DOE’s Bonneville Power Administration (BPA) prepared an EIS that evaluates the potential environmental impacts of a BPA proposal to build a 500-kilovolt (kV) lattice-steel-tower transmission line that would run from a new 500-kV substation near Castle Rock, Washington, to a new 500-kV substation near Troutdale, Oregon.
After completing the EIS, BPA determined that the electrical reliability issue in the corridor could be addressed without building a new transmission line and cancelled the project. BPA considered the size, local impacts and increasing costs of the proposed project, which prompted the decision to take a hard look at all transmission practices and analytics, including a fresh look at load (electrical demand) forecasts, generation changes and market dynamics.
For more information, see BPA project website.