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 small 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 and clean water for residents including drilling more and deeper wells — just to provide the same amount of water.
A healthy, functioning system of playas can provide high-quality water to help support the needs of a small town.
Communities can proactively address a declining municipal water supply by assisting with irrigation water conservation, better surface water management, and playa restoration and protection. Once water use has been reduced, healthy playas can provide a sustainable source of future water.
Groundwater recharge is a continuous process; the water recharging through playas today will be available for use by the next and future generations with long-term playa and water conservation. A healthy, functioning system of playas can provide high-quality water to help support the needs of a small town.
Average Recharge Rate
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.
Incorporating Playas Into a Water PlanPlaya restoration includes filling pits, ditches, and diversions, installing native vegetation buffers, and managing surface water runoff to flow into playas. Low-tech, low-cost solutions for increasing the amount of water flowing through playas — while limiting sediments and impurities — are available. By diverting stormwater into playas, towns can keep roads and property from flooding while increasing the amount of groundwater recharge.
It is also important to reduce or eliminate competing water use. Although playas are a primary source of recharge, withdrawals from irrigation greatly exceed recharge from playas. However, some towns have found that when nearby well use is reduced or turned off, water levels in the aquifer rebound. Around the region, people are talking about and experimenting with how to lessen the amount of water used for irrigation and may be interested in programs which offer technical and financial support to retire irrigation wells near towns and municipal wells.
WE CAN HELP
The PLJV partnership can work with your community to develop a restoration plan for the playas that feed the aquifer underneath town wells. The plan will identify opportunities, such as grant programs, to protect healthy playas and conduct restoration work for those that have been modified. Having healthy playas to the northwest of the town’s water supply provides the most benefit since water in the aquifer generally flows in a southeasterly direction.