Sign up for TPR Today, Texas Public Radio's newsletter that brings our top stories to your inbox each morning.
San Antonio Water System President and CEO Robert Puente is defending the utility’s handling of two high-profile issues: the Guajolote Ranch wastewater treatment plant controversy and the potential relocation of the SAWS downtown water chiller as part of Project Marvel, the city’s planned downtown redevelopment and sports-entertainment district.
During an interview on TPR’s The Source, Puente said SAWS has negotiated what he called “some of the strictest safeguards in Texas” for the proposed wastewater facility tied to the 1,100-acre Guajolote Ranch development near Helotes.
The project, led by Lennar Homes, has sparked widespread concern among residents and environmental groups who warn that wastewater discharge into the Helotes Creek watershed could degrade the Edwards Aquifer, San Antonio’s main drinking water source.
Puente acknowledged those concerns but insisted the risk has been minimized. “We have negotiated nine different concessions,” he said. “Along with the geology of the area, it’s very unlikely that discharged water would make it to the Edwards Aquifer.”
He added that much of the treated water would be reused on-site for irrigation, and that SAWS required “enhanced treatment, increased filtration, and nutrient removal.” He said this makes it one of only two wastewater plants in Texas with that high level of discharge quality.
A Southwest Research Institute study commissioned by the City of San Antonio previously warned that any discharge into Helotes Creek could harm aquifer recharge water quality. Puente disputed that interpretation, saying, “It did not say 'any' discharge. It said certain 'types' — those without the safeguards we have required here.”
Puente also addressed questions about what might happen during major rain events, when treatment plants can overflow. He said the agreement requires the developer to build a “wet well” — a 24-hour holding system designed to contain wastewater before release.
The SAWS chief also sought to reassure listeners that San Antonio has a sufficient water supply to serve growing developments despite ongoing drought conditions. “We have calculated that the growth we’re going through and the amount of water we have will meet that demand,” he said.
Puente also discussed Project Marvel, the city-backed downtown redevelopment plan that could include a new hotel where the SAWS Commerce Street water chiller plant currently sits. The facility is part of a unique underground system that cools water to near freezing and circulates it through major downtown buildings for air conditioning.
He said no decision has been made about relocating the plant, despite speculation about a $200 million price tag. “We don’t even know if we have to move,” Puente said. “There are no engineering plans or design plans. The number came from comparisons with other cities — it’s not something anyone should rely on right now.”
If a move is eventually required, Puente said, it would not affect SAWS customers’ water rates because the chiller system is a separate business unit funded by its commercial clients. “Residential and commercial water customers would not pay for that,” he emphasized.
Puente said any move would likely be years away and tied to how the city phases its Project Marvel construction. “We have plenty of time to figure out what’s going to happen next,” he said.
