ZB 22 13 2023 03 Drainage Statement

TIME OF CONCENTRATION (TC) CALCULATIONS

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

Date: 3/30/2023 Project: Proposed Popeyes & Sonic Restaurant Project No: 1021-99-025 1904 Main Street, Lake Como, NJ 07719 Calculated By: JD (732) 974-0198 Checked By: DG/MB Worksheet 3: Time of Concentration (T c ) Calculations Land Condition: Proposed Drainage Area: Site • Sheet Flow : AB BC Short Grass, Smooth 1. Surface Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Prairie . Surfaces 2. Manning's Roughness Coefficient, n . . . . . . . . . . . . . . . . . . . .0.15 .. 0.011 3. Flow Length, L { total L ≤ 100 ft } . . . . . . . . . . . . . . . . . . . . .52.0 . . ft 32.0 ft 4. Two-Year 24-hour Rainfall, p 2 for . . .Essex County. . . . 3.44 in 3.44 in 3.44 in 5. Land Slope, s (ft/ft) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ft/ft 0.065 0.030 ft/ft 0.007 (n L ) 0.8 6. Travel Time, T t = . . . . . . . . . . . . . . . .0.058 . . . . .hr .. + 0.007 hr + 0.000 hr = 0.065 hr

. . . . .hr .. + 0.007 hr + 0.000 hr = 0.065 hr p 2 0.5 s 0.4 • Shallow Concentrated Flow : 7. Surface Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8. Flow Length, L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9. Watercourse Slope, s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10. Average velocity, V { see Figure 3.1) . . . . . . . . . . . . . . . . . . . . . . 11. Travel Time, T t = L . . . . . . . . . . . . . . . .0.000 . . . . .hr .. + 0.000 hr + 0.000 hr = 0.000 hr 3600 V • Channel Flow : CD DE EF 12. Pipe Diameter, D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 in 12 in 15 in 13. Cross-Sectional Flow Area, A . . . . . . . . . . . . . . . . . . . . . . . 0.785 .. sf 0.785 sf 1.227 sf 14. Wetted Perimeter, p w . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1 ft 3.1 ft 3.9 ft 15. Hydraulic Radius, r = A / p w . . . . . . . . . . . . . . . . . . . . . . . . . 0.3 . ft 0.3 ft 0.3 ft 16. Channel Slope, s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.021 .. ft/ft 0.025 ft/ft 0.049 ft/ft 17. Pipe Material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RCP RCP RCP 18. Manning's Roughness Coefficient, n . . . . . . . . . . . . . . . . . . . 0.013 .. 0.013 0.013 1.49 r 2/3 s 1/2 19. Velocity, V = . . . . . . . . . . . . . . . . . .6.59

0.013 0.013 1.49 r 2/3 s 1/2 19. Velocity, V = . . . . . . . . . . . . . . . . . .6.59 . . . ft/s 7.19 ft/s 11.68 ft/s n 20. Flow Length, L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93.0.... 55.0 39.0 21. Travel Time, T t = L . . . . . . . . . . . . . . . .0.004 . . . . .hr . . .+ . . . 0.002 . . . . . hr . . . .+. . 0.001 hr = 0.007 hr 3600 V 22. Watershed or subarea Time of Concentration, T c { add T t in steps 6, 11 and 21 } . . . . . . . . . . . . . . . . . . . . . . . . . 0.072 hr 4.3 min 1

RUNOFF CURVE NUMBER (CN) CALCULATIONS – EXISTING

Project: Proposed Popeye's & Fast Food Restaurant Computed By: DG Job #: 1021-99-025 Checked By: MB Location: West Orange, NJ Date: 3/30/2023 Drainage Area Impervious Impervious Curve HSG B - HSG B - Curve HSG C - HSG C - Curve Avg. Perv. Total Total Area TC (Min.) Area (acre) Area (sf) Number Open Open Number Open Open Number Curve Pervious (acres) (CN) Used Space Area Space Area (CN) Used Space Area Space Area (CN) Used Number Area (acre) (sf) (acre) (sf) (acres) Study Area Site 0.84 36,782 98 0.07 3,045 61 0.14 5,966 74 70 0.21 1.05 4 Total 0.84 36,782 0.07 3,045 0.14 5,966 0.21 1.05 Per County Soil Survey - URBONB HSG B Soil Urban Land, Boonton substratum, 0 to 8 percent slopes Per County Soil Survey - BouC HSG C Soil Boonton - Urban Land, Boonton substratum complex, 8 to 15 percent slopes Runoff Curve Number (CN) Runoff Curve Number (CN) Description (HSG B) (HSG C) Impervious Surface 98 98 Open Space (lawn) (good) 61 74

RUNOFF CURVE NUMBER (CN) CALCULATIONS – PROPOSED