Over 3,200 Bluewater Power customers in north Sarnia and Bright's Grove had the lights go out Sunday morning.
The utility reported an unplanned outage at 9:10 a.m., affecting customers from Mandaumin Road to beyond Modeland Road, and from Lakeshore Road to the Highway 402.
The utility says the cause was animal contact.
Power was restored before 11 a.m.