EngineeringToolkit

Hazen-Williams Equation Formula

Calculates the water flow velocity in a pipe based on slope and roughness.

Formula

v = 0.85 · C · R^0.63 · S^0.54

Discipline: Civil Engineering. Result unit: m/s.

Variables and units

  • v — Velocity (m/s): Flow velocity
  • C — Hazen-Williams Coefficient: Pipe roughness coefficient
  • R — Hydraulic Radius (m): Hydraulic radius
  • S — Slope (m/m): Slope of the energy grade line