Managed aquifer recharge (MAR) is a method used to refill depleted groundwater aquifers by intentionally increasing the amount of water that infiltrates into the underground reservoir. This is typically done by capturing excess surface water during times of high flow (such as during heavy rainfall or snowmelt) and routing it to infiltration basins, recharge wells, or spreading ponds where the water can percolate down into the aquifer. MAR is an important tool for improving water supply security, enhancing groundwater levels, and preventing saltwater intrusion in coastal aquifers. It can also help maintain streamflow and ecosystem health in surface water bodies that are connected to depleted aquifers. MAR projects require careful monitoring and management to ensure that injected water is of good quality and does not negatively impact the existing groundwater resources. Some common challenges associated with MAR include water quality issues, aquifer clogging, and legal and regulatory hurdles. Overall, managed aquifer recharge is a valuable strategy for sustainable groundwater management and increasing water resiliency in the face of climate change and growing water demands.