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 POA-2 Hyd. No. 70 Hydrograph Type = Junction Peak Flow = 15.04 cfs Storm Frequency = 25-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 94,525 cuft Inflow Hydrographs Total Contrib. Area = 0.0 ac Qp = 15.04 cfs 17 16 15 14 13 12 11 10 9 Q (cfs) 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 26 27 28 29 30 Time (hrs) PR-2A Routing PR-2B Routing PR-2C-D PR-2C-U POA-2

Hydrograph Report File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 POA-2 Hyd. No. 70 Hydrograph Type = Junction Peak Flow = 23.96 cfs Storm Frequency = 100-yr Time to Peak = 12.10 hrs Time Interval = 1 min Hydrograph Volume = 141,291 cuft Inflow Hydrographs Total Contrib. Area = 0.0 ac Qp = 23.96 cfs 27 26 25 24 23 22 21 20 19 18 17 16 15 14 Q (cfs) 13 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 26 27 28 29 Time (hrs) PR-2A Routing PR-2B Routing PR-2C-D PR-2C-U POA-2

SUMMARY OF PROPOSED PEAK DISCHARGES

Hydrograph 2-yr Summary File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 Hyd. Hydrograph Hydrograph Peak Time to Hydrograph Inflow Maximum Maximum Flow Peak Volume Hyd(s) Elevation Storage No. Type Name (cfs) (hrs) (cuft) (ft) (cuft) 1 NRCS Runoff PR-1A-D Grass D 0.575 12.13 1,874 ---- 2 NRCS Runoff PR-1A-D Imp 1.082 12.10 3,514 ---- 3 Junction PR-1A-D 1.622 12.10 5,388 1, 2 5 NRCS Runoff PR-1A-U Open Space C 0.389 12.17 1,478 ---- 6 NRCS Runoff PR-1A-U Woods C 0.074 12.18 291 ---- 7 NRCS Runoff PR-1A-U Imp 1.690 12.10 5,490 ---- 8 Junction PR-1A-U 2.062 12.10 7,259 5, 6, 7 10 Junction PR-1A Total 3.684 12.10 12,647 3, 8 11 Pond Route PR-1A Routing 1.034 12.33 9,748 10 535.18 5,747 13 NRCS Runoff PR-1B-D 0.680 12.12 2,102 ---- 15 NRCS Runoff PR-1B-U Open Space C 0.305 12.20 1,276 ---- 16 NRCS Runoff PR-1B-U Woods C 0.510 12.22 2,213 ---- 17 NRCS Runoff PR-1B-U Impervious 3.580 12.12 13,475 ---- 18 Junction PR-1B-U 4.256 12.13 16,965 15, 16, 17 21 Junction PR-1B (Swale) 4.925 12.13 19,068 13, 18 24 NRCS Runoff PR-1C-D Open Space D 0.645 12.10 1,748 ---- 25 NRCS Runoff PR-1C-D Impervious 0.372 12.10 1,208 ---- 26 Junction PR-1C-D

D Open Space D 0.645 12.10 1,748 ---- 25 NRCS Runoff PR-1C-D Impervious 0.372 12.10 1,208 ---- 26 Junction PR-1C-D 1.017 12.10 2,955 24, 25 28 NRCS Runoff PR-1C-U Open Space C 0.902 12.15 3,213 ---- 29 NRCS Runoff PR-1C-U Impervious 3.954 12.10 13,118 ---- 30 Junction PR-1C-U 4.735 12.10 16,331 28, 29 32 Junction POA-1 11.32 12.12 48,102 11, 21, 26, 30 35 NRCS Runoff PR-2A-D Open Space D 1.555 12.12 4,806 ---- 36 NRCS Runoff PR-2A-D Impervious 1.420 12.10 4,612 ----

Hydrograph 2-yr Summary File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 Hyd. Hydrograph Hydrograph Peak Time to Hydrograph Inflow Maximum Maximum Flow Peak Volume Hyd(s) Elevation Storage No. Type Name (cfs) (hrs) (cuft) (ft) (cuft) 37 Junction PR-2A-D 2.928 12.10 9,417 35, 36 39 NRCS Runoff PR-2A-U Open Space C 0.173 12.25 783 ---- 40 NRCS Runoff PR-2A-U Woods C 0.135 12.25 635 ---- 41 NRCS Runoff PR-2A-U Impervious 2.299 12.10 7,467 ---- 42 Junction PR-2A-U 2.492 12.10 8,885 39, 40, 41 45 Junction PR-2A 5.420 12.10 18,303 37, 42 46 Pond Route PR-2A Routing 0.856 12.62 14,915 45 538.07 9,171 48 NRCS Runoff PR-2B-D Open Space D 0.061 12.10 175 ---- 49 NRCS Runoff PR-2B-D Impervious 1.251 12.10 4,063 ---- 50 Junction PR-2B-D 1.312 12.10 4,238 48, 49 52 NRCS Runoff PR-2B-U Open Space C 0.015 12.10 41.3 ---- 53 NRCS Runoff PR-2B-U Impervious 0.101 12.10 329 ---- 54 Junction PR-2B-U 0.117 12.10 371 52, 53 56 Junction PR-2B 1.429 12.10 4,608 50, 54 57 Pond Route PR-2B Routing 0.184 12.62 4,595 56 553.73 1,923 59 NRCS Runoff PR-2C-D Open Space D 1.169 12.10 3,167 ---- 60 NRCS Runoff PR-2C-D Impervious 0.980 12.10 3,184 ---- 61

