Geology of the Pacific Northwest along their course. The larger cataract was that of the upper Grand Coulee, where the river roared over an waterfall. The eroding power of the water plucked pieces of basalt from the precipice, causing the falls to retreat and self-destruct by cutting through to the Columbia River valley near what is now the Grand Coulee Dam. The other major cataract is now known as Dry Falls. It started near Soap Lake in Washington State, where less resistant basalt layers gave way before the great erosive power of this tremendous torrent and waterfalls developed. As in the upper Grand Coulee, the
Grand River (Michigan) conducted studies and explains resulted as it moves downstream. The expedition offered presentations, displays and demonstrations to communities along the river in an attempt to interact with the river, its tributaries, and its people throughout the watershed. One of its stops was in Portland, at the riverside Verlen Kruger Memorial pavilion. Kruger traveled over by paddle, was the 1990 and 2000 GRE Rivermaster, and counted the Grand as his favorite river. A 500-passenger dinner cruise ship modeled after a riverboat operates on the river in Lansing. Grand Rapids was built on the site of a mile long rapids on the