Dry Falls Dam without compaction. Dry Falls Dam Dry Falls Dam is a rockfaced earthfill type dam in the U.S. state of Washington. Located in Grant County near Coulee City, it was built as part of the Bureau of Reclamation's Columbia Basin Project. Water from the Columbia River, impounded by Grand Coulee Dam, is pumped into Grand Coulee, a formerly dry canyon, through the short Feeder Canal. Grand Coulee's north end is sealed by North Dam and Dry Falls Dam stretches across the midsection of the Coulee. This allows the water pumped from the Columbia River to fill the upper Grand Coulee, creating
Grand Coulee pumped from the Grand Coulee Dam, into Banks Lake to act as an Equalizing Reservoir and irrigation water source. Evidence of the waterfalls includes a plunge basin where the falls began, immediately south of Coulee City. It contains at least of gravel lower than the open flooring of the land. The river above the falls was shallow and much wider than the gorge. Thus, it wrapped around the lip of the main falls creating lateral falls. These flowed until the recession of the main falls denied them water. Northrup Canyon in Steamboat Rock State Park, contains a dry cataract as