Columbia Basin Project were built at the north and south ends of Grand Coulee, the dry canyon south of Grand Coulee Dam, allowing the coulee to be filled with water pumped up from the Columbia River. The resulting reservoir, called Banks Lake, is about long. Banks Lake serves as the CBP's initial storage reservoir. Additional canals, siphons, and reservoirs were built south of Bank Lake, reaching over . Water is lifted from Lake Roosevelt to feed the massive network. The total amount of the Columbia flow that is diverted into the CBP at Grand Coulee varies a little from year to year, and
Grand Coulee, Washington 100 females age 18 and over, there were 80.5 males. The median income for a household in the city was $21,818, and the median income for a family was $29,375. Males had a median income of $25,625 versus $18,125 for females. The per capita income for the city was $13,639. About 11.7% of families and 19.3% of the population were below the poverty line, including 25.3% of those under age 18 and 17.6% of those age 65 or over. Grand Coulee, Washington Grand Coulee is a city in Grant County, Washington, United States. The population was 988 at the 2010