San Antonio has plenty of water to serve its residents and businesses despite the lingering drought, San Antonio Water System staff told board members Tuesday. However, as the region’s growth continues, the utility will have to grow its water resources to keep pace, officials said.
SAWS staff presented the first draft of the utility’s 2024 Water Management Plan to its board, a belated edition of SAWS’ five-year water management plan that outlines new projections for the region’s growing water needs and how the utility plans to address them. The utility’s updated plan accounts for more intense weather from climate change, San Antonio’s booming population, the region’s economic growth and residents’ continued efforts to conserve.
While the utility’s 2017 Water Management Plan, the most recent iteration, based SAWS’ water management goals on a “hybrid drought” that combined the worst characteristics of Texas’ drought of record from the 1950s and the region’s 2011-2014 drought, the updated plan bases the utility’s goals on weather that is even drier and hotter, said Donovan Burton, senior vice president of water resources and governmental relations.
“We normally [update the plan] every five years …. [but] we actually chose to wait a bit longer because in ’22 and in ’23 we faced historic drought and we thought it would be good to use the historic drought [conditions] in our actual plan to make sure to challenge our assumptions,” Burton said. “We learned some very important lessons — some of them very hard, some of them very good.”
Lessons learned over the past two extremely hot, dry years have helped SAWS to create a more comprehensive drought plan, Burton said, adding the plan still also factors in flexibility for unforeseen circumstances.
“We think a lot of our future supplies can come from either expanding what we already have in place, or from our own projects that we have coming up,” he said. “We are also exploring other projects with other agencies.”
The utility aims to finalize the draft of the plan by March 1. The updated plan will require approval by the SAWS board of trustees and the San Antonio City Council before it can go into effect, officials said.
Thirsty for growth
While San Antonio residents and businesses have gotten better at conserving water over the past four decades, growth — both of the area’s population and economy — is driving up the region’s demand for water, said SAWS Manager of Water Resources Steven Siebert.
San Antonians have decreased the gallons per capita per day they use by roughly half since 1982, from 225 gallons per capita per day to roughly 122 gallons per capita per day in 2022. However, region-wide demand for water has been steadily rising over that same time period and is expected to continue to grow over the next five decades, Siebert said.
While the 2017 plan accounted for growth, its population projections were somewhat off, Siebert noted. The 2024 plan accounts for even faster growth than SAWS previously projected.
A changing climate that is experiencing more intense bouts of heat, drought, cold and flooding is also driving a need for more water as the utility works to shore up water in its aquifer storage and recovery (ASR) system, Siebert said. An aquifer storage and recovery system works like an underground water bank, where a utility can store extra water during times of plenty so it can access that water during times of drought.
SAWS foresees it will likely need to use water from its aquifer storage and recovery system in the future to meet gaps between demand and supply, which requires growth of the system and its reserves, Siebert explained.
“We’ve gotten a very good ability to see how the ASR works these past couple of years,” Burton told the board. “We put that into the [new] supply model.”
Expanding existing sources
SAWS plans to manage for forecasted gaps by expanding several of its existing sources, Siebert said.
Echoing its sister utility CPS Energy, which is actively expanding its generation portfolio to keep up with local growth, SAWS will continue to strive to make conservation its leading “new source,” Siebert said.
The utility has updated its conservation plan to reflect new strategies and techniques, including more proactive leak detection through replacing older water mains and leveraging new smart meter data to spot leaks quickly, he said. The utility has also expanded and updated its drought restrictions to discourage extra water use during periods of severe drought, and has closed several loopholes heavy irrigators were using to pay less for water.
Should severe drought conditions continue as they have for the past two years, SAWS could be up against its first demand-versus-supply gap in 2035 and 2036, according to its latest projections. It plans to plug this by expanding its water supplies from the Carrizo Aquifer, Siebert said. Under these conditions, a second gap could happen in 2042 and another in 2056.
SAWS plans to expand its brackish water desalination operations for the Edwards and Wilcox aquifers over the next two decades to meet those gaps, he added. Burton added SAWS may also continue to look for other sources outside of the immediate area, as it did with the Vista Ridge pipeline project, which draws water from Burleson County, to meet demand if it “makes the most sense.”
“However, it’s good to know that we do have our water future in our hands with those other supplies that we already have in place,” he said.
