Nearly 4,000 of Waymo’s autonomous taxis were recalled after the company’s software may have allowed the vehicles to drive into flooded roads, according to a letter from the National Highway Traffic Safety Administration obtained by NBC Chicago. Both the fifth- and sixth-generation Waymo mode ls were subject to the recall, according to NHTSA. A total of 3,791 of the autonomous taxis were recalled. The recall was issued after a Waymo in San Antonio entered a flooded lane during extreme weather. The vehicle was empty at the time; however, the incident led Waymo to review its technology, specifically in scenarios involving both high-speed areas and flooded roadways. “The software may allow the vehicle to slow and then drive into standing water on higher speed roadways,” NHTSA said in the letter that was addressed to Waymo Senior Director Matthew Schwall. A remedy to the software issue is “currently under development,” according to NHTSA. Waymo has modified the scope of its operations to “increase weather-related constraints and updated vehicle maps” as an interim remedy, the agency added. “We have identified an area of improvement regarding untraversable flooded lanes specific to higher-speed roadways, and have made the decision to file a voluntary software recall with NHTSA related to this scenario,” Waymo said in a statement. “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.” Waymo rolled out in Dallas in late February. “Entering a flooded roadway can cause a loss of vehicle control, increasing the risk of a crash or injury,” NHTSA said in the letter. More than half of flood fatalities are vehicle-related, according to the National Weather Service. During severe storms in North Texas that prompted flooding in recent weeks, NWS repeatedly warned residents to not risk driving into floodwaters. It only takes six inches of water to reach the bottom of most passenger cars, causing loss of control and possible stalling, according to NWS. A foot of water will float many vehicles, and 2 feet of rushing water can carry away most vehicles, including SUVs. Avride, another robotaxi operator in Dallas, is also under investigation by federal agencies for incidents reported in Dallas. This story uses functionality that may not work in our app. Click here to open the story in your web browser. ...read more read less