Things To Do. The Lake House Manitowish Waters Just a short walk from The Lodge, The Lake House has an eclectic array of upscale gifts and home goods for Northern Living. Stop in to find the perfect... The Spa at Manitowish Waters Manitowish Waters Discover a full service oasis in the heart of the Northwoods.
The dam is located approximately 4 miles (6 km) northeast of Orofino and impounds the Dworshak Reservoir for flood control and hydroelectricity generation. With a height of 717 feet (219 m), Dworshak is the third tallest dam in the United States and the tallest straight-axis concrete dam in the Western Hemisphere.he reservoir is required to maintain a minimum of 700,000 acre feet (0.86 km 3) of winter flood-storage space, and dam releases are operated so that water levels reach a maximum of 1,570 feet (480 m) in July.
The key trench is incorporated in the design for two reasons: to anchor the dam to the base material and to prevent piping (seepage under the fill). The key trench should be a minimum of three feet deep for a dam the height of 10 to 12 feet. It should extend the full length of the dam and reach one third to one half of the way up the side slope of the draw. The dam must be constructed from an impervious (clay or clay-based) material.