Cascade Renewable Transmission, LLC, submitted an application for site certification with EFSEC on October 6, 2025, for a proposed 400-kilovolt (kV) high-voltage direct current (HVDC) electric transmission facility with a capacity of approximately 1,100 megawatts (MW). The line would extend about 100 miles in total, connecting the Bonneville Power Administration (BPA) Big Eddy substation near The Dalles, Oregon, with the Portland General Electric (PGE) Harborton substation in Portland, Oregon.
The transmission corridor would be constructed primarily within the bed of the Columbia River in both Oregon and Washington, including roughly 40 route miles in Washington and 58 route miles in Oregon. To avoid the Bonneville Locks and Dam, the line would exit and re-enter the river in Washington, where about 7.6 miles of overland buried cable would be installed within existing road rights-of-way in Skamania County.
