Foster Coulee cut off and the Columbia River then discharged through Moses Coulee. Foster Coulee has been studied as a potential pumped-storage hydroelectricity site. The coulee would be dammed and approximately 500 MW generation capacity installed, exploiting the c. difference in elevation between the new reservoir and the existing Banks Lake. Banks Lake is in turn created by pumping water uphill from the Columbia River at the Grand Coulee Dam. The Washington ground squirrel, a candidate for U.S. Endangered Species Act listing, inhabits Foster Coulee. Foster Coulee Foster Coulee is a coulee in Douglas County, Washington. Like the larger Moses Coulee nearby,
Grand Coulee Dam of electricity. Each generator is supplied with water by an individual penstock. The largest of these feed the Third Powerplant and are in diameter and can supply up to . The dam's power facilities originally had an installed capacity of 1,974 MW but expansions and upgrades have increased generation to 6,809 MW installed, 7,079 MW maximum. Grand Coulee Dam generates 21 TWh of electricity annually. This means the dam generates about 2,397 MW of power on average, which results in a total plant factor efficiency of 35%. In 2014, 20.24 TWh of electricity was generated. Grand Coulee Dam's spillway is