How does Grand Coulee Dam help provide electricity during winter?

The Grand Coulee Dam helps meet increased electricity demand during the winter by augmenting the river's low natural flows. Because the demand for electric power is often highest during the winter, the dam utilizes upstream storage reservoirs in British Columbia, Canada, to manage water availability.1

By leveraging this stored water, the dam can maintain higher levels of hydroelectric power generation when natural river flow would otherwise be insufficient. Additionally, the dam is part of a broader regional network; the Pacific Northwest system is linked to power grids in California and the American Southwest, allowing for the exchange of power to help balance seasonal loads.1