12 2026 02 12 Crestmont CC Stormwater Management Report

Total Tc (minutes) = 17 minutes \\langan.com\data\PAR\data8\101049801\Project Data\_Discipline\Site Civil\Stormwater\Time of Concentration Calcs\Proposed Tc Calcs\Current Proposed TCs\Current Proposed TC PR-2A-U Pervious v1.2

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 = 0.173 cfs Storm Frequency = 2-yr Time to Peak = 12.25 hrs Time Interval = 1 min Runoff Volume = 783 cuft Drainage Area = 0.18 ac Curve Number = 74.00 Tc Method = User Time of Conc. (Tc) = 17.0 min Total Rainfall = 3.46 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.173 cfs 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 (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 = 0.135 cfs Storm Frequency = 2-yr Time to Peak = 12.25 hrs Time Interval = 1 min Runoff Volume = 635 cuft Drainage Area = 0.18 ac Curve Number = 70.00 Tc Method = User Time of Conc. (Tc) = 17.0 min Total Rainfall = 3.46 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.135 cfs 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)

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 = 2.299 cfs Storm Frequency = 2-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 7,467 cuft Drainage Area = 0.68 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 2.0 min Total Rainfall = 3.46 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 2.299 cfs 3 2 Q (cfs) 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 = 2.492 cfs Storm Frequency = 2-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 8,885 cuft Inflow Hydrographs = 39, 40, 41 Total Contrib. Area = 1.04 ac Qp = 2.492 cfs 3 2 Q (cfs) 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 = 0.393 cfs Storm Frequency = 10-yr Time to Peak = 12.23 hrs Time Interval = 1 min Runoff Volume = 1,725 cuft Drainage Area = 0.18 ac Curve Number = 74.00 Tc Method = User Time of Conc. (Tc) = 17.0 min Total Rainfall = 5.38 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.393 cfs 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 Q (cfs) 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 Woods C Hyd. No. 40 Hydrograph Type = NRCS Runoff Peak Flow = 0.339 cfs Storm Frequency = 10-yr Time to Peak = 12.23 hrs Time Interval = 1 min Runoff Volume = 1,500 cuft Drainage Area = 0.18 ac Curve Number = 70.00 Tc Method = User Time of Conc. (Tc) = 17.0 min Total Rainfall = 5.38 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 0.339 cfs 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 Q (cfs) 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 = 3.594 cfs Storm Frequency = 10-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 11,901 cuft Drainage Area = 0.68 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 2.0 min Total Rainfall = 5.38 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 3.594 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-2A-U Hyd. No. 42 Hydrograph Type = Junction Peak Flow = 4.094 cfs Storm Frequency = 10-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 15,126 cuft Inflow Hydrographs = 39, 40, 41 Total Contrib. Area = 1.04 ac Qp = 4.094 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-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 = 0.559 cfs Storm Frequency = 25-yr Time to Peak = 12.23 hrs Time Interval = 1 min Runoff Volume = 2,454 cuft Drainage Area = 0.18 ac Curve Number = 74.00 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 = 0.559 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)