Bexar County approves up to $1.25M in state funds to add flood-warning sirens, moves forward on NextGen system

Bexar County’s commissioners on March 31 approved a resolution to accept financial assistance from the Texas Water Development Board and authorized the county judge to execute a grant agreement for up to $1,250,000 to support installation of sirens and upgrades to the county’s NextGen flood-warning system.

The court’s vote followed a presentation by the San Antonio River Authority (SARA) and county staff outlining work already completed — surveys of high-water detection locations, a risk assessment, and preliminary predictive modeling — and a plan to phase site selection, design and installation. Erin Cavazos of SARA told the court, “1,250,000 will not be enough,” and said the grant would fund an initial design and installation phase aimed at roughly five to 10 sirens while staff pursue additional funding to cover the full flash-flood-prone area identified by the state.

Why it matters: Commissioners said the project is intended to reduce loss of life and improve real-time public safety messaging during flash floods. SARA and county staff said the NextGen program combines additional gauges, predictive flood modeling, two-way communications hardware (gates, lights, cameras) and public-outreach campaigns to reach drivers and residents. The program’s timeline calls for a May capital-plan return to the court and design/implementation through summer, with a goal of system completion by September 2027.

Details and debate: Staff described three principal elements: (1) finishing a countywide inventory of gauges and prioritized new gauge locations; (2) adding redundant power and communications at siren/gauge sites to meet state requirements; and (3) a regional communications strategy (including sariverflood.org and targeted billboards) to change driver behavior. Cavazos said the state’s preliminary maps identify about 800–900 stream miles of flash-flood-prone area in Bexar County and that the Senate Bill 3 requirement for sirens applies to those provisional zones.

Commissioners pressed on several points: whether the city of San Antonio would apply separately (staff said funding is allocated by county and the plan includes municipalities), how to prioritize sites with prior flood fatalities (staff said the NextGen program focuses on where people are exposed, including campgrounds and overnight sites), the potential need to negotiate easements or compensation for placing sirens on private campgrounds, and the plan for Spanish-language and microtargeted outreach in communities that rely on local news outlets. Dave Wegman of county public works stressed the broader, ongoing capital-planning process for flood-control infrastructure and said the siren project is one element of longer-term mitigation work.

The court approved the resolution by voice vote, with no recorded roll call. The grant agreement authorizes the judge to execute documents tied to the award and to pursue implementation in phases; staff said the TWDB requires final invoices to be submitted by August 2027. Next steps include returning to the court in May with a capital plan and a request for a supplemental interlocal/ILA to move into design and implementation.