Wastewater math

Wastewater Math Formulas

The formulas used most in entry and intermediate wastewater operator math, each with a worked example you can follow step by step.

Detention Time Formula
How long wastewater stays in a tank, from the tank volume and the flow.
Pounds Loading Formula
Pounds per day from flow in MGD, concentration in mg/L and 8.34 lb/gal.
Chemical Feed Rate Formula
Pounds per day of chemical to feed, including the product's purity.
Percent Removal Formula
How much of a pollutant a process removes, from influent and effluent.
Channel Flow Rate Formula
Flow, area and velocity in an open channel.
Tank Area Formulas
The area of rectangular and circular tanks.
MGD to GPD Conversion
Converting million gallons per day to gallons per day.