharge) 2=Culvert (Passes 0.00 cfs of 4.99 cfs potential flow) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 4=Culvert (Passes 1.12 cfs of 5.40 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 1.12 cfs @ 1.60 fps) Summary for Pond 18P: INF-5+7 Inflow Area = 0.214 ac, 91.42% Impervious, Inflow Depth > 3.33" for 5-Year event Inflow = 0.85 cfs @ 12.07 hrs, Volume= 0.059 af Outflow = 0.85 cfs @ 12.07 hrs, Volume= 0.054 af, Atten= 0%, Lag= 0.0 min Discarded = 0.03 cfs @ 12.07 hrs, Volume= 0.025 af Primary = 0.82 cfs @ 12.07 hrs, Volume= 0.029 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 5-Year Rainfall=4.08"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 73HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev= 146.97' @ 12.07 hrs Surf.Area= 664 sf Storage= 357 cf Flood Elev= 148.90' Surf.Area= 5,822 sf Storage= 1,665 cf Plug-Flow detention time= 63.8 min calculated for 0.054 af (91% of inflow) Center-of-Mass det. time= 31.9 min ( 776.1 - 744.2 ) Volume Invert Avail.Storage Storage Description #1 145.60' 199 cf Stone Bedding (Prismatic) Listed below (Recalc) 652 cf Overall - 154 cf Embedded = 498 cf x 40.0% Voids #2 145.68' 154 cf 10.0" Round Pipe Storage Inside #1 L= 282.0' #3 146.60' 1,312 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 1,665 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 145.60 652 0 0 146.60 652 652 652 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.60 6 0 0 148.00 6 8 8 148.50 2,585 648 656 Device Routing Invert Outlet Devices #1 Device 2 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.60'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.60' / 144.32' S= 0.0097 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.90'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.70'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.15' S= 0.0190 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 145.60'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.03 cfs @ 12.07 hrs HW=146.97' (Free Discharge) 5=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=0.81 cfs @ 12.07 hrs HW=146.97' (Free Discharge) 2=Culvert (Passes 0.65 cfs of 5.16 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.65 cfs @ 1.33 fps) 4=Culvert (Passes 0.16 cfs of 5.02 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.16 cfs @ 0.83 fps) Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 74HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Time span=1.00-20.00 hrs, dt=0.01 hrs, 1901 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Runoff Area=8,350 sf 98.42% Impervious Runoff Depth>4.34"Subcatchment 1S: A1 Tc=5.0 min CN=97 Runoff=0.95 cfs 0.069 af Runoff Area=4,496 sf 92.70% Impervious Runoff Depth>4.12"Subcatchment 2S: A2 Tc=5.0 min CN=95 Runoff=0.50 cfs 0.035 af Runoff Area=6,870 sf 97.82% Impervious Runoff Depth>4.34"Subcatchment 3S: A3 Tc=5.0 min CN=97 Runoff=0.78 cfs 0.057 af Runoff Area=8,648 sf 82.34% Impervious Runoff Depth>3.69"Subcatchment 4S: A4 Tc=5.0 min CN=91 Runoff=0.90 cfs 0.061 af Runoff Area=25,964 sf 100.00% Impervious Runoff Depth>4.46"Subcatchment 5S: B2 Tc=5.0 min CN=98 Runoff=2.97 cfs 0.221 af Runoff Area=7,072 sf 0.00% Impervious Runoff Depth>1.19"Subcatchment 6S: POND Tc=0.0 min CN=61 Runoff=0.28 cfs 0.016 af Runoff Area=57,882 sf 0.00% Impervious Runoff Depth>3.69"Subcatchment 7S: PRE REAR Tc=5.0 min CN=91 Runoff=6.03 cfs 0.408 af Runoff Area=5,095 sf 91.89% Impervious Runoff Depth>4.12"Subcatchment 8S: A5 Tc=5.0 min CN=95 Runoff=0.57 cfs 0.040 af Runoff Area=6,947 sf 89.75% Impervious Runoff Depth>4.01"Subcatchment 9S: A6 Tc=5.0 min CN=94 Runoff=0.76 cfs 0.053 af Runoff Area=4,230 sf 90.85% Impervious Runoff Depth>4.12"Subcatchment 10S: A7 Tc=5.0 min CN=95 Runoff=0.47 cfs 0.033 af Runoff Area=5,823 sf 87.02% Impervious Runoff Depth>3.90"Subcatchment 11S: A8 Tc=5.0 min CN=93 Runoff=0.63 cfs 0.043 af Runoff Area=11,231 sf 77.08% Impervious Runoff Depth>3.58"Subcatchment 12S: A9 Tc=5.0 min CN=90 Runoff=1.15 cfs 0.077 af Runoff Area=9,635 sf 93.98% Impervious Runoff Depth>4.23"Subcatchment 13S: A10 Tc=5.0 min CN=96 Runoff=1.08 cfs 0.078 af Runoff Area=6,395 sf 85.41% Impervious Runoff Depth>3.90"Subcatchment 14S: A11 Tc=5.0 min CN=93 Runoff=0.69 cfs 0.048 af Runoff Area=9,957 sf 48.28% Impervious Runoff Depth>2.54"Subcatchment 15S: A12 Tc=5.0 min CN=79 Runoff=0.76 cfs 0.048 af Runoff Area=3,453 sf 73.59% Impervious Runoff Depth>3.38"Subcatchment 16S: A13 Tc=5.0 min CN=88 Runoff=0.34 cfs 0.022 af Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 75HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Runoff Area=2,168 sf 59.73% Impervious Runoff Depth>2.90"Subcatchment 17S: A14 Tc=5.0 min CN=83 Runoff=0.19 cfs 0.012 af Runoff Area=2,826 sf 51.91% Impervious Runoff Depth>2.63"Subcatchment 18S: A15 Tc=5.0 min CN=80 Runoff=0.22 cfs 0.014 af Runoff Area=6,971 sf 100.00% Impervious Runoff Depth>4.46"Subcatchment 19S: B1 Tc=5.0 min CN=98 Runoff=0.80 cfs 0.059 af Runoff Area=71,761 sf 44.08% Impervious Runoff Depth>3.48"Subcatchment 20S: PRE FRONT Tc=5.0 min CN=89 Runoff=7.17 cfs 0.478 af Peak Elev=145.36' Inflow=0.95 cfs 0.069 afPond 1C: CB1 12.0" Round Culvert n=0.012 L=124.0' S=0.0050 '/' Outflow=0.95 cfs 0.069 af Peak Elev=145.18' Inflow=4.41 cfs 0.326 afPond 1D: DMH1 18.0" Round Culvert n=0.012 L=58.0' S=0.0050 '/' Outflow=4.41 cfs 0.326 af Peak Elev=146.68' Storage=9,882 cf Inflow=6.28 cfs 0.460 afPond 1P: POST REAR Discarded=0.13 cfs 0.113 af Primary=2.41 cfs 0.142 af Outflow=2.54 cfs 0.254 af Peak Elev=145.35' Inflow=0.50 cfs 0.035 afPond 2C: CB2 12.0" Round Culvert n=0.012 L=8.0' S=0.0437 '/' Outflow=0.50 cfs 0.035 af Peak Elev=144.95' Inflow=5.19 cfs 0.383 afPond 2D: DMH2 18.0" Round Culvert n=0.012 L=50.0' S=0.0050 '/' Outflow=5.19 cfs 0.383 af Peak Elev=146.11' Storage=7,128 cf Inflow=6.67 cfs 0.411 afPond 2P: POST FRONT Outflow=3.13 cfs 0.375 af Peak Elev=145.29' Inflow=0.78 cfs 0.057 afPond 3C: CB3 12.0" Round Culvert n=0.012 L=13.0' S=0.0115 '/' Outflow=0.78 cfs 0.057 af Peak Elev=144.75' Inflow=6.09 cfs 0.444 afPond 3D: DMH3 18.0" Round Culvert n=0.012 L=54.0' S=0.0056 '/' Outflow=6.09 cfs 0.444 af Peak Elev=145.32' Inflow=0.90 cfs 0.061 afPond 4C: CB4 12.0" Round Culvert n=0.012 L=8.0' S=0.0188 '/' Outflow=0.90 cfs 0.061 af Peak Elev=147.75' Storage=283 cf Inflow=1.15 cfs 0.077 afPond 9P: RG9 Discarded=0.02 cfs 0.003 af Primary=0.59 cfs 0.074 af Outflow=0.61 cfs 0.077 af Peak Elev=147.70' Storage=113 cf Inflow=0.76 cfs 0.048 afPond 12P: RG12 Discarded=0.02 cfs 0.002 af Primary=0.52 cfs 0.046 af Outflow=0.54 cfs 0.048 af Peak Elev=146.77' Storage=14 cf Inflow=0.34 cfs 0.022 afPond 13P: RG13 Discarded=0.00 cfs 0.001 af Primary=0.33 cfs 0.021 af Outflow=0.33 cfs 0.022 af Peak Elev=146.35' Storage=11 cf Inflow=0.19 cfs 0.012 afPond 14P: RG14 Discarded=0.00 cfs 0.002 af Primary=0.18 cfs 0.010 af Outflow=0.18 cfs 0.012 af Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 76HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev=146.42' Storage=13 cf Inflow=0.22 cfs 0.014 afPond 15P: RG15 Discarded=0.00 cfs 0.002 af Primary=0.21 cfs 0.013 af Outflow=0.21 cfs 0.014 af Peak Elev=147.30' Storage=494 cf Inflow=1.77 cfs 0.126 afPond 16P: INF-10+11 Discarded=0.04 cfs 0.036 af Primary=1.74 cfs 0.079 af Outflow=1.77 cfs 0.115 af Peak Elev=147.07' Storage=335 cf Inflow=1.39 cfs 0.097 afPond 17P: INF-6+8 Discarded=0.02 cfs 0.023 af Primary=1.36 cfs 0.067 af Outflow=1.38 cfs 0.090 af Peak Elev=146.98' Storage=358 cf Inflow=1.04 cfs 0.073 afPond 18P: INF-5+7 Discarded=0.03 cfs 0.027 af Primary=1.01 cfs 0.040 af Outflow=1.04 cfs 0.067 af Total Runoff Area = 6.101 ac Runoff Volume = 1.875 af Average Runoff Depth = 3.69" 45.85% Pervious = 2.798 ac 54.15% Impervious = 3.304 ac Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 77HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: A1 Runoff = 0.95 cfs @ 12.07 hrs, Volume= 0.069 af, Depth> 4.34" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 8,218 98 Paved parking, HSG B 132 61 >75% Grass cover, Good, HSG B 8,350 97 Weighted Average 132 1.58% Pervious Area 8,218 98.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: A2 Runoff = 0.50 cfs @ 12.07 hrs, Volume= 0.035 af, Depth> 4.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 4,168 98 Paved parking, HSG B 328 61 >75% Grass cover, Good, HSG B 4,496 95 Weighted Average 328 7.30% Pervious Area 4,168 92.70% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 3S: A3 Runoff = 0.78 cfs @ 12.07 hrs, Volume= 0.057 af, Depth> 4.34" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 6,720 98 Paved parking, HSG B 150 61 >75% Grass cover, Good, HSG B 6,870 97 Weighted Average 150 2.18% Pervious Area 6,720 97.82% Impervious Area Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 78HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 4S: A4 Runoff = 0.90 cfs @ 12.07 hrs, Volume= 0.061 af, Depth> 3.69" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 7,121 98 Paved parking, HSG B 1,527 61 >75% Grass cover, Good, HSG B 8,648 91 Weighted Average 1,527 17.66% Pervious Area 7,121 82.34% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: B2 Runoff = 2.97 cfs @ 12.07 hrs, Volume= 0.221 af, Depth> 4.46" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 25,964 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 25,964 98 Weighted Average 25,964 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 6S: POND Runoff = 0.28 cfs @ 12.00 hrs, Volume= 0.016 af, Depth> 1.19" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 79HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 7,072 61 >75% Grass cover, Good, HSG B 7,072 100.00% Pervious Area Summary for Subcatchment 7S: PRE REAR Runoff = 6.03 cfs @ 12.07 hrs, Volume= 0.408 af, Depth> 3.69" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 9,064 67 Brush, Poor, HSG B 48,818 96 Gravel surface, HSG B 57,882 91 Weighted Average 57,882 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 8S: A5 Runoff = 0.57 cfs @ 12.07 hrs, Volume= 0.040 af, Depth> 4.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 4,682 98 Paved parking, HSG B 413 61 >75% Grass cover, Good, HSG B 5,095 95 Weighted Average 413 8.11% Pervious Area 4,682 91.89% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: A6 Runoff = 0.76 cfs @ 12.07 hrs, Volume= 0.053 af, Depth> 4.01" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 80HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 6,235 98 Paved parking, HSG B 712 61 >75% Grass cover, Good, HSG B 6,947 94 Weighted Average 712 10.25% Pervious Area 6,235 89.75% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 10S: A7 Runoff = 0.47 cfs @ 12.07 hrs, Volume= 0.033 af, Depth> 4.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 3,843 98 Paved parking, HSG B 387 61 >75% Grass cover, Good, HSG B 4,230 95 Weighted Average 387 9.15% Pervious Area 3,843 90.85% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 11S: A8 Runoff = 0.63 cfs @ 12.07 hrs, Volume= 0.043 af, Depth> 3.90" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 5,067 98 Paved parking, HSG B 756 61 >75% Grass cover, Good, HSG B 5,823 93 Weighted Average 756 12.98% Pervious Area 5,067 87.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 81HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 12S: A9 Runoff = 1.15 cfs @ 12.07 hrs, Volume= 0.077 af, Depth> 3.58" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 8,657 98 Paved parking, HSG B 2,574 61 >75% Grass cover, Good, HSG B 11,231 90 Weighted Average 2,574 22.92% Pervious Area 8,657 77.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 13S: A10 Runoff = 1.08 cfs @ 12.07 hrs, Volume= 0.078 af, Depth> 4.23" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 9,055 98 Paved parking, HSG B 580 61 >75% Grass cover, Good, HSG B 9,635 96 Weighted Average 580 6.02% Pervious Area 9,055 93.98% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 14S: A11 Runoff = 0.69 cfs @ 12.07 hrs, Volume= 0.048 af, Depth> 3.90" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 5,462 98 Paved parking, HSG B 933 61 >75% Grass cover, Good, HSG B 6,395 93 Weighted Average 933 14.59% Pervious Area 5,462 85.41% Impervious Area Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 82HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 15S: A12 Runoff = 0.76 cfs @ 12.07 hrs, Volume= 0.048 af, Depth> 2.54" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 4,807 98 Paved parking, HSG B 5,150 61 >75% Grass cover, Good, HSG B 9,957 79 Weighted Average 5,150 51.72% Pervious Area 4,807 48.28% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 16S: A13 Runoff = 0.34 cfs @ 12.07 hrs, Volume= 0.022 af, Depth> 3.38" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 2,541 98 Paved parking, HSG B 912 61 >75% Grass cover, Good, HSG B 3,453 88 Weighted Average 912 26.41% Pervious Area 2,541 73.59% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 17S: A14 Runoff = 0.19 cfs @ 12.07 hrs, Volume= 0.012 af, Depth> 2.90" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 83HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 1,295 98 Paved parking, HSG B 873 61 >75% Grass cover, Good, HSG B 2,168 83 Weighted Average 873 40.27% Pervious Area 1,295 59.73% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 18S: A15 Runoff = 0.22 cfs @ 12.07 hrs, Volume= 0.014 af, Depth> 2.63" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 1,467 98 Paved parking, HSG B 1,359 61 >75% Grass cover, Good, HSG B 2,826 80 Weighted Average 1,359 48.09% Pervious Area 1,467 51.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 19S: B1 Runoff = 0.80 cfs @ 12.07 hrs, Volume= 0.059 af, Depth> 4.46" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 6,971 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 6,971 98 Weighted Average 6,971 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 84HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 20S: PRE FRONT Runoff = 7.17 cfs @ 12.07 hrs, Volume= 0.478 af, Depth> 3.48" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91" Area (sf) CN Description 24,527 96 Gravel surface, HSG B 15,601 61 >75% Grass cover, Good, HSG B 31,633 98 Paved parking, HSG B 71,761 89 Weighted Average 40,128 55.92% Pervious Area 31,633 44.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Pond 1C: CB1 Inflow Area = 0.192 ac, 98.42% Impervious, Inflow Depth > 4.34" for 10-Year event Inflow = 0.95 cfs @ 12.07 hrs, Volume= 0.069 af Outflow = 0.95 cfs @ 12.07 hrs, Volume= 0.069 af, Atten= 0%, Lag= 0.0 min Primary = 0.95 cfs @ 12.07 hrs, Volume= 0.069 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.36' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 124.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.95 cfs @ 12.07 hrs HW=145.36' (Free Discharge) 1=Culvert (Barrel Controls 0.95 cfs @ 3.02 fps) Summary for Pond 1D: DMH1 Inflow Area = 0.891 ac, 98.81% Impervious, Inflow Depth > 4.39" for 10-Year event Inflow = 4.41 cfs @ 12.07 hrs, Volume= 0.326 af Outflow = 4.41 cfs @ 12.07 hrs, Volume= 0.326 af, Atten= 0%, Lag= 0.0 min Primary = 4.41 cfs @ 12.07 hrs, Volume= 0.326 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.18' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.00'18.0" Round 18" CPEP Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 85HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 58.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.00' / 143.71' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=4.41 cfs @ 12.07 hrs HW=145.18' (Free Discharge) 1=18" CPEP (Barrel Controls 4.41 cfs @ 4.05 fps) Summary for Pond 1P: POST REAR Inflow Area = 1.410 ac, 85.00% Impervious, Inflow Depth > 3.92" for 10-Year event Inflow = 6.28 cfs @ 12.07 hrs, Volume= 0.460 af Outflow = 2.54 cfs @ 12.26 hrs, Volume= 0.254 af, Atten= 60%, Lag= 11.8 min Discarded = 0.13 cfs @ 12.26 hrs, Volume= 0.113 af Primary = 2.41 cfs @ 12.26 hrs, Volume= 0.142 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.68' @ 12.26 hrs Surf.Area= 4,274 sf Storage= 9,882 cf Plug-Flow detention time= 163.2 min calculated for 0.254 af (55% of inflow) Center-of-Mass det. time= 70.6 min ( 802.6 - 732.0 ) Volume Invert Avail.Storage Storage Description #1 143.00' 11,310 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 143.00 1,320 0 0 144.00 1,986 1,653 1,653 145.00 2,752 2,369 4,022 146.00 3,619 3,186 7,208 147.00 4,586 4,103 11,310 Device Routing Invert Outlet Devices #1 Discarded 143.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 135.00' #2 Primary 146.50'12.0' long x 16.