Trench Drain Sizing Calculator

Size trench drains for linear drainage applications using Manning equation.

Total length of trench drain.
feet
Width of trench channel.
inches
Longitudinal slope.
%
Total area draining to trench.
sq ft

Results

Trench Capacity-GPM
Flow Velocity-ft/s
Outlet Pipe Size-inches
References: Based on Manning equation for open channel flow and trench drain design