1240815StormWaterManagementReport

1=Exfiltration (Exfiltration Controls 0.03 cfs) Primary OutFlow Max=0.23 cfs @ 1.14 hrs HW=412.30' (Free Discharge) 2=Culvert (Passes 0.23 cfs of 0.27 cfs potential flow) 3=Orifice (Orifice Controls 0.23 cfs @ 1.86 fps) 4=Grate ( Controls 0.00 cfs) 57

PLEASANT VALLEY WAY 1240815-pipes Water Quality Storm Water Quality Rainfall=1.25", P2=3.47" Prepared by Casey & Keller, Inc Printed 9/12/2025 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Pond 5: Pipes Hydrograph 0.36 0.33 cfs 0.34 Inflow Outflow 0.32 Discarded 0.3 Inflow Area=0.359 ac Primary 0.28 0.26 cfs 0.26 Peak Elev=412.30' 0.23 cfs 0.24 Storage=146 cf 0.22 Flow (cfs) 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.03 cfs 0.04 0.02 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) 58

PLEASANT VALLEY WAY 1240815-pipes Water Quality Storm Water Quality Rainfall=1.25", P2=3.47" Prepared by Casey & Keller, Inc Printed 9/12/2025 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Summary for Subcatchment 6: Bypass Runoff = 0.00 cfs @ 1.25 hrs, Volume= 0.000 af, Depth= 0.07" Routed to Link 7 : Proposed Runoff by SCS TR-20 method, UH=SCS, Split Pervious/Imperv. UI as Pervious, Time Span= 0.00-72.00 hrs, dt= 0.05 Water Quality Storm Water Quality Rainfall=1.25", P2=3.47" Area (sf) CN Description 605 74 >75% Grass cover, Good, HSG C 605 74 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.9 100 0.0650 0.28 Sheet Flow, 1 Grass: Short n= 0.150 P2= 3.47" 0.1 28 0.0900 4.50 Shallow Concentrated Flow, 2 Grassed Waterway Kv= 15.0 fps 6.0 128 Total Subcatchment 6: Bypass Hydrograph 0.002 0.00 cfs 0.002 Runoff 0.002 0.002 Water Quality Storm 0.002 0.002 Water Quality Rainfall=1.25" 0.002 0.002 P2=3.47" 0.002 0.001 Runoff Area=605 sf

0.002 0.001 Runoff Area=605 sf Runoff Volume=0.000 af Flow (cfs) 0.001 0.001 0.001 Runoff Depth=0.07" 0.001 0.001 Flow Length=128' 0.001 0.001 Tc=6.0 min 0.001 CN=74/0 0.000 0.000 0.000 0.000 0 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) 59

PLEASANT VALLEY WAY 1240815-pipes Water Quality Storm Water Quality Rainfall=1.25", P2=3.47" Prepared by Casey & Keller, Inc Printed 9/12/2025 HydroCAD® 10.20-7a s/n 03272 © 2025 HydroCAD Software Solutions LLC Summary for Link 7: Proposed Inflow Area = 0.373 ac, 69.07% Impervious, Inflow Depth = 0.16" for Water Quality event Inflow = 0.23 cfs @ 1.14 hrs, Volume= 0.005 af Primary = 0.23 cfs @ 1.14 hrs, Volume= 0.005 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.05 hrs Link 7: Proposed Hydrograph 0.26 0.25 0.23 cfs 0.24 Inflow Primary 0.23 0.22 0.21 Inflow Area=0.373 ac 0.2 0.19 0.18 0.17 0.16 0.15 Flow (cfs) 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 Time (hours) 60

DRAINAGE AREA MAPS 61

Chain-Link Fence 41 Chain-Link Fence 18 2.87' over E 3 41 2 3.04' over E 412 413 416 413 415 41 414 4 28 LF SHALLOW 13 LF CONCENTRATIED FLOW 4

13 LF CONCENTRATIED FLOW 4 SHEET FLOW 414 41 13 LF SHALLOW CONCENTRATIED FLOW 41 5 Vinyl Fence 0.25' over S 5 415 41 DA EXISTING 415 21 LF 417 416 SHEET FLOW 16242 SF 6

6 0.373 AC 41 N 62°02'20" W 130.00' S 61°58'0" E 130.00' Cn=90 417 416 Curb 416 1.0' 17 FF=417.00 Over N 4 FF=417.28 FF=416.93

FF=416.93 FF=424.50 418 FF=417.16 AC 417 417 FF=424.65 418 Curb 418 1.06' over S AC 41 66 LF 1-Story 8 2-Story 418 SHEET FLOW Frame Mixed-Use Dwelling AC 41 41