ZB 22 13 2023 03 Drainage Statement

Date: 3/30/2023 Project: Proposed Popeyes & Fast Food Restaurant Project No: 1021-99-025 1904 Main Street, Lake Como, NJ 07719 Calculated By: DG (732) 974-0198 Checked By: MB Worksheet 3: Time of Concentration (T c ) Calculations Land Condition: Existing Drainage Area: Site • Sheet Flow : AB BC Smooth 1. Surface Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dense Grasses Surfaces 2. Manning's Roughness Coefficient, n . . . . . . . . . . . . . . . . . . . . . . 0.24 0.011 3. Flow Length, L { total L ≤ 100 ft } . . . . . . . . . . . . . . . . . . . . . . . 27.0 ft 73.0 ft 4. Two-Year 24-hour Rainfall, p 2 for . . . Essex County . . . . 3.44 in 3.44 in 5. Land Slope, s (ft/ft) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.074 ft/ft 0.041 ft/ft 0.007 (n L ) 0.8 6. Travel Time, T t = . . . . . . . . . . . . . . . . . .0.048 . . . . .hr + 0.011 hr + 0.000 hr = 0.059 hr p 2 0.5 s 0.4 • Shallow Concentrated Flow : CD 7. Surface

0.059 hr p 2 0.5 s 0.4 • Shallow Concentrated Flow : CD 7. Surface Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Paved 8. Flow Length, L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96.0 ft 9. Watercourse Slope, s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.047 ft/ft 10. Average velocity, V { see Figure 3.1) . . . . . . . . . . . . . . . . . . . . . . 4.41 ft/s 11. Travel Time, T t = L . . . . . . . . . . . . . . . . . .0.006 . . . . .hr + 0.000 hr + 0.000 hr = 0.006 hr 3600 V • Channel Flow : DE EF 12. Pipe Diameter, D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 in 10 in 13. Cross-Sectional Flow Area, A . . . . . . . . . . . . . . . . . . . . . . . . . 0.087 sf 0.545 sf 14. Wetted Perimeter, p w . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 ft 2.6 ft 15. Hydraulic Radius, r = A / p w . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 ft 0.2 ft 16. Channel Slope, s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.037 ft/ft 0.138 ft/ft 17. Pipe Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PVC PVC 18. Manning's Roughness Coefficient, n . . . . . . . . . . . . . . . . . . . . . 0.010 0.010 1.49 r 2/3 s 1/2 19. Velocity, V = . . . . . . . . . . . . . . . . . . . .5.47 . ft/s 19.45 ft/s

. . . . . . . . . . . . .5.47 . ft/s 19.45 ft/s n 20. Flow Length, L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50.0 21.0 21. Travel Time, T t = L . . . . . . . . . . . . . . . . . .0.003 . . . . .hr . . . +. . . 0.000 . . . . . hr . . . .+ 0.000 hr = 0.003 hr 3600 V 22. Watershed or subarea Time of Concentration, T c { add T t in steps 6, 11 and 21 } . . . . . . . . . . . . . . . . . . . . . . . . . 0.068 hr 4.1 min