With a burgeoning population in Central Texas, drought-proof water supplies will be depleted in the next two decades, according to a recent bill, Senate Bill 1532, introduced by Texas Sen. Judith Zaffirini (D-San Antonio). The companion bill in the House was HB 340.
New water supplies to meet the region’s growing demand are scarce and increasingly expensive. But two emerging technologies, desalinization and aquifer storage and recovery (ASR), could pave the way for new water supplies.
Desalinization would involve the unsalting of water from the brackish part of the Edwards Aquifer, which is the region’s primary groundwater supply.
ASR is a process of moving fresh water reserves into salinated parts of the aquifer for temporary storage.
Zaffirini’s SB1532 amends current law relating to the power of the Texas Commission on Environmental Quality (TCEQ) to authorize certain injection wells that transect or terminate in the Edwards Aquifer. With that barrier removed, it allows a test well or wells to gather empirical data on the effects of desalinization on the aquifer as well as the effects of ASR.
According to Kirk Holland, general manager and chief operating officer (COO) of the Barton Springs Edwards Aquifer Conservation District (BSEACD), this new legislation may provide the region with much needed new reserves of water.
“We’re doing some pioneering here,” he said.
The district seeks to find ways to reduce dependence on the Barton Springs segment of the Edwards Aquifer, especially during extreme drought.
An ad hoc Stakeholder Advisory Committee (SAC) created by BSEACD helps guide policy, research and management decisions concerning alternate water supplies. Kyle’s Utility Coordinator Jason Biemer sits on the committee, as does Stanley Fees, Buda’s city engineer, Daniel Meyer, Plum Creek Conservation District, Tim Miller of Millberg Farm in Kyle and Joseph Marini of Texas Lehigh in Buda.
Hays County residents Don Inbody and Matthew Scott are also members.
Through a survey and in-person meeting, the committee ranked priorities for alternate water supplies. The group most highly recommended developing the science required for alternate water supply feasibility studies (81.3 percent). It’s next highest priority was encouraging conservation and use of other alternate supplies (62.5 percent).
Desalinization is one possible solution to water scarcity. But the process is not without drawbacks, Holland said.
The by-product of desalinization is brine. Under a 2001 law, SB. 2, 77th Legislature, the aquifer’s fresh water was protected from “any injection of water that has been physically, biologically or chemically altered either into or through the Edwards Aquifer anywhere in Travis and Hays Counties, without any distinction between whether the Edwards water is fresh or brackish/saline.”
Essentially, that law prohibits putting the brine back into the aquifer. But Holland said the brine has to go somewhere. He said HB 1532 takes baby steps toward getting the prohibition against desalinization removed.
During the SAC’s meeting, one of the subcommittees cautioned that desalinization plants are very costly to decommission.
“Australia is having a big problem with decommissioning now that it is a rainy period,” they wrote.
With the new law in place, it opens the door for a test site, which is outside BSEACD’s jurisdiction. Texas Disposal Systems (TDS) in Creedmoor, just east of Buda, will be the site of a pilot test to gather evidence of whether the process is harmful to the aquifer or not.
The benefit to TDS, which would bear the cost of drilling and maintaining the test well or wells, is an additional water supply for its waste management, recycling and composting operation. Holland said the wells would need to be 1,500 to 1,800-feet deep for this kind of test, making them an expensive investment in research and development.
Because it is outside the district, Holland said the 1,700 acres owned by TDS is a good site for this kind of data gathering.
Two possible alternatives to putting the brine back into the aquifer are to cultivate it in some form, such as growing shrimp for wholesale distribution, or algae, which can be used as a biofuel, in it.
From a monetary perspective, Holland said, “It’s a pure business decision for TDS. If there’s a buck to be made by reusing or selling the water, they’re going to do that. It’s their business.”
Researchers from Texas State University will conduct an independent evaluation of the demonstration well. The evaluation, Holland said, involves monitoring of the effects of desalinization and modeling of long-term performance. He said organizations such as the Texas Wildlife Federation and the Sierra Club backed the law.
Another emerging technology, ASR, aquifer storage and recovery, may offer the region another source of fresh water. Holland said ASR would take place in the Saline Zone and/or Lower and Middle Trinity aquifers.
Holland said the injection of fresh water into the saline zone creates a bubble that would theoretically protect the fresh water until it’s needed at a later date.
The new law takes effect September 1, 2013.
Zaffirini’s bill defines an engineered aquifer storage and recovery facility to mean “a facility with one or more wells that is located, designed, constructed and operated for the purpose of injecting fresh water into a subsurface permeable stratum and storing the water for subsequent withdrawal and use for a beneficial purpose.”
In layman’s terms, during plentiful times, fresh water would be temporarily stored in the saline parts of the aquifer, which could then be extracted during times of drought.
Correction: an earlier version of this story listed the legislation as House Bill 1532, introduced by Texas Rep. Judith Zaffirini (D-San Antonio) and the companion bill in the Senate was SB 340. The correct bills should be Senate Bill 1532 by Sen. Judith Zaffirinni and the companion bill in the House was HB 340. We regret the errors.