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Discarded OutFlow Max=0.13 cfs @ 12.26 hrs HW=146.68' (Free Discharge) 1=Exfiltration ( Controls 0.13 cfs) Primary OutFlow Max=2.41 cfs @ 12.26 hrs HW=146.68' (Free Discharge) 2=Broad-Crested Rectangular Weir (Weir Controls 2.41 cfs @ 1.13 fps) Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 86HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 2C: CB2 Inflow Area = 0.103 ac, 92.70% Impervious, Inflow Depth > 4.12" for 10-Year event Inflow = 0.50 cfs @ 12.07 hrs, Volume= 0.035 af Outflow = 0.50 cfs @ 12.07 hrs, Volume= 0.035 af, Atten= 0%, Lag= 0.0 min Primary = 0.50 cfs @ 12.07 hrs, Volume= 0.035 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.35' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 145.00'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.00' / 144.65' S= 0.0437 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.50 cfs @ 12.07 hrs HW=145.35' (Free Discharge) 1=Culvert (Inlet Controls 0.50 cfs @ 2.02 fps) Summary for Pond 2D: DMH2 Inflow Area = 1.049 ac, 98.66% Impervious, Inflow Depth > 4.39" for 10-Year event Inflow = 5.19 cfs @ 12.07 hrs, Volume= 0.383 af Outflow = 5.19 cfs @ 12.07 hrs, Volume= 0.383 af, Atten= 0%, Lag= 0.0 min Primary = 5.19 cfs @ 12.07 hrs, Volume= 0.383 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 144.95' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.63'18.0" Round 18" CPEP L= 50.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.63' / 143.38' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=5.19 cfs @ 12.07 hrs HW=144.95' (Free Discharge) 1=18" CPEP (Barrel Controls 5.19 cfs @ 4.18 fps) Summary for Pond 2P: POST FRONT Inflow Area = 1.716 ac, 80.40% Impervious, Inflow Depth > 2.87" for 10-Year event Inflow = 6.67 cfs @ 12.07 hrs, Volume= 0.411 af Outflow = 3.13 cfs @ 12.29 hrs, Volume= 0.375 af, Atten= 53%, Lag= 13.1 min Primary = 3.13 cfs @ 12.29 hrs, Volume= 0.375 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Starting Elev= 144.27' Surf.Area= 2,195 sf Storage= 940 cf Peak Elev= 146.11' @ 12.29 hrs Surf.Area= 2,187 sf Storage= 7,128 cf (6,188 cf above start) Flood Elev= 148.20' Surf.Area= 508 sf Storage= 8,258 cf (7,318 cf above start) Plug-Flow detention time= 81.9 min calculated for 0.353 af (86% of inflow) Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 87HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Center-of-Mass det. time= 42.8 min ( 796.7 - 753.9 ) Volume Invert Avail.Storage Storage Description #1 143.90' 509 cf 4.00'D x 4.50'H DMH x 9 #2 143.86' 226 cf 30.0" Round 30" Flat CPEP (10-11) L= 46.0' S= 0.0070 '/' #3 143.74' 324 cf 30.0" Round 30" Flat CPEP (11-12) L= 66.0' S= 0.0003 '/' #4 143.78' 275 cf 30.0" Round 30" Flat CPEP (12-Out) L= 56.0' S= 0.0016 '/' #5 143.88' 1,924 cf 30.0" Round 30" Flat CPEP (9-Out) x 4 L= 98.0' S= 0.0030 '/' #6 143.39' 1,031 cf 30.0" Round 30" Flat CPEP (6-9) x 3 L= 70.0' S= 0.0007 '/' #7 143.59' 260 cf 30.0" Round 30" Flat CPEP (8-9) L= 53.0' S= 0.0008 '/' #8 143.38' 476 cf 30.0" Round 30" Flat CPEP (7-8) L= 97.0' S= 0.0008 '/' #9 143.39' 285 cf 30.0" Round 30" Flat CPEP (5-6) L= 58.0' S= 0.0007 '/' #10 143.50' 422 cf 30.0" Round 30" Flat CPEP (4-5) L= 86.0' S= 0.0003 '/' #11 148.00' 333 cf Custom Stage Data (Prismatic) Listed below (Recalc) #12 144.27' 2,376 cf 30.0" Round Prop. 30" Flat CPEP L= 484.0' #13 144.27' 113 cf 4.00'D x 4.50'H Prop. DMH x 2 8,554 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 370 0 0 148.90 370 333 333 Device Routing Invert Outlet Devices #1 Device 3 144.27'10.0" Vert. 10" Orifice C= 0.600 #2 Device 3 146.85'36.0" W x 4.0" H Vert. 4"x36" Weir/Orifice C= 0.600 #3 Primary 144.65'12.0" Round 12" Culvert L= 16.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.65' / 143.50' S= 0.0719 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Primary 148.00'37.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=3.13 cfs @ 12.29 hrs HW=146.11' (Free Discharge) 3=12" Culvert (Passes 3.13 cfs of 3.70 cfs potential flow) 1=10" Orifice (Orifice Controls 3.13 cfs @ 5.74 fps) 2=4"x36" Weir/Orifice ( Controls 0.00 cfs) 4=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 88HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 3C: CB3 Inflow Area = 0.158 ac, 97.82% Impervious, Inflow Depth > 4.34" for 10-Year event Inflow = 0.78 cfs @ 12.07 hrs, Volume= 0.057 af Outflow = 0.78 cfs @ 12.07 hrs, Volume= 0.057 af, Atten= 0%, Lag= 0.0 min Primary = 0.78 cfs @ 12.07 hrs, Volume= 0.057 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.29' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 13.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0115 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.78 cfs @ 12.07 hrs HW=145.29' (Free Discharge) 1=Culvert (Barrel Controls 0.78 cfs @ 2.99 fps) Summary for Pond 3D: DMH3 Inflow Area = 1.247 ac, 96.07% Impervious, Inflow Depth > 4.27" for 10-Year event Inflow = 6.09 cfs @ 12.07 hrs, Volume= 0.444 af Outflow = 6.09 cfs @ 12.07 hrs, Volume= 0.444 af, Atten= 0%, Lag= 0.0 min Primary = 6.09 cfs @ 12.07 hrs, Volume= 0.444 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 144.75' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.30'18.0" Round Culvert L= 54.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.30' / 143.00' S= 0.0056 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=6.09 cfs @ 12.07 hrs HW=144.75' (Free Discharge) 1=Culvert (Barrel Controls 6.09 cfs @ 4.44 fps) Summary for Pond 4C: CB4 Inflow Area = 0.199 ac, 82.34% Impervious, Inflow Depth > 3.69" for 10-Year event Inflow = 0.90 cfs @ 12.07 hrs, Volume= 0.061 af Outflow = 0.90 cfs @ 12.07 hrs, Volume= 0.061 af, Atten= 0%, Lag= 0.0 min Primary = 0.90 cfs @ 12.07 hrs, Volume= 0.061 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.32' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 89HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0188 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.90 cfs @ 12.07 hrs HW=145.32' (Free Discharge) 1=Culvert (Barrel Controls 0.90 cfs @ 3.19 fps) Summary for Pond 9P: RG9 Inflow Area = 0.258 ac, 77.08% Impervious, Inflow Depth > 3.58" for 10-Year event Inflow = 1.15 cfs @ 12.07 hrs, Volume= 0.077 af Outflow = 0.61 cfs @ 12.19 hrs, Volume= 0.077 af, Atten= 46%, Lag= 6.9 min Discarded = 0.02 cfs @ 12.19 hrs, Volume= 0.003 af Primary = 0.59 cfs @ 12.19 hrs, Volume= 0.074 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.75' @ 12.19 hrs Surf.Area= 828 sf Storage= 283 cf Flood Elev= 148.40' Surf.Area= 1,804 sf Storage= 1,004 cf Plug-Flow detention time= 2.6 min calculated for 0.077 af (100% of inflow) Center-of-Mass det. time= 2.4 min ( 762.5 - 760.1 ) Volume Invert Avail.Storage Storage Description #1 147.40' 963 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 145.60' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 145.60' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,004 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.40 632 0 0 148.00 853 445 445 148.40 1,736 518 963 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 145.60'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 34.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 143.94' S= 0.0165 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 145.60'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 90HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.02 cfs @ 12.19 hrs HW=147.75' (Free Discharge) 2=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=0.59 cfs @ 12.19 hrs HW=147.75' (Free Discharge) 3=Culvert (Passes 0.59 cfs of 6.27 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.59 cfs @ 6.78 fps) Summary for Pond 12P: RG12 Inflow Area = 0.229 ac, 48.28% Impervious, Inflow Depth > 2.54" for 10-Year event Inflow = 0.76 cfs @ 12.07 hrs, Volume= 0.048 af Outflow = 0.54 cfs @ 12.15 hrs, Volume= 0.048 af, Atten= 29%, Lag= 4.4 min Discarded = 0.02 cfs @ 12.15 hrs, Volume= 0.002 af Primary = 0.52 cfs @ 12.15 hrs, Volume= 0.046 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.70' @ 12.15 hrs Surf.Area= 781 sf Storage= 113 cf Flood Elev= 148.40' Surf.Area= 3,301 sf Storage= 1,481 cf Plug-Flow detention time= 1.7 min calculated for 0.048 af (100% of inflow) Center-of-Mass det. time= 1.4 min ( 790.2 - 788.9 ) Volume Invert Avail.Storage Storage Description #1 147.50' 1,440 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,481 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 1,764 441 441 148.40 3,233 999 1,440 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 19.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.09' S= 0.0216 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 91HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.02 cfs @ 12.15 hrs HW=147.70' (Free Discharge) 2=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=0.52 cfs @ 12.15 hrs HW=147.70' (Free Discharge) 3=Culvert (Passes 0.52 cfs of 6.22 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.52 cfs @ 5.97 fps) Summary for Pond 13P: RG13 Inflow Area = 0.079 ac, 73.59% Impervious, Inflow Depth > 3.38" for 10-Year event Inflow = 0.34 cfs @ 12.07 hrs, Volume= 0.022 af Outflow = 0.33 cfs @ 12.09 hrs, Volume= 0.022 af, Atten= 3%, Lag= 1.1 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.001 af Primary = 0.33 cfs @ 12.09 hrs, Volume= 0.021 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.77' @ 12.09 hrs Surf.Area= 36 sf Storage= 14 cf Flood Elev= 148.70' Surf.Area= 1,047 sf Storage= 282 cf Plug-Flow detention time= 0.9 min calculated for 0.022 af (100% of inflow) Center-of-Mass det. time= 0.7 min ( 767.1 - 766.4 ) Volume Invert Avail.Storage Storage Description #1 147.50' 261 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 13 cf 3.21'W x 11.33'L x 1.21'H Field A 44 cf Overall - 10 cf Embedded = 33 cf x 40.0% Voids #3A 146.00' 8 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf Row Length Adjustment= -10.00' x 0.81 sf x 1 rows 282 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 127 32 32 148.40 249 75 107 148.50 269 26 133 148.70 1,011 128 261 Device Routing Invert Outlet Devices #1 Device 3 148.30'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.10'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 92HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 145.10' / 144.84' S= 0.0260 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=146.77' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.33 cfs @ 12.09 hrs HW=146.77' (Free Discharge) 3=Culvert (Passes 0.33 cfs of 4.09 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.33 cfs @ 3.74 fps) Summary for Pond 14P: RG14 Inflow Area = 0.050 ac, 59.73% Impervious, Inflow Depth > 2.90" for 10-Year event Inflow = 0.19 cfs @ 12.07 hrs, Volume= 0.012 af Outflow = 0.18 cfs @ 12.09 hrs, Volume= 0.012 af, Atten= 3%, Lag= 1.1 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.002 af Primary = 0.18 cfs @ 12.09 hrs, Volume= 0.010 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.35' @ 12.09 hrs Surf.Area= 68 sf Storage= 11 cf Flood Elev= 148.70' Surf.Area= 1,131 sf Storage= 357 cf Plug-Flow detention time= 1.8 min calculated for 0.012 af (100% of inflow) Center-of-Mass det. time= 1.4 min ( 781.1 - 779.8 ) Volume Invert Avail.Storage Storage Description #1 148.00' 316 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 357 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 0 0 0 148.30 331 50 50 148.40 450 39 89 148.70 1,063 227 316 Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.26'12.0" Round Culvert Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 93HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.10' / 145.26' S= -0.0160 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=146.35' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.18 cfs @ 12.09 hrs HW=146.35' (Free Discharge) 3=Culvert (Passes 0.18 cfs of 2.61 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.18 cfs @ 2.05 fps) Summary for Pond 15P: RG15 Inflow Area = 0.065 ac, 51.91% Impervious, Inflow Depth > 2.63" for 10-Year event Inflow = 0.22 cfs @ 12.07 hrs, Volume= 0.014 af Outflow = 0.21 cfs @ 12.10 hrs, Volume= 0.014 af, Atten= 4%, Lag= 1.3 min Discarded = 0.00 cfs @ 12.10 hrs, Volume= 0.002 af Primary = 0.21 cfs @ 12.10 hrs, Volume= 0.013 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.42' @ 12.10 hrs Surf.Area= 68 sf Storage= 13 cf Flood Elev= 148.70' Surf.Area= 880 sf Storage= 337 cf Plug-Flow detention time= 1.7 min calculated for 0.014 af (100% of inflow) Center-of-Mass det. time= 1.2 min ( 787.9 - 786.7 ) Volume Invert Avail.Storage Storage Description #1 147.80' 296 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 337 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.80 0 0 0 148.00 173 17 17 148.30 300 71 88 148.40 354 33 121 148.70 812 175 296 Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 94HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.20'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.20' / 144.84' S= 0.0360 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.10 hrs HW=146.42' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.21 cfs @ 12.10 hrs HW=146.42' (Free Discharge) 3=Culvert (Passes 0.21 cfs of 3.21 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.21 cfs @ 2.42 fps) Summary for Pond 16P: INF-10+11 Inflow Area = 0.368 ac, 90.56% Impervious, Inflow Depth > 4.10" for 10-Year event Inflow = 1.77 cfs @ 12.07 hrs, Volume= 0.126 af Outflow = 1.77 cfs @ 12.07 hrs, Volume= 0.115 af, Atten= 0%, Lag= 0.0 min Discarded = 0.04 cfs @ 12.07 hrs, Volume= 0.036 af Primary = 1.74 cfs @ 12.07 hrs, Volume= 0.079 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.30' @ 12.07 hrs Surf.Area= 909 sf Storage= 494 cf Flood Elev= 149.00' Surf.Area= 11,205 sf Storage= 3,082 cf Plug-Flow detention time= 47.7 min calculated for 0.115 af (92% of inflow) Center-of-Mass det. time= 18.1 min ( 757.6 - 739.6 ) Volume Invert Avail.Storage Storage Description #1 146.00' 271 cf Stone Bedding (Prismatic) Listed below (Recalc) 897 cf Overall - 219 cf Embedded = 678 cf x 40.0% Voids #2 146.08' 219 cf 10.0" Round Pipe Storage Inside #1 L= 402.0' #3 147.00' 2,592 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,082 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 897 0 0 147.00 897 897 897 Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 95HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 5,154 1,290 1,296 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.70'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.44' S= 0.0081 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.80'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0194 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.04 cfs @ 12.07 hrs HW=147.30' (Free Discharge) 5=Exfiltration ( Controls 0.04 cfs) Primary OutFlow Max=1.73 cfs @ 12.07 hrs HW=147.30' (Free Discharge) 2=Culvert (Passes 0.87 cfs of 5.48 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.87 cfs @ 1.46 fps) 4=Culvert (Passes 0.87 cfs of 5.35 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.87 cfs @ 1.46 fps) Summary for Pond 17P: INF-6+8 Inflow Area = 0.293 ac, 88.50% Impervious, Inflow Depth > 3.96" for 10-Year event Inflow = 1.39 cfs @ 12.07 hrs, Volume= 0.097 af Outflow = 1.38 cfs @ 12.07 hrs, Volume= 0.090 af, Atten= 0%, Lag= 0.2 min Discarded = 0.02 cfs @ 12.07 hrs, Volume= 0.023 af Primary = 1.36 cfs @ 12.07 hrs, Volume= 0.067 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.07' @ 12.07 hrs Surf.Area= 628 sf Storage= 335 cf Flood Elev= 148.90' Surf.Area= 14,038 sf Storage= 3,704 cf Plug-Flow detention time= 38.4 min calculated for 0.090 af (93% of inflow) Center-of-Mass det. time= 14.2 min ( 760.6 - 746.4 ) Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 96HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Volume Invert Avail.Storage Storage Description #1 146.00' 188 cf Stone Bedding (Prismatic) Listed below (Recalc) 616 cf Overall - 146 cf Embedded = 470 cf x 40.0% Voids #2 146.08' 146 cf 10.0" Round Pipe Storage Inside #1 L= 267.0' #3 147.00' 3,371 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,704 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 616 0 0 147.00 616 616 616 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 6,711 1,679 1,685 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.80'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.32' S= 0.0155 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.50'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.15' S= 0.0113 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.02 cfs @ 12.07 hrs HW=147.07' (Free Discharge) 5=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=1.36 cfs @ 12.07 hrs HW=147.07' (Free Discharge) 2=Culvert (Passes 0.00 cfs of 5.03 cfs potential flow) 1=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs) 4=Culvert (Passes 1.36 cfs of 5.44 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 1.36 cfs @ 1.70 fps) Summary for Pond 18P: INF-5+7 Inflow Area = 0.214 ac, 91.42% Impervious, Inflow Depth > 4.12" for 10-Year event Inflow = 1.04 cfs @ 12.07 hrs, Volume= 0.073 af Outflow = 1.04 cfs @ 12.07 hrs, Volume= 0.067 af, Atten= 0%, Lag= 0.0 min Discarded = 0.03 cfs @ 12.07 hrs, Volume= 0.027 af Primary = 1.01 cfs @ 12.07 hrs, Volume= 0.040 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 10-Year Rainfall=4.91"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 97HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev= 146.98' @ 12.07 hrs Surf.Area= 664 sf Storage= 358 cf Flood Elev= 148.90' Surf.Area= 5,822 sf Storage= 1,665 cf Plug-Flow detention time= 55.7 min calculated for 0.067 af (91% of inflow) Center-of-Mass det. time= 25.2 min ( 764.6 - 739.5 ) Volume Invert Avail.Storage Storage Description #1 145.60' 199 cf Stone Bedding (Prismatic) Listed below (Recalc) 652 cf Overall - 154 cf Embedded = 498 cf