Flood safety / Driving
Low water crossings and flash floods are a real danger in Bexar County
San Antonio and Bexar County have many low water crossings that can flood with little warning—12 to 18 inches of moving water can sweep away most vehicles.
Flash floods are among the most deadly weather hazards in Bexar County. San Antonio sits in the Texas Hill Country's 'flash flood alley,' where heavy rain upstream can make a dry crossing rise to dangerous levels in minutes. More than half of all flood deaths nationwide involve vehicles driven into flooded roadways.
Bexar County operates 150 HALT (High Water Alert Lifesaving Technology) locations throughout the county. Sensors detect rising water and trigger color-coded signals: green means the crossing is safe, yellow means water is rising, and red means the road is closed. You can view real-time crossing conditions at SARiverFlood.org or sign up for text alerts. The county worked with the San Antonio River Authority to expand and upgrade this system in 2026.
The rule is simple: Turn Around, Don't Drown. Barricades at flooded roads are there for your safety. Driving around them is illegal and dangerous. If you see water over a road, do not cross. Check current closures at sa.gov/floods before traveling during heavy rain.
Source to confirm: Bexar County – Turn Around, Don't Drown