BPA, NorthWestern Energy, approaching milestone on Montana to Washington transmission upgrade

The Bonneville Power Administration (BPA) and NorthWestern Energy (NYSE:NWE) are approaching a milestone in the proposed Montana-to-Washington transmission system upgrade.

BPA has completed the last of five public meetings and is accepting final public comments through July 2, after while it will begin the environmental impact statement (EIS) process for its portion of the project.

The two-phase project will upgrade the transmission system from Colstrip, Mont., to Washington state to facilitate the transfer of renewable energy from eastern Montana.

The project was announced by NWE and three other ownership partners nearly four years ago, in September 2008, and both sides have been studying and coordinating since then. “We can’t upgrade independently of BPA,” an NWE spokesperson told TransmissionHub on June 25. “Without their upgrade, our wind energy would have nowhere to go.”

BPA confirmed the need to upgrade its portion of the system during transmission studies conducted in connection with its 2010 network open season process. Those studies confirmed that there was not enough available transmission capacity to accommodate all requests for long-term service from BPA’s Garrison substation in western Montana to load centers west of the Cascades and to market hubs serving the entire Northwest power market, according to BPA’s project web site.

NWE and three other ownership partners will upgrade the easternmost portion of the energy infrastructure, from Colstrip, Mont., to Broadview, Mont.

NWE and partners Puget Sound Energy, PacifiCorp, and Portland General Electric (NYSE: POR) will be responsible for upgrading the Colstrip transmission system (CTS), which consists primarily of twin 500-kV lines that carry electricity from the companies’ jointly owned Colstrip power plants in eastern Montana to Broadviw, Mont., where the CTS lines interconnect with the BPA system.

“We are in the process of working with the other owners of those lines that we have an interest in to upgrade our section, but in order for the wind to be carried all the way to where we believe the markets are located, we need for BPA to upgrade their section as well,” the NWE spokesperson said.

BPA’s portion of the project will include reconductoring 12 miles of the 500-kV line Taft-Dworshak line from Broadview west into Washington state to match the capacity of the rest of the line. BPA will also build a new substation between Missoula and St. Regis, and reinforce five substations in Montana, Idaho, and Washington.

Because BPA’s portion of the project will use existing infrastructure, the EIS process will study two alternatives: to pursue the reinforcement of the transmission facilities, or a “no action” alternative in which BPA would continue with current operation and maintenance practices.

Environmental work is expected to be complete in fall 2014, according to BPA’s project fact sheet. A final decision about the proposed transmission system upgrades and new substation will be documented in a record of decision that will follow the final EIS.

Actual construction has not begun on either phase of the project. Neither company is proving a cost estimate at this time.