x 40.0% Voids #2 145.68' 154 cf 10.0" Round Pipe Storage Inside #1 L= 282.0' #3 146.60' 1,312 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 1,665 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 145.60 652 0 0 146.60 652 652 652 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.60 6 0 0 148.00 6 8 8 148.50 2,585 648 656 Device Routing Invert Outlet Devices #1 Device 2 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.60'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.60' / 144.32' S= 0.0097 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.90'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.70'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.15' S= 0.0190 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 145.60'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.03 cfs @ 12.07 hrs HW=146.98' (Free Discharge) 5=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=1.00 cfs @ 12.07 hrs HW=146.98' (Free Discharge) 2=Culvert (Passes 0.77 cfs of 5.19 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.77 cfs @ 1.40 fps) 4=Culvert (Passes 0.24 cfs of 5.05 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.24 cfs @ 0.95 fps) Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 98HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Time span=1.00-20.00 hrs, dt=0.01 hrs, 1901 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Runoff Area=8,350 sf 98.42% Impervious Runoff Depth>5.44"Subcatchment 1S: A1 Tc=5.0 min CN=97 Runoff=1.17 cfs 0.087 af Runoff Area=4,496 sf 92.70% Impervious Runoff Depth>5.21"Subcatchment 2S: A2 Tc=5.0 min CN=95 Runoff=0.62 cfs 0.045 af Runoff Area=6,870 sf 97.82% Impervious Runoff Depth>5.44"Subcatchment 3S: A3 Tc=5.0 min CN=97 Runoff=0.97 cfs 0.071 af Runoff Area=8,648 sf 82.34% Impervious Runoff Depth>4.76"Subcatchment 4S: A4 Tc=5.0 min CN=91 Runoff=1.14 cfs 0.079 af Runoff Area=25,964 sf 100.00% Impervious Runoff Depth>5.55"Subcatchment 5S: B2 Tc=5.0 min CN=98 Runoff=3.67 cfs 0.276 af Runoff Area=7,072 sf 0.00% Impervious Runoff Depth>1.87"Subcatchment 6S: POND Tc=0.0 min CN=61 Runoff=0.45 cfs 0.025 af Runoff Area=57,882 sf 0.00% Impervious Runoff Depth>4.76"Subcatchment 7S: PRE REAR Tc=5.0 min CN=91 Runoff=7.65 cfs 0.527 af Runoff Area=5,095 sf 91.89% Impervious Runoff Depth>5.21"Subcatchment 8S: A5 Tc=5.0 min CN=95 Runoff=0.71 cfs 0.051 af Runoff Area=6,947 sf 89.75% Impervious Runoff Depth>5.09"Subcatchment 9S: A6 Tc=5.0 min CN=94 Runoff=0.95 cfs 0.068 af Runoff Area=4,230 sf 90.85% Impervious Runoff Depth>5.21"Subcatchment 10S: A7 Tc=5.0 min CN=95 Runoff=0.59 cfs 0.042 af Runoff Area=5,823 sf 87.02% Impervious Runoff Depth>4.98"Subcatchment 11S: A8 Tc=5.0 min CN=93 Runoff=0.79 cfs 0.055 af Runoff Area=11,231 sf 77.08% Impervious Runoff Depth>4.65"Subcatchment 12S: A9 Tc=5.0 min CN=90 Runoff=1.46 cfs 0.100 af Runoff Area=9,635 sf 93.98% Impervious Runoff Depth>5.32"Subcatchment 13S: A10 Tc=5.0 min CN=96 Runoff=1.35 cfs 0.098 af Runoff Area=6,395 sf 85.41% Impervious Runoff Depth>4.98"Subcatchment 14S: A11 Tc=5.0 min CN=93 Runoff=0.87 cfs 0.061 af Runoff Area=9,957 sf 48.28% Impervious Runoff Depth>3.50"Subcatchment 15S: A12 Tc=5.0 min CN=79 Runoff=1.03 cfs 0.067 af Runoff Area=3,453 sf 73.59% Impervious Runoff Depth>4.43"Subcatchment 16S: A13 Tc=5.0 min CN=88 Runoff=0.44 cfs 0.029 af Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 99HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Runoff Area=2,168 sf 59.73% Impervious Runoff Depth>3.90"Subcatchment 17S: A14 Tc=5.0 min CN=83 Runoff=0.25 cfs 0.016 af Runoff Area=2,826 sf 51.91% Impervious Runoff Depth>3.60"Subcatchment 18S: A15 Tc=5.0 min CN=80 Runoff=0.30 cfs 0.019 af Runoff Area=6,971 sf 100.00% Impervious Runoff Depth>5.55"Subcatchment 19S: B1 Tc=5.0 min CN=98 Runoff=0.98 cfs 0.074 af Runoff Area=71,761 sf 44.08% Impervious Runoff Depth>4.54"Subcatchment 20S: PRE FRONT Tc=5.0 min CN=89 Runoff=9.20 cfs 0.623 af Peak Elev=145.44' Inflow=1.17 cfs 0.087 afPond 1C: CB1 12.0" Round Culvert n=0.012 L=124.0' S=0.0050 '/' Outflow=1.17 cfs 0.087 af Peak Elev=145.36' Inflow=5.46 cfs 0.408 afPond 1D: DMH1 18.0" Round Culvert n=0.012 L=58.0' S=0.0050 '/' Outflow=5.46 cfs 0.408 af Peak Elev=146.82' Storage=10,511 cf Inflow=7.88 cfs 0.583 afPond 1P: POST REAR Discarded=0.13 cfs 0.118 af Primary=5.92 cfs 0.256 af Outflow=6.05 cfs 0.374 af Peak Elev=145.40' Inflow=0.62 cfs 0.045 afPond 2C: CB2 12.0" Round Culvert n=0.012 L=8.0' S=0.0437 '/' Outflow=0.62 cfs 0.045 af Peak Elev=145.17' Inflow=6.43 cfs 0.479 afPond 2D: DMH2 18.0" Round Culvert n=0.012 L=50.0' S=0.0050 '/' Outflow=6.43 cfs 0.479 af Peak Elev=147.14' Storage=8,038 cf Inflow=8.17 cfs 0.552 afPond 2P: POST FRONT Outflow=5.41 cfs 0.515 af Peak Elev=145.36' Inflow=0.97 cfs 0.071 afPond 3C: CB3 12.0" Round Culvert n=0.012 L=13.0' S=0.0115 '/' Outflow=0.97 cfs 0.071 af Peak Elev=145.02' Inflow=7.57 cfs 0.558 afPond 3D: DMH3 18.0" Round Culvert n=0.012 L=54.0' S=0.0056 '/' Outflow=7.57 cfs 0.558 af Peak Elev=145.40' Inflow=1.14 cfs 0.079 afPond 4C: CB4 12.0" Round Culvert n=0.012 L=8.0' S=0.0188 '/' Outflow=1.14 cfs 0.079 af Peak Elev=148.00' Storage=484 cf Inflow=1.46 cfs 0.100 afPond 9P: RG9 Discarded=0.03 cfs 0.004 af Primary=0.63 cfs 0.096 af Outflow=0.65 cfs 0.100 af Peak Elev=147.84' Storage=246 cf Inflow=1.03 cfs 0.067 afPond 12P: RG12 Discarded=0.03 cfs 0.003 af Primary=0.54 cfs 0.064 af Outflow=0.58 cfs 0.067 af Peak Elev=147.18' Storage=21 cf Inflow=0.44 cfs 0.029 afPond 13P: RG13 Discarded=0.00 cfs 0.001 af Primary=0.42 cfs 0.028 af Outflow=0.42 cfs 0.029 af Peak Elev=146.48' Storage=16 cf Inflow=0.25 cfs 0.016 afPond 14P: RG14 Discarded=0.00 cfs 0.002 af Primary=0.23 cfs 0.014 af Outflow=0.24 cfs 0.016 af Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 100HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev=146.62' Storage=21 cf Inflow=0.30 cfs 0.019 afPond 15P: RG15 Discarded=0.00 cfs 0.002 af Primary=0.28 cfs 0.018 af Outflow=0.28 cfs 0.019 af Peak Elev=147.33' Storage=494 cf Inflow=2.21 cfs 0.159 afPond 16P: INF-10+11 Discarded=0.04 cfs 0.039 af Primary=2.18 cfs 0.109 af Outflow=2.21 cfs 0.148 af Peak Elev=147.12' Storage=335 cf Inflow=1.74 cfs 0.123 afPond 17P: INF-6+8 Discarded=0.02 cfs 0.025 af Primary=1.73 cfs 0.092 af Outflow=1.75 cfs 0.117 af Peak Elev=147.01' Storage=358 cf Inflow=1.29 cfs 0.093 afPond 18P: INF-5+7 Discarded=0.03 cfs 0.029 af Primary=1.26 cfs 0.056 af Outflow=1.29 cfs 0.086 af Total Runoff Area = 6.101 ac Runoff Volume = 2.413 af Average Runoff Depth = 4.75" 45.85% Pervious = 2.798 ac 54.15% Impervious = 3.304 ac Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 101HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: A1 Runoff = 1.17 cfs @ 12.07 hrs, Volume= 0.087 af, Depth> 5.44" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 8,218 98 Paved parking, HSG B 132 61 >75% Grass cover, Good, HSG B 8,350 97 Weighted Average 132 1.58% Pervious Area 8,218 98.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: A2 Runoff = 0.62 cfs @ 12.07 hrs, Volume= 0.045 af, Depth> 5.21" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 4,168 98 Paved parking, HSG B 328 61 >75% Grass cover, Good, HSG B 4,496 95 Weighted Average 328 7.30% Pervious Area 4,168 92.70% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 3S: A3 Runoff = 0.97 cfs @ 12.07 hrs, Volume= 0.071 af, Depth> 5.44" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 6,720 98 Paved parking, HSG B 150 61 >75% Grass cover, Good, HSG B 6,870 97 Weighted Average 150 2.18% Pervious Area 6,720 97.82% Impervious Area Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 102HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 4S: A4 Runoff = 1.14 cfs @ 12.07 hrs, Volume= 0.079 af, Depth> 4.76" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 7,121 98 Paved parking, HSG B 1,527 61 >75% Grass cover, Good, HSG B 8,648 91 Weighted Average 1,527 17.66% Pervious Area 7,121 82.34% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: B2 Runoff = 3.67 cfs @ 12.07 hrs, Volume= 0.276 af, Depth> 5.55" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 25,964 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 25,964 98 Weighted Average 25,964 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 6S: POND Runoff = 0.45 cfs @ 12.00 hrs, Volume= 0.025 af, Depth> 1.87" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 103HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 7,072 61 >75% Grass cover, Good, HSG B 7,072 100.00% Pervious Area Summary for Subcatchment 7S: PRE REAR Runoff = 7.65 cfs @ 12.07 hrs, Volume= 0.527 af, Depth> 4.76" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 9,064 67 Brush, Poor, HSG B 48,818 96 Gravel surface, HSG B 57,882 91 Weighted Average 57,882 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 8S: A5 Runoff = 0.71 cfs @ 12.07 hrs, Volume= 0.051 af, Depth> 5.21" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 4,682 98 Paved parking, HSG B 413 61 >75% Grass cover, Good, HSG B 5,095 95 Weighted Average 413 8.11% Pervious Area 4,682 91.89% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: A6 Runoff = 0.95 cfs @ 12.07 hrs, Volume= 0.068 af, Depth> 5.09" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 104HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 6,235 98 Paved parking, HSG B 712 61 >75% Grass cover, Good, HSG B 6,947 94 Weighted Average 712 10.25% Pervious Area 6,235 89.75% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 10S: A7 Runoff = 0.59 cfs @ 12.07 hrs, Volume= 0.042 af, Depth> 5.21" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 3,843 98 Paved parking, HSG B 387 61 >75% Grass cover, Good, HSG B 4,230 95 Weighted Average 387 9.15% Pervious Area 3,843 90.85% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 11S: A8 Runoff = 0.79 cfs @ 12.07 hrs, Volume= 0.055 af, Depth> 4.98" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 5,067 98 Paved parking, HSG B 756 61 >75% Grass cover, Good, HSG B 5,823 93 Weighted Average 756 12.98% Pervious Area 5,067 87.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 105HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 12S: A9 Runoff = 1.46 cfs @ 12.07 hrs, Volume= 0.100 af, Depth> 4.65" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 8,657 98 Paved parking, HSG B 2,574 61 >75% Grass cover, Good, HSG B 11,231 90 Weighted Average 2,574 22.92% Pervious Area 8,657 77.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 13S: A10 Runoff = 1.35 cfs @ 12.07 hrs, Volume= 0.098 af, Depth> 5.32" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 9,055 98 Paved parking, HSG B 580 61 >75% Grass cover, Good, HSG B 9,635 96 Weighted Average 580 6.02% Pervious Area 9,055 93.98% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 14S: A11 Runoff = 0.87 cfs @ 12.07 hrs, Volume= 0.061 af, Depth> 4.98" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 5,462 98 Paved parking, HSG B 933 61 >75% Grass cover, Good, HSG B 6,395 93 Weighted Average 933 14.59% Pervious Area 5,462 85.41% Impervious Area Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 106HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 15S: A12 Runoff = 1.03 cfs @ 12.07 hrs, Volume= 0.067 af, Depth> 3.50" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 4,807 98 Paved parking, HSG B 5,150 61 >75% Grass cover, Good, HSG B 9,957 79 Weighted Average 5,150 51.72% Pervious Area 4,807 48.28% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 16S: A13 Runoff = 0.44 cfs @ 12.07 hrs, Volume= 0.029 af, Depth> 4.43" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 2,541 98 Paved parking, HSG B 912 61 >75% Grass cover, Good, HSG B 3,453 88 Weighted Average 912 26.41% Pervious Area 2,541 73.59% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 17S: A14 Runoff = 0.25 cfs @ 12.07 hrs, Volume= 0.016 af, Depth> 3.90" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 107HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 1,295 98 Paved parking, HSG B 873 61 >75% Grass cover, Good, HSG B 2,168 83 Weighted Average 873 40.27% Pervious Area 1,295 59.73% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 18S: A15 Runoff = 0.30 cfs @ 12.07 hrs, Volume= 0.019 af, Depth> 3.60" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 1,467 98 Paved parking, HSG B 1,359 61 >75% Grass cover, Good, HSG B 2,826 80 Weighted Average 1,359 48.09% Pervious Area 1,467 51.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 19S: B1 Runoff = 0.98 cfs @ 12.07 hrs, Volume= 0.074 af, Depth> 5.55" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 6,971 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 6,971 98 Weighted Average 6,971 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 108HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 20S: PRE FRONT Runoff = 9.20 cfs @ 12.07 hrs, Volume= 0.623 af, Depth> 4.54" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06" Area (sf) CN Description 24,527 96 Gravel surface, HSG B 15,601 61 >75% Grass cover, Good, HSG B 31,633 98 Paved parking, HSG B 71,761 89 Weighted Average 40,128 55.92% Pervious Area 31,633 44.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Pond 1C: CB1 Inflow Area = 0.192 ac, 98.42% Impervious, Inflow Depth > 5.44" for 25-Year event Inflow = 1.17 cfs @ 12.07 hrs, Volume= 0.087 af Outflow = 1.17 cfs @ 12.07 hrs, Volume= 0.087 af, Atten= 0%, Lag= 0.0 min Primary = 1.17 cfs @ 12.07 hrs, Volume= 0.087 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.44' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 124.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=1.17 cfs @ 12.07 hrs HW=145.44' (Free Discharge) 1=Culvert (Barrel Controls 1.17 cfs @ 3.18 fps) Summary for Pond 1D: DMH1 Inflow Area = 0.891 ac, 98.81% Impervious, Inflow Depth > 5.49" for 25-Year event Inflow = 5.46 cfs @ 12.07 hrs, Volume= 0.408 af Outflow = 5.46 cfs @ 12.07 hrs, Volume= 0.408 af, Atten= 0%, Lag= 0.0 min Primary = 5.46 cfs @ 12.07 hrs, Volume= 0.408 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.36' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.00'18.0" Round 18" CPEP Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 109HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 58.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.00' / 143.71' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=5.46 cfs @ 12.07 hrs HW=145.36' (Free Discharge) 1=18" CPEP (Barrel Controls 5.46 cfs @ 4.27 fps) Summary for Pond 1P: POST REAR Inflow Area = 1.410 ac, 85.00% Impervious, Inflow Depth > 4.96" for 25-Year event Inflow = 7.88 cfs @ 12.07 hrs, Volume= 0.583 af Outflow = 6.05 cfs @ 12.13 hrs, Volume= 0.374 af, Atten= 23%, Lag= 3.8 min Discarded = 0.13 cfs @ 12.13 hrs, Volume= 0.118 af Primary = 5.92 cfs @ 12.13 hrs, Volume= 0.256 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.82' @ 12.13 hrs Surf.Area= 4,414 sf Storage= 10,511 cf Plug-Flow detention time= 140.4 min calculated for 0.374 af (64% of inflow) Center-of-Mass det. time= 59.9 min ( 788.6 - 728.7 ) Volume Invert Avail.Storage Storage Description #1 143.00' 11,310 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 143.00 1,320 0 0 144.00 1,986 1,653 1,653 145.00 2,752 2,369 4,022 146.00 3,619 3,186 7,208 147.00 4,586 4,103 11,310 Device Routing Invert Outlet Devices #1 Discarded 143.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 135.00' #2 Primary 146.50'12.0' long x 16.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Discarded OutFlow Max=0.13 cfs @ 12.13 hrs HW=146.82' (Free Discharge) 1=Exfiltration ( Controls 0.13 cfs) Primary OutFlow Max=5.91 cfs @ 12.13 hrs HW=146.82' (Free Discharge) 2=Broad-Crested Rectangular Weir (Weir Controls 5.91 cfs @ 1.53 fps) Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 110HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 2C: CB2 Inflow Area = 0.103 ac, 92.70% Impervious, Inflow Depth > 5.21" for 25-Year event Inflow = 0.62 cfs @ 12.07 hrs, Volume= 0.045 af Outflow = 0.62 cfs @ 12.07 hrs, Volume= 0.045 af, Atten= 0%, Lag= 0.0 min Primary = 0.62 cfs @ 12.07 hrs, Volume= 0.045 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.40' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 145.00'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.00' / 144.65' S= 0.0437 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.62 cfs @ 12.07 hrs HW=145.40' (Free Discharge) 1=Culvert (Inlet Controls 0.62 cfs @ 2.14 fps) Summary for Pond 2D: DMH2 Inflow Area = 1.049 ac, 98.66% Impervious, Inflow Depth > 5.48" for 25-Year event Inflow = 6.43 cfs @ 12.07 hrs, Volume= 0.479 af Outflow = 6.43 cfs @ 12.07 hrs, Volume= 0.479 af, Atten= 0%, Lag= 0.0 min Primary = 6.43 cfs @ 12.07 hrs, Volume= 0.479 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.17' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.63'18.0" Round 18" CPEP L= 50.