Pipe Friction & Total Dynamic Head Calculator
Estimate the total dynamic head (TDH) a pump must overcome. TDH combines vertical lift with friction loss through straight pipe and an allowance for fittings. Use the result with the pump manufacturer’s performance curve to estimate actual flow.
How this estimate works
Friction loss is calculated with the Hazen-Williams method for water moving through smooth pipe, using a C-factor of 140. Add fittings as their equivalent straight-pipe length for a more useful planning estimate.
Friction loss is calculated with the Hazen-Williams method for water moving through smooth pipe, using a C-factor of 140. Add fittings as their equivalent straight-pipe length for a more useful planning estimate.
Before choosing a pump
- Check the selected pump’s performance curve at the calculated TDH, rather than its maximum flow at zero head.
- Measure static head from the pond or basin water surface to the highest discharge point.
- Include every straight run and use the fitting allowance for elbows, valves, check valves, and other restrictions.
- Final plumbing layout, actual inside diameter, and equipment restrictions can change operating conditions.