Grand Coulee Grand Coulee The Grand Coulee is an ancient river bed in the U.S. state of Washington. This National Natural Landmark stretches for about 60 miles (100 km) southwest from Grand Coulee Dam to Soap Lake, being bisected by Dry Falls into the Upper and Lower Grand Coulee. The Grand Coulee is part of the Columbia River Plateau. This area has underlying granite bedrock, formed deep in the Earth's crust 40 to 60 million years ago. The land periodically uplifted and subsided over millions of years giving rise to some small mountains and, eventually, an inland sea. From about 10 to
Coulee City, Washington Coulee City, Washington Coulee City is a town in Grant County, Washington. The population was 562 at the 2010 census. The town was named after nearby Grand Coulee. Coulee City was officially incorporated on May 10, 1907. Coulee City is located at (47.611942, -119.290904). According to the United States Census Bureau, the town has a total area of , all of it land. As of the census of 2010, there were 562 people, 265 households, and 150 families residing in the town. The population density was . There were 331 housing units at an average density of . The racial