Waymo said it was pausing its driverless taxi service in six cities in Texas, Tennessee and Georgia amid concerns that its cars might drive into flooded roads.
The temporary shutdowns came after the National Highway Traffic Safety Administration said in a letter this month that Waymo was fixing software in thousands of its taxis that could allow the cars to drive into standing water on some roads.
Waymo said it had decided to repair the software last month after an unoccupied taxi entered a flooded road during a heavy downpour in San Antonio on April 20. Earlier this month, Waymo said the software could be fixed without interrupting taxi service.
But on Friday, Waymo, which is owned by Alphabet, the parent company of Google, confirmed that it was temporarily suspending taxi service in Austin, Dallas, Houston, San Antonio, Nashville and Atlanta. There have been strong storms in those cities, some leading to flash floods.
The company took the action after videos emerged showing that two Waymo cars had stopped on flooded roads in Atlanta on Wednesday, when the city received 2 to 3.5 inches of rain, inundating some streets and the Downtown Connector, a highway in the city core.
Waymo said that while its cars can drive in heavy rain, it wanted to improve service. It said it expected to resume taxi operations in the six affected cities soon.
Separately, Waymo said it was temporarily pausing the ability of its taxis to travel on highways as it works to improve the way they navigate certain highway construction zones. It said it expected to restart that service — which it offers in Miami, Phoenix, Los Angeles and the San Francisco Bay Area — soon.
“We are committed to being good neighbors for our riders and our communities,” Chris Pappas, a Waymo spokesman, said in a statement on Friday. “As part of that commitment, we make proactive decisions including temporarily pausing aspects of our service.”
One of the videos from Atlanta was posted by The Atlanta Journal-Constitution and recorded by one of its journalists, Rachael Knudsen. She told the paper that the Waymo car she was riding in amid heavy rain on Wednesday drove onto several flooded streets and then “gave up.” She had to order an Uber to get home instead. (Uber and Waymo have a partnership and share some services in Atlanta and other cities.)
Ms. Knudsen said she wasn’t sure she would ride in a Waymo taxi again in bad weather.
“I was taken aback at how the Waymo was not able to sense the water that was ahead,” she told the paper.
A second video showed a different Waymo car stopped on a flooded Atlanta street on Wednesday, in water almost up to its headlights. Waymo said the vehicle was unoccupied at the time.
The incidents came as self-driving cars have proliferated in major American cities, giving people a new way to get around while also resulting in safety concerns.
Waymo is facing federal investigations into traffic violations, and the company said it planned to update its software last year after reports that its taxis had illegally passed stopped school buses.
Its cars have also been involved in more serious incidents, including instances in which an ambulance was blocked from getting to the scene of a shooting in Austin, a cat was killed in San Francisco and a child was struck in Santa Monica, Calif.
Waymo says it provides half a million fully autonomous trips to riders across the country every week. The company said its technology statistically outperforms human drivers, reducing the chance of crashes and serious injuries.
“Safety is Waymo’s top priority, both for our riders and everyone we share the road with,” Mr. Pappas said.
