Desalination to Ease Strain on Aquifer
The Barton Springs Edwards Aquifer Conservation District is going after federal grant money to build an experimental desalination plant in Central Texas. The plant will use new techniques to draw the brackish water from the portion of the aquifer located east of I-35 that had previously been unusable. According to the State Water Plan, the population of the state will double by 2060.
“With that population increase there’s obviously going to be an increase in demand, there’s going to be water needed to accommodate that demand. It’s going to be a thirsty population,” said John Dupnik, a geoscientist with the conservation district. “Ultimately, were trying to reduce pumpage over the long term.”
The conservation district, partnering with Texas State University and Texas Disposal Systems, is looking for $600,000 for the first experimental phase of the plant which would cost more than $1 million overall.
El Paso is home to the world’s largest inland desalination plant, which went online in 2007. It cost the city about $90 million to build. It has, however, had positive effects on the local aquifer.
“The aquifer has stabilized,” said Karol Parker, communications director for the El Paso Water Utilities. “It’s no longer going down. In some instances, we actually have seen a rise in level of the aquifer.”
Scientists at the Barton Springs Edwards Aquifer Conservation District say if the plant is permanently built and successful it could pump 10 million gallons of water a day, or enough for about 25 thousand households. But figuring out how to do that, and the cost of building a new plant would not be the only hurdles. There is also the question of what to do with the left over water. After desalination, about 25% of the water is too salty to use and can be difficult to get rid of.
“You can discharge into the sea yes, but if you are in Barton Springs, you know the pipeline to take it to the sea would be too expensive,” said Tom Pankratz, editor of the Water Desalination Report.
According to Pankratz, other options include pumping the waste back into a salty aquifer that’s not used, into an abandon oil well, or into a waste-water treatment plant for further treatment. The Conservation District says if it can’t raise the money for the experiment with grants, it may begin the project without grant funding.
Ben Freed contributed to this report.