Managed aquifer recharge, or MAR, refers to the intentional recharge of water to aquifers for subsequent use or environmental benefit.
MAR offers numerous benefits, including:
- storage to improve security of water supply
- natural treatment
- a low-cost, low-energy water supply option
- replenishing over-exploited aquifers
- no evaporation loss, algae and mosquitoes.
A variety of methods can be used to recharge aquifers and the choice of method is influenced by the local hydrogeology. For example, open infiltration ponds can be used to recharge unconfined aquifers, while injection well techniques such as aquifer storage and recovery (ASR) may be required to recharge deeper confined aquifers.
MAR provides storage and treatment for all available water resources, such as natural water sources (surface water, groundwater), recycled water (urban stormwater, industrial or urban wastewater) or desalinated seawater.
MAR plays an important role in integrating the management of surface and groundwater resources for security of water supply while ensuring public health and environmental protection. Water storage is essential to improve the sustainability and resilience of water supply, both of which contribute to urban amenity and liveability of cities. In addition, natural treatment in the aquifer offers a low-cost, low-energy water treatment option.