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

Total Tc (hours) = 0.093 hours (Add Sub-Total Tt from prior steps) Total Tc (minutes) = 6 minutes \\langan.com\data\PAR\data8\101049801\Project Data\_Discipline\Site Civil\Stormwater\Time of Concentration Calcs\Proposed Tc Calcs\Future Proposed TC PR-2A-D Pervious v1.4

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-D Open Space D Hyd. No. 35 Hydrograph Type = NRCS Runoff Peak Flow = 2.042 cfs Storm Frequency = 2-yr Time to Peak = 12.12 hrs Time Interval = 1 min Runoff Volume = 6,313 cuft Drainage Area = 0.8 ac Curve Number = 80.00 Tc Method = User Time of Conc. (Tc) = 6.0 min Total Rainfall = 4.08 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 2.042 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 (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-D Impervious Hyd. No. 36 Hydrograph Type = NRCS Runoff Peak Flow = 1.679 cfs Storm Frequency = 2-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 5,496 cuft Drainage Area = 0.42 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 = 1.679 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 (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-D Hyd. No. 37 Hydrograph Type = Junction Peak Flow = 3.665 cfs Storm Frequency = 2-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 11,808 cuft Inflow Hydrographs = 35, 36 Total Contrib. Area = 1.22 ac Qp = 3.665 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) PR-2A-D Open Space D PR-2A-D Impervious PR-2A-D

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-D Open Space D Hyd. No. 35 Hydrograph Type = NRCS Runoff Peak Flow = 3.918 cfs Storm Frequency = 10-yr Time to Peak = 12.12 hrs Time Interval = 1 min Runoff Volume = 12,329 cuft Drainage Area = 0.8 ac Curve Number = 80.00 Tc Method = User Time of Conc. (Tc) = 6.0 min Total Rainfall = 6.37 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 3.918 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 (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-D Impervious Hyd. No. 36 Hydrograph Type = NRCS Runoff Peak Flow = 2.631 cfs Storm Frequency = 10-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 8,764 cuft Drainage Area = 0.42 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 = 2.631 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 (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-D Hyd. No. 37 Hydrograph Type = Junction Peak Flow = 6.465 cfs Storm Frequency = 10-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 21,092 cuft Inflow Hydrographs = 35, 36 Total Contrib. Area = 1.22 ac Qp = 6.465 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) PR-2A-D Open Space D PR-2A-D Impervious PR-2A-D

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-D Open Space D Hyd. No. 35 Hydrograph Type = NRCS Runoff Peak Flow = 5.384 cfs Storm Frequency = 25-yr Time to Peak = 12.12 hrs Time Interval = 1 min Runoff Volume = 17,211 cuft Drainage Area = 0.8 ac Curve Number = 80.00 Tc Method = User Time of Conc. (Tc) = 6.0 min Total Rainfall = 8.13 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 5.384 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)

Hydrograph Report File: Eagle Rock Proposed (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-D Impervious Hyd. No. 36 Hydrograph Type = NRCS Runoff Peak Flow = 3.362 cfs Storm Frequency = 25-yr Time to Peak = 12.10 hrs Time Interval = 1 min Runoff Volume = 11,277 cuft Drainage Area = 0.42 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 2.0 min Total Rainfall = 8.13 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 3.362 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 (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 PR-2A-D Hyd. No. 37 Hydrograph Type = Junction Peak Flow = 8.643 cfs Storm Frequency = 25-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 28,488 cuft Inflow Hydrographs = 35, 36 Total Contrib. Area = 1.22 ac Qp = 8.643 cfs 9 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-D Open Space D PR-2A-D Impervious PR-2A-D