Waymo is recalling thousands of its self-driving cars in the US over a software issue that could allow vehicles to drive into flooded roads.
According to a letter posted on the National Highway Traffic Safety Administration (NHTSA), external website on Tuesday, the voluntary recall affects nearly 3,800 robotaxis that use the company’s fifth and sixth-generation automated driving systems.
It follows an incident on 20 April in San Antonio, Texas, where an empty Waymo vehicle entered a flooded road and was swept into a creek.
The company, which hopes to be operating a robotaxi service in London by September, said it was working on “additional software safeguards”, according to CNBC.
The BBC has contacted Waymo, which is owned by Google’s parent company Alphabet, for comment.
Waymo’s San Antonio service also remains temporarily suspended following the incident, though the company said it will resume public rides after the necessary software fix had been rolled out.
According to the NHTSA letter, temporary updates limiting where affected vehicles can drive during extreme weather have already been applied.
Waymo says it now provides more than 500,000 trips per week, external across multiple US cities including San Francisco, Austin and Miami.
Jack Stilgoe, professor of science and technology policy at University College London, told the BBC that all self-driving car systems had limits on when and where they could operate safely.
“We often see these limits only when something goes wrong,” he said.
As more autonomous vehicles are deployed, Prof Stilgoe said, more such problems are likely to emerge.
“That isn’t to say the technology won’t be hugely beneficial,” he added.
“But policymakers would prefer to know about these things in advance rather than discovering them in hindsight.”
Over the past year several incidents with different driverless car firms have raised concerns over robotaxi safety.
In December 2025, a large power outage in San Francisco led Waymo taxis to stop working around the city, causing significant disruption.
And in April, a mass Apollo Go robotaxi outage in the Chinese city of Wuhan caused at least a hundred self-driving cars to stop mid-traffic.
