On December 20, San Francisco experienced a large-scale power outage that led to Waymo’s self-driving taxi service being halted and caused traffic congestion. On Christmas day, Waymo once again suspended its Robotaxi service in the San Francisco Bay Area due to flash flood warnings, raising concerns about the ability of autonomous vehicles to handle major unexpected events such as earthquakes and floods.
The power outage was caused by a fire at a Pacific Gas and Electric Company (PG&E) substation, resulting in approximately one-third of the city being left without power, causing traffic signals to malfunction.
Videos shared on social media depicted Alphabet’s Waymo self-driving vehicles stranded at intersections throughout San Francisco, with their hazard lights flashing helplessly. Waymo was forced to suspend operations, only to resume a day later.
In the wake of the incident, which saw other companies like Tesla and Amazon’s Zoox vying to expand their self-driving taxi services in various cities, there have been renewed calls for stricter regulations on this rapidly growing industry.
Computer engineering professor and autonomous technology expert Philip Koopman from Carnegie Mellon University told Reuters that there were errors in responding to the power outage and failure to address this by regulatory agencies would constitute negligence.
Waymo issued a statement on December 23, explaining that while its driving system is designed to treat non-operational traffic signals as four-way stops, it occasionally requests confirmation checks to ensure the safest decisions are made.
Despite successfully navigating over 7,000 non-operational signals on the day of the incident, Waymo explained that a spike in confirmation requests due to malfunctions led to delays in response, exacerbating the already congested streets.
Autonomous taxi operators worldwide rely to varying degrees on remote teleoperation to monitor their vehicles. Waymo, for instance, has a human “Fleet Response” team that addresses specific situations encountered by its robotic drivers.
Missy Cummings, director of the Autonomous and Robotics Center at George Mason University and former advisor to the US road safety regulatory agency, noted the limitations of remote assistance and stressed the need for standardized use of this technology by autonomous taxi operators.
Regulatory bodies in California, such as the Department of Motor Vehicles (DMV) and the Public Utilities Commission, responsible for overseeing and issuing permits for testing and commercial deployment of autonomous taxi services, have initiated investigations into the incident.
DMV is working with Waymo and other self-driving car manufacturers to discuss emergency response measures. The agency is also in the process of developing regulations to ensure that remote monitors meet high standards of safety, accountability, and response time.
Cummings and Koopman both advocated for additional licensing requirements for operators of autonomous taxi fleets to ensure they are adequately equipped to handle large-scale malfunctions as the scale of self-driving taxi fleets grows.
Koopman warned, “This is just a warning; luckily, it wasn’t an earthquake, or it would have been a big problem.”
The deployment of fully autonomous vehicles and achieving commercialization has proven to be much more challenging than anticipated, requiring substantial investments to ensure the safety of the technology. Strong public backlash following accidents has forced many companies to shut down operations.
In 2023, General Motors faced scrutiny after a Cruise autonomous taxi struck a pedestrian, leading regulators to revoke its operating license, ultimately resulting in the company ceasing operations.
Waymo, originally launched in 2009 as a project under Google, became an independent company under Google’s Alphabet in 2016, steadily expanding its fleet to over 2500 vehicles operating in San Francisco Bay Area, Los Angeles, Phoenix metropolitan area, Austin, and Atlanta.
Recent expansions in the North Bay and East Bay regions have been approved by the DMV, allowing for testing and deployment operations in multiple cities. Waymo plans significant service expansion in the US and abroad by 2026.
The company stated that its current confirmation protocols, devised during the initial deployment phase, will be refined to accommodate its current scale. Upgrades are planned for all its self-driving taxis to enable “more decisive navigation decisions in blackout situations.”
Additionally, Waymo intends to enhance emergency preparedness plans and improve communication with municipal officials and emergency responders.
On Christmas day, due to flash flood warnings issued by the National Weather Service (NWS), Waymo once again announced the suspension of its Robotaxi service in the San Francisco Bay Area.