Moses Coulee course southward past the Frenchman Hills and turning west to run along the north face of the Saddle Mountains and rejoin the previous and modern course of the Columbia River just above the main water gap in the Saddle Mountains, Sentinel Gap. Although the Columbia River flowed only for a short period through Moses Coulee, this period included one or more of the tremendous flows from the Missoula Floods. As the Okanogan lobe melted, the upper portions of Moses Coulee were littered with clear evidence of its passing in the Withrow Moraine. The glacier left behind a blanket of glacial
Grand Coulee, Washington Grand Coulee, Washington Grand Coulee is a city in Grant County, Washington, United States. The population was 988 at the 2010 census. Grand Coulee was officially incorporated on November 6, 1935. It is located above the Grand Coulee Dam and next to North Dam. Grand Coulee is located at (47.939706, -119.001597). According to the United States Census Bureau, the city has a total area of , of which, is land and is water. As of the census of 2010, there were 988 people, 474 households, and 246 families residing in the city. The population density was . There were 554