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.63' / 143.38' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=6.43 cfs @ 12.07 hrs HW=145.17' (Free Discharge) 1=18" CPEP (Barrel Controls 6.43 cfs @ 4.41 fps) Summary for Pond 2P: POST FRONT Inflow Area = 1.716 ac, 80.40% Impervious, Inflow Depth > 3.86" for 25-Year event Inflow = 8.17 cfs @ 12.07 hrs, Volume= 0.552 af Outflow = 5.41 cfs @ 12.17 hrs, Volume= 0.515 af, Atten= 34%, Lag= 6.1 min Primary = 5.41 cfs @ 12.17 hrs, Volume= 0.515 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Starting Elev= 144.27' Surf.Area= 2,195 sf Storage= 940 cf Peak Elev= 147.14' @ 12.17 hrs Surf.Area= 138 sf Storage= 8,038 cf (7,097 cf above start) Flood Elev= 148.20' Surf.Area= 508 sf Storage= 8,258 cf (7,318 cf above start) Plug-Flow detention time= 74.3 min calculated for 0.493 af (89% of inflow) Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 111HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Center-of-Mass det. time= 40.0 min ( 792.0 - 752.0 ) Volume Invert Avail.Storage Storage Description #1 143.90' 509 cf 4.00'D x 4.50'H DMH x 9 #2 143.86' 226 cf 30.0" Round 30" Flat CPEP (10-11) L= 46.0' S= 0.0070 '/' #3 143.74' 324 cf 30.0" Round 30" Flat CPEP (11-12) L= 66.0' S= 0.0003 '/' #4 143.78' 275 cf 30.0" Round 30" Flat CPEP (12-Out) L= 56.0' S= 0.0016 '/' #5 143.88' 1,924 cf 30.0" Round 30" Flat CPEP (9-Out) x 4 L= 98.0' S= 0.0030 '/' #6 143.39' 1,031 cf 30.0" Round 30" Flat CPEP (6-9) x 3 L= 70.0' S= 0.0007 '/' #7 143.59' 260 cf 30.0" Round 30" Flat CPEP (8-9) L= 53.0' S= 0.0008 '/' #8 143.38' 476 cf 30.0" Round 30" Flat CPEP (7-8) L= 97.0' S= 0.0008 '/' #9 143.39' 285 cf 30.0" Round 30" Flat CPEP (5-6) L= 58.0' S= 0.0007 '/' #10 143.50' 422 cf 30.0" Round 30" Flat CPEP (4-5) L= 86.0' S= 0.0003 '/' #11 148.00' 333 cf Custom Stage Data (Prismatic) Listed below (Recalc) #12 144.27' 2,376 cf 30.0" Round Prop. 30" Flat CPEP L= 484.0' #13 144.27' 113 cf 4.00'D x 4.50'H Prop. DMH x 2 8,554 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 370 0 0 148.90 370 333 333 Device Routing Invert Outlet Devices #1 Device 3 144.27'10.0" Vert. 10" Orifice C= 0.600 #2 Device 3 146.85'36.0" W x 4.0" H Vert. 4"x36" Weir/Orifice C= 0.600 #3 Primary 144.65'12.0" Round 12" Culvert L= 16.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.65' / 143.50' S= 0.0719 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Primary 148.00'37.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=5.30 cfs @ 12.17 hrs HW=147.11' (Free Discharge) 3=12" Culvert (Inlet Controls 5.30 cfs @ 6.75 fps) 1=10" Orifice (Passes < 4.09 cfs potential flow) 2=4"x36" Weir/Orifice (Passes < 1.30 cfs potential flow) 4=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 112HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 3C: CB3 Inflow Area = 0.158 ac, 97.82% Impervious, Inflow Depth > 5.44" for 25-Year event Inflow = 0.97 cfs @ 12.07 hrs, Volume= 0.071 af Outflow = 0.97 cfs @ 12.07 hrs, Volume= 0.071 af, Atten= 0%, Lag= 0.0 min Primary = 0.97 cfs @ 12.07 hrs, Volume= 0.071 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.36' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 13.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0115 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.97 cfs @ 12.07 hrs HW=145.36' (Free Discharge) 1=Culvert (Barrel Controls 0.97 cfs @ 3.12 fps) Summary for Pond 3D: DMH3 Inflow Area = 1.247 ac, 96.07% Impervious, Inflow Depth > 5.37" for 25-Year event Inflow = 7.57 cfs @ 12.07 hrs, Volume= 0.558 af Outflow = 7.57 cfs @ 12.07 hrs, Volume= 0.558 af, Atten= 0%, Lag= 0.0 min Primary = 7.57 cfs @ 12.07 hrs, Volume= 0.558 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.02' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.30'18.0" Round Culvert L= 54.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.30' / 143.00' S= 0.0056 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=7.57 cfs @ 12.07 hrs HW=145.02' (Free Discharge) 1=Culvert (Barrel Controls 7.57 cfs @ 4.68 fps) Summary for Pond 4C: CB4 Inflow Area = 0.199 ac, 82.34% Impervious, Inflow Depth > 4.76" for 25-Year event Inflow = 1.14 cfs @ 12.07 hrs, Volume= 0.079 af Outflow = 1.14 cfs @ 12.07 hrs, Volume= 0.079 af, Atten= 0%, Lag= 0.0 min Primary = 1.14 cfs @ 12.07 hrs, Volume= 0.079 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.40' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 113HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0188 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=1.14 cfs @ 12.07 hrs HW=145.40' (Free Discharge) 1=Culvert (Barrel Controls 1.14 cfs @ 3.34 fps) Summary for Pond 9P: RG9 Inflow Area = 0.258 ac, 77.08% Impervious, Inflow Depth > 4.65" for 25-Year event Inflow = 1.46 cfs @ 12.07 hrs, Volume= 0.100 af Outflow = 0.65 cfs @ 12.23 hrs, Volume= 0.100 af, Atten= 55%, Lag= 9.6 min Discarded = 0.03 cfs @ 12.23 hrs, Volume= 0.004 af Primary = 0.63 cfs @ 12.23 hrs, Volume= 0.096 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 148.00' @ 12.23 hrs Surf.Area= 920 sf Storage= 484 cf Flood Elev= 148.40' Surf.Area= 1,804 sf Storage= 1,004 cf Plug-Flow detention time= 4.0 min calculated for 0.100 af (100% of inflow) Center-of-Mass det. time= 3.7 min ( 757.6 - 753.9 ) Volume Invert Avail.Storage Storage Description #1 147.40' 963 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 145.60' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 145.60' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,004 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.40 632 0 0 148.00 853 445 445 148.40 1,736 518 963 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 145.60'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 34.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 143.94' S= 0.0165 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 145.60'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 114HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.03 cfs @ 12.23 hrs HW=148.00' (Free Discharge) 2=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=0.63 cfs @ 12.23 hrs HW=148.00' (Free Discharge) 3=Culvert (Passes 0.63 cfs of 6.55 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.63 cfs @ 7.19 fps) Summary for Pond 12P: RG12 Inflow Area = 0.229 ac, 48.28% Impervious, Inflow Depth > 3.50" for 25-Year event Inflow = 1.03 cfs @ 12.07 hrs, Volume= 0.067 af Outflow = 0.58 cfs @ 12.18 hrs, Volume= 0.067 af, Atten= 44%, Lag= 6.7 min Discarded = 0.03 cfs @ 12.18 hrs, Volume= 0.003 af Primary = 0.54 cfs @ 12.18 hrs, Volume= 0.064 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.84' @ 12.18 hrs Surf.Area= 1,271 sf Storage= 246 cf Flood Elev= 148.40' Surf.Area= 3,301 sf Storage= 1,481 cf Plug-Flow detention time= 2.6 min calculated for 0.067 af (100% of inflow) Center-of-Mass det. time= 2.3 min ( 783.8 - 781.5 ) Volume Invert Avail.Storage Storage Description #1 147.50' 1,440 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,481 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 1,764 441 441 148.40 3,233 999 1,440 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 19.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.09' S= 0.0216 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 115HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.03 cfs @ 12.18 hrs HW=147.84' (Free Discharge) 2=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=0.54 cfs @ 12.18 hrs HW=147.84' (Free Discharge) 3=Culvert (Passes 0.54 cfs of 6.37 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.54 cfs @ 6.23 fps) Summary for Pond 13P: RG13 Inflow Area = 0.079 ac, 73.59% Impervious, Inflow Depth > 4.43" for 25-Year event Inflow = 0.44 cfs @ 12.07 hrs, Volume= 0.029 af Outflow = 0.42 cfs @ 12.09 hrs, Volume= 0.029 af, Atten= 3%, Lag= 1.1 min Discarded = 0.00 cfs @ 12.09 hrs, Volume= 0.001 af Primary = 0.42 cfs @ 12.09 hrs, Volume= 0.028 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.18' @ 12.09 hrs Surf.Area= 36 sf Storage= 21 cf Flood Elev= 148.70' Surf.Area= 1,047 sf Storage= 282 cf Plug-Flow detention time= 0.9 min calculated for 0.029 af (100% of inflow) Center-of-Mass det. time= 0.6 min ( 760.6 - 759.9 ) Volume Invert Avail.Storage Storage Description #1 147.50' 261 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 13 cf 3.21'W x 11.33'L x 1.21'H Field A 44 cf Overall - 10 cf Embedded = 33 cf x 40.0% Voids #3A 146.00' 8 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf Row Length Adjustment= -10.00' x 0.81 sf x 1 rows 282 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 127 32 32 148.40 249 75 107 148.50 269 26 133 148.70 1,011 128 261 Device Routing Invert Outlet Devices #1 Device 3 148.30'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.10'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 116HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 145.10' / 144.84' S= 0.0260 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.09 hrs HW=147.18' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.42 cfs @ 12.09 hrs HW=147.18' (Free Discharge) 3=Culvert (Passes 0.42 cfs of 4.75 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.42 cfs @ 4.84 fps) Summary for Pond 14P: RG14 Inflow Area = 0.050 ac, 59.73% Impervious, Inflow Depth > 3.90" for 25-Year event Inflow = 0.25 cfs @ 12.07 hrs, Volume= 0.016 af Outflow = 0.24 cfs @ 12.10 hrs, Volume= 0.016 af, Atten= 4%, Lag= 1.4 min Discarded = 0.00 cfs @ 12.10 hrs, Volume= 0.002 af Primary = 0.23 cfs @ 12.10 hrs, Volume= 0.014 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.48' @ 12.10 hrs Surf.Area= 68 sf Storage= 16 cf Flood Elev= 148.70' Surf.Area= 1,131 sf Storage= 357 cf Plug-Flow detention time= 1.7 min calculated for 0.016 af (100% of inflow) Center-of-Mass det. time= 1.3 min ( 774.0 - 772.7 ) Volume Invert Avail.Storage Storage Description #1 148.00' 316 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 357 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 0 0 0 148.30 331 50 50 148.40 450 39 89 148.70 1,063 227 316 Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.26'12.0" Round Culvert Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 117HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.10' / 145.26' S= -0.0160 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.10 hrs HW=146.48' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.23 cfs @ 12.10 hrs HW=146.48' (Free Discharge) 3=Culvert (Passes 0.23 cfs of 2.92 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.23 cfs @ 2.69 fps) Summary for Pond 15P: RG15 Inflow Area = 0.065 ac, 51.91% Impervious, Inflow Depth > 3.60" for 25-Year event Inflow = 0.30 cfs @ 12.07 hrs, Volume= 0.019 af Outflow = 0.28 cfs @ 12.10 hrs, Volume= 0.019 af, Atten= 6%, Lag= 1.6 min Discarded = 0.00 cfs @ 12.10 hrs, Volume= 0.002 af Primary = 0.28 cfs @ 12.10 hrs, Volume= 0.018 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.62' @ 12.10 hrs Surf.Area= 68 sf Storage= 21 cf Flood Elev= 148.70' Surf.Area= 880 sf Storage= 337 cf Plug-Flow detention time= 1.6 min calculated for 0.019 af (100% of inflow) Center-of-Mass det. time= 1.2 min ( 780.6 - 779.4 ) Volume Invert Avail.Storage Storage Description #1 147.80' 296 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 337 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.80 0 0 0 148.00 173 17 17 148.30 300 71 88 148.40 354 33 121 148.70 812 175 296 Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 118HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.20'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.20' / 144.84' S= 0.0360 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.10 hrs HW=146.62' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.28 cfs @ 12.10 hrs HW=146.62' (Free Discharge) 3=Culvert (Passes 0.28 cfs of 3.62 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.28 cfs @ 3.23 fps) Summary for Pond 16P: INF-10+11 Inflow Area = 0.368 ac, 90.56% Impervious, Inflow Depth > 5.19" for 25-Year event Inflow = 2.21 cfs @ 12.07 hrs, Volume= 0.159 af Outflow = 2.21 cfs @ 12.07 hrs, Volume= 0.148 af, Atten= 0%, Lag= 0.0 min Discarded = 0.04 cfs @ 12.07 hrs, Volume= 0.039 af Primary = 2.18 cfs @ 12.07 hrs, Volume= 0.109 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.33' @ 12.07 hrs Surf.Area= 909 sf Storage= 494 cf Flood Elev= 149.00' Surf.Area= 11,205 sf Storage= 3,082 cf Plug-Flow detention time= 41.4 min calculated for 0.148 af (93% of inflow) Center-of-Mass det. time= 15.1 min ( 749.8 - 734.6 ) Volume Invert Avail.Storage Storage Description #1 146.00' 271 cf Stone Bedding (Prismatic) Listed below (Recalc) 897 cf Overall - 219 cf Embedded = 678 cf x 40.0% Voids #2 146.08' 219 cf 10.0" Round Pipe Storage Inside #1 L= 402.0' #3 147.00' 2,592 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,082 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 897 0 0 147.00 897 897 897 Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 119HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 5,154 1,290 1,296 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.70'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.44' S= 0.0081 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.80'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0194 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.04 cfs @ 12.07 hrs HW=147.33' (Free Discharge) 5=Exfiltration ( Controls 0.04 cfs) Primary OutFlow Max=2.17 cfs @ 12.07 hrs HW=147.33' (Free Discharge) 2=Culvert (Passes 1.09 cfs of 5.52 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 1.09 cfs @ 1.58 fps) 4=Culvert (Passes 1.09 cfs of 5.39 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 1.09 cfs @ 1.58 fps) Summary for Pond 17P: INF-6+8 Inflow Area = 0.293 ac, 88.50% Impervious, Inflow Depth > 5.04" for 25-Year event Inflow = 1.74 cfs @ 12.07 hrs, Volume= 0.123 af Outflow = 1.75 cfs @ 12.07 hrs, Volume= 0.117 af, Atten= 0%, Lag= 0.0 min Discarded = 0.02 cfs @ 12.07 hrs, Volume= 0.025 af Primary = 1.73 cfs @ 12.07 hrs, Volume= 0.092 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.12' @ 12.07 hrs Surf.Area= 628 sf Storage= 335 cf Flood Elev= 148.90' Surf.Area= 14,038 sf Storage= 3,704 cf Plug-Flow detention time= 33.5 min calculated for 0.117 af (95% of inflow) Center-of-Mass det. time= 13.3 min ( 754.2 - 740.9 ) Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 120HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Volume Invert Avail.Storage Storage Description #1 146.00' 188 cf Stone Bedding (Prismatic) Listed below (Recalc) 616 cf Overall - 146 cf Embedded = 470 cf x 40.0% Voids #2 146.08' 146 cf 10.0" Round Pipe Storage Inside #1 L= 267.0' #3 147.00' 3,371 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,704 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 616 0 0 147.00 616 616 616 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 6,711 1,679 1,685 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.80'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.32' S= 0.0155 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.50'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.15' S= 0.0113 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.02 cfs @ 12.07 hrs HW=147.12' (Free Discharge) 5=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=1.72 cfs @ 12.07 hrs HW=147.12' (Free Discharge) 2=Culvert (Passes 0.02 cfs of 5.10 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.02 cfs @ 0.40 fps) 4=Culvert (Passes 1.70 cfs of 5.50 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 1.70 cfs @ 1.84 fps) Summary for Pond 18P: INF-5+7 Inflow Area = 0.214 ac, 91.42% Impervious, Inflow Depth > 5.21" for 25-Year event Inflow = 1.29 cfs @ 12.07 hrs, Volume= 0.093 af Outflow = 1.29 cfs @ 12.07 hrs, Volume= 0.086 af, Atten= 0%, Lag= 0.0 min Discarded = 0.03 cfs @ 12.07 hrs, Volume= 0.029 af Primary = 1.26 cfs @ 12.07 hrs, Volume= 0.056 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 25-Year Rainfall=6.06"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 121HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev= 147.01' @ 12.07 hrs Surf.Area= 664 sf Storage= 358 cf Flood Elev= 148.90' Surf.Area= 5,822 sf Storage= 1,665 cf Plug-Flow detention time= 48.2 min calculated for 0.086 af (92% of inflow) Center-of-Mass det. time= 19.9 min ( 754.4 - 734.4 ) Volume Invert Avail.Storage Storage Description #1 145.60' 199 cf Stone Bedding (Prismatic) Listed below (Recalc) 652 cf Overall - 154 cf Embedded = 498 cf x 40.0% Voids #2 145.68' 154 cf 10.0" Round Pipe Storage Inside #1 L= 282.0' #3 146.60' 1,312 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 1,665 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 145.60 652 0 0 146.60 652 652 652 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.60 6 0 0 148.00 6 8 8 148.50 2,585 648 656 Device Routing Invert Outlet Devices #1 Device 2 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.60'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.60' / 144.32' S= 0.0097 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.90'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.70'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.15' S= 0.0190 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 145.60'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.03 cfs @ 12.07 hrs HW=147.01' (Free Discharge) 5=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=1.26 cfs @ 12.07 hrs HW=147.01' (Free Discharge) 2=Culvert (Passes 0.91 cfs of 5.22 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.91 cfs @ 1.49 fps) 4=Culvert (Passes 