It's believed a medical issue caused a single-vehicle collision on London Line Saturday afternoon.
Sarnia police say a vehicle was heading westbound when it left the roadway and struck two poles.
The driver, a 66-year-old from Sarnia, was taken to hospital for treatment of non-life threatening injuries.
No charges are being laid.
The crash knocked out electricity to nearby Bluewater Power customers.
London Line was closed between Waterworks Rd. and Brigden Rd. for several hours while utility crews made repairs and the crash scene was cleared up.