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Recharge rejected Hopes to replenish aquifer dashed WHITE DEER — The hope was that the giant Ogallala Aquifer that underlies much of the Great Plains, and specifically the Panhandle Groundwater Conservation District, could be recharged. But the latest study appears to have dashed that hope. The water conservation district funded a preliminary study in 2006 that indicated some recharge of the aquifer beneath the rolling rangeland of Roberts and Hemphill counties. That led to a second study conducted by the Bureau of Economic Geology at the University of Texas. Dr. Bridget Scanlon of the Bureau of Economic Geology, who headed the study and who is among the premier recharge experts in the state, said she had never seen recharge on a rangeland area before, so she was very interested. "Usually," said Amy Crowell, hydrologist with the water district, "the indigenous grasses and shrubs use the water there. That's why they're acclimated for this climate. They use what water is there." Scanlon was excited to see recharge on rangeland. "We thought, 'Good, what better place than Roberts County,'" Crowell said. Roberts County has been at the center of a water war for the past decade with the Canadian River Municipal Water Authority buying up almost 300,000 acres of water rights to feed its 11 member cities in the Texas Panhandle and South Plains and the city of Amarillo buying water rights for future use. In addition, Boone Pickens and his Mesa Water corporation is buying water rights to sell water to thirsty urban areas downstate. Crowell said the district was happy to think there was some recharge where there is now concentrated pumping by CRMWA and planned pumping for other projects. "It would be good news for the long-term water supply up there," Crowell said. She said they were really excited going in, but the numbers did not turn out as hoped for. She said that closer to the Canadian River, which bisects the county, there is loose, unconsolidated sand. "That's really the only place we saw recharge on rangeland," Crowell said. On the plains, there has been evidence that as playas filled up, there is some recharge around the edges as the water overflowed the bowl of the clay lining covering the bottom of the lakes. "That's how it works in the playas out here on the plains," Crowell said. Roberts County is more rolling and has sand hills. "Our hope was that was going to really help," she said. Crowell said they did see some recharge on farmed land. "You're more likely to see recharge in plowed land," she said, "because there's no vegetation using the water unless there's a crop planted." With farmland in this area, she said that many times there's also some supplementary irrigation going on. "We did see that where we expected to see it," Crowell said, "but the stuff we were really hoping for on the rangeland just wasn't there. It turns out that it was a very local phenomenon." Crowell said that the first thing most people suggest is drilling holes in the tens of thousands of playa lakes that dot the Great Plains and allow, or pump, the water into the aquifer. "It doesn't work," Crowell said. The problem is that the holes or recharge wells soon silt up. A secondary problem is that the playa lakes are all too often filled with run off from surrounding cropland. Crowell asked whether it is a good idea to pump that run-off, with its pesticides and herbicides, directly into the pristine waters of the aquifer. "It was a great study," Crowell said of the latest study, "but we were disappointed in the numbers." E-mail
comments about this story Posted: April 3, 2008
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