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

Hydrograph Report File: Eagle Rock Existing (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 EX-2-U Impervious Hyd. No. 41 Hydrograph Type = NRCS Runoff Peak Flow = 11.99 cfs Storm Frequency = 100-yr Time to Peak = 12.12 hrs Time Interval = 1 min Runoff Volume = 44,646 cuft Drainage Area = 1.05 ac Curve Number = 98.00 Tc Method = User Time of Conc. (Tc) = 5.0 min Total Rainfall = 11.60 in Design Storm = NOAA-D Storm Duration = 24 hrs Shape Factor = 484 Qp = 11.99 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)

Hydrograph Report File: Eagle Rock Existing (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 EX-2-U Hyd. No. 42 Hydrograph Type = Junction Peak Flow = 22.11 cfs Storm Frequency = 100-yr Time to Peak = 12.13 hrs Time Interval = 1 min Hydrograph Volume = 99,326 cuft Inflow Hydrographs = 38, 39, 40, 41 Total Contrib. Area = 2.94 ac Qp = 22.11 cfs 25 24 23 22 21 20 19 18 17 16 15 14 13 Q (cfs) 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) EX-2-U Open Space C EX-2-U Woods C EX-2-U Gravel C EX-2-U Impervious EX-2-U

TOTAL EXISTING FLOW TO POA-2

Hydrograph Report File: Eagle Rock Existing (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 TOTAL POA-2 Hyd. No. 44 Hydrograph Type = Junction Peak Flow = 11.97 cfs Storm Frequency = 2-yr Time to Peak = 12.12 hrs Time Interval = 1 min Hydrograph Volume = 49,371 cuft Inflow Hydrographs Total Contrib. Area = 0.0 ac Qp = 11.97 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-2-D EX-2-U TOTAL POA-2

Hydrograph Report File: Eagle Rock Existing (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 TOTAL POA-2 Hyd. No. 44 Hydrograph Type = Junction Peak Flow = 21.02 cfs Storm Frequency = 10-yr Time to Peak = 12.12 hrs Time Interval = 1 min Hydrograph Volume = 88,816 cuft Inflow Hydrographs Total Contrib. Area = 0.0 ac Qp = 21.02 cfs 24 23 22 21 20 19 18 17 16 15 14 13 Q (cfs) 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) EX-2-D EX-2-U TOTAL POA-2

Hydrograph Report File: Eagle Rock Existing (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 TOTAL POA-2 Hyd. No. 44 Hydrograph Type = Junction Peak Flow = 42.47 cfs Storm Frequency = 100-yr Time to Peak = 12.12 hrs Time Interval = 1 min Hydrograph Volume = 185,037 cuft Inflow Hydrographs Total Contrib. Area = 0.0 ac Qp = 42.47 cfs 48 46 44 42 40 38 36 34 32 30 28 26 Q (cfs) 24 22 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-2-D EX-2-U TOTAL POA-2

TOTAL ALLOWABLE FLOW TO POA-2

Hydrograph Report File: Eagle Rock Existing (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 POA-2 2YR ALLOW Hyd. No. 45 Hydrograph Type = Junction Peak Flow = 8.995 cfs Storm Frequency = 2-yr Time to Peak = 12.12 hrs Time Interval = 1 min Hydrograph Volume = 37,589 cuft Inflow Hydrographs Total Contrib. Area = 0.0 ac Qp = 8.995 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) EX-2-D 2 YR ALLOW EX-2-U POA-2 2YR ALLOW

Hydrograph Report File: Eagle Rock Existing (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 POA-2 10YR ALLOW Hyd. No. 46 Hydrograph Type = Junction Peak Flow = 18.44 cfs Storm Frequency = 10-yr Time to Peak = 12.12 hrs Time Interval = 1 min Hydrograph Volume = 78,361 cuft Inflow Hydrographs Total Contrib. Area = 0.0 ac Qp = 18.44 cfs 21 20 19 18 17 16 15 14 13 12 11 Q (cfs) 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-2-D 10 YR ALLOW EX-2-U POA-2 10YR ALLOW

Hydrograph Report File: Eagle Rock Existing (Future).hys Hydrology Studio v 3.0.0.39 10-21-2025 POA-2 100YR ALLOW Hyd. No. 47 Hydrograph Type = Junction Peak Flow = 38.36 cfs Storm Frequency = 100-yr Time to Peak = 12.12 hrs Time Interval = 1 min Hydrograph Volume = 167,894 cuft Inflow Hydrographs Total Contrib. Area = 0.0 ac Qp = 38.36 cfs 44 42 40 38 36 34 32 30 28 26 24 Q (cfs) 22 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-2-D 100 YR ALLOW EX-2-U POA-2 100YR ALLOW