What does 'static water level' in a well refer to?

The term 'static water level' in a well specifically denotes the height of the water surface when no water is being extracted or pumped from the well. This level is critical in understanding the well's water availability and its recharge characteristics. When a well is not being pumped, it allows for the measurement of the natural water level, which can provide insights into the aquifer's health and the effects of rainfall and drought conditions.

In comparison, the other options describe different states of water level not related to the static condition. The water level during heavy rain may rise temporarily, but it does not reflect the true static level, as it is influenced by external factors. The maximum depth of the well simply indicates how deep the well goes, rather than the water level. Additionally, the current water level while pumping reflects a dynamic situation where the water is actively being removed, thus not aligning with the definition of a static condition.