Managed aquifer recharge (MAR) is the purposeful recharge of water to aquifers for subsequent recovery or for environmental benefit. MAR supports water supply resiliency. MAR is a well-developed groundwater technology increasingly used
for water security around the world and across the United States.
Categories of MAR include:
- Aquifer storage and recovery (ASR) — injection of water into a well for storage in the aquifer and subsequent recovery from the same well
- Aquifer storage, transfer and recovery (ASTR) — injection of water into a well for storage in the aquifer and recovery from a different well, generally to provide additional water treatment
- Recharge pond or basin — a surface facility, often a large pond, used to increase the infiltration of surface water into a groundwater basin; basins require the presence of permeable soils or sediments at or near the land surface and an unconfined aquifer beneath
- Other MAR Terminology – Click here for a more complete list of MAR terms.
NGWA supports increasing MAR safely and cost-effectively, and has developed a multicomponent initiative highlighting MAR as an important groundwater technology and provide useful information to the industry and well owners.
View MAR contact information specific to your state.
Are you interested in contributing to NGWA’s efforts to promote MAR? Participation in the Managed Aquifer Recharge Workgroup is open to NGWA members. If you are a member, email mar@ngwa.org for meeting information. Not yet a member? Join NGWA today so you can take part in this important work.
MAR Work Group Accomplishments:
- MAR Terminology List
- Webinar - Virus Inactivation
- Webinar - Bureau of Reclamation MAR policy and projects
- MAR inclusion in US Army Corps of Engineers responsibilities
- 2023 MAR Conference - Unleashing Resiliency, Protecting Groundwater Quality
- Update NGWA Position Papers to include MAR benefits
- Groundwater Protection
- Groundwater Protection and Management Critical to the Global Climate Change Discussion
- Best Suggested Practice for Aquifer Storage and Recovery (updated)
- Special Issue of Groundwater (journal) focusing on Managed Aquifer Recharge
- Virus Attenuation in Managed Aquifer Recharge position paper
MAR Work Group Ongoing Projects:
- Best Suggested Practice for Surface Infiltration
- List of State MAR Aquifer Recharge Potential Mapping Factors
Virus Attenuation in Managed Aquifer Recharge position paper
NGWA recently published a new position paper on virus attenuation in managed aquifer recharge.
The paper, created by a work group of NGWA members, is free to download and share with appropriate and interested officials.
The Association supports giving high priority to incorporating thew best available science on subsurface virus attenuation into more practical requirements and cost-effective MAR regulatory frameworks.
Evidence that subsurface virus attenuation during recharge effectively protects groundwater from virus levels typically found in surface water sources includes:
- Scientific studies demonstrating virus-log removal rates
- The success of the EPA Surface Water Treatment Rule requiring 4-log virus removal/inactivation
- The long-term performance of riverbank filtration systems
Alternative aquifer recharge risk-based regulatory approaches in Europe and Australia have successfully used aquifer "attenuation zones" for decades that can be supported by confirmatory monitoring for viruses and other constituents of concern.