Water & Environmental

Stormwater & Hydrology Calculators & Design Tools

Rational Method peak runoff Q=CIA, Manning open channel hydraulics & basin volume.

ASCE Manual of Practice No. 77 / AASHTO Drainage Manual

Rational Method Peak Stormwater Runoff (Q = C·I·A)

Peak discharge calculation for small urban and rural watersheds

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FHWA HEC-22 / Chow Open-Channel Hydraulics

Manning’s Open Channel Flow & Velocity

Flow capacity, depth, and velocity for trapezoidal, rectangular, and pipe channels

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