Moses Coulee the southern portion of the plateau. These streams had combined into a canyon that drained to the Columbia near the current mouth of Moses Coulee. These side drainages are still visible today along the coulee walls as truncated streambeds, interspersed with gable-like highlands. The Okanogan lobe of the Cordilleran Glacier moved down the Okanogan River valley, covering 500 mi² of the Waterville Plateau and blocked the ancient route of the Columbia River, backing up water to create Glacial Lake Columbia and Lake Spokane. Initially water discharged from Lake Columbia by running up through the head of Grand Coulee and down
Lind Coulee Archaeological Site Lind Coulee Archaeological Site The Lind Coulee Archaeological Site, also known as 45GR97, is the site of an archaeological dig near Warden, Washington. It dates to c. 11,000 cal BP. When it was first discovered in 1947, the site was seen as the first evidence of human habitation of Washington older than about 2,000–4,000 years. It was discovered by the River Basin Surveys program of the Smithsonian Institution. Richard Daugherty (then a graduate student at the University of Washington) was informed of the existence of bones and stone tools about underground, and he began visiting the site in 1948. From