Puget Sound Energy electric transmission project
Sedro-Woolley to Horse Ranch 230 kV transmission line
Fall 2009 project update
- Construction began in May 2009
- We anticipate construction to be complete in fall 2010
Project overview
Puget Sound Energy plans to install a new 230 kilovolt (kV) transmission line and fiber-optic line along 40 miles of our transmission line corridor between our Sedro-Woolley substation and our Horse Ranch substation, which is located in Lake Stevens. We will upgrade our existing 115 kV transmission lines, which are currently on wooden H-frame structures, with a new 230 kV transmission line on mono pole structures. In addition, PSE will upgrade Sedro-Woolley and Horse Ranch substations to accommodate the new line. Our new transmission and related fiber-optic lines will increase capacity and improve reliability of the system.
Fiber-optic lines help PSE monitor and coordinate our electric transmission system remotely through instantaneous communication. Currently, PSE manages the existing transmission line through static data points, which require manual manipulation of switches to operate the system—a utility worker has to physically go out to the line to flip the switches. With the fiber-optic line, PSE will have the ability to flip the switches from a remote control room. The new transmission line will help mitigate power outages, and support future growth in the area.
What is a transmission line?
Transmission lines are key elements in the electrical distribution system. The lines safely transport high voltage electricity from power generation sources like dams and wind farms to substations in local communities. Transmission normally takes place at voltages of 55 kV and higher.
What is a fiber-optic line?
A fiber-optic line or optical fiber is a glass fiber that is designed to direct light along its length and is used for communication purposes. The fiber-optic lines used in our electric system are small, half-inch in diameter lines. Fiber-optic is light, less expensive, and able to carry much more information than radio and microwave communication.
Committed to keeping you informed
PSE will continue to provide updates to the community. We will notify residents who live near the project area when construction will occur. It is our aim to complete the work with as little disruption as possible.
Download information
Download the PDF files for more detail on PSE's Sedro-Woolley - Horse Ranch transmission line project.
Construction notice, May 2009 (30 KB PDF)
Survey letter, February 2009 (30 KB PDF)
Meeting invite, February 2009 (354 KB PDF)
Sedro-Woolley-Horse Ranch map (2 MB PDF)
Fact sheet (183 KB PDF)
To view and print the PDF-formatted documents linked on this page, you'll need the Adobe ® Acrobat ® Reader. Download a free reader now.