How to Calculate Drawdown at a Distance From a Pumped Well
- 1). Get the numbers for the well’s static level and pumped level. If you have a standard model, this will likely be in your well specs (perhaps even on the pump itself). If your well was custom designed, you could call the manufacturer, which should have all this information.
- 2). Convert both of these measurements to inches. Drawdown is measured in inches, while levels generally come in larger units (feet or even yards).
- 3). Subtract the pumped level from the static level. The result is the drawdown, in inches.
Source...