Construction at Bainbridge Island substations

Project overview

In the coming years, PSE will upgrade our three substations on Bainbridge Island to improve electric reliability and capacity for the Murden Cove – Winslow 115 kV transmission line.To provide safe, reliable energy during construction, we will work on one substation at a time. We plan to follow this general construction schedule:  

  • Port Madison Substation (2023/24)
  • Murden Cove Substation (2025/26)
  • Winslow Substation (2026/27)

This schedule could change, depending on permit approvals and the progress of construction. Please read on for more information about construction at each substation. 

Port Madison Substation

Serving approximately 4,140 customers

Originally built in 1954

New transmission line and improvements in 2000

Port Madison Substation (2023 – 2024) 

In 2023, we replaced some aging equipment at the Port Madison Substation. We are completing the substation’s upgrades in spring/ summer 2024.  

Murden Cove Substation

Serving approximately 4,850 customers

Originally built in 1979

Murden Cove Substation (2025 – 2026) 

We plan to upgrade the Murden Cove Substation in 2025 and 2026. Currently, we are in the early stages of design and permitting. 

The schedule for these activities could change. We will provide more information as construction approaches.

Winslow Substation

Serving approximately 3,980 customers

Originally built in 1960

Winslow Substation (2026 – 2027) 

We plan to upgrade the Winslow Substation in 2026-2027 to support the new Murden Cove-Winslow 115 kV transmission line. We will provide more information as construction approaches.