V4 11 Stormwater Report Rev 3 1 26 2023

Time of Concentration Calculations Project #: 20-0265 Pre-Development Project: Daughters of Israel Post-Development County: Essex Drainage Area: DA-4 Sheet Flow Segment 1 Segment 2 Segment 3 Woods, Light Woods, Light Surface Description (Table 3-1) Underbrush Underbrush Manning's Roughness Coeff., n (Table 3-1) 0.4 0.4 - Flow Length, L (total ≤ 100 ft) 48 52 Two-Year 24-Hour Rainfall, P2 3.44 3.44 3.44 Land Slope, s (ft/ft) 0.08 0.19 Tt 6.61 4.99 - 11.60 Shallow Concentrated Flow Segment 1 Segment 2 Segment 3 Surface Description Unpaved Unpaved paved Flow Length, L 52 117 270 Watercourse Slope, s 0.06 0.24 0.01 Average Velocity 3.9 7.8 2.0 Tt 0.22 0.25 2.23 2.70 Channel Flow Segment 1 Segment 2 Segment 3 Cross Sectional Flow Area, a Wetted Perimeter, Pw Hydraulic Radius, r - - - Channel Slope, s Manning's Roughness Description Manning's Roughness - - - Velocity - - - Flow Length Tt - - - 0.00 14.30