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

Hydrograph Report File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-U Woods C Hyd. No. 40 Hydrograph Type = NRCS Runoff Peak Flow = 0.498 cfs Storm Frequency = 25-yr Time to Peak = 12.23 hrs Time Interval = 1 min Runoff Volume = 2,188 cuft Drainage Area = 0.18 ac Curve Number = 70.00 Tc Method = User Time of Conc. (Tc) = 17.0 min Total Rainfall = 6.72 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.498 cfs 0.5 0.48 0.46 0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 Q (cfs) 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 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-2A-U Impervious Hyd. No. 41 Hydrograph Type = NRCS Runoff Peak Flow = 4.496 cfs Storm Frequency = 25-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 14,998 cuft Drainage Area = 0.68 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 2.0 min Total Rainfall = 6.72 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 4.496 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)

Hydrograph Report File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-U Hyd. No. 42 Hydrograph Type = Junction Peak Flow = 5.236 cfs Storm Frequency = 25-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 19,640 cuft Inflow Hydrographs = 39, 40, 41 Total Contrib. Area = 1.04 ac Qp = 5.236 cfs 6 5 4 Q (cfs) 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-U Open Space C PR-2A-U Woods C PR-2A-U Impervious PR-2A-U

Hydrograph Report File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-U Open Space C Hyd. No. 39 Hydrograph Type = NRCS Runoff Peak Flow = 0.881 cfs Storm Frequency = 100-yr Time to Peak = 12.23 hrs Time Interval = 1 min Runoff Volume = 3,907 cuft Drainage Area = 0.18 ac Curve Number = 74.00 Tc Method = User Time of Conc. (Tc) = 17.0 min Total Rainfall = 9.24 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.881 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-2A-U Woods C Hyd. No. 40 Hydrograph Type = NRCS Runoff Peak Flow = 0.814 cfs Storm Frequency = 100-yr Time to Peak = 12.23 hrs Time Interval = 1 min Runoff Volume = 3,583 cuft Drainage Area = 0.18 ac Curve Number = 70.00 Tc Method = User Time of Conc. (Tc) = 17.0 min Total Rainfall = 9.24 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.814 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-2A-U Impervious Hyd. No. 41 Hydrograph Type = NRCS Runoff Peak Flow = 6.190 cfs Storm Frequency = 100-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 20,826 cuft Drainage Area = 0.68 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 2.0 min Total Rainfall = 9.24 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 6.190 cfs 7 6 5 4 Q (cfs) 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-2A-U Hyd. No. 42 Hydrograph Type = Junction Peak Flow = 7.407 cfs Storm Frequency = 100-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 28,316 cuft Inflow Hydrographs = 39, 40, 41 Total Contrib. Area = 1.04 ac Qp = 7.407 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) PR-2A-U Open Space C PR-2A-U Woods C PR-2A-U Impervious PR-2A-U

= = PR-2A WATERSHED (COMBINED PROPOSED FLOW TO SSBB-2)

Hydrograph Report File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A Hyd. No. 45 Hydrograph Type = Junction Peak Flow = 5.420 cfs Storm Frequency = 2-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 18,303 cuft Inflow Hydrographs Total Contrib. Area = 0.0 ac Qp = 5.420 cfs 6 5 4 Q (cfs) 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

Hydrograph Report File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A Hyd. No. 45 Hydrograph Type = Junction Peak Flow = 9.340 cfs Storm Frequency = 10-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 32,140 cuft Inflow Hydrographs Total Contrib. Area = 0.0 ac Qp = 9.340 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-2A-D PR-2A-U PR-2A