Deadly floods prompt $20M flood alert system in San Antonio

This past June, San Antonio mourned the loss of 13 residents who were swept from roads during a record rainfall event that brought creeks, rivers, and even highways to dangerous water levels. Roughly one month later, at least 134 were confirmed dead after monstrous floods hit the Texas Hill Country, which began during the early morning hours on Friday, July 4, and destroyed children’s camps along the Guadalupe River.

Both tragedies sparked questions about whether Texas lawmakers were doing enough to protect those living in high-risk flood zones. In June, then San Antonio Mayor Ron Nirenberg and County Judge Peter Sakai formally requested state assistance from the Governor’s Office, asking for help in restoring and stabilizing infrastructure damaged or impacted by the early summer storm. 

“The magnitude of this disaster requires state-level support,” Mayor Nirenberg said at the time. “Our community is resilient, but we cannot do this alone.”

In Comfort — an area hardest hit by July 4 flooding — a coalition of land and water conservation organizations met last month, urging representatives to impose stricter floodplain protections, smarter land use, and science-backed strategies for when another storm inevitability hits what’s described as the “Flash Flood Valley.” Last month, the groups urged lawmakers to consider keeping floodplains undeveloped, upgrading infrastructure, and ensuring coordinated, watershed-wide planning ahead of the special legislative session that began on Monday, July 21, and is still ongoing.

Meanwhile, the City of San Antonio, Bexar County officials, and the local river authority have released new details about their plan to save lives when flash flooding returns to South-Central Texas.

In a news release issued on Tuesday, August 5, the entities announced a $20 million investment into a “Next Generation (NextGen) Flood Warning System and Resilient Infrastructure Program,” which is designed to “bring technology, modern infrastructure, and public outreach together, to save lives during future storms.”

The new system uses real-time data from San Antonio area gauges and sensors to send faster and more accurate flash flood alerts to residents, thus providing first responders and the general public with more time to act. 

“The goal is for zero lives to be lost during a major flood event,” Sakai said in the release. “This new system, coupled with a robust outreach campaign around flood awareness and safety, ensures Bexar County residents have the tools they need to stay safe.”

It also involves the contribution of the San Antonio River Authority, which will update floodplain maps and models, and add more sensors in the region to track flooding as it happens. The hope is that this will result in more precise and predictive alerts for locals, informing them of what areas to avoid. When the system rolls out, the river authority will be responsible for inspecting, monitoring, and maintaining it to ensure it works when the community can’t afford it to fail.

“By working together with Bexar County and the San Antonio River Authority, we’re taking action to protect residents before the next storm hits. This is local leadership stepping up for public safety,” current Mayor Gina Ortiz Jones said.

Other elements of the plan include installing low-water crossing barricade gates, hosting regular flood awareness public meetings, and ensuring the project budget meets the persistent, ongoing needs of the region.

A map of the Bexar County Watershed Area that may be updated is included below.

A presentation created by the organizations lists the following goals for the new system: Reduce or eliminate the need for water rescues at low water crossings, improve the early warning system, remove structures from floodplains and floodways, and create more resilient systems for future conditions.

A series of public meetings will occur over the next six months to educate people on the new system. Additionally, a region-wide flood safety education campaign will happen in 2026 to promote a culture of flood awareness and preparedness, the news release states. Folks can follow the City of San Antonio’s Instagram account for additional updates.