After four lightning strikes on a local utility grid on 17 August, Google reported that one of its data centres in St. Ghislain, Belgium, suffered a power outage that led to "some" permanent data loss.

A Google Cloud Status notification said that "some Standard Persistent Disks in the europe-west1-b zone began to return sporadic I/O errors to their connected GCE instances" and that "approximately five percent of the Standard Persistent Disks in the zone experienced at least one I/O read or write failure during the course of the incident."

Following a data recovery operation, Google determined that less than .000001 percent of total disk space was still affected, resulting in permanent data loss.

Google said it is replacing storage hardware "to improve cache data retention during transient power lost," and that users should replicate data in multiple locations because storage options are "unavoidably vulnerable to datacentre-scale disasters."