V4 11 Stormwater Report Rev 3 1 26 2023

Project #: 20-0265 Green Roof Calculations Project: Daughters of Israel County: Essex Depth of Media (In) 4 *Based on 20% 1-7mm pumice, Available water capacity for Runoff retention * 0.231 60% 4-10mm pumic, 20% Drainage Layer Depth 0 composted pine bark fines (BMP Manual) Drainage Layer Field Capacity 0 Area of Area of Total Rainfall (IN) Green Sv (SF) Roof (SF) Roof (SF) 2 YR 10 YR 100 YR Phase I 44933 4492 345.9 3.44 5.22 8.66 Phase II & III 76224 18366 1414.2 Volume Without Green Roof (CF) Volume With Green Roof (CF) 2 YR 10 YR 100 YR 2 YR 10 YR 100 YR P1 11,240 17,466 29,513 P1 10,894 17,120 29,167 P2/3 19,097 29,675 50,144 P2/3 17,683 28,261 48,730 Q (CFS) Adjusted CN 2 YR 10 YR 100 YR 2 YR 10 YR 100 YR P1 2.91 4.57 7.79 P1 95 94 93 P2/3 2.78 4.45 7.67 P2/3 94 93 92