HomeMy WebLinkAboutCHERRY STREET COTTAGES - PDP - PDP160041 - SUBMITTAL DOCUMENTS - ROUND 2 - STORMWATER-RELATED DOCUMENTS17-06-02_2-yr peak runoff_UD-Rational_Revised.xls, Notation 6/6/17, 8:33 AM
List of Variables
A = watershed area in acres
C = runoff coefficient
C1, C2, and C3 = coefficients in IDF formula
C5 = 5-yr runoff coefficient
I = rainfall intensity in inches/hour
ID = user defined identification number
L = flow length in ft
S = slope for flow length in ft/ft
P1 = one hour precipitation value in inches
Tc = time of concentration in minutes
Td = design rainfall duration in minutes
Tf = flow time in minutes
Tr = return period in years
Qp = peak runoff rate in cfs
V = flow velocity in ft/second