Employing more than ten thousand workers, the Fort Peck Dam slowly took shape in the dusty plains of Eastern Montana. The Army Corps of Engineers would tame the Missouri River with a largely untrained work force, utilizing hydraulic fill to pump water, mud, and shale over seven miles to the dam site. Electric line was built to bring power to the pumps from Great Falls, three hundred miles away. Railroad was built to bring millions of tons of rock and supplies to the dam site. Construction was divided into three parts simultaneously under construction: the dam, the spillway, and the tunnels that connected the two.