Hydropower generation in the Pacific Northwest continued to trail historical averages in August, when above-average temperatures prevailed.
Average temperatures in much of the Columbia River Basin were 1 degree Fahrenheit to as much as 6 degrees Fahrenheit above normal in August, while precipitation varied across the region, according to the U.S. National Oceanic and Atmospheric Administration.

Data from the U.S. Army Corps of Engineers show that total net generation at 23 hydroelectric plants across the Pacific Northwest in August was 5.0% lower than the year ago level and 11.6% below the 10-year average as it reached 4.57 million MWh. That figure is down 5.3% from July.
Year to date hydropower production through August totaled 45.76 million MWh, down 22.5% versus the year ago level and down 17.0% from the 10-year average for the period.
In the upper Columbia River Basin, the Grand Coulee Dam, the largest of the region, generated 1.68 million MWh, down 4.6% versus the year ago month and down 12.2% versus the 10-year average for the period. The Chief Joseph Dam generated 906,289 MWh, down 4.7% versus August 2018 and down 10.0% versus the 10-year average for the month.
August flows in the lower Columbia River Basin were also lower versus the year-ago period. Located on the Washington-Oregon border, the Bonneville Dam produced 121,234 MWh, down 0.7% versus August 2018 and 24.6% lower versus the 10-year average for the month. The Dalles Dam, 50 miles downstream, produced 299,889 MWh, down 5.8% from the year-ago month and down 12.5% from the 10-year average for August.

