How a looped transmission system will reduce likelihood of outages on Bainbridge Island

On July 15, Bainbridge Island experienced an outage at the Winslow substation. This 4-hour long outage affected a total of 6460 customers and was caused by vegetation that fell into the transmission line that serves the substation, taking out power. Because the substation is only served by one transmission line (called a “single radial transmission line”), if that line is affected, then the substation and all customers served by the substation lose power until crews can make repairs.  
 
If the new Murden Cove – Winslow 115 kV "missing link" transmission line were in place, this outage and its impact to Bainbridge Island customers, would have been prevented. The new transmission line will connect the Murden Cove and Winslow substations, creating a transmission loop. This means each substation will be connected by two transmission lines. If one of the transmission lines goes out, the other transmission line can still feed the substation and provide power to customers while crews make repairs. 
 
PSE continues to advance the planning and development activities for the Murden Cove – Winslow 115 kV transmission line project. Construction is currently anticipated to occur in 2030-2031, however the schedule remains subject to change.
 
Learn more at our website.