Sedro #4 transmission line and substation upgrade

Phase D

• Lake Samish Park to Bellingham substation (6 miles)
• Norlum substation to Sedro Woolley substation (1.5 miles)

We expect to begin working on this segment in spring 2026. Check back for project updates or contact us with questions.

Project overview

To increase electric reliability for customers in Skagit and Whatcom counties, we are rebuilding and reconductoring approximately 25 miles of existing transmission and distribution lines between Bellingham and Sedro Woolley.

Currently, the local electric system is prone to power outages due to limited capacity and aging infrastructure. The existing poles and conductors (wires) were built in the early 1960s and need to be replaced. Rebuilding these transmission and distribution lines with new, higher capacity wire and replacing the poles will strengthen the current system and reduce the frequency of outages for our customers in the area.

The overall project work will be completed in phases

All phases of this project include replacing the existing structures with new wood poles and new, higher capacity 115 kV transmission wire. It also includes replacing distribution wire as needed.

Phase A: Complete 2017
Alger to Belfast (4 miles)

Phase B: Complete 2018
Prairie Road near Belfast to the Norlum substation in Sedro Woolley (7.5 miles)

Phase C: Complete 2025
Lake Samish Park to Alger transmission line (6 miles)

Phase D: Upcoming spring 2026
Bellingham substation to Lake Samish Park (6 miles)
Norlum substation to Sedro Woolley substation (1.5 miles)