How are Columbia River power plants connected to the Pacific Northwest power network?

The power plants along the Columbia River system are integrated into the Pacific Northwest power network through a series of high-voltage, federally owned transmission lines. These lines serve as the backbone of a regional grid in which all local utilities participate.1

This interconnected system extends beyond the Pacific Northwest, linking with power grids in California and the American Southwest. This arrangement allows for efficient energy management: surplus power generated by the Columbia River plants is sold to the Southwest during the summer, while steam-generated power from the Southwest is transmitted to the Northwest during the winter when demand is at its peak.1