A broken cross-arm on a utility pole caused a significant power outage in Sarnia Monday morning.
Bluewater Power says the problem originated on Murphy Rd. near Afton Dr. and Kensington Blvd.
Utility spokesman Chris Gould says 5,000 customers were initially impacted, generally in the Murphy Rd. and London Rd. area.
About half were brought back on line in fairly short order.
He says 100 or less customers were without power until early afternoon as crews fixed the cross-arm.
The cause of the failure will be investigated.