0.34 cfs of 5.08 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.34 cfs @ 1.07 fps) Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 122HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Time span=1.00-20.00 hrs, dt=0.01 hrs, 1901 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Runoff Area=8,350 sf 98.42% Impervious Runoff Depth>6.28"Subcatchment 1S: A1 Tc=5.0 min CN=97 Runoff=1.35 cfs 0.100 af Runoff Area=4,496 sf 92.70% Impervious Runoff Depth>6.04"Subcatchment 2S: A2 Tc=5.0 min CN=95 Runoff=0.72 cfs 0.052 af Runoff Area=6,870 sf 97.82% Impervious Runoff Depth>6.28"Subcatchment 3S: A3 Tc=5.0 min CN=97 Runoff=1.11 cfs 0.083 af Runoff Area=8,648 sf 82.34% Impervious Runoff Depth>5.58"Subcatchment 4S: A4 Tc=5.0 min CN=91 Runoff=1.33 cfs 0.092 af Runoff Area=25,964 sf 100.00% Impervious Runoff Depth>6.39"Subcatchment 5S: B2 Tc=5.0 min CN=98 Runoff=4.20 cfs 0.318 af Runoff Area=7,072 sf 0.00% Impervious Runoff Depth>2.45"Subcatchment 6S: POND Tc=0.0 min CN=61 Runoff=0.60 cfs 0.033 af Runoff Area=57,882 sf 0.00% Impervious Runoff Depth>5.58"Subcatchment 7S: PRE REAR Tc=5.0 min CN=91 Runoff=8.89 cfs 0.618 af Runoff Area=5,095 sf 91.89% Impervious Runoff Depth>6.04"Subcatchment 8S: A5 Tc=5.0 min CN=95 Runoff=0.81 cfs 0.059 af Runoff Area=6,947 sf 89.75% Impervious Runoff Depth>5.93"Subcatchment 9S: A6 Tc=5.0 min CN=94 Runoff=1.10 cfs 0.079 af Runoff Area=4,230 sf 90.85% Impervious Runoff Depth>6.04"Subcatchment 10S: A7 Tc=5.0 min CN=95 Runoff=0.67 cfs 0.049 af Runoff Area=5,823 sf 87.02% Impervious Runoff Depth>5.81"Subcatchment 11S: A8 Tc=5.0 min CN=93 Runoff=0.91 cfs 0.065 af Runoff Area=11,231 sf 77.08% Impervious Runoff Depth>5.47"Subcatchment 12S: A9 Tc=5.0 min CN=90 Runoff=1.70 cfs 0.117 af Runoff Area=9,635 sf 93.98% Impervious Runoff Depth>6.16"Subcatchment 13S: A10 Tc=5.0 min CN=96 Runoff=1.55 cfs 0.114 af Runoff Area=6,395 sf 85.41% Impervious Runoff Depth>5.81"Subcatchment 14S: A11 Tc=5.0 min CN=93 Runoff=1.00 cfs 0.071 af Runoff Area=9,957 sf 48.28% Impervious Runoff Depth>4.25"Subcatchment 15S: A12 Tc=5.0 min CN=79 Runoff=1.25 cfs 0.081 af Runoff Area=3,453 sf 73.59% Impervious Runoff Depth>5.24"Subcatchment 16S: A13 Tc=5.0 min CN=88 Runoff=0.51 cfs 0.035 af Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 123HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Runoff Area=2,168 sf 59.73% Impervious Runoff Depth>4.68"Subcatchment 17S: A14 Tc=5.0 min CN=83 Runoff=0.29 cfs 0.019 af Runoff Area=2,826 sf 51.91% Impervious Runoff Depth>4.36"Subcatchment 18S: A15 Tc=5.0 min CN=80 Runoff=0.36 cfs 0.024 af Runoff Area=6,971 sf 100.00% Impervious Runoff Depth>6.39"Subcatchment 19S: B1 Tc=5.0 min CN=98 Runoff=1.13 cfs 0.085 af Runoff Area=71,761 sf 44.08% Impervious Runoff Depth>5.35"Subcatchment 20S: PRE FRONT Tc=5.0 min CN=89 Runoff=10.75 cfs 0.735 af Peak Elev=145.49' Inflow=1.35 cfs 0.100 afPond 1C: CB1 12.0" Round Culvert n=0.012 L=124.0' S=0.0050 '/' Outflow=1.35 cfs 0.100 af Peak Elev=145.50' Inflow=6.27 cfs 0.470 afPond 1D: DMH1 18.0" Round Culvert n=0.012 L=58.0' S=0.0050 '/' Outflow=6.27 cfs 0.470 af Peak Elev=146.89' Storage=10,820 cf Inflow=9.10 cfs 0.678 afPond 1P: POST REAR Discarded=0.13 cfs 0.122 af Primary=7.95 cfs 0.346 af Outflow=8.09 cfs 0.468 af Peak Elev=145.43' Inflow=0.72 cfs 0.052 afPond 2C: CB2 12.0" Round Culvert n=0.012 L=8.0' S=0.0437 '/' Outflow=0.72 cfs 0.052 af Peak Elev=145.35' Inflow=7.38 cfs 0.552 afPond 2D: DMH2 18.0" Round Culvert n=0.012 L=50.0' S=0.0050 '/' Outflow=7.38 cfs 0.552 af Peak Elev=148.07' Storage=8,192 cf Inflow=9.31 cfs 0.663 afPond 2P: POST FRONT Outflow=8.21 cfs 0.625 af Peak Elev=145.40' Inflow=1.11 cfs 0.083 afPond 3C: CB3 12.0" Round Culvert n=0.012 L=13.0' S=0.0115 '/' Outflow=1.11 cfs 0.083 af Peak Elev=145.38' Inflow=8.70 cfs 0.645 afPond 3D: DMH3 18.0" Round Culvert n=0.012 L=54.0' S=0.0056 '/' Outflow=8.70 cfs 0.645 af Peak Elev=145.46' Inflow=1.33 cfs 0.092 afPond 4C: CB4 12.0" Round Culvert n=0.012 L=8.0' S=0.0188 '/' Outflow=1.33 cfs 0.092 af Peak Elev=148.07' Storage=550 cf Inflow=1.70 cfs 0.117 afPond 9P: RG9 Discarded=0.03 cfs 0.004 af Primary=1.11 cfs 0.113 af Outflow=1.14 cfs 0.117 af Peak Elev=147.94' Storage=375 cf Inflow=1.25 cfs 0.081 afPond 12P: RG12 Discarded=0.04 cfs 0.003 af Primary=0.56 cfs 0.077 af Outflow=0.60 cfs 0.081 af Peak Elev=147.59' Storage=23 cf Inflow=0.51 cfs 0.035 afPond 13P: RG13 Discarded=0.00 cfs 0.001 af Primary=0.50 cfs 0.033 af Outflow=0.50 cfs 0.035 af Peak Elev=146.60' Storage=20 cf Inflow=0.29 cfs 0.019 afPond 14P: RG14 Discarded=0.00 cfs 0.002 af Primary=0.28 cfs 0.018 af Outflow=0.28 cfs 0.019 af Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 124HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev=146.80' Storage=28 cf Inflow=0.36 cfs 0.024 afPond 15P: RG15 Discarded=0.00 cfs 0.002 af Primary=0.33 cfs 0.022 af Outflow=0.34 cfs 0.024 af Peak Elev=147.36' Storage=495 cf Inflow=2.55 cfs 0.185 afPond 16P: INF-10+11 Discarded=0.04 cfs 0.041 af Primary=2.51 cfs 0.133 af Outflow=2.55 cfs 0.173 af Peak Elev=147.14' Storage=335 cf Inflow=2.01 cfs 0.143 afPond 17P: INF-6+8 Discarded=0.02 cfs 0.026 af Primary=1.99 cfs 0.112 af Outflow=2.01 cfs 0.137 af Peak Elev=147.02' Storage=358 cf Inflow=1.49 cfs 0.108 afPond 18P: INF-5+7 Discarded=0.03 cfs 0.031 af Primary=1.46 cfs 0.069 af Outflow=1.49 cfs 0.100 af Total Runoff Area = 6.101 ac Runoff Volume = 2.828 af Average Runoff Depth = 5.56" 45.85% Pervious = 2.798 ac 54.15% Impervious = 3.304 ac Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 125HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: A1 Runoff = 1.35 cfs @ 12.07 hrs, Volume= 0.100 af, Depth> 6.28" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 8,218 98 Paved parking, HSG B 132 61 >75% Grass cover, Good, HSG B 8,350 97 Weighted Average 132 1.58% Pervious Area 8,218 98.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: A2 Runoff = 0.72 cfs @ 12.07 hrs, Volume= 0.052 af, Depth> 6.04" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 4,168 98 Paved parking, HSG B 328 61 >75% Grass cover, Good, HSG B 4,496 95 Weighted Average 328 7.30% Pervious Area 4,168 92.70% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 3S: A3 Runoff = 1.11 cfs @ 12.07 hrs, Volume= 0.083 af, Depth> 6.28" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 6,720 98 Paved parking, HSG B 150 61 >75% Grass cover, Good, HSG B 6,870 97 Weighted Average 150 2.18% Pervious Area 6,720 97.82% Impervious Area Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 126HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 4S: A4 Runoff = 1.33 cfs @ 12.07 hrs, Volume= 0.092 af, Depth> 5.58" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 7,121 98 Paved parking, HSG B 1,527 61 >75% Grass cover, Good, HSG B 8,648 91 Weighted Average 1,527 17.66% Pervious Area 7,121 82.34% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: B2 Runoff = 4.20 cfs @ 12.07 hrs, Volume= 0.318 af, Depth> 6.39" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 25,964 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 25,964 98 Weighted Average 25,964 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 6S: POND Runoff = 0.60 cfs @ 12.00 hrs, Volume= 0.033 af, Depth> 2.45" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 127HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 7,072 61 >75% Grass cover, Good, HSG B 7,072 100.00% Pervious Area Summary for Subcatchment 7S: PRE REAR Runoff = 8.89 cfs @ 12.07 hrs, Volume= 0.618 af, Depth> 5.58" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 9,064 67 Brush, Poor, HSG B 48,818 96 Gravel surface, HSG B 57,882 91 Weighted Average 57,882 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 8S: A5 Runoff = 0.81 cfs @ 12.07 hrs, Volume= 0.059 af, Depth> 6.04" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 4,682 98 Paved parking, HSG B 413 61 >75% Grass cover, Good, HSG B 5,095 95 Weighted Average 413 8.11% Pervious Area 4,682 91.89% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: A6 Runoff = 1.10 cfs @ 12.07 hrs, Volume= 0.079 af, Depth> 5.93" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 128HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 6,235 98 Paved parking, HSG B 712 61 >75% Grass cover, Good, HSG B 6,947 94 Weighted Average 712 10.25% Pervious Area 6,235 89.75% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 10S: A7 Runoff = 0.67 cfs @ 12.07 hrs, Volume= 0.049 af, Depth> 6.04" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 3,843 98 Paved parking, HSG B 387 61 >75% Grass cover, Good, HSG B 4,230 95 Weighted Average 387 9.15% Pervious Area 3,843 90.85% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 11S: A8 Runoff = 0.91 cfs @ 12.07 hrs, Volume= 0.065 af, Depth> 5.81" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 5,067 98 Paved parking, HSG B 756 61 >75% Grass cover, Good, HSG B 5,823 93 Weighted Average 756 12.98% Pervious Area 5,067 87.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 129HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 12S: A9 Runoff = 1.70 cfs @ 12.07 hrs, Volume= 0.117 af, Depth> 5.47" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 8,657 98 Paved parking, HSG B 2,574 61 >75% Grass cover, Good, HSG B 11,231 90 Weighted Average 2,574 22.92% Pervious Area 8,657 77.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 13S: A10 Runoff = 1.55 cfs @ 12.07 hrs, Volume= 0.114 af, Depth> 6.16" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 9,055 98 Paved parking, HSG B 580 61 >75% Grass cover, Good, HSG B 9,635 96 Weighted Average 580 6.02% Pervious Area 9,055 93.98% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 14S: A11 Runoff = 1.00 cfs @ 12.07 hrs, Volume= 0.071 af, Depth> 5.81" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 5,462 98 Paved parking, HSG B 933 61 >75% Grass cover, Good, HSG B 6,395 93 Weighted Average 933 14.59% Pervious Area 5,462 85.41% Impervious Area Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 130HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 15S: A12 Runoff = 1.25 cfs @ 12.07 hrs, Volume= 0.081 af, Depth> 4.25" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 4,807 98 Paved parking, HSG B 5,150 61 >75% Grass cover, Good, HSG B 9,957 79 Weighted Average 5,150 51.72% Pervious Area 4,807 48.28% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 16S: A13 Runoff = 0.51 cfs @ 12.07 hrs, Volume= 0.035 af, Depth> 5.24" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 2,541 98 Paved parking, HSG B 912 61 >75% Grass cover, Good, HSG B 3,453 88 Weighted Average 912 26.41% Pervious Area 2,541 73.59% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 17S: A14 Runoff = 0.29 cfs @ 12.07 hrs, Volume= 0.019 af, Depth> 4.68" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 131HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 1,295 98 Paved parking, HSG B 873 61 >75% Grass cover, Good, HSG B 2,168 83 Weighted Average 873 40.27% Pervious Area 1,295 59.73% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 18S: A15 Runoff = 0.36 cfs @ 12.07 hrs, Volume= 0.024 af, Depth> 4.36" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 1,467 98 Paved parking, HSG B 1,359 61 >75% Grass cover, Good, HSG B 2,826 80 Weighted Average 1,359 48.09% Pervious Area 1,467 51.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 19S: B1 Runoff = 1.13 cfs @ 12.07 hrs, Volume= 0.085 af, Depth> 6.39" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 6,971 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 6,971 98 Weighted Average 6,971 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 132HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 20S: PRE FRONT Runoff = 10.75 cfs @ 12.07 hrs, Volume= 0.735 af, Depth> 5.35" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94" Area (sf) CN Description 24,527 96 Gravel surface, HSG B 15,601 61 >75% Grass cover, Good, HSG B 31,633 98 Paved parking, HSG B 71,761 89 Weighted Average 40,128 55.92% Pervious Area 31,633 44.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Pond 1C: CB1 Inflow Area = 0.192 ac, 98.42% Impervious, Inflow Depth > 6.28" for 50-Year event Inflow = 1.35 cfs @ 12.07 hrs, Volume= 0.100 af Outflow = 1.35 cfs @ 12.07 hrs, Volume= 0.100 af, Atten= 0%, Lag= 0.0 min Primary = 1.35 cfs @ 12.07 hrs, Volume= 0.100 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.49' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 124.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=1.35 cfs @ 12.07 hrs HW=145.49' (Free Discharge) 1=Culvert (Barrel Controls 1.35 cfs @ 3.29 fps) Summary for Pond 1D: DMH1 Inflow Area = 0.891 ac, 98.81% Impervious, Inflow Depth > 6.33" for 50-Year event Inflow = 6.27 cfs @ 12.07 hrs, Volume= 0.470 af Outflow = 6.27 cfs @ 12.07 hrs, Volume= 0.470 af, Atten= 0%, Lag= 0.0 min Primary = 6.27 cfs @ 12.07 hrs, Volume= 0.470 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.50' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.00'18.0" Round 18" CPEP Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 133HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 58.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.00' / 143.71' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=6.27 cfs @ 12.07 hrs HW=145.50' (Free Discharge) 1=18" CPEP (Barrel Controls 6.27 cfs @ 4.41 fps) Summary for Pond 1P: POST REAR Inflow Area = 1.410 ac, 85.00% Impervious, Inflow Depth > 5.77" for 50-Year event Inflow = 9.10 cfs @ 12.07 hrs, Volume= 0.678 af Outflow = 8.09 cfs @ 12.11 hrs, Volume= 0.468 af, Atten= 11%, Lag= 2.4 min Discarded = 0.13 cfs @ 12.11 hrs, Volume= 0.122 af Primary = 7.95 cfs @ 12.11 hrs, Volume= 0.346 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.89' @ 12.11 hrs Surf.Area= 4,482 sf Storage= 10,820 cf Plug-Flow detention time= 131.1 min calculated for 0.468 af (69% of inflow) Center-of-Mass det. time= 57.2 min ( 784.0 - 726.8 ) Volume Invert Avail.Storage Storage Description #1 143.00' 11,310 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 143.00 1,320 0 0 144.00 1,986 1,653 1,653 145.00 2,752 2,369 4,022 146.00 3,619 3,186 7,208 147.00 4,586 4,103 11,310 Device Routing Invert Outlet Devices #1 Discarded 143.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 135.00' #2 Primary 146.50'12.0' long x 16.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Discarded OutFlow Max=0.13 cfs @ 12.11 hrs HW=146.89' (Free Discharge) 1=Exfiltration ( Controls 0.13 cfs) Primary OutFlow Max=7.94 cfs @ 12.11 hrs HW=146.89' (Free Discharge) 2=Broad-Crested Rectangular Weir (Weir Controls 7.94 cfs @ 1.69 fps) Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 134HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 2C: CB2 Inflow Area = 0.103 ac, 92.70% Impervious, Inflow Depth > 6.04" for 50-Year event Inflow = 0.72 cfs @ 12.07 hrs, Volume= 0.052 af Outflow = 0.72 cfs @ 12.07 hrs, Volume= 0.052 af, Atten= 0%, Lag= 0.0 min Primary = 0.72 cfs @ 12.07 hrs, Volume= 0.052 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.43' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 145.00'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.00' / 144.65' S= 0.0437 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.72 cfs @ 12.07 hrs HW=145.43' (Free Discharge) 1=Culvert (Inlet Controls 0.72 cfs @ 2.23 fps) Summary for Pond 2D: DMH2 Inflow Area = 1.049 ac, 98.66% Impervious, Inflow Depth > 6.32" for 50-Year event Inflow = 7.38 cfs @ 12.07 hrs, Volume= 0.552 af Outflow = 7.38 cfs @ 12.07 hrs, Volume= 0.552 af, Atten= 0%, Lag= 0.0 min Primary = 7.38 cfs @ 12.07 hrs, Volume= 0.552 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.35' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.63'18.0" Round 18" CPEP L= 50.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.63' / 143.38' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=7.38 cfs @ 12.07 hrs HW=145.35' (Free Discharge) 1=18" CPEP (Barrel Controls 7.38 cfs @ 4.56 fps) Summary for Pond 2P: POST FRONT Inflow Area = 1.716 ac, 80.40% Impervious, Inflow Depth > 4.64" for 50-Year event Inflow = 9.31 cfs @ 12.07 hrs, Volume= 0.663 af Outflow = 8.21 cfs @ 12.13 hrs, Volume= 0.625 af, Atten= 12%, Lag= 3.4 min Primary = 8.21 cfs @ 12.13 hrs, Volume= 0.625 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Starting Elev= 144.27' Surf.Area= 2,195 sf Storage= 940 cf Peak Elev= 148.07' @ 12.13 hrs Surf.Area= 508 sf Storage= 8,192 cf (7,252 cf above start) Flood Elev= 148.20' Surf.Area= 508 sf Storage= 8,258 cf (7,318 cf above start) Plug-Flow detention time= 69.0 min calculated for 0.603 af (91% of inflow) Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 135HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Center-of-Mass det. time= 37.2 min ( 787.7 - 750.5 ) Volume Invert Avail.Storage Storage Description #1 143.90' 509 cf 4.00'D x 4.50'H DMH x 9 #2 143.86' 226 cf 30.0" Round 30" Flat CPEP (10-11) L= 46.0' S= 0.0070 '/' #3 143.74' 324 cf 30.0" Round 30" Flat CPEP (11-12) L= 66.0' S= 0.0003 '/' #4 143.78' 275 cf 30.0" Round 30" Flat CPEP (12-Out) L= 56.0' S= 0.0016 '/' #5 143.88' 1,924 cf 30.0" Round 30" Flat CPEP (9-Out) x 4 L= 98.0' S= 0.0030 '/' #6 143.39' 1,031 cf 30.0" Round 30" Flat CPEP (6-9) x 3 L= 70.0' S= 0.0007 '/' #7 143.59' 260 cf 30.0" Round 30" Flat CPEP (8-9) L= 53.0' S= 0.0008 '/' #8 143.38' 476 cf 30.0" Round 30" Flat CPEP (7-8) L= 97.0' S= 0.0008 '/' #9 143.39' 285 cf 30.0" Round 30" Flat CPEP (5-6) L= 58.0' S= 0.0007 '/' #10 143.50' 422 cf 30.0" Round 30" Flat CPEP (4-5) L= 86.0' S= 0.0003 '/' #11 148.00' 333 cf Custom Stage Data (Prismatic) Listed below (Recalc) #12 144.27' 2,376 cf 30.0" Round Prop. 30" Flat CPEP L= 484.0' #13 144.27' 113 cf 4.00'D x 4.50'H Prop. DMH x 2 8,554 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 370 0 0 148.90 370 333 333 Device Routing Invert Outlet Devices #1 Device 3 144.27'10.0" Vert. 10" Orifice C= 0.600 #2 Device 3 146.85'36.0" W x 4.0" H Vert. 4"x36" Weir/Orifice C= 0.600 #3 Primary 144.65'12.0" Round 12" Culvert L= 16.