Waymo's Third Recall Since February 2024 Covers Entire 3,791-Vehicle U.S. Fleet After Flooded-Road Software Defect

Headline Finding

Waymo filed a voluntary recall with NHTSA on April 30, 2026, covering its entire U.S. robotaxi fleet of 3,791 vehicles — its third recall since February 2024 — after a software defect allowed an autonomous vehicle to drive into a flooded, impassable roadway in San Antonio on April 20, 2026, where it was swept into Salado Creek. The recall spans vehicles equipped with both fifth- and sixth-generation automated driving systems across all six of Waymo’s operating cities. The incident exposes a critical gap between hazard perception and appropriate action in the ADS stack, and the absence of a permanent software fix — with the fleet continuing to operate under an interim patch — illustrates the governance challenge of regulating a technology whose remediation cycle runs through over-the-air updates rather than physical service interventions.

Detail

On April 20, 2026, an unoccupied Waymo robotaxi in San Antonio encountered what NHTSA described as “an untraversable flooded section of a roadway.” Rather than routing around the hazard, the vehicle proceeded into the floodwater at reduced speed and was swept into Salado Creek; no passengers were aboard and no injuries were reported, but the vehicle had to be recovered from the waterway days later. A separate incident in Austin, Texas, involved occupied Waymo vehicles driving onto a flooded street and stalling, requiring other drivers to navigate around them.

Waymo filed the voluntary recall with NHTSA on April 30, 2026. It covers 3,791 vehicles equipped with both fifth- and sixth-generation automated driving systems operating in Phoenix, San Francisco, Los Angeles, Austin, San Antonio, and Atlanta. NHTSA documents confirm Waymo is still “developing the final remedy for this recall,” meaning no permanent software fix has been deployed. As an interim measure, Waymo tightened operational parameters by increasing weather-related constraints and updating map data to restrict vehicle access to roads that may be affected by flooding. The final remedy will be delivered as an over-the-air software update, requiring no vehicle to visit a service center.

This recall is Waymo’s third since February 2024. The first, in February 2024, followed two robotaxis in Phoenix separately striking the same improperly towed pickup truck. The second, in May 2025, covered 1,212 robotaxis over collisions with stationary roadway barriers such as chains and gates, following a NHTSA preliminary evaluation citing at least seven incidents between December 2022 and April 2024. Separately, NHTSA has an open investigation after a Waymo robotaxi struck a child near an elementary school in Santa Monica, California, on January 23 (year not specified in source), while the vehicle was running on Waymo’s 5th Generation ADS with no human safety supervisor present. As of April 2026, the Austin Independent

School District had documented at least 24 instances of Waymo vehicles illegally passing school buses during the 2025–2026 school year, including incidents that occurred after a software update was deployed; the National Transportation Safety Board has opened a separate investigation into those violations. Waymo stated that “safety is our primary priority” and that it is working on “additional software safeguards,” including “refining extreme weather operations during periods of intense rain” and “limiting access to areas where flash flooding might occur.”

Governance Implication

1. LEGITIMACY LEVER — DESTROYED: Three recalls in roughly 27 months, two open federal investigations (NHTSA and NTSB), and a documented pattern of school-bus violations accumulate into a legitimacy deficit that cities hosting Waymo operations must now manage politically. Each new incident raises the cost of continued permitting for local regulators.
2. SPATIAL-ALLOCATION LEVER — MOVED: The interim fix — tightening operational design domain parameters and restricting map-data access to flood-prone roads — is a de facto spatial contraction of the service area, imposed by the operator rather than the city. Cities have no formal instrument here; the ODD boundary is being redrawn unilaterally by Waymo, illustrating the absence of city-level curb-management or ODD-approval authority.
3. OTA-GOVERNANCE GAP: The remedy mechanism — an over-the-air software update with no service-center visit — means the fleet continues operating under an unverified interim patch of indeterminate duration. Regulators have no standard instrument to mandate a timeline for finalising the permanent fix, exposing a gap in accountability-architecture that chapter 6 instruments (performance-based permitting, deployment-permit conditions) could close.
4. TWO-CLOCKS READING: The technology clock is running a capability deficit — the ADS can detect a flood hazard but cannot execute an appropriate avoidance response — while the governance clock has not yet produced a framework that would suspend or geofence operations pending a verified permanent fix. NHTSA’s reliance on voluntary recall and OTA remediation leaves the public bearing interim risk.
5. PACING PROBLEM EVIDENCE: The accumulation of three recalls, two federal investigations, and 24 documented school-bus violations within a single operating season is direct evidence of the pacing problem (chapter 1): deployment has outrun both the maturity of the ADS stack and the regulatory infrastructure needed to enforce corrective timelines.

Sources

https://www.jnylaw.com/blog/waymo-recalls-nearly-3800-robotaxis-after-one-drives-into-flooded-road/ https://www.nhtsa.gov/vehicle/2026/WAYMO/JAGUAR%20I-PACE/SUV/AWD https://techcrunch.com/2026/04/30/waymo-recalls-entire-us-robotaxi-fleet-after-vehicle-drove-into-flooded-road/