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

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A Hyd. No. 45 Hydrograph Type = Junction Peak Flow = 22.69 cfs Storm Frequency = 100-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 80,053 cuft Inflow Hydrographs Total Contrib. Area = 0.0 ac Qp = 22.69 cfs 26 25 24 23 22 21 20 19 18 17 16 15 14 Q (cfs) 13 12 11 10 9 8 7 6 5 4 3 2 1 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Time (hrs) PR-2A-D PR-2A-U PR-2A

PR-2B-DISTURBED WATERSHED

Project: Eagle Rock Avenue By: TEG Date: 10/21/2025 Location: West Orange, NJ Checked By: MJV Date Checked: 10/21/2025 Circle One: Present Developed Future Proposed Watershed PR-2B-D - Impervious Circle One: Tc Tt through subarea Include a map, schematic, or description of flow segments. Sheet Flow (Applicable to Tc Only) Segment ID 1 Smooth Surfaces 1. Surface Description (NEH table 15-1) 2. Manning's Roughness Coeff., n (NEH table 15-1) 0.011 3. Design Flow Length, Ldes (Total Ldes < 100 ft) ft 100 4. Two-year 24-hr rainfall, P2 in 4.08 5. Land Slope, s ft/ft 0.074 6. McCuen-Spiess Limit, Lmcs (max. 100 ft) Lmcs = (100 s0.5)/n ft 100 7. Compute Tt 0.007 (nLdes)0.8 hr 0.011 + + Tt = 0.5 0.4 P2 s Sheet Flow Sub-Total 0.011 hours Shallow Concentrated Flow Segment ID 2 Pavement 8. Surface Description 9. Flow Length, L ft 155 10. Watercourse Slope, s ft/ft 0.040 11. Average Velocity, V (NEH table 15-3) ft/s 4.06 12. Compute Tt L hr 0.011 + +

ft/s 4.06 12. Compute Tt L hr 0.011 + + Tt = 3600 V Shallow Conc. Flow Sub-Total 0.011 hours Channel Flow Segment ID 13. Flow Length, L ft 14. Cross Sectional flow area, a ft2 15. Wetted Perimeter, Pw ft 16. Hydraulic Radius, r r = a / Pw ft 17. Channel Slope, s ft/ft 18. Manning's Roughness Coeff., n 19. Velocity, V V = (1.49 r2/3 s1/2 ) / n ft/s 20. Compute Tt L hr + + Tt = 3600 V Channel Flow Sub-Total 0.000 hours Watershed or subarea Tc or Tt Total Tc (hours) = 0.021 hours (Add Sub-Total Tt from prior steps) Software Limitations Require Minimum Tc = 2 minutes \\langan.com\data\PAR\data8\101049801\Project Data\_Discipline\Site Civil\Stormwater\Time of Concentration Calcs\Proposed Tc Calcs\Future Proposed TC PR-2B-D Impervious v1.4

Project: Eagle Rock Avenue By: TEG Date: 10/21/2025 Location: West Orange, NJ Checked By: MJV Date Checked: 10/21/2025 Circle One: Present Developed Future Proposed Watershed PR-2B-D - Pervious 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 Dense Grasses Smooth Surfaces 1. Surface Description (NEH table 15-1) 2. Manning's Roughness Coeff., n (NEH table 15-1) 0.24 0.011 3. Design Flow Length, Ldes (Total Ldes < 100 ft) ft 34 55 4. Two-year 24-hr rainfall, P2 in 4.08 4.08 5. Land Slope, s ft/ft 0.072 0.037 6. McCuen-Spiess Limit, Lmcs (max. 100 ft) Lmcs = (100 s0.5)/n ft 100 100 7. Compute Tt 0.007 (nLdes)0.8 hr 0.053 + 0.009 + Tt = 0.5 0.4 P2 s Sheet Flow Sub-Total 0.062 hours Shallow Concentrated Flow Segment ID 3 Pavement 8. Surface Description 9. Flow Length, L ft 41 10. Watercourse Slope, s ft/ft 0.020 11. Average Velocity, V (NEH table 15-3) ft/s 2.87 12. Compute Tt L

ft/ft 0.020 11. Average Velocity, V (NEH table 15-3) ft/s 2.87 12. Compute Tt L hr 0.004 + + Tt = 3600 V Shallow Conc. Flow Sub-Total 0.004 hours Channel Flow Segment ID 13. Flow Length, L ft 14. Cross Sectional flow area, a ft2 15. Wetted Perimeter, Pw ft 16. Hydraulic Radius, r r = a / Pw ft 17. Channel Slope, s ft/ft 18. Manning's Roughness Coeff., n 19. Velocity, V V = (1.49 r2/3 s1/2 ) / n ft/s 20. Compute Tt L hr + + Tt = 3600 V Channel Flow Sub-Total 0.000 hours Watershed or subarea Tc or Tt Total Tc (hours) = 0.066 hours (Add Sub-Total Tt from prior steps) Total Tc (minutes) = 4 minutes \\langan.com\data\PAR\data8\101049801\Project Data\_Discipline\Site Civil\Stormwater\Time of Concentration Calcs\Proposed Tc Calcs\Future Proposed TC PR-2B-D Pervious v1.4

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2B-D Open Space D Hyd. No. 48 Hydrograph Type = NRCS Runoff Peak Flow = 0.081 cfs Storm Frequency = 2-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 230 cuft Drainage Area = 0.03 ac Curve Number = 80.00 Tc Method = User Time of Conc. (Tc) = 4.0 min Total Rainfall = 4.08 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.081 cfs 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 Q (cfs) 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Time (hrs)

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2B-D Impervious Hyd. No. 49 Hydrograph Type = NRCS Runoff Peak Flow = 1.479 cfs Storm Frequency = 2-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 4,841 cuft Drainage Area = 0.37 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 2.0 min Total Rainfall = 4.08 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 1.479 cfs 2 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 Q (cfs) 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Time (hrs)

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2B-D Hyd. No. 50 Hydrograph Type = Junction Peak Flow = 1.559 cfs Storm Frequency = 2-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 5,071 cuft Inflow Hydrographs = 48, 49 Total Contrib. Area = 0.4 ac Qp = 1.559 cfs 2 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 Q (cfs) 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Time (hrs) PR-2B-D Open Space D PR-2B-D Impervious PR-2B-D

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2B-D Open Space D Hyd. No. 48 Hydrograph Type = NRCS Runoff Peak Flow = 0.154 cfs Storm Frequency = 10-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 448 cuft Drainage Area = 0.03 ac Curve Number = 80.00 Tc Method = User Time of Conc. (Tc) = 4.0 min Total Rainfall = 6.37 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.154 cfs 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 Q (cfs) 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Time (hrs)