Grand Coulee Dam of Reclamation was founded, it investigated a scheme for pumping water from the Columbia River to irrigate parts of central Washington. An attempt to raise funds for irrigation failed in 1914, as Washington voters rejected a bond measure. In 1917, William M. Clapp, a lawyer from Ephrata, Washington, proposed the Columbia be dammed immediately below the Grand Coulee. He suggested a concrete dam could flood the plateau, just as nature blocked it with ice centuries ago. Clapp was joined by James O'Sullivan, another lawyer, and by Rufus Woods, publisher of "The Wenatchee World" newspaper in the nearby agricultural centre of
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