Cause of overnight power outage unknown

Seattle City Light is looking into the cause of a power outage that affected thousands of residents in Fremont and Ballard overnight.  We received several messages via email and in the forum indicating that power went out around midnight.  Power was restored within an hour and a half.  The problem appears to have occurred at the Canal Substation but details are unclear for now.  Workers are at the substation today to determine what happened.