# Hazen-Williams Equation Pipe Inside Diameter

This inside pipe diameter formula is used in Hazen-Williams equations and the coefficient formula.

### Hazen-Williams Equation Pipe Inside Diameter formula

\(\large{ d = \left( \frac {Q} { 0.285 \; C \; m^{0.54} } \right) ^{\frac {1}{2.63} } }\)

Where:

\(\large{ d }\) = pipe inside diameter (ID)

\(\large{ Q }\) = flow rate

\(\large{ C }\) = Hazen-Williams Coefficient

\(\large{ m }\) = hydraulic grade line slope

Tags: Equations for Pipe Sizing Equations for Hazen-Williams