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.65' / 143.50' S= 0.0719 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Primary 148.00'37.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=8.17 cfs @ 12.13 hrs HW=148.07' (Free Discharge) 3=12" Culvert (Inlet Controls 6.46 cfs @ 8.23 fps) 1=10" Orifice (Passes < 4.83 cfs potential flow) 2=4"x36" Weir/Orifice (Passes < 4.94 cfs potential flow) 4=Broad-Crested Rectangular Weir (Weir Controls 1.70 cfs @ 0.66 fps) Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 136HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 3C: CB3 Inflow Area = 0.158 ac, 97.82% Impervious, Inflow Depth > 6.28" for 50-Year event Inflow = 1.11 cfs @ 12.07 hrs, Volume= 0.083 af Outflow = 1.11 cfs @ 12.07 hrs, Volume= 0.083 af, Atten= 0%, Lag= 0.0 min Primary = 1.11 cfs @ 12.07 hrs, Volume= 0.083 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.40' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 13.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0115 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=1.11 cfs @ 12.07 hrs HW=145.40' (Free Discharge) 1=Culvert (Barrel Controls 1.11 cfs @ 3.21 fps) Summary for Pond 3D: DMH3 Inflow Area = 1.247 ac, 96.07% Impervious, Inflow Depth > 6.20" for 50-Year event Inflow = 8.70 cfs @ 12.07 hrs, Volume= 0.645 af Outflow = 8.70 cfs @ 12.07 hrs, Volume= 0.645 af, Atten= 0%, Lag= 0.0 min Primary = 8.70 cfs @ 12.07 hrs, Volume= 0.645 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.38' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.30'18.0" Round Culvert L= 54.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.30' / 143.00' S= 0.0056 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=8.70 cfs @ 12.07 hrs HW=145.38' (Free Discharge) 1=Culvert (Barrel Controls 8.70 cfs @ 4.92 fps) Summary for Pond 4C: CB4 Inflow Area = 0.199 ac, 82.34% Impervious, Inflow Depth > 5.58" for 50-Year event Inflow = 1.33 cfs @ 12.07 hrs, Volume= 0.092 af Outflow = 1.33 cfs @ 12.07 hrs, Volume= 0.092 af, Atten= 0%, Lag= 0.0 min Primary = 1.33 cfs @ 12.07 hrs, Volume= 0.092 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.46' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 137HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0188 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=1.33 cfs @ 12.07 hrs HW=145.46' (Free Discharge) 1=Culvert (Barrel Controls 1.33 cfs @ 3.44 fps) Summary for Pond 9P: RG9 Inflow Area = 0.258 ac, 77.08% Impervious, Inflow Depth > 5.47" for 50-Year event Inflow = 1.70 cfs @ 12.07 hrs, Volume= 0.117 af Outflow = 1.14 cfs @ 12.15 hrs, Volume= 0.117 af, Atten= 33%, Lag= 4.8 min Discarded = 0.03 cfs @ 12.15 hrs, Volume= 0.004 af Primary = 1.11 cfs @ 12.15 hrs, Volume= 0.113 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 148.07' @ 12.15 hrs Surf.Area= 1,072 sf Storage= 550 cf Flood Elev= 148.40' Surf.Area= 1,804 sf Storage= 1,004 cf Plug-Flow detention time= 4.1 min calculated for 0.117 af (100% of inflow) Center-of-Mass det. time= 3.9 min ( 753.9 - 750.0 ) Volume Invert Avail.Storage Storage Description #1 147.40' 963 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 145.60' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 145.60' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,004 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.40 632 0 0 148.00 853 445 445 148.40 1,736 518 963 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 145.60'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 34.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 143.94' S= 0.0165 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 145.60'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 138HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.03 cfs @ 12.15 hrs HW=148.07' (Free Discharge) 2=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=1.10 cfs @ 12.15 hrs HW=148.07' (Free Discharge) 3=Culvert (Passes 1.10 cfs of 6.62 cfs potential flow) 1=CB Inlet (Weir Controls 0.47 cfs @ 0.85 fps) 4=Underdrain (Orifice Controls 0.64 cfs @ 7.30 fps) Summary for Pond 12P: RG12 Inflow Area = 0.229 ac, 48.28% Impervious, Inflow Depth > 4.25" for 50-Year event Inflow = 1.25 cfs @ 12.07 hrs, Volume= 0.081 af Outflow = 0.60 cfs @ 12.22 hrs, Volume= 0.081 af, Atten= 52%, Lag= 8.8 min Discarded = 0.04 cfs @ 12.22 hrs, Volume= 0.003 af Primary = 0.56 cfs @ 12.22 hrs, Volume= 0.077 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.94' @ 12.22 hrs Surf.Area= 1,603 sf Storage= 375 cf Flood Elev= 148.40' Surf.Area= 3,301 sf Storage= 1,481 cf Plug-Flow detention time= 3.6 min calculated for 0.081 af (100% of inflow) Center-of-Mass det. time= 3.3 min ( 780.2 - 776.9 ) Volume Invert Avail.Storage Storage Description #1 147.50' 1,440 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,481 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 1,764 441 441 148.40 3,233 999 1,440 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 19.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.09' S= 0.0216 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 139HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.04 cfs @ 12.22 hrs HW=147.94' (Free Discharge) 2=Exfiltration ( Controls 0.04 cfs) Primary OutFlow Max=0.56 cfs @ 12.22 hrs HW=147.94' (Free Discharge) 3=Culvert (Passes 0.56 cfs of 6.48 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.56 cfs @ 6.40 fps) Summary for Pond 13P: RG13 Inflow Area = 0.079 ac, 73.59% Impervious, Inflow Depth > 5.24" for 50-Year event Inflow = 0.51 cfs @ 12.07 hrs, Volume= 0.035 af Outflow = 0.50 cfs @ 12.08 hrs, Volume= 0.035 af, Atten= 1%, Lag= 0.6 min Discarded = 0.00 cfs @ 12.08 hrs, Volume= 0.001 af Primary = 0.50 cfs @ 12.08 hrs, Volume= 0.033 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.59' @ 12.08 hrs Surf.Area= 60 sf Storage= 23 cf Flood Elev= 148.70' Surf.Area= 1,047 sf Storage= 282 cf Plug-Flow detention time= 0.8 min calculated for 0.035 af (100% of inflow) Center-of-Mass det. time= 0.6 min ( 756.5 - 755.9 ) Volume Invert Avail.Storage Storage Description #1 147.50' 261 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 13 cf 3.21'W x 11.33'L x 1.21'H Field A 44 cf Overall - 10 cf Embedded = 33 cf x 40.0% Voids #3A 146.00' 8 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf Row Length Adjustment= -10.00' x 0.81 sf x 1 rows 282 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 127 32 32 148.40 249 75 107 148.50 269 26 133 148.70 1,011 128 261 Device Routing Invert Outlet Devices #1 Device 3 148.30'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.10'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 140HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 145.10' / 144.84' S= 0.0260 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.08 hrs HW=147.59' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.50 cfs @ 12.08 hrs HW=147.59' (Free Discharge) 3=Culvert (Passes 0.50 cfs of 5.34 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.50 cfs @ 5.75 fps) Summary for Pond 14P: RG14 Inflow Area = 0.050 ac, 59.73% Impervious, Inflow Depth > 4.68" for 50-Year event Inflow = 0.29 cfs @ 12.07 hrs, Volume= 0.019 af Outflow = 0.28 cfs @ 12.10 hrs, Volume= 0.019 af, Atten= 6%, Lag= 1.6 min Discarded = 0.00 cfs @ 12.10 hrs, Volume= 0.002 af Primary = 0.28 cfs @ 12.10 hrs, Volume= 0.018 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.60' @ 12.10 hrs Surf.Area= 68 sf Storage= 20 cf Flood Elev= 148.70' Surf.Area= 1,131 sf Storage= 357 cf Plug-Flow detention time= 1.6 min calculated for 0.019 af (100% of inflow) Center-of-Mass det. time= 1.2 min ( 769.6 - 768.3 ) Volume Invert Avail.Storage Storage Description #1 148.00' 316 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 357 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 0 0 0 148.30 331 50 50 148.40 450 39 89 148.70 1,063 227 316 Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.26'12.0" Round Culvert Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 141HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.10' / 145.26' S= -0.0160 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.10 hrs HW=146.60' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.28 cfs @ 12.10 hrs HW=146.60' (Free Discharge) 3=Culvert (Passes 0.28 cfs of 3.35 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.28 cfs @ 3.17 fps) Summary for Pond 15P: RG15 Inflow Area = 0.065 ac, 51.91% Impervious, Inflow Depth > 4.36" for 50-Year event Inflow = 0.36 cfs @ 12.07 hrs, Volume= 0.024 af Outflow = 0.34 cfs @ 12.10 hrs, Volume= 0.024 af, Atten= 7%, Lag= 1.8 min Discarded = 0.00 cfs @ 12.10 hrs, Volume= 0.002 af Primary = 0.33 cfs @ 12.10 hrs, Volume= 0.022 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.80' @ 12.10 hrs Surf.Area= 68 sf Storage= 28 cf Flood Elev= 148.70' Surf.Area= 880 sf Storage= 337 cf Plug-Flow detention time= 1.6 min calculated for 0.024 af (100% of inflow) Center-of-Mass det. time= 1.2 min ( 776.0 - 774.8 ) Volume Invert Avail.Storage Storage Description #1 147.80' 296 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 337 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.80 0 0 0 148.00 173 17 17 148.30 300 71 88 148.40 354 33 121 148.70 812 175 296 Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 142HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.20'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.20' / 144.84' S= 0.0360 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.10 hrs HW=146.80' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.33 cfs @ 12.10 hrs HW=146.80' (Free Discharge) 3=Culvert (Passes 0.33 cfs of 3.96 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.33 cfs @ 3.83 fps) Summary for Pond 16P: INF-10+11 Inflow Area = 0.368 ac, 90.56% Impervious, Inflow Depth > 6.02" for 50-Year event Inflow = 2.55 cfs @ 12.07 hrs, Volume= 0.185 af Outflow = 2.55 cfs @ 12.07 hrs, Volume= 0.173 af, Atten= 0%, Lag= 0.0 min Discarded = 0.04 cfs @ 12.07 hrs, Volume= 0.041 af Primary = 2.51 cfs @ 12.07 hrs, Volume= 0.133 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.36' @ 12.07 hrs Surf.Area= 909 sf Storage= 495 cf Flood Elev= 149.00' Surf.Area= 11,205 sf Storage= 3,082 cf Plug-Flow detention time= 38.2 min calculated for 0.173 af (94% of inflow) Center-of-Mass det. time= 14.6 min ( 746.2 - 731.7 ) Volume Invert Avail.Storage Storage Description #1 146.00' 271 cf Stone Bedding (Prismatic) Listed below (Recalc) 897 cf Overall - 219 cf Embedded = 678 cf x 40.0% Voids #2 146.08' 219 cf 10.0" Round Pipe Storage Inside #1 L= 402.0' #3 147.00' 2,592 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,082 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 897 0 0 147.00 897 897 897 Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 143HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 5,154 1,290 1,296 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.70'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.44' S= 0.0081 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.80'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0194 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.04 cfs @ 12.07 hrs HW=147.36' (Free Discharge) 5=Exfiltration ( Controls 0.04 cfs) Primary OutFlow Max=2.51 cfs @ 12.07 hrs HW=147.36' (Free Discharge) 2=Culvert (Passes 1.25 cfs of 5.55 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 1.25 cfs @ 1.66 fps) 4=Culvert (Passes 1.25 cfs of 5.42 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 1.25 cfs @ 1.66 fps) Summary for Pond 17P: INF-6+8 Inflow Area = 0.293 ac, 88.50% Impervious, Inflow Depth > 5.87" for 50-Year event Inflow = 2.01 cfs @ 12.07 hrs, Volume= 0.143 af Outflow = 2.01 cfs @ 12.07 hrs, Volume= 0.137 af, Atten= 0%, Lag= 0.0 min Discarded = 0.02 cfs @ 12.07 hrs, Volume= 0.026 af Primary = 1.99 cfs @ 12.07 hrs, Volume= 0.112 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.14' @ 12.07 hrs Surf.Area= 628 sf Storage= 335 cf Flood Elev= 148.90' Surf.Area= 14,038 sf Storage= 3,704 cf Plug-Flow detention time= 30.7 min calculated for 0.137 af (95% of inflow) Center-of-Mass det. time= 12.8 min ( 750.4 - 737.6 ) Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 144HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Volume Invert Avail.Storage Storage Description #1 146.00' 188 cf Stone Bedding (Prismatic) Listed below (Recalc) 616 cf Overall - 146 cf Embedded = 470 cf x 40.0% Voids #2 146.08' 146 cf 10.0" Round Pipe Storage Inside #1 L= 267.0' #3 147.00' 3,371 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,704 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 616 0 0 147.00 616 616 616 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 6,711 1,679 1,685 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.80'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.32' S= 0.0155 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.50'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.15' S= 0.0113 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.02 cfs @ 12.07 hrs HW=147.14' (Free Discharge) 5=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=1.98 cfs @ 12.07 hrs HW=147.14' (Free Discharge) 2=Culvert (Passes 0.08 cfs of 5.13 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.08 cfs @ 0.66 fps) 4=Culvert (Passes 1.90 cfs of 5.53 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 1.90 cfs @ 1.91 fps) Summary for Pond 18P: INF-5+7 Inflow Area = 0.214 ac, 91.42% Impervious, Inflow Depth > 6.04" for 50-Year event Inflow = 1.49 cfs @ 12.07 hrs, Volume= 0.108 af Outflow = 1.49 cfs @ 12.07 hrs, Volume= 0.100 af, Atten= 0%, Lag= 0.0 min Discarded = 0.03 cfs @ 12.07 hrs, Volume= 0.031 af Primary = 1.46 cfs @ 12.07 hrs, Volume= 0.069 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 50-Year Rainfall=6.94"2018-082 Colvest Northampton As-Built Modifications Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 145HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev= 147.02' @ 12.07 hrs Surf.Area= 664 sf Storage= 358 cf Flood Elev= 148.90' Surf.Area= 5,822 sf Storage= 1,665 cf Plug-Flow detention time= 43.9 min calculated for 0.100 af (93% of inflow) Center-of-Mass det. time= 17.4 min ( 748.8 - 731.4 ) Volume Invert Avail.Storage Storage Description #1 145.60' 199 cf Stone Bedding (Prismatic) Listed below (Recalc) 652 cf Overall - 154 cf Embedded = 498 cf x 40.0% Voids #2 145.68' 154 cf 10.0" Round Pipe Storage Inside #1 L= 282.0' #3 146.60' 1,312 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 1,665 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 145.60 652 0 0 146.60 652 652 652 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.60 6 0 0 148.00 6 8 8 148.50 2,585 648 656 Device Routing Invert Outlet Devices #1 Device 2 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.60'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.60' / 144.32' S= 0.0097 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.90'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.70'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.15' S= 0.0190 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 145.60'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.03 cfs @ 12.07 hrs HW=147.02' (Free Discharge) 5=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=1.45 cfs @ 12.07 hrs HW=147.02' (Free Discharge) 2=Culvert (Passes 1.03 cfs of 5.25 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 1.03 cfs @ 1.55 fps) 4=Culvert (Passes 0.43 cfs of 5.11 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.43 cfs @ 1.15 fps) Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 146HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Time span=1.00-20.00 hrs, dt=0.01 hrs, 1901 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind method - Pond routing by Stor-Ind method Runoff Area=8,350 sf 98.42% Impervious Runoff Depth>7.12"Subcatchment 1S: A1 Tc=5.0 min CN=97 Runoff=1.52 cfs 0.114 af Runoff Area=4,496 sf 92.70% Impervious Runoff Depth>6.88"Subcatchment 2S: A2 Tc=5.0 min CN=95 Runoff=0.81 cfs 0.059 af Runoff Area=6,870 sf 97.82% Impervious Runoff Depth>7.12"Subcatchment 3S: A3 Tc=5.0 min CN=97 Runoff=1.25 cfs 0.094 af Runoff Area=8,648 sf 82.34% Impervious Runoff Depth>6.41"Subcatchment 4S: A4 Tc=5.0 min CN=91 Runoff=1.51 cfs 0.106 af Runoff Area=25,964 sf 100.00% Impervious Runoff Depth>7.23"Subcatchment 5S: B2 Tc=5.0 min CN=98 Runoff=4.74 cfs 