Because playas are a primary source of groundwater recharge, they can be an important part of a sustainable approach to securing water for communities in the western Great Plains. Aquifer levels are decreasing throughout the region, with many towns and communities that depend on the Ogallala aquifer at risk for continuing groundwater loss. These towns are facing a future water supply that may be limited and searching for solutions to continue providing abundant, clean water for residents.
Communities can proactively address a declining municipal water supply by reducing the impacts from aquifer overuse and increasing groundwater recharge through playas. Once water use has been reduced, healthy playas can provide a sustainable source of future water.
Connecting People, Playas and the Ogallala Aquifer
Playas across the region recharge at an average annual rate of about three inches per year* — that’s three inches of water the size of the playa moving toward the aquifer each year there is adequate rainfall. For example, a four-acre playa, which is a very small one, sends approximately an acre-foot of water toward the aquifer. That’s 325,851 gallons of water, more than enough to supply a couple of families for a year.
The benefit goes beyond simple recharge; playas clean the water as it travels toward the aquifer. Studies show that water reaching the aquifer through playas is of higher quality than that going through other pathways. This happens in two ways: first, as rainfall and runoff travel toward the playa, the surrounding grasses trap sediments, which can carry contaminants into the playa; then, as the water moves through the clay floor of the playa, a second ‘cleaning’ process occurs as the soils beneath the playa remove nitrates and other dissolved contaminants. To see how this happens, watch our How Playas Work video.
*Gurdak and Roe, 2009. This report provides a review of all the playa studies with calculated recharge rates up to 2009. Three inches is an approximate average.