Bonneville Power Administration (BPA) is proposing to upgrade parts of its existing transmission system in Montana, Idaho, and Washington as a result of recent requests for transmission service. BPA is proposing several upgrades on its existing transmission system in order to increase available transmission capacity 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. The proposed upgrades consist of a combination of proposed reinforcements of several existing BPA substations, proposed reconductoring of sections of an existing BPA transmission line, and the proposed addition of a new series compensation substation along other existing BPA transmission lines. To understand the potential environmental impacts of this proposal, BPA will prepare an Environmental Impact Statement (EIS) pursuant to the National Environmental Policy Act.
BPA expects to issue a Final EIS for the proposal in the fall of 2014. BPA’s decision concerning the proposed transmission system upgrades will be documented in a Record of Decision that will follow the Final EIS.