What does aquifer storage and recovery (ASR) primarily involve?

Aquifer storage and recovery (ASR) primarily involves the practice of storing excess surface water in aquifers. This process allows for the efficient management of available water resources, especially in areas where water scarcity is a concern. By injecting surplus water, typically during periods of high rainfall or when water demand is low, into underground aquifers, this method helps to recharge the aquifers. Later, when water is needed, the stored water can be recovered and utilized for various purposes, including drinking water supply and irrigation.

This practice not only enhances groundwater supplies but also helps to mitigate issues related to surface water runoff and flood control by capturing and storing water that would otherwise be lost. It represents an innovative approach to managing water resources sustainably and efficiently. In contrast, the other options involve practices that either disrupt groundwater systems or do not focus on the sustainable management of water resources.