12 2026 02 12 Crestmont CC Stormwater Management Report

Hydrograph Report File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-1B-U Open Space C Hyd. No. 15 Hydrograph Type = NRCS Runoff Peak Flow = 0.986 cfs Storm Frequency = 25-yr Time to Peak = 12.20 hrs Time Interval = 1 min Runoff Volume = 3,999 cuft Drainage Area = 0.29 ac Curve Number = 74.00 Tc Method = User Time of Conc. (Tc) = 14.0 min Total Rainfall = 6.72 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.986 cfs 1 0.95 0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 Q (cfs) 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 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 (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-1B-U Woods C Hyd. No. 16 Hydrograph Type = NRCS Runoff Peak Flow = 1.881 cfs Storm Frequency = 25-yr Time to Peak = 12.20 hrs Time Interval = 1 min Runoff Volume = 7,623 cuft Drainage Area = 0.62 ac Curve Number = 70.00 Tc Method = User Time of Conc. (Tc) = 14.0 min Total Rainfall = 6.72 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 1.881 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 (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-1B-U Impervious Hyd. No. 17 Hydrograph Type = NRCS Runoff Peak Flow = 7.010 cfs Storm Frequency = 25-yr Time to Peak = 12.12 hrs Time Interval = 1 min Runoff Volume = 27,067 cuft Drainage Area = 1.18 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 7.0 min Total Rainfall = 6.72 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 7.010 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 Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-1B-U Hyd. No. 18 Hydrograph Type = Junction Peak Flow = 9.525 cfs Storm Frequency = 25-yr Time to Peak = 12.13 hrs Time Interval = 1 min Hydrograph Volume = 38,689 cuft Inflow Hydrographs = 15, 16, 17 Total Contrib. Area = 2.09 ac Qp = 9.525 cfs 10 9 8 7 6 Q (cfs) 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-1B-U Open Space C PR-1B-U Woods C PR-1B-U Impervious PR-1B-U

Hydrograph Report File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-1B-U Open Space C Hyd. No. 15 Hydrograph Type = NRCS Runoff Peak Flow = 1.552 cfs Storm Frequency = 100-yr Time to Peak = 12.20 hrs Time Interval = 1 min Runoff Volume = 6,367 cuft Drainage Area = 0.29 ac Curve Number = 74.00 Tc Method = User Time of Conc. (Tc) = 14.0 min Total Rainfall = 9.24 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 1.552 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 (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-1B-U Woods C Hyd. No. 16 Hydrograph Type = NRCS Runoff Peak Flow = 3.068 cfs Storm Frequency = 100-yr Time to Peak = 12.20 hrs Time Interval = 1 min Runoff Volume = 12,484 cuft Drainage Area = 0.62 ac Curve Number = 70.00 Tc Method = User Time of Conc. (Tc) = 14.0 min Total Rainfall = 9.24 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 3.068 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 Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-1B-U Impervious Hyd. No. 17 Hydrograph Type = NRCS Runoff Peak Flow = 9.653 cfs Storm Frequency = 100-yr Time to Peak = 12.12 hrs Time Interval = 1 min Runoff Volume = 37,585 cuft Drainage Area = 1.18 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 7.0 min Total Rainfall = 9.24 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 9.653 cfs 11 10 9 8 7 6 Q (cfs) 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 Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-1B-U Hyd. No. 18 Hydrograph Type = Junction Peak Flow = 13.76 cfs Storm Frequency = 100-yr Time to Peak = 12.13 hrs Time Interval = 1 min Hydrograph Volume = 56,436 cuft Inflow Hydrographs = 15, 16, 17 Total Contrib. Area = 2.09 ac Qp = 13.76 cfs 15 14 13 12 11 10 9 8 Q (cfs) 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-1B-U Open Space C PR-1B-U Woods C PR-1B-U Impervious PR-1B-U

= = PR-1B WATERSHED (COMBINED PROPOSED FLOW TO SWALE 1)

Hydrograph Report File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-1B (Swale) Hyd. No. 21 Hydrograph Type = Junction Peak Flow = 4.925 cfs Storm Frequency = 2-yr Time to Peak = 12.13 hrs Time Interval = 1 min Hydrograph Volume = 19,068 cuft Inflow Hydrographs = 13 Total Contrib. Area = 0.35 ac Qp = 4.925 cfs 5 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) PR-1B-D PR-1B-U PR-1B (Swale)