Kerby’s Time of Concentration Calculator

Calculate the time of concentration using Kerby’s Equation:
\[ T_c = \frac{0.00045\, L^{0.85}}{\sqrt{S}} \]

* Enter the watercourse length \( L \) (ft) and the slope \( S \) (ft/ft).

Step 1: Enter Parameters

Watercourse Length, \( L \) (ft):

Example: 1000 ft

Slope, \( S \) (ft/ft):

Example: 0.01 ft/ft

Calculated Time of Concentration