Revised Stormwater Management Report

POA 2 proposed 2024-05-12 HydroCad - Proposed POA 2 NOAA 24-hr D 10-Year Rainfall=5.22" Prepared by Anderson Consulting Services Printed 6/29/2024 Page 111 HydroCAD® 10.20-5a s/n 06666 © 2023 HydroCAD Software Solutions LLC Summary for Subcatchment 52S: Basin 10 - Perv Runoff = 2.19 cfs @ 12.18 hrs, Volume= Routed to Pond 41P : Basin 10 8,157 cf, Depth= 2.63" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-80.00 hrs, dt= 0.04 hrs NOAA 24-hr D 10-Year Rainfall=5.22" Area (sf) 7,626 29,609 37,235 37,235 Tc (min) 9.0 1.0 0.7 10.7 CN 80 74 75 Description >75% Grass cover, Good, HSG D >75% Grass cover, Good, HSG C Weighted Average 100.00% Pervious Area Length (feet) 59 Slope Velocity Capacity Description (ft/ft) (ft/sec) (cfs) 0.0200 0.11 Sheet Flow, Sheet Flow (A-B) Grass: Dense n= 0.240 P2= 3.47" Using McCuen-Spiess flow length 210 0.0480 3.53 Shallow Concentrated Flow, SCF (B-C) Unpaved Kv= 16.1 fps 110 2.50 Direct Entry, Pipe Flow (C-D) 379 Total Subcatchment 52S: Basin 10 - Perv Hydrograph Runoff 2.19 cfs Flow (cfs) 2 1 0 NOAA 24-hr D 10-Year Rainfall=5.22" Runoff Area=37,235 sf Runoff Volume=8,157 cf Runoff Depth=2.63" Flow Length=379' Tc=10.7 min CN=75 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 74 76 78 80 Time (hours)