Enter the cycle time and the pumping rate into the calculator to determine the active wet well volume.

Active Wet Well Volume Formula

The following equation is used to calculate the Active Wet Well Volume.

V = CT * Q / 4

  • Where V is the well volume (gallons)
  • CT is the cycle time (min)
  • Q is the pump rate (gallons/min)

To calculate the volume of an active well, multiply the cycle time by the pump rate, then divide by 4.

What is an Active Wet Well Volume?


An active wet well is a well that is filled through active pumping of water into the well. The volume is the average volume of the water held in that well.

How to Calculate Active Wet Well Volume?

Example Problem:

The following example outlines the steps and information needed to calculate Active Wet Well Volume.

First, determine the cycle time of the well. In this example, the cycle time is measured to be 5 min.

Next, determine the pump flow rate. For this well, the flow rate is measured to be 20 gallons per minute.

Finally, calculate the active well volume using the formula above:

V = CT * Q / 4

V = 5 * 20 / 4

V = 25 gallons