Water Flow Rates for Pipe Sizes with Excel Formulas, Using the Hazen Williams Formula

The Excel Formulas in the spreadsheet templates that can be downloaded will calculate water flow rates for pipe sizes (diameters and lengths) using the Hazen Williams formula. Both S.I. versions and U.S. versions of the Hazen Williams equation are presented and discussed. The limitations for use of the Hazen Williams equation for water flow rate calculations are discussed. Water flow rate calculations with the Hazen Williams formula make use of the pipe diameter, pipe length, the head loss or pressure difference driving the flow, and a Hazen Williams coefficient dependent upon the roughness of the pipe material.