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

ft/s 4.73 12. Compute Tt L hr 0.015 + + Tt = 3600 V Shallow Conc. Flow Sub-Total 0.015 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) = 0.026 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-U 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-U - 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 Dense Grasses 1. Surface Description (NEH table 15-1) 2. Manning's Roughness Coeff., n (NEH table 15-1) 0.24 3. Design Flow Length, Ldes (Total Ldes < 100 ft) ft 23 4. Two-year 24-hr rainfall, P2 in 4.08 5. Land Slope, s ft/ft 0.130 6. McCuen-Spiess Limit, Lmcs (max. 100 ft) Lmcs = (100 s0.5)/n ft 100 7. Compute Tt 0.007 (nLdes)0.8 hr 0.031 + + Tt = 0.5 0.4 P2 s Sheet Flow Sub-Total 0.031 hours Shallow Concentrated Flow Segment ID 2 Pavement 8. Surface Description 9. Flow Length, L ft 231 10. Watercourse Slope, s ft/ft 0.048 11. Average Velocity, V (NEH table 15-3) ft/s 4.45 12. Compute Tt L hr 0.014 + +

ft/s 4.45 12. Compute Tt L hr 0.014 + + Tt = 3600 V Shallow Conc. Flow Sub-Total 0.014 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) = 0.045 hours (Add Sub-Total Tt from prior steps) Total Tc (minutes) = 3 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-U Pervious v1.4

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2B-U Open Space C Hyd. No. 52 Hydrograph Type = NRCS Runoff Peak Flow = 0.021 cfs Storm Frequency = 2-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 56.3 cuft Drainage Area = 0.01 ac Curve Number = 74.00 Tc Method = User Time of Conc. (Tc) = 3.0 min Total Rainfall = 4.08 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.021 cfs 0.021 0.02 0.019 0.018 0.017 0.016 0.015 0.014 0.013 0.012 0.011 Q (cfs) 0.01 0.009 0.008 0.007 0.006 0.005 0.004 0.003 0.002 0.001 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-U Impervious Hyd. No. 53 Hydrograph Type = NRCS Runoff Peak Flow = 0.120 cfs Storm Frequency = 2-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 393 cuft Drainage Area = 0.03 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 = 0.120 cfs 0.12 0.11 0.1 0.09 0.08 0.07 Q (cfs) 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)

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2B-U Hyd. No. 54 Hydrograph Type = Junction Peak Flow = 0.141 cfs Storm Frequency = 2-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 449 cuft Inflow Hydrographs = 52, 53 Total Contrib. Area = 0.04 ac Qp = 0.141 cfs 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 Q (cfs) 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) PR-2B-U Open Space C PR-2B-U Impervious PR-2B-U

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2B-U Open Space C Hyd. No. 52 Hydrograph Type = NRCS Runoff Peak Flow = 0.043 cfs Storm Frequency = 10-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 119 cuft Drainage Area = 0.01 ac Curve Number = 74.00 Tc Method = User Time of Conc. (Tc) = 3.0 min Total Rainfall = 6.37 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.043 cfs 0.044 0.042 0.04 0.038 0.036 0.034 0.032 0.03 0.028 0.026 0.024 Q (cfs) 0.022 0.02 0.018 0.016 0.014 0.012 0.01 0.008 0.006 0.004 0.002 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-U Impervious Hyd. No. 53 Hydrograph Type = NRCS Runoff Peak Flow = 0.188 cfs Storm Frequency = 10-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 626 cuft Drainage Area = 0.03 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 2.0 min Total Rainfall = 6.37 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.188 cfs 0.19 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 Q (cfs) 0.09 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)

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2B-U Hyd. No. 54 Hydrograph Type = Junction Peak Flow = 0.231 cfs Storm Frequency = 10-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 745 cuft Inflow Hydrographs = 52, 53 Total Contrib. Area = 0.04 ac Qp = 0.231 cfs 0.24 0.23 0.22 0.21 0.2 0.19 0.18 0.17 0.16 0.15 0.14 0.13 Q (cfs) 0.12 0.11 0.1 0.09 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) PR-2B-U Open Space C PR-2B-U Impervious PR-2B-U

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2B-U Open Space C Hyd. No. 52 Hydrograph Type = NRCS Runoff Peak Flow = 0.062 cfs Storm Frequency = 25-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 172 cuft Drainage Area = 0.01 ac Curve Number = 74.00 Tc Method = User Time of Conc. (Tc) = 3.0 min Total Rainfall = 8.13 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.062 cfs 0.06 0.056 0.052 0.048 0.044 0.04 0.036 0.032 Q (cfs) 0.028 0.024 0.02 0.016 0.012 0.008 0.004 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)