Waymo’s autonomous cabs have logged millions of miles navigating complex city streets. Last week in Austin, one was defeated by a small pool of water.

A new clip shows the moment a Waymo became flummoxed by a small puddle on Austin’s North Lamar Boulevard, a busy thoroughfare connected to the city’s downtown.

A clip shared by FOX 7 Austin shows the Waymo stalled out on the left side of a two-lane road, refusing to get its tires wet in a small puddle under and overpass. Taking up an entire lane, the Waymo forces traffic to converge around it while it sits in a daze.

“You need a human being behind the wheel to determine all the situations that can occur,” one witness named Kelly Reich told local reporters.

“I would be a little upset about it, especially if I was in that traffic, trying to go around that thing,” Reich continued. “And I’d be a lot more upset if I was in the car wondering, okay, this car does not know what to do. What do I do? I’m stuck here.”

Waymo didn’t respond to FOX 7‘s request for comment.

The event occured during a particularly nasty rain storm, which flooded city streets and created dangerous conditions in local waterways. At least one person was found dead in San Marcos, a town south of Austin. The conditions present in that video didn’t seem too bad, making it anyone’s guess why the Waymo got cold feet.

Another clip from the storm shows at least two Waymos venturing into a flooded stretch of road in Austin’s south east side, eagerly fording the puddles before getting spooked and stopping right in the water. The rather inconsistent approach to flood management raises urgent questions about edge cases: how far can you trust Waymos to keep you safe in hazardous flood conditions?

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