Grand Coulee on through and beyond Quincy Basin. The Ephrata Fan is a gravel fan formed when floodwaters from the lower Grand Coulee entered the Quincy Basin during the formation of the Scablands. The area surrounding the Grand Coulee is shrub-steppe habitat, with an average annual rainfall of less than . The Lower Grand Coulee contains Park, Blue, Alkali, Lenore, and Soap lakes. Until recently, the Upper Coulee was dry. The Columbia Basin Project changed this in 1952, using the ancient river bed as an irrigation distribution network. The Upper Grand Coulee was dammed and turned into Banks Lake. The lake is
Grand Coulee Dam Frank A. Banks served as the chief construction engineer. Bert A. Hall was the chief inspector who would accept the dam from the contractors. Orin G. Patch served as the chief of concrete. Construction conditions were dangerous and 77 workers died. To prepare for construction, housing for workers was needed along with four bridges downstream of the dam site, one of which, the Grand Coulee Bridge, exists today. The Bureau of Reclamation provided housing and located their administrative building at Engineer's Town, which was directly downstream of the construction site on the west side of the river. Opposite Engineer's Town,