As many states expect continued drought in 2016 and beyond, the management of aquifers will be increasingly important, according to the National Ground Water Association (NGWA).
One potential method to help provide for water when it is needed is called managed aquifer recharge (MAR). MAR captures available water during wet periods, periods of low demand, or water that would be lost otherwise. Then it moves this water under controlled conditions into aquifers.
“MAR will become an increasingly important tool for mitigating the economic, environmental and public health impacts of water shortages,” says William Alley, NGWA's director of science and technology. NGWA has published an information brief, as well as a best suggested practices document on the subject.
“Integrating MAR into the nation's water infrastructure will require proper siting selection, design, construction, operation, and maintenance, but it can be done,” Alley said.
MAR projects are used to:
- Provide more stable water supplies during drought
- Mitigate land subsidence where depleted aquifers collapse, resulting in a dropping of the ground’s surface
- Supplement the quantity of groundwater available
- Conserve and dispose of runoff and floodwaters
- Reduce or eliminate declines in the water level of groundwater reservoirs
- Reduce or halt saltwater intrusion
- Improve groundwater quality
- Store water in off-seasons for use during the growing seasons
Allow stored water to be released during dry periods to augment minimum streamflows and maintain lake levels, thereby benefiting ecosystems
Successful MAR projects have been operated by the Orange County (California) Water District; Central Arizona Groundwater Replenishment District; the Peace River Manasota Regional Water Supply Authority (Florida); United Water Resources (Idaho); Rio Rancho, New Mexico; and Dayton, Ohio. There are hundreds of such projects in place across the nation.
One reason the potential of MAR is so great, NGWA says, is because of the magnitude and importance of groundwater to the nation’s water resources. About 78 percent of community water systems and many individual households with an independent source of water use groundwater, according to NGWA.
NGWA is a nonprofit that supports responsible development, management and use of water resources. It’s comprised of groundwater professionals ranging from contractors to equipment manufacturers to scientists and engineers. For more information, visit www.ngwa.org.