SAN ANTONIO — Waymo issued a voluntary software recall covering 3,791 autonomous vehicles nationwide after one of its robotaxis drove into high water and was swept away in San Antonio on April 20, 2026. No one was inside the vehicle when it entered the floodwater, which was later recovered from Salado Creek days after the incident.

The recall targeted the software that allowed the vehicle to enter the high water rather than the vehicles themselves. According to materials submitted to the National Highway Traffic Safety Administration, Waymo decided to recall its vehicles for software fixes on April 24 and formally reported the defect to the agency on May 1, 2026. NHTSA acknowledged the recall in a letter dated May 11, 2026.

Federal regulators determined that a software defect in Waymo's self-driving system could allow robotaxis to drive into floodwater. On higher-speed roadways, the vehicles may slow but not stop in response to detecting a potentially untraversable flooded lane, and the defect can result in loss of vehicle control. The recall affects vehicles equipped with Waymo's 5th and 6th Generation Automated Driving Systems.

"Entering a flooded roadway can cause a loss of vehicle control, increasing the risk of a crash or injury," NHTSA said. The agency also flagged that Waymo has not yet provided a permanent fix.

Waymo applied an interim software update to all 3,791 affected vehicles by April 20, 2026. The company imposed tighter weather-related restrictions, updated the maps used by the vehicles, and removed operating conditions that exacerbated the possibility for its vehicles to encounter flooded, higher-speed roadways.

"We are working to implement additional software safeguards and have put mitigations in place, including refining our extreme weather operations during periods of intense rain, limiting access to areas where flash flooding might occur," a Waymo spokesperson said. The company paused local services in San Antonio after the vehicle entered a flooded roadway during heavy rain. Waymo has since resumed autonomous driving operations in the city, but its cars will not transport passengers there until further notice.

Waymo currently operates autonomous vehicles in 11 cities, including San Antonio, Dallas, Houston and Austin, with additional commercial robotaxi services in markets such as San Francisco, Los Angeles and Phoenix. Under federal law, the company must submit eight consecutive quarterly status reports on the recall, followed by three annual reports.