0.359 af Runoff Area=7,072 sf 0.00% Impervious Runoff Depth>3.06"Subcatchment 6S: POND Tc=0.0 min CN=61 Runoff=0.76 cfs 0.041 af Runoff Area=57,882 sf 0.00% Impervious Runoff Depth>6.41"Subcatchment 7S: PRE REAR Tc=5.0 min CN=91 Runoff=10.12 cfs 0.710 af Runoff Area=5,095 sf 91.89% Impervious Runoff Depth>6.88"Subcatchment 8S: A5 Tc=5.0 min CN=95 Runoff=0.92 cfs 0.067 af Runoff Area=6,947 sf 89.75% Impervious Runoff Depth>6.76"Subcatchment 9S: A6 Tc=5.0 min CN=94 Runoff=1.24 cfs 0.090 af Runoff Area=4,230 sf 90.85% Impervious Runoff Depth>6.88"Subcatchment 10S: A7 Tc=5.0 min CN=95 Runoff=0.76 cfs 0.056 af Runoff Area=5,823 sf 87.02% Impervious Runoff Depth>6.64"Subcatchment 11S: A8 Tc=5.0 min CN=93 Runoff=1.04 cfs 0.074 af Runoff Area=11,231 sf 77.08% Impervious Runoff Depth>6.29"Subcatchment 12S: A9 Tc=5.0 min CN=90 Runoff=1.94 cfs 0.135 af Runoff Area=9,635 sf 93.98% Impervious Runoff Depth>7.00"Subcatchment 13S: A10 Tc=5.0 min CN=96 Runoff=1.75 cfs 0.129 af Runoff Area=6,395 sf 85.41% Impervious Runoff Depth>6.64"Subcatchment 14S: A11 Tc=5.0 min CN=93 Runoff=1.14 cfs 0.081 af Runoff Area=9,957 sf 48.28% Impervious Runoff Depth>5.02"Subcatchment 15S: A12 Tc=5.0 min CN=79 Runoff=1.47 cfs 0.096 af Runoff Area=3,453 sf 73.59% Impervious Runoff Depth>6.06"Subcatchment 16S: A13 Tc=5.0 min CN=88 Runoff=0.58 cfs 0.040 af Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 147HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Runoff Area=2,168 sf 59.73% Impervious Runoff Depth>5.48"Subcatchment 17S: A14 Tc=5.0 min CN=83 Runoff=0.34 cfs 0.023 af Runoff Area=2,826 sf 51.91% Impervious Runoff Depth>5.14"Subcatchment 18S: A15 Tc=5.0 min CN=80 Runoff=0.42 cfs 0.028 af Runoff Area=6,971 sf 100.00% Impervious Runoff Depth>7.23"Subcatchment 19S: B1 Tc=5.0 min CN=98 Runoff=1.27 cfs 0.096 af Runoff Area=71,761 sf 44.08% Impervious Runoff Depth>6.17"Subcatchment 20S: PRE FRONT Tc=5.0 min CN=89 Runoff=12.29 cfs 0.848 af Peak Elev=145.54' Inflow=1.52 cfs 0.114 afPond 1C: CB1 12.0" Round Culvert n=0.012 L=124.0' S=0.0050 '/' Outflow=1.52 cfs 0.114 af Peak Elev=145.65' Inflow=7.07 cfs 0.532 afPond 1D: DMH1 18.0" Round Culvert n=0.012 L=58.0' S=0.0050 '/' Outflow=7.07 cfs 0.532 af Peak Elev=146.93' Storage=11,013 cf Inflow=10.33 cfs 0.773 afPond 1P: POST REAR Discarded=0.13 cfs 0.126 af Primary=9.29 cfs 0.437 af Outflow=9.43 cfs 0.563 af Peak Elev=145.46' Inflow=0.81 cfs 0.059 afPond 2C: CB2 12.0" Round Culvert n=0.012 L=8.0' S=0.0437 '/' Outflow=0.81 cfs 0.059 af Peak Elev=145.66' Inflow=8.32 cfs 0.626 afPond 2D: DMH2 18.0" Round Culvert n=0.012 L=50.0' S=0.0050 '/' Outflow=8.32 cfs 0.626 af Peak Elev=148.13' Storage=8,224 cf Inflow=10.67 cfs 0.775 afPond 2P: POST FRONT Outflow=11.25 cfs 0.736 af Peak Elev=145.45' Inflow=1.25 cfs 0.094 afPond 3C: CB3 12.0" Round Culvert n=0.012 L=13.0' S=0.0115 '/' Outflow=1.25 cfs 0.094 af Peak Elev=145.63' Inflow=9.83 cfs 0.732 afPond 3D: DMH3 18.0" Round Culvert n=0.012 L=54.0' S=0.0056 '/' Outflow=9.83 cfs 0.732 af Peak Elev=145.51' Inflow=1.51 cfs 0.106 afPond 4C: CB4 12.0" Round Culvert n=0.012 L=8.0' S=0.0188 '/' Outflow=1.51 cfs 0.106 af Peak Elev=148.11' Storage=589 cf Inflow=1.94 cfs 0.135 afPond 9P: RG9 Discarded=0.03 cfs 0.004 af Primary=1.54 cfs 0.131 af Outflow=1.58 cfs 0.135 af Peak Elev=148.02' Storage=514 cf Inflow=1.47 cfs 0.096 afPond 12P: RG12 Discarded=0.05 cfs 0.004 af Primary=0.64 cfs 0.091 af Outflow=0.69 cfs 0.096 af Peak Elev=147.79' Storage=32 cf Inflow=0.58 cfs 0.040 afPond 13P: RG13 Discarded=0.00 cfs 0.001 af Primary=0.54 cfs 0.039 af Outflow=0.54 cfs 0.040 af Peak Elev=146.74' Storage=26 cf Inflow=0.34 cfs 0.023 afPond 14P: RG14 Discarded=0.00 cfs 0.002 af Primary=0.32 cfs 0.021 af Outflow=0.32 cfs 0.023 af Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 148HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev=147.02' Storage=36 cf Inflow=0.42 cfs 0.028 afPond 15P: RG15 Discarded=0.00 cfs 0.002 af Primary=0.39 cfs 0.026 af Outflow=0.39 cfs 0.028 af Peak Elev=147.38' Storage=495 cf Inflow=2.88 cfs 0.210 afPond 16P: INF-10+11 Discarded=0.04 cfs 0.042 af Primary=2.85 cfs 0.157 af Outflow=2.88 cfs 0.199 af Peak Elev=147.16' Storage=336 cf Inflow=2.28 cfs 0.164 afPond 17P: INF-6+8 Discarded=0.02 cfs 0.026 af Primary=2.26 cfs 0.131 af Outflow=2.28 cfs 0.157 af Peak Elev=147.04' Storage=358 cf Inflow=1.68 cfs 0.123 afPond 18P: INF-5+7 Discarded=0.03 cfs 0.032 af Primary=1.65 cfs 0.083 af Outflow=1.68 cfs 0.115 af Total Runoff Area = 6.101 ac Runoff Volume = 3.245 af Average Runoff Depth = 6.38" 45.85% Pervious = 2.798 ac 54.15% Impervious = 3.304 ac Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 149HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: A1 Runoff = 1.52 cfs @ 12.07 hrs, Volume= 0.114 af, Depth> 7.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 8,218 98 Paved parking, HSG B 132 61 >75% Grass cover, Good, HSG B 8,350 97 Weighted Average 132 1.58% Pervious Area 8,218 98.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2S: A2 Runoff = 0.81 cfs @ 12.07 hrs, Volume= 0.059 af, Depth> 6.88" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 4,168 98 Paved parking, HSG B 328 61 >75% Grass cover, Good, HSG B 4,496 95 Weighted Average 328 7.30% Pervious Area 4,168 92.70% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 3S: A3 Runoff = 1.25 cfs @ 12.07 hrs, Volume= 0.094 af, Depth> 7.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 6,720 98 Paved parking, HSG B 150 61 >75% Grass cover, Good, HSG B 6,870 97 Weighted Average 150 2.18% Pervious Area 6,720 97.82% Impervious Area Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 150HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 4S: A4 Runoff = 1.51 cfs @ 12.07 hrs, Volume= 0.106 af, Depth> 6.41" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 7,121 98 Paved parking, HSG B 1,527 61 >75% Grass cover, Good, HSG B 8,648 91 Weighted Average 1,527 17.66% Pervious Area 7,121 82.34% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 5S: B2 Runoff = 4.74 cfs @ 12.07 hrs, Volume= 0.359 af, Depth> 7.23" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 25,964 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 25,964 98 Weighted Average 25,964 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 6S: POND Runoff = 0.76 cfs @ 12.00 hrs, Volume= 0.041 af, Depth> 3.06" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 151HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 7,072 61 >75% Grass cover, Good, HSG B 7,072 100.00% Pervious Area Summary for Subcatchment 7S: PRE REAR Runoff = 10.12 cfs @ 12.07 hrs, Volume= 0.710 af, Depth> 6.41" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 9,064 67 Brush, Poor, HSG B 48,818 96 Gravel surface, HSG B 57,882 91 Weighted Average 57,882 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 8S: A5 Runoff = 0.92 cfs @ 12.07 hrs, Volume= 0.067 af, Depth> 6.88" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 4,682 98 Paved parking, HSG B 413 61 >75% Grass cover, Good, HSG B 5,095 95 Weighted Average 413 8.11% Pervious Area 4,682 91.89% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 9S: A6 Runoff = 1.24 cfs @ 12.07 hrs, Volume= 0.090 af, Depth> 6.76" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 152HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 6,235 98 Paved parking, HSG B 712 61 >75% Grass cover, Good, HSG B 6,947 94 Weighted Average 712 10.25% Pervious Area 6,235 89.75% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 10S: A7 Runoff = 0.76 cfs @ 12.07 hrs, Volume= 0.056 af, Depth> 6.88" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 3,843 98 Paved parking, HSG B 387 61 >75% Grass cover, Good, HSG B 4,230 95 Weighted Average 387 9.15% Pervious Area 3,843 90.85% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 11S: A8 Runoff = 1.04 cfs @ 12.07 hrs, Volume= 0.074 af, Depth> 6.64" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 5,067 98 Paved parking, HSG B 756 61 >75% Grass cover, Good, HSG B 5,823 93 Weighted Average 756 12.98% Pervious Area 5,067 87.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 153HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 12S: A9 Runoff = 1.94 cfs @ 12.07 hrs, Volume= 0.135 af, Depth> 6.29" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 8,657 98 Paved parking, HSG B 2,574 61 >75% Grass cover, Good, HSG B 11,231 90 Weighted Average 2,574 22.92% Pervious Area 8,657 77.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 13S: A10 Runoff = 1.75 cfs @ 12.07 hrs, Volume= 0.129 af, Depth> 7.00" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 9,055 98 Paved parking, HSG B 580 61 >75% Grass cover, Good, HSG B 9,635 96 Weighted Average 580 6.02% Pervious Area 9,055 93.98% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 14S: A11 Runoff = 1.14 cfs @ 12.07 hrs, Volume= 0.081 af, Depth> 6.64" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 5,462 98 Paved parking, HSG B 933 61 >75% Grass cover, Good, HSG B 6,395 93 Weighted Average 933 14.59% Pervious Area 5,462 85.41% Impervious Area Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 154HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 15S: A12 Runoff = 1.47 cfs @ 12.07 hrs, Volume= 0.096 af, Depth> 5.02" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 4,807 98 Paved parking, HSG B 5,150 61 >75% Grass cover, Good, HSG B 9,957 79 Weighted Average 5,150 51.72% Pervious Area 4,807 48.28% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 16S: A13 Runoff = 0.58 cfs @ 12.07 hrs, Volume= 0.040 af, Depth> 6.06" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 2,541 98 Paved parking, HSG B 912 61 >75% Grass cover, Good, HSG B 3,453 88 Weighted Average 912 26.41% Pervious Area 2,541 73.59% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 17S: A14 Runoff = 0.34 cfs @ 12.07 hrs, Volume= 0.023 af, Depth> 5.48" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 155HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Area (sf) CN Description 1,295 98 Paved parking, HSG B 873 61 >75% Grass cover, Good, HSG B 2,168 83 Weighted Average 873 40.27% Pervious Area 1,295 59.73% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 18S: A15 Runoff = 0.42 cfs @ 12.07 hrs, Volume= 0.028 af, Depth> 5.14" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 1,467 98 Paved parking, HSG B 1,359 61 >75% Grass cover, Good, HSG B 2,826 80 Weighted Average 1,359 48.09% Pervious Area 1,467 51.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 19S: B1 Runoff = 1.27 cfs @ 12.07 hrs, Volume= 0.096 af, Depth> 7.23" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 6,971 98 Roofs, HSG B 0 61 >75% Grass cover, Good, HSG B 6,971 98 Weighted Average 6,971 100.00% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 156HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Subcatchment 20S: PRE FRONT Runoff = 12.29 cfs @ 12.07 hrs, Volume= 0.848 af, Depth> 6.17" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82" Area (sf) CN Description 24,527 96 Gravel surface, HSG B 15,601 61 >75% Grass cover, Good, HSG B 31,633 98 Paved parking, HSG B 71,761 89 Weighted Average 40,128 55.92% Pervious Area 31,633 44.08% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Pond 1C: CB1 Inflow Area = 0.192 ac, 98.42% Impervious, Inflow Depth > 7.12" for 100-Year event Inflow = 1.52 cfs @ 12.07 hrs, Volume= 0.114 af Outflow = 1.52 cfs @ 12.07 hrs, Volume= 0.114 af, Atten= 0%, Lag= 0.0 min Primary = 1.52 cfs @ 12.07 hrs, Volume= 0.114 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.54' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 124.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=1.52 cfs @ 12.07 hrs HW=145.54' (Free Discharge) 1=Culvert (Barrel Controls 1.52 cfs @ 3.38 fps) Summary for Pond 1D: DMH1 Inflow Area = 0.891 ac, 98.81% Impervious, Inflow Depth > 7.17" for 100-Year event Inflow = 7.07 cfs @ 12.07 hrs, Volume= 0.532 af Outflow = 7.07 cfs @ 12.07 hrs, Volume= 0.532 af, Atten= 0%, Lag= 0.0 min Primary = 7.07 cfs @ 12.07 hrs, Volume= 0.532 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.65' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.00'18.0" Round 18" CPEP Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 157HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 58.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.00' / 143.71' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=7.07 cfs @ 12.07 hrs HW=145.65' (Free Discharge) 1=18" CPEP (Barrel Controls 7.07 cfs @ 4.54 fps) Summary for Pond 1P: POST REAR Inflow Area = 1.410 ac, 85.00% Impervious, Inflow Depth > 6.58" for 100-Year event Inflow = 10.33 cfs @ 12.07 hrs, Volume= 0.773 af Outflow = 9.43 cfs @ 12.10 hrs, Volume= 0.563 af, Atten= 9%, Lag= 2.0 min Discarded = 0.13 cfs @ 12.10 hrs, Volume= 0.126 af Primary = 9.29 cfs @ 12.10 hrs, Volume= 0.437 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.93' @ 12.10 hrs Surf.Area= 4,523 sf Storage= 11,013 cf Plug-Flow detention time= 124.5 min calculated for 0.562 af (73% of inflow) Center-of-Mass det. time= 55.7 min ( 780.8 - 725.1 ) Volume Invert Avail.Storage Storage Description #1 143.00' 11,310 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 143.00 1,320 0 0 144.00 1,986 1,653 1,653 145.00 2,752 2,369 4,022 146.00 3,619 3,186 7,208 147.00 4,586 4,103 11,310 Device Routing Invert Outlet Devices #1 Discarded 143.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 135.00' #2 Primary 146.50'12.0' long x 16.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.68 2.70 2.70 2.64 2.63 2.64 2.64 2.63 Discarded OutFlow Max=0.13 cfs @ 12.10 hrs HW=146.93' (Free Discharge) 1=Exfiltration ( Controls 0.13 cfs) Primary OutFlow Max=9.28 cfs @ 12.10 hrs HW=146.93' (Free Discharge) 2=Broad-Crested Rectangular Weir (Weir Controls 9.28 cfs @ 1.78 fps) Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 158HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 2C: CB2 Inflow Area = 0.103 ac, 92.70% Impervious, Inflow Depth > 6.88" for 100-Year event Inflow = 0.81 cfs @ 12.07 hrs, Volume= 0.059 af Outflow = 0.81 cfs @ 12.07 hrs, Volume= 0.059 af, Atten= 0%, Lag= 0.0 min Primary = 0.81 cfs @ 12.07 hrs, Volume= 0.059 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.46' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 145.00'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.00' / 144.65' S= 0.0437 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=0.81 cfs @ 12.07 hrs HW=145.46' (Free Discharge) 1=Culvert (Inlet Controls 0.81 cfs @ 2.31 fps) Summary for Pond 2D: DMH2 Inflow Area = 1.049 ac, 98.66% Impervious, Inflow Depth > 7.16" for 100-Year event Inflow = 8.32 cfs @ 12.07 hrs, Volume= 0.626 af Outflow = 8.32 cfs @ 12.07 hrs, Volume= 0.626 af, Atten= 0%, Lag= 0.0 min Primary = 8.32 cfs @ 12.07 hrs, Volume= 0.626 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.66' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.63'18.0" Round 18" CPEP L= 50.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.63' / 143.38' S= 0.0050 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=8.32 cfs @ 12.07 hrs HW=145.66' (Free Discharge) 1=18" CPEP (Barrel Controls 8.32 cfs @ 4.71 fps) Summary for Pond 2P: POST FRONT Inflow Area = 1.716 ac, 80.40% Impervious, Inflow Depth > 5.42" for 100-Year event Inflow = 10.67 cfs @ 12.09 hrs, Volume= 0.775 af Outflow = 11.25 cfs @ 12.09 hrs, Volume= 0.736 af, Atten= 0%, Lag= 0.1 min Primary = 11.25 cfs @ 12.09 hrs, Volume= 0.736 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Starting Elev= 144.27' Surf.Area= 2,195 sf Storage= 940 cf Peak Elev= 148.13' @ 12.09 hrs Surf.Area= 508 sf Storage= 8,224 cf (7,284 cf above start) Flood Elev= 148.20' Surf.Area= 508 sf Storage= 8,258 cf (7,318 cf above start) Plug-Flow detention time= 64.4 min calculated for 0.714 af (92% of inflow) Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 159HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Center-of-Mass det. time= 34.8 min ( 783.8 - 749.0 ) Volume Invert Avail.Storage Storage Description #1 143.90' 509 cf 4.00'D x 4.50'H DMH x 9 #2 143.86' 226 cf 30.0" Round 30" Flat CPEP (10-11) L= 46.0' S= 0.0070 '/' #3 143.74' 324 cf 30.0" Round 30" Flat CPEP (11-12) L= 66.0' S= 0.0003 '/' #4 143.78' 275 cf 30.0" Round 30" Flat CPEP (12-Out) L= 56.0' S= 0.0016 '/' #5 143.88' 1,924 cf 30.0" Round 30" Flat CPEP (9-Out) x 4 L= 98.0' S= 0.0030 '/' #6 143.39' 1,031 cf 30.0" Round 30" Flat CPEP (6-9) x 3 L= 70.0' S= 0.0007 '/' #7 143.59' 260 cf 30.0" Round 30" Flat CPEP (8-9) L= 53.0' S= 0.0008 '/' #8 143.38' 476 cf 30.0" Round 30" Flat CPEP (7-8) L= 97.0' S= 0.0008 '/' #9 143.39' 285 cf 30.0" Round 30" Flat CPEP (5-6) L= 58.0' S= 0.0007 '/' #10 143.50' 422 cf 30.0" Round 30" Flat CPEP (4-5) L= 86.0' S= 0.0003 '/' #11 148.00' 333 cf Custom Stage Data (Prismatic) Listed below (Recalc) #12 144.27' 2,376 cf 30.0" Round Prop. 30" Flat CPEP L= 484.0' #13 144.27' 113 cf 4.00'D x 4.50'H Prop. DMH x 2 8,554 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 370 0 0 148.90 370 333 333 Device Routing Invert Outlet Devices #1 Device 3 144.27'10.0" Vert. 10" Orifice C= 0.600 #2 Device 3 146.85'36.0" W x 4.0" H Vert. 4"x36" Weir/Orifice C= 0.600 #3 Primary 144.65'12.0" Round 12" Culvert L= 16.