GCP us-west1 outage: scheduled maintenance took down 20+ services

On August 20, 2026, planned fiber maintenance in Google Cloud's us-west1 region reduced inter-datacenter network capacity, and automated rerouting failed to redistribute traffic. The 2-hour-22-minute incident affected more than 20 products, including Compute Engine, GKE, Cloud Storage, IAM, BigQuery and Pub/Sub.

• Planned fiber maintenance in us-west1 began at 08:00 Pacific on August 20
• Automated rerouting failed to redistribute traffic, and the region began to congest
• More than 20 services were affected across control-plane and data-plane operations
• Google advised failing over to other regions while IAM was also listed as degraded