What does overdraft refer to in the context of water use?

In the context of water use, overdraft specifically refers to the scenario where groundwater is pumped at a rate that exceeds the natural replenishment of that groundwater supply. This means that the amount of water being extracted from aquifers exceeds the amount of water that can be naturally replenished through precipitation, surface water infiltration, and other natural processes.

When groundwater is overdrawn, it can lead to a variety of negative consequences, such as declining water levels in wells, land subsidence, reduced water quality, and significant ecological impacts. Sustainable groundwater management aims to balance extraction with recharge to prevent such overdraft conditions.

This understanding of overdraft is critical in water resource management, especially in arid regions like Arizona, where groundwater often represents a vital resource for agricultural, industrial, and domestic uses.