59 NRCS Runoff PR-2C-D Open Space D 1.169 12.10 3,167 ---- 60 NRCS Runoff PR-2C-D Impervious 0.980 12.10 3,184 ---- 61 Junction PR-2C-D 2.150 12.10 6,352 59, 60 63 NRCS Runoff PR-2C-U Open Space C 0.690 12.23 3,030 ---- 64 NRCS Runoff PR-2C-U Woods C 0.609 12.23 2,783 ---- 65 NRCS Runoff PR-2C-U Gravel C 0.223 12.10 632 ---- 66 NRCS Runoff PR-2C-U Impervious 1.623 12.10 5,271 ---- 67 Junction PR-2C-U 2.706 12.10 11,716 63, 64, 65, 66 70 Junction POA-2 5.668 12.10 37,577 46, 57, 61, 67

Hydrograph 10-yr Summary File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 Hyd. Hydrograph Hydrograph Peak Time to Hydrograph Inflow Maximum Maximum Flow Peak Volume Hyd(s) Elevation Storage No. Type Name (cfs) (hrs) (cuft) (ft) (cuft) 1 NRCS Runoff PR-1A-D Grass D 1.147 12.13 3,769 ---- 2 NRCS Runoff PR-1A-D Imp 1.691 12.10 5,600 ---- 3 Junction PR-1A-D 2.783 12.10 9,369 1, 2 5 NRCS Runoff PR-1A-U Open Space C 0.881 12.17 3,257 ---- 6 NRCS Runoff PR-1A-U Woods C 0.185 12.17 686 ---- 7 NRCS Runoff PR-1A-U Imp 2.643 12.10 8,750 ---- 8 Junction PR-1A-U 3.532 12.10 12,694 5, 6, 7 10 Junction PR-1A Total 6.316 12.10 22,063 3, 8 11 Pond Route PR-1A Routing 2.246 12.28 19,163 10 535.71 8,419 13 NRCS Runoff PR-1B-D 1.356 12.12 4,228 ---- 15 NRCS Runoff PR-1B-U Open Space C 0.694 12.20 2,812 ---- 16 NRCS Runoff PR-1B-U Woods C 1.281 12.20 5,227 ---- 17 NRCS Runoff PR-1B-U Impervious 5.603 12.12 21,477 ---- 18 Junction PR-1B-U 7.312 12.13 29,515 15, 16, 17 21 Junction PR-1B (Swale) 8.638 12.13 33,743 13, 18 24 NRCS Runoff PR-1C-D Open Space D 1.268 12.10 3,514 ---- 25 NRCS Runoff PR-1C-D Impervious 0.581 12.10 1,925 ---- 26 Junction PR-1C-D

D Open Space D 1.268 12.10 3,514 ---- 25 NRCS Runoff PR-1C-D Impervious 0.581 12.10 1,925 ---- 26 Junction PR-1C-D 1.849 12.10 5,439 24, 25 28 NRCS Runoff PR-1C-U Open Space C 2.035 12.15 7,078 ---- 29 NRCS Runoff PR-1C-U Impervious 6.186 12.10 20,908 ---- 30 Junction PR-1C-U 7.998 12.10 27,986 28, 29 32 Junction POA-1 19.76 12.12 86,331 11, 21, 26, 30 35 NRCS Runoff PR-2A-D Open Space D 3.098 12.12 9,664 ---- 36 NRCS Runoff PR-2A-D Impervious 2.220 12.10 7,350 ----

Hydrograph 10-yr Summary File: Eagle Rock Proposed (Current).hys Hydrology Studio v 3.0.0.39 10-21-2025 Hyd. Hydrograph Hydrograph Peak Time to Hydrograph Inflow Maximum Maximum Flow Peak Volume Hyd(s) Elevation Storage No. Type Name (cfs) (hrs) (cuft) (ft) (cuft) 37 Junction PR-2A-D 5.246 12.10 17,014 35, 36 39 NRCS Runoff PR-2A-U Open Space C 0.393 12.23 1,725 ---- 40 NRCS Runoff PR-2A-U Woods C 0.339 12.23 1,500 ---- 41 NRCS Runoff PR-2A-U Impervious 3.594 12.10 11,901 ---- 42 Junction PR-2A-U 4.094 12.10 15,126 39, 40, 41 45 Junction PR-2A 9.340 12.10 32,140 37, 42 46 Pond Route PR-2A Routing 2.457 12.37 28,753 45 538.57 14,024 48 NRCS Runoff PR-2B-D Open Space D 0.122 12.10 351 ---- 49 NRCS Runoff PR-2B-D Impervious 1.956 12.10 6,475 ---- 50 Junction PR-2B-D 2.078 12.10 6,827 48, 49 52 NRCS Runoff PR-2B-U Open Space C 0.033 12.10 90.9 ---- 53 NRCS Runoff PR-2B-U Impervious 0.159 12.10 525 ---- 54 Junction PR-2B-U 0.192 12.10 616 52, 53 56 Junction PR-2B 2.270 12.10 7,443 50, 54 57 Pond Route PR-2B Routing 0.246 12.82 7,429 56 554.20 3,173 59 NRCS Runoff PR-2C-D Open Space D 2.298 12.10 6,369 ---- 60 NRCS Runoff PR-2C-D Impervious 1.533 12.10 5,075 ---- 61