The Tomorrow’s Water model helps communities explore ways to provide future water by reducing the impacts from aquifer overuse and increasing groundwater recharge through playas. It is an adaptive, collaborative process for creating an actionable plan to stabilize community water supplies — with a focus on incorporating playa conservation as part of broader water quantity and quality efforts. Learn more >>

Healthy playas are a primary source of groundwater recharge — and provide important, year-round habitat for birds and other wildlife. Unlike many other wetlands, playas have an irregular wet-dry cycle, which is key to how they function. This video shows how playas recharge the Ogallala aquifer and provide critical wildlife habitat as they go through the cycle.

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When I was a kid in the ’60s, helping my dad on his farm south of Dodge City, he’d talk about the aquifer our old windmills were pumping water from out in the pasture. He always described the Ogallala as an underground river. That understanding of the aquifer implied that groundwater was free to flow, just like a surface river.

In the 50 years since then, scientists have learned lots about underground structures that are permeable to water flow. In some aquifers water is able to freely migrate from one area to another, but not so much when we talk about the Ogallala.

Ken Rainwater is a water resources engineer at Texas Tech. Ken studies groundwater.

“Regionally, here in the Southern High Plains of Texas, we talk about the velocity that the groundwater might move through the aquifer on its own on the order of a few feet per day, maybe a few hundred feet per year, depending on where you are.”

So the groundwater of the Ogallala aquifer really doesn’t flow laterally with much speed.

Randy Stotler’s a hydrogeologist at University of Kansas. He studies western Kansas playas.

“Some of the work that I’ve been doing with the Kansas Geological Survey, we’ve come to realize that there are quite a few parts of the High Plains Aquifer that are actually more compartments, or kind of individual bathtubs, rather than one big river.”

Stotler describes the makeup of the aquifer as not so much a river, but more a series of adjacent ‘bathtubs’ which tend to compartmentalize the effects irrigation wells have on their neighbors. Stotler says the compartmentalization of water becomes more significant as water levels decline.

“Where as one single irrigation well may have connected into a whole bunch of different bathtubs that might be of different sizes, they might reach over to a neighbor’s property. In fact, what we are starting to see is these compartments are becoming more individualized.”

One of Randy’s sites in southwest Kansas demonstrates this process.

“There’s one guy that can turn on his irrigation well — and we have an abandoned well about 60 feet away or so — and we see absolutely no response in that well. But, he might turn on a well and somebody two miles away, we can see the response in that well in the water levels.”

Stotler has learned the lower the water table dips, the more localized are the effects of pumping groundwater.

Playa lakes provide areas of focused recharge to the aquifer, with rates in playa basins 10 to 100 times higher than other areas. That highlights the importance of having high-functioning playa lakes — playas that haven’t been pitted, playas that aren’t silted-in, and playas with a perimeter plant buffer.

Healthy playas provide benefits beyond the amount of aquifer recharge. Water reaching the aquifer through playas is cleaner than water that enters through upland soils and other channels. The result is high quality water reaching the aquifer that can be used by you, your children and future generations.

There’s also the satisfaction of providing local and migrating birds and other critters habitat that helps them thrive.

When we started irrigating the High Plains in the 1950s, the Ogallala was understood to be that vast, virtually endless supply of water. When the water table dropped, we thought the groundwater could flow unimpeded from one area to another. That led to a mentality of ‘If I don’t pump it, the fellow down the road will.’

This new information about the Ogallala is likely to change people’s mentality when they understand that the way you treat your piece of the aquifer, under your property, will affect the amount and quality of your groundwater for future generations.

Playa Country, which ended in late 2016, was a weekly show that featured conservation and wildlife experts — as well as farmers, ranchers and land managers — talking about conservation practices that improve wildlife habitat and landowners’ bottom-line. This episode of Playa Country was made possible by Playa Lakes Joint Venture, and a grant from the Wildlife Conservation Society, with support provided by the Doris Duke Charitable Foundation.

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Researchers are constantly providing new information that the playa lakes of the high plains region are more beneficial to the future of our groundwater supply than was previously understood. When we can take steps to increase the amount of recharge to the aquifer, it benefits dryland farmers and ranchers, but also towns and cities that rely on well water.

Randy Stotler’s a hydrogeologist at University of Kansas. He studies the playas of western Kansas.

“Some research that I’ve done, and others in the last 10 years or so, has shown that playas can actually provide faster recharge rates to the aquifer than even under an irrigated center pivot. So, they can be quite significant in terms of the recharge they are providing to the aquifer.”

Researchers say firm data on the actual amount of aquifer recharge playas can provide is extremely variable, as might be expected. It depends on the size of a playa when it’s wet, how often the playa’s holding water, soil type, and depth to the water table.

“We’re actively trying to understand their role and the amount of recharge that we can get into the aquifers, and how much water is actually there and available for use.”

Not only do playa lakes provide the aquifer recharge, researchers are coming around to the idea playas are capable of recharging the groundwater enough to provide a sustainable amount of water for dryland farming and ranching.

“I certainly agree with that conclusion. The amount of water that is being pulled out of the aquifer for irrigation is much greater than we can expect to see recharged through any individual playa or group of playas, but it can certainly sustain a less water intensive operation such as dryland farming or ranching.”

That’s important new information, as communities struggle to deal with declining aquifers and cyclical droughts.

I ran some numbers with Andy Weinberg, a geoscientist with the Texas Water Development Board. He studies the playas of west Texas. He says some of them can collect a foot and a half of water per year, per acre.

“If you have a playa that is 50 to 100 acres, you’re talking 150 acre-feet a year that may be collected in it.”

So, says Weinberg, on average maybe a quarter of that water infiltrates the soil. Maybe that adds up to a dozen acre-feet of water a year.

“For an irrigator, that’s pretty trivial. But if you’re trying to do a household water supply, water your herd of cattle or something like that, that’s plenty of water to make that a sustainable operation.”

Think about the implication, for a dryland producer who’s adopting sustainable practices, and for ranchers.

Healthy playa lakes can provide sufficient recharge to give the farmstead the expectation of groundwater into the foreseeable future. Of course, that assumes a healthy playa — a playa that isn’t farmed through, a playa that hasn’t been impeded by siltation, and a playa with a grass buffer to hold back the silt and filter contaminants in the runoff.

Not only does the healthy playa’s natural hydrologic mechanism recharge the aquifer, the quality of the water also is improved.

Playas reduce nitrate concentrations. Nitrates are a common contaminant in the groundwater of agricultural areas. Nitrates are an important component in fertilizers, and they’re present in animal manure and septic systems.

“Nitrates will break down in the absence of oxygen. One of the things about playas with the heavy clay soil that they have, when that’s all saturated, the oxygen all gets pulled out of the system. As water moves through the cracks in the clay, the nitrate gets reduced back down to nitrogen and it’s lost out of the system. That’s important for having a good water quality; high nitrates are detrimental to human health.”

A healthy playa lake is a primary way groundwater is replenished by surface water. And a playa lake with a perimeter plant buffer traps sediments and improves the quality of water as it moves to the aquifer below.

Playa Country, which ended in late 2016, was a weekly show that featured conservation and wildlife experts — as well as farmers, ranchers and land managers — talking about conservation practices that improve wildlife habitat and landowners’ bottom-line. This episode of Playa Country was made possible by Playa Lakes Joint Venture and a grant from the Wildlife Conservation Society with support provided by the Doris Duke Charitable Foundation.