The following procedures can be used to measure the static or non-pumping water level in a well:
- Ensure that the pump is shut off until the measurement is completed.
- If the pump has been running, wait at least 15 to 30 minutes to allow the water level to recover before taking a measurement. It should be noted that in a low permeable aquifer the recovery time may take several hours.
- After taking an initial measurement, wait another 15 to 30 minutes and measure again to ensure that the water level is stable and is actually the static water level. The best time to measure the static (non-pumping) water level is the when the pump has been resting for quite some time, for instance early in the morning prior to any water use.
The pumping water level is recorded while the well is operating. For comparison purposes, the pumping water level measurements should be taken for pumping periods of the same duration. For example, the pumping water level and the discharge rate can be measured after the pump has been operating for 30 minutes. Any future measurements should then be taken after 30 minutes pumping. If the discharge rates are the same but the pumping water level has decreased, than plugging of the well intake may have occurred.