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.65' / 143.50' S= 0.0719 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Primary 148.00'37.0' long x 10.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=10.88 cfs @ 12.09 hrs HW=148.13' (Free Discharge) 3=12" Culvert (Inlet Controls 6.53 cfs @ 8.31 fps) 1=10" Orifice (Passes < 4.87 cfs potential flow) 2=4"x36" Weir/Orifice (Passes < 5.08 cfs potential flow) 4=Broad-Crested Rectangular Weir (Weir Controls 4.35 cfs @ 0.90 fps) Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 160HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Summary for Pond 3C: CB3 Inflow Area = 0.158 ac, 97.82% Impervious, Inflow Depth > 7.12" for 100-Year event Inflow = 1.25 cfs @ 12.07 hrs, Volume= 0.094 af Outflow = 1.25 cfs @ 12.07 hrs, Volume= 0.094 af, Atten= 0%, Lag= 0.0 min Primary = 1.25 cfs @ 12.07 hrs, Volume= 0.094 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.45' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 13.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0115 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=1.25 cfs @ 12.07 hrs HW=145.45' (Free Discharge) 1=Culvert (Barrel Controls 1.25 cfs @ 3.29 fps) Summary for Pond 3D: DMH3 Inflow Area = 1.247 ac, 96.07% Impervious, Inflow Depth > 7.04" for 100-Year event Inflow = 9.83 cfs @ 12.07 hrs, Volume= 0.732 af Outflow = 9.83 cfs @ 12.07 hrs, Volume= 0.732 af, Atten= 0%, Lag= 0.0 min Primary = 9.83 cfs @ 12.07 hrs, Volume= 0.732 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.63' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 143.30'18.0" Round Culvert L= 54.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 143.30' / 143.00' S= 0.0056 '/' Cc= 0.900 n= 0.012, Flow Area= 1.77 sf Primary OutFlow Max=9.83 cfs @ 12.07 hrs HW=145.63' (Free Discharge) 1=Culvert (Barrel Controls 9.83 cfs @ 5.56 fps) Summary for Pond 4C: CB4 Inflow Area = 0.199 ac, 82.34% Impervious, Inflow Depth > 6.41" for 100-Year event Inflow = 1.51 cfs @ 12.07 hrs, Volume= 0.106 af Outflow = 1.51 cfs @ 12.07 hrs, Volume= 0.106 af, Atten= 0%, Lag= 0.0 min Primary = 1.51 cfs @ 12.07 hrs, Volume= 0.106 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 145.51' @ 12.07 hrs Device Routing Invert Outlet Devices #1 Primary 144.80'12.0" Round Culvert L= 8.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 161HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 144.80' / 144.65' S= 0.0188 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf Primary OutFlow Max=1.51 cfs @ 12.07 hrs HW=145.51' (Free Discharge) 1=Culvert (Barrel Controls 1.51 cfs @ 3.53 fps) Summary for Pond 9P: RG9 Inflow Area = 0.258 ac, 77.08% Impervious, Inflow Depth > 6.29" for 100-Year event Inflow = 1.94 cfs @ 12.07 hrs, Volume= 0.135 af Outflow = 1.58 cfs @ 12.12 hrs, Volume= 0.135 af, Atten= 19%, Lag= 3.2 min Discarded = 0.03 cfs @ 12.12 hrs, Volume= 0.004 af Primary = 1.54 cfs @ 12.12 hrs, Volume= 0.131 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 148.11' @ 12.12 hrs Surf.Area= 1,154 sf Storage= 589 cf Flood Elev= 148.40' Surf.Area= 1,804 sf Storage= 1,004 cf Plug-Flow detention time= 4.0 min calculated for 0.135 af (100% of inflow) Center-of-Mass det. time= 3.8 min ( 750.6 - 746.7 ) Volume Invert Avail.Storage Storage Description #1 147.40' 963 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 145.60' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 145.60' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,004 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.40 632 0 0 148.00 853 445 445 148.40 1,736 518 963 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 145.60'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 34.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 143.94' S= 0.0165 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 145.60'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 162HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.03 cfs @ 12.12 hrs HW=148.10' (Free Discharge) 2=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=1.53 cfs @ 12.12 hrs HW=148.10' (Free Discharge) 3=Culvert (Passes 1.53 cfs of 6.66 cfs potential flow) 1=CB Inlet (Weir Controls 0.89 cfs @ 1.06 fps) 4=Underdrain (Orifice Controls 0.64 cfs @ 7.36 fps) Summary for Pond 12P: RG12 Inflow Area = 0.229 ac, 48.28% Impervious, Inflow Depth > 5.02" for 100-Year event Inflow = 1.47 cfs @ 12.07 hrs, Volume= 0.096 af Outflow = 0.69 cfs @ 12.23 hrs, Volume= 0.096 af, Atten= 53%, Lag= 9.2 min Discarded = 0.05 cfs @ 12.23 hrs, Volume= 0.004 af Primary = 0.64 cfs @ 12.23 hrs, Volume= 0.091 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 148.02' @ 12.23 hrs Surf.Area= 1,898 sf Storage= 514 cf Flood Elev= 148.40' Surf.Area= 3,301 sf Storage= 1,481 cf Plug-Flow detention time= 4.5 min calculated for 0.096 af (100% of inflow) Center-of-Mass det. time= 4.3 min ( 777.2 - 772.9 ) Volume Invert Avail.Storage Storage Description #1 147.50' 1,440 cf Rain Garden (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 1,481 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 1,764 441 441 148.40 3,233 999 1,440 Device Routing Invert Outlet Devices #1 Device 3 148.00'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 144.50'12.0" Round Culvert L= 19.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.09' S= 0.0216 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 163HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Discarded OutFlow Max=0.05 cfs @ 12.23 hrs HW=148.02' (Free Discharge) 2=Exfiltration ( Controls 0.05 cfs) Primary OutFlow Max=0.63 cfs @ 12.23 hrs HW=148.02' (Free Discharge) 3=Culvert (Passes 0.63 cfs of 6.57 cfs potential flow) 1=CB Inlet (Weir Controls 0.06 cfs @ 0.44 fps) 4=Underdrain (Orifice Controls 0.57 cfs @ 6.55 fps) Summary for Pond 13P: RG13 Inflow Area = 0.079 ac, 73.59% Impervious, Inflow Depth > 6.06" for 100-Year event Inflow = 0.58 cfs @ 12.07 hrs, Volume= 0.040 af Outflow = 0.54 cfs @ 12.10 hrs, Volume= 0.040 af, Atten= 8%, Lag= 1.9 min Discarded = 0.00 cfs @ 12.10 hrs, Volume= 0.001 af Primary = 0.54 cfs @ 12.10 hrs, Volume= 0.039 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.79' @ 12.10 hrs Surf.Area= 110 sf Storage= 32 cf Flood Elev= 148.70' Surf.Area= 1,047 sf Storage= 282 cf Plug-Flow detention time= 0.8 min calculated for 0.040 af (100% of inflow) Center-of-Mass det. time= 0.6 min ( 753.1 - 752.4 ) Volume Invert Avail.Storage Storage Description #1 147.50' 261 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 13 cf 3.21'W x 11.33'L x 1.21'H Field A 44 cf Overall - 10 cf Embedded = 33 cf x 40.0% Voids #3A 146.00' 8 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf Row Length Adjustment= -10.00' x 0.81 sf x 1 rows 282 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.50 0 0 0 148.00 127 32 32 148.40 249 75 107 148.50 269 26 133 148.70 1,011 128 261 Device Routing Invert Outlet Devices #1 Device 3 148.30'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.10'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 164HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Inlet / Outlet Invert= 145.10' / 144.84' S= 0.0260 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.10 hrs HW=147.79' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.54 cfs @ 12.10 hrs HW=147.79' (Free Discharge) 3=Culvert (Passes 0.54 cfs of 5.59 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.54 cfs @ 6.13 fps) Summary for Pond 14P: RG14 Inflow Area = 0.050 ac, 59.73% Impervious, Inflow Depth > 5.48" for 100-Year event Inflow = 0.34 cfs @ 12.07 hrs, Volume= 0.023 af Outflow = 0.32 cfs @ 12.10 hrs, Volume= 0.023 af, Atten= 7%, Lag= 1.8 min Discarded = 0.00 cfs @ 12.10 hrs, Volume= 0.002 af Primary = 0.32 cfs @ 12.10 hrs, Volume= 0.021 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 146.74' @ 12.10 hrs Surf.Area= 68 sf Storage= 26 cf Flood Elev= 148.70' Surf.Area= 1,131 sf Storage= 357 cf Plug-Flow detention time= 1.6 min calculated for 0.023 af (100% of inflow) Center-of-Mass det. time= 1.2 min ( 765.8 - 764.6 ) Volume Invert Avail.Storage Storage Description #1 148.00' 316 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 357 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 148.00 0 0 0 148.30 331 50 50 148.40 450 39 89 148.70 1,063 227 316 Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.26'12.0" Round Culvert Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 165HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.10' / 145.26' S= -0.0160 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.10 hrs HW=146.74' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.32 cfs @ 12.10 hrs HW=146.74' (Free Discharge) 3=Culvert (Passes 0.32 cfs of 3.73 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.32 cfs @ 3.63 fps) Summary for Pond 15P: RG15 Inflow Area = 0.065 ac, 51.91% Impervious, Inflow Depth > 5.14" for 100-Year event Inflow = 0.42 cfs @ 12.07 hrs, Volume= 0.028 af Outflow = 0.39 cfs @ 12.11 hrs, Volume= 0.028 af, Atten= 8%, Lag= 1.9 min Discarded = 0.00 cfs @ 12.11 hrs, Volume= 0.002 af Primary = 0.39 cfs @ 12.11 hrs, Volume= 0.026 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.02' @ 12.11 hrs Surf.Area= 68 sf Storage= 36 cf Flood Elev= 148.70' Surf.Area= 880 sf Storage= 337 cf Plug-Flow detention time= 1.5 min calculated for 0.028 af (100% of inflow) Center-of-Mass det. time= 1.2 min ( 772.1 - 770.9 ) Volume Invert Avail.Storage Storage Description #1 147.80' 296 cf Custom Stage Data (Prismatic) Listed below (Recalc) #2A 146.00' 25 cf 3.21'W x 21.33'L x 1.21'H Field A 83 cf Overall - 21 cf Embedded = 62 cf x 40.0% Voids #3A 146.00' 16 cf ADS N-12 12" Inside #2 Inside= 12.2"W x 12.2"H => 0.81 sf x 20.00'L = 16.2 cf Outside= 14.5"W x 14.5"H => 1.05 sf x 20.00'L = 20.9 cf 337 cf Total Available Storage Storage Group A created with Chamber Wizard Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.80 0 0 0 148.00 173 17 17 148.30 300 71 88 148.40 354 33 121 148.70 812 175 296 Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 166HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Device Routing Invert Outlet Devices #1 Device 3 148.40'24.0" x 24.0" Horiz. CB Inlet C= 0.600 Limited to weir flow at low heads #2 Discarded 146.00'1.000 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' #3 Primary 145.20'12.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 145.20' / 144.84' S= 0.0360 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #4 Device 3 146.00'4.0" Vert. Underdrain C= 0.600 Discarded OutFlow Max=0.00 cfs @ 12.11 hrs HW=147.01' (Free Discharge) 2=Exfiltration ( Controls 0.00 cfs) Primary OutFlow Max=0.39 cfs @ 12.11 hrs HW=147.01' (Free Discharge) 3=Culvert (Passes 0.39 cfs of 4.34 cfs potential flow) 1=CB Inlet ( Controls 0.00 cfs) 4=Underdrain (Orifice Controls 0.39 cfs @ 4.43 fps) Summary for Pond 16P: INF-10+11 Inflow Area = 0.368 ac, 90.56% Impervious, Inflow Depth > 6.86" for 100-Year event Inflow = 2.88 cfs @ 12.07 hrs, Volume= 0.210 af Outflow = 2.88 cfs @ 12.07 hrs, Volume= 0.199 af, Atten= 0%, Lag= 0.0 min Discarded = 0.04 cfs @ 12.07 hrs, Volume= 0.042 af Primary = 2.85 cfs @ 12.07 hrs, Volume= 0.157 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.38' @ 12.07 hrs Surf.Area= 909 sf Storage= 495 cf Flood Elev= 149.00' Surf.Area= 11,205 sf Storage= 3,082 cf Plug-Flow detention time= 35.6 min calculated for 0.199 af (95% of inflow) Center-of-Mass det. time= 14.3 min ( 743.5 - 729.2 ) Volume Invert Avail.Storage Storage Description #1 146.00' 271 cf Stone Bedding (Prismatic) Listed below (Recalc) 897 cf Overall - 219 cf Embedded = 678 cf x 40.0% Voids #2 146.08' 219 cf 10.0" Round Pipe Storage Inside #1 L= 402.0' #3 147.00' 2,592 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,082 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 897 0 0 147.00 897 897 897 Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 167HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 5,154 1,290 1,296 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.70'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.44' S= 0.0081 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.80'12.0" Round Culvert L= 32.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.18' S= 0.0194 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.04 cfs @ 12.07 hrs HW=147.38' (Free Discharge) 5=Exfiltration ( Controls 0.04 cfs) Primary OutFlow Max=2.85 cfs @ 12.07 hrs HW=147.38' (Free Discharge) 2=Culvert (Passes 1.42 cfs of 5.58 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 1.42 cfs @ 1.73 fps) 4=Culvert (Passes 1.42 cfs of 5.45 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 1.42 cfs @ 1.73 fps) Summary for Pond 17P: INF-6+8 Inflow Area = 0.293 ac, 88.50% Impervious, Inflow Depth > 6.71" for 100-Year event Inflow = 2.28 cfs @ 12.07 hrs, Volume= 0.164 af Outflow = 2.28 cfs @ 12.07 hrs, Volume= 0.157 af, Atten= 0%, Lag= 0.0 min Discarded = 0.02 cfs @ 12.07 hrs, Volume= 0.026 af Primary = 2.26 cfs @ 12.07 hrs, Volume= 0.131 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Peak Elev= 147.16' @ 12.07 hrs Surf.Area= 628 sf Storage= 336 cf Flood Elev= 148.90' Surf.Area= 14,038 sf Storage= 3,704 cf Plug-Flow detention time= 28.6 min calculated for 0.157 af (96% of inflow) Center-of-Mass det. time= 12.4 min ( 747.2 - 734.8 ) Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 168HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Volume Invert Avail.Storage Storage Description #1 146.00' 188 cf Stone Bedding (Prismatic) Listed below (Recalc) 616 cf Overall - 146 cf Embedded = 470 cf x 40.0% Voids #2 146.08' 146 cf 10.0" Round Pipe Storage Inside #1 L= 267.0' #3 147.00' 3,371 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 3,704 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.00 616 0 0 147.00 616 616 616 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 147.00 6 0 0 148.00 6 6 6 148.50 6,711 1,679 1,685 Device Routing Invert Outlet Devices #1 Device 2 147.10'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.80'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.80' / 144.32' S= 0.0155 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.50'12.0" Round Culvert L= 31.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.50' / 144.15' S= 0.0113 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 146.00'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.02 cfs @ 12.07 hrs HW=147.16' (Free Discharge) 5=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=2.25 cfs @ 12.07 hrs HW=147.16' (Free Discharge) 2=Culvert (Passes 0.16 cfs of 5.16 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 0.16 cfs @ 0.82 fps) 4=Culvert (Passes 2.10 cfs of 5.56 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 2.10 cfs @ 1.97 fps) Summary for Pond 18P: INF-5+7 Inflow Area = 0.214 ac, 91.42% Impervious, Inflow Depth > 6.88" for 100-Year event Inflow = 1.68 cfs @ 12.07 hrs, Volume= 0.123 af Outflow = 1.68 cfs @ 12.07 hrs, Volume= 0.115 af, Atten= 0%, Lag= 0.0 min Discarded = 0.03 cfs @ 12.07 hrs, Volume= 0.032 af Primary = 1.65 cfs @ 12.07 hrs, Volume= 0.083 af Routing by Stor-Ind method, Time Span= 1.00-20.00 hrs, dt= 0.01 hrs Type III 24-hr 100-Year Rainfall=7.82"2018-082 Colvest Northampton As-Built Modification Printed 3/19/2021Prepared by J.R. Russo & Associates, LLC Page 169HydroCAD® 10.00-25 s/n 05524 © 2019 HydroCAD Software Solutions LLC Peak Elev= 147.04' @ 12.07 hrs Surf.Area= 664 sf Storage= 358 cf Flood Elev= 148.90' Surf.Area= 5,822 sf Storage= 1,665 cf Plug-Flow detention time= 40.7 min calculated for 0.115 af (94% of inflow) Center-of-Mass det. time= 15.8 min ( 744.7 - 728.9 ) Volume Invert Avail.Storage Storage Description #1 145.60' 199 cf Stone Bedding (Prismatic) Listed below (Recalc) 652 cf Overall - 154 cf Embedded = 498 cf x 40.0% Voids #2 145.68' 154 cf 10.0" Round Pipe Storage Inside #1 L= 282.0' #3 146.60' 1,312 cf Custom Stage Data (Prismatic) Listed below (Recalc) x 2 1,665 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 145.60 652 0 0 146.60 652 652 652 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 146.60 6 0 0 148.00 6 8 8 148.50 2,585 648 656 Device Routing Invert Outlet Devices #1 Device 2 146.80'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #2 Primary 144.60'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.60' / 144.32' S= 0.0097 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #3 Device 4 146.90'3.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) #4 Primary 144.70'12.0" Round Culvert L= 29.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 144.70' / 144.15' S= 0.0190 '/' Cc= 0.900 n= 0.012, Flow Area= 0.79 sf #5 Discarded 145.60'1.020 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 144.00' Discarded OutFlow Max=0.03 cfs @ 12.07 hrs HW=147.04' (Free Discharge) 5=Exfiltration ( Controls 0.03 cfs) Primary OutFlow Max=1.65 cfs @ 12.07 hrs HW=147.04' (Free Discharge) 2=Culvert (Passes 1.14 cfs of 5.27 cfs potential flow) 1=Sharp-Crested Rectangular Weir (Weir Controls 1.14 cfs @ 1.60 fps) 4=Culvert (Passes 0.51 cfs of 5.13 cfs potential flow) 3=Sharp-Crested Rectangular Weir (Weir Controls 0.51 cfs @ 1.22 fps)