Grand Coulee Columbia Rivers pathway and onto the southern plateau creating an ice dam. This dam backed up the waters of the Columbia into Glacial Lake Columbia and later during the Missoula Floods forced those waters into eastern Washington, creating the Scablands. The river at Grand Coulee found no existing valley and thus forged its own pathway across the divide, creating the Upper Coulee. The plateau is not level, but is marked with wrinkles and upfolds of the basalt. The diverted waters of the Columbia, encountered the monoclinal flexure, a steep warping up of toward the northwest. Lake Columbia topped the ridge
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