Waymo Recalls Robotaxis After Vehicle Drove on a Flooded Road

Waymo is recalling thousands of robotaxis to fix a software issue that could cause the autonomous vehicles to drive on flooded roads.

The recall affects 3,791 vehicles equipped with the company’s fifth- and sixth-generation automated-driving system, according to documents posted to the National Highway Traffic Safety Administration’s website. The Alphabet Inc.-owned robotaxi business has placed additional constraints on the system’s operations while it works on a permanent fix.

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The problem stems from an incident on April 20, when an unoccupied Waymo robotaxi encountered “an untraversable flooded section of a roadway,” according to the documents. Rather than avoid the potentially dangerous street, the vehicle proceeded into floodwater at a reduced speed.

While no one was injured and the recall is relatively small, the incident highlights the challenges for driverless vehicles to adapt to unpredictable weather and other unexpected roadway conditions without a human driver’s judgment. Waymo has been rolling out its robotaxi service in cities across the US in a growing competition with the likes of Tesla Inc.

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NHTSA has a separate investigation into Waymo’s self-driving vehicles after one of them struck a child near a school in Santa Monica, California, in January.

Top photo: A Waymo autonomous taxi in Mountain View, California. Photographer: David Paul Morris/Bloomberg.