2026 02 12 Crestmont CC and Eagle Rock Ave Stormwater Management Report

ft 13 9. Watercourse Slope, s ft/ft 0.372 10. Average Velocity, V (NEH table 15-3) ft/s 9.85 11. Compute Tt L hr 0.000 + + Tt = 3600 V Shallow Conc. Flow Sub-Total 0.000 hours Channel Flow Segment ID 4 12. Flow Length, L ft 308 13. Cross Sectional flow area, a ft2 0.69 14. Wetted Perimeter, Pw ft 3.58 15. Hydraulic Radius, r r = a / Pw ft 0.19 16. Channel Slope, s ft/ft 0.010 17. Manning's Roughness Coeff., n 0.035 18. Velocity, V V = (1.49 r2/3 s1/2 ) / n ft/s 1.42 19. Compute Tt L hr 0.060 + + Tt = 3600 V Channel Flow Sub-Total 0.060 hours Watershed or subarea Tc or Tt Total Tc (hours) = 0.244 hours (Add Sub-Total Tt from prior steps) Total Tc (minutes) = 15 minutes \\langan.com\data\PAR\data8\101049801\Project Data\_Discipline\Site Civil\Stormwater\Time of Concentration Calcs\Inlet Area Tc Calcs\Current Proposed TC CB1-7 Pervious

ata8\101049801\Project Data\_Discipline\Site Civil\Stormwater\Time of Concentration Calcs\Inlet Area Tc Calcs\Current Proposed TC CB1-7 Pervious v1.2

CB1-13

Project: Eagle Rock Avenue By: TEG Date: 10/22/2025 Location: West Orange, NJ Checked By: MJV Date Checked: 10/22/2025 Circle One: Present Developed Inlet CB1-13 Circle One: Tc Tt through subarea Include a map, schematic, or description of flow segments. Sheet Flow (Applicable to Tc Only) Segment ID 1 2 Bermuda Grass Bermuda Grass 1. Surface Description (NEH table 15-1) 2. Manning's Roughness Coeff., n (NEH table 15-1) 0.40 0.40 3. Flow Length, L (total L < 100 ft) ft 28 72 4. Two-year 24-hr rainfall, P2 in 3.43 3.43 5. Land Slope, s ft/ft 0.357 0.035 6. Compute Tt 0.007 (nL)0.8 hr 0.039 + 0.213 + Tt = P20.5s0.4 Sheet Flow Sub-Total 0.253 hours Shallow Concentrated Flow Segment ID 3 4 Pavement Pavement 7. Surface Description 8. Flow Length, L ft 70 140 9. Watercourse Slope, s ft/ft 0.137 0.000 10. Average Velocity, V (NEH table 15-3) ft/s 7.53

ft/ft 0.137 0.000 10. Average Velocity, V (NEH table 15-3) ft/s 7.53 0.00 11. Compute Tt L hr 0.003 + + Tt = 3600 V Shallow Conc. Flow Sub-Total 0.003 hours Channel Flow Segment ID 12. Flow Length, L ft 13. Cross Sectional flow area, a ft2 14. Wetted Perimeter, Pw ft 15. Hydraulic Radius, r r = a / Pw ft 16. Channel Slope, s ft/ft 17. Manning's Roughness Coeff., n 18. Velocity, V V = (1.49 r2/3 s1/2 ) / n ft/s 19. Compute Tt L hr + + Tt = 3600 V Channel Flow Sub-Total 0.000 hours Watershed or subarea Tc or Tt Total Tc (hours) = 0.255 hours (Add Sub-Total Tt from prior steps) Total Tc (minutes) = 15 minutes \\langan.com\data\PAR\data8\101049801\Project Data\_Discipline\Site Civil\Stormwater\Time of Concentration Calcs\Inlet Area Tc Calcs\Current Proposed TC CB1-13 Pervious v1.2

= = SUPPORTING BASIN OUTFLOW HYDROGRAPH REPORTS

SSBB-1

Hydrograph Report File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-22-2025 PR-1A Routing Hyd. No. 11 Hydrograph Type = Pond Route Peak Flow = 3.069 cfs Storm Frequency = 25-yr Time to Peak = 12.27 hrs Time Interval = 1 min Hydrograph Volume = 26,002 cuft Inflow Hydrograph = 10 - PR-1A Total Max. Elevation = 536.03 ft Pond Name = SSBB-1 Max. Storage = 10,002 cuft Pond Routing by Storage Indication Method Center of mass detention time = 1.46 hrs Hydrograph Discharge Table Time Outflow Time Outflow Time Outflow Time Outflow Time Outflow (hrs) (cfs) (hrs) (cfs) (hrs) (cfs) (hrs) (cfs) (hrs) (cfs) 9.63 0.031 10.05 0.106 10.47 0.219 10.88 0.343 11.30 0.547 9.65 0.034 10.07 0.111 10.48 0.223 10.90 0.350 11.32 0.557 9.67 0.038 10.08 0.116 10.50 0.227 10.92 0.357 11.33 0.566 9.68 0.041 10.10 0.121 10.52 0.230 10.93 0.364 11.35 0.575 9.70 0.044 10.12 0.126 10.53 0.234 10.95 0.371 11.37 0.584 9.72 0.047 10.13 0.131 10.55 0.239 10.97 0.378 11.38 0.593 9.73

0.371 11.37 0.584 9.72 0.047 10.13 0.131 10.55 0.239 10.97 0.378 11.38 0.593 9.73 0.050 10.15 0.136 10.57 0.243 10.98 0.385 11.40 0.602 9.75 0.053 10.17 0.141 10.58 0.247 11.00 0.392 11.42 0.612 9.77 0.056 10.18 0.146 10.60 0.251 11.02 0.399 11.43 0.621 9.78 0.059 10.20 0.150 10.62 0.256 11.03 0.406 11.45 0.631 9.80 0.062 10.22 0.155 10.63 0.260 11.05 0.414 11.47 0.641 9.82 0.065 10.23 0.159 10.65 0.265 11.07 0.422 11.48 0.651 9.83 0.068 10.25 0.164 10.67 0.269 11.08 0.430 11.50 0.661 9.85 0.071 10.27 0.169 10.68 0.274 11.10 0.438 11.52 0.672 9.87 0.074 10.28 0.173 10.70 0.279 11.12 0.446 11.53 0.684 9.88 0.077 10.30 0.177 10.72 0.283 11.13 0.454 11.55 0.699 9.90 0.080 10.32 0.182 10.73 0.288 11.15 0.463 11.57 0.715 9.92 0.083 10.33 0.186 10.75 0.293 11.17 0.472 11.58 0.731 9.93 0.086 10.35 0.190 10.77 0.298 11.18 0.481 11.60 0.748 9.95 0.089 10.37 0.195 10.78 0.303 11.20 0.489 11.62 0.764 9.97 0.092 10.38 0.199 10.80 0.310 11.22 0.498 11.63 0.779 9.98 0.095 10.40 0.203 10.82 0.316 11.23 0.508

0.199 10.80 0.310 11.22 0.498 11.63 0.779 9.98 0.095 10.40 0.203 10.82 0.316 11.23 0.508 11.65 0.791 10.00 0.098 10.42 0.207 10.83 0.323 11.25 0.517 11.67 0.803 10.02 0.101 10.43 0.211 10.85 0.330 11.27 0.527 11.68 0.815 10.03 0.103 10.45 0.215 10.87 0.336 11.28 0.537 11.70 0.827 Printed values > 1% of Qpeak. nth-point print interval = 1