Southtowns Record

PBA05.14.2026packet

Government
Town of West Seneca
Board
Planning Board
Meeting
May 14, 2026, 6:00 p.m.
Posted by publisher
May 12, 2026
Kind
Agenda packet
Topics
Water, sewer and drainage, Zoning and land use, Housing, Roads and traffic, Budget and taxes, Parks and recreation, Public safety

Original document

Same meeting

Text · page 224 of 359

Read the whole document on one page (all 359 pages, each with its own heading)

E_App E_Post-Development Model  NY-West Seneca 24-hr S1 10-yr Rainfall=3.14"
Prepared by Labella Associates  Printed 4/20/2026
HydroCAD® 10.20-7a s/n 09581 © 2025 HydroCAD Software Solutions LLC  Page 27

  Summary for Subcatchment PS-3:

Runoff  =  1.75 cfs @ 12.04 hrs, Volume=  0.096 af, Depth= 1.78"
  Routed to Pond BIO-2 : Filtration Bioretention

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs
NY-West Seneca 24-hr S1 10-yr Rainfall=3.14"

  Area (sf)  CN  Description
  9,466  98  Paved parking, HSG D
  18,801  80  >75% Grass cover, Good, HSG D
  28,267  86  Weighted Average
  18,801  66.51% Pervious Area
  9,466  33.49% Impervious Area

  Tc Length  Slope Velocity Capacity Description
  (min) (feet)  (ft/ft) (ft/sec) (cfs)
  6.0  Direct Entry, Direct

  Subcatchment PS-3:
  Hydrograph

  Runoff
  1.75 cfs
  NY-West Seneca 24-hr S1 10-yr
  Rainfall=3.14"
  Runoff Area=28,267 sf
  Runoff Volume=0.096 af
  Runoff Depth=1.78"
  Flow (cfs)

  Tc=6.0 min
  1
  CN=86

  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)

  Page 224 of 359