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

Hydrograph Report File: Eagle Rock Existing (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 EX-1-U Hyd. No. 16 Hydrograph Type = Junction Peak Flow = 11.65 cfs Storm Frequency = 2-yr Time to Peak = 12.12 hrs Time Interval = 1 min Hydrograph Volume = 43,863 cuft Inflow Hydrographs = 13, 14, 15 Total Contrib. Area = 5.0 ac Qp = 11.65 cfs 13 12 11 10 9 8 7 Q (cfs) 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) EX-1-U Open Space C EX-1-U Woods C EX-1-U Impervious EX-1-U

Hydrograph Report File: Eagle Rock Existing (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 EX-1-U Open Space C Hyd. No. 13 Hydrograph Type = NRCS Runoff Peak Flow = 3.376 cfs Storm Frequency = 10-yr Time to Peak = 12.18 hrs Time Interval = 1 min Runoff Volume = 12,980 cuft Drainage Area = 1.36 ac Curve Number = 74.00 Tc Method = User Time of Conc. (Tc) = 12.0 min Total Rainfall = 5.38 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 3.376 cfs 4 3 Q (cfs) 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)

Hydrograph Report File: Eagle Rock Existing (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 EX-1-U Woods C Hyd. No. 14 Hydrograph Type = NRCS Runoff Peak Flow = 1.502 cfs Storm Frequency = 10-yr Time to Peak = 12.18 hrs Time Interval = 1 min Runoff Volume = 5,809 cuft Drainage Area = 0.7 ac Curve Number = 70.00 Tc Method = User Time of Conc. (Tc) = 12.0 min Total Rainfall = 5.38 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 1.502 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 Existing (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 EX-1-U Impervious Hyd. No. 15 Hydrograph Type = NRCS Runoff Peak Flow = 15.51 cfs Storm Frequency = 10-yr Time to Peak = 12.12 hrs Time Interval = 1 min Runoff Volume = 56,598 cuft Drainage Area = 2.94 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 5.0 min Total Rainfall = 5.38 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 15.51 cfs 17 16 15 14 13 12 11 10 9 Q (cfs) 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)

Hydrograph Report File: Eagle Rock Existing (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 EX-1-U Hyd. No. 16 Hydrograph Type = Junction Peak Flow = 19.71 cfs Storm Frequency = 10-yr Time to Peak = 12.12 hrs Time Interval = 1 min Hydrograph Volume = 75,387 cuft Inflow Hydrographs = 13, 14, 15 Total Contrib. Area = 5.0 ac Qp = 19.71 cfs 22 21 20 19 18 17 16 15 14 13 12 Q (cfs) 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) EX-1-U Open Space C EX-1-U Woods C EX-1-U Impervious EX-1-U

Hydrograph Report File: Eagle Rock Existing (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 EX-1-U Open Space C Hyd. No. 13 Hydrograph Type = NRCS Runoff Peak Flow = 7.542 cfs Storm Frequency = 100-yr Time to Peak = 12.18 hrs Time Interval = 1 min Runoff Volume = 29,392 cuft Drainage Area = 1.36 ac Curve Number = 74.00 Tc Method = User Time of Conc. (Tc) = 12.0 min Total Rainfall = 9.24 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 7.542 cfs 8 7 6 5 Q (cfs) 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)

Hydrograph Report File: Eagle Rock Existing (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 EX-1-U Woods C Hyd. No. 14 Hydrograph Type = NRCS Runoff Peak Flow = 3.591 cfs Storm Frequency = 100-yr Time to Peak = 12.18 hrs Time Interval = 1 min Runoff Volume = 13,875 cuft Drainage Area = 0.7 ac Curve Number = 70.00 Tc Method = User Time of Conc. (Tc) = 12.0 min Total Rainfall = 9.24 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 3.591 cfs 4 3 Q (cfs) 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)

Hydrograph Report File: Eagle Rock Existing (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 EX-1-U Impervious Hyd. No. 15 Hydrograph Type = NRCS Runoff Peak Flow = 26.72 cfs Storm Frequency = 100-yr Time to Peak = 12.12 hrs Time Interval = 1 min Runoff Volume = 99,046 cuft Drainage Area = 2.94 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 5.0 min Total Rainfall = 9.24 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 26.72 cfs 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 Q (cfs) 15 14 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)

Hydrograph Report File: Eagle Rock Existing (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 EX-1-U Hyd. No. 16 Hydrograph Type = Junction Peak Flow = 36.55 cfs Storm Frequency = 100-yr Time to Peak = 12.12 hrs Time Interval = 1 min Hydrograph Volume = 142,313 cuft Inflow Hydrographs = 13, 14, 15 Total Contrib. Area = 5.0 ac Qp = 36.55 cfs 42 40 38 36 34 32 30 28 26 24 22 Q (cfs) 20 18 16 14 12 10 8 6 4 2 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) EX-1-U Open Space C EX-1-U Woods C EX-1-U Impervious EX-1-U

TOTAL EXISTING FLOW TO POA-1