South Prairie Reservoir and Control Structure

Project Overview

This component of the Northwest Area Water Supply (NAWS) project includes the construction of a flow control building, hydraulic control structure, and site work including access roads, utility piping, generator, mechanical, and other miscellaneous work. The flow control structure’s interior work, includes a bridge crane, structural steel catwalk/stairs, process pipe and valves.

The hydraulic control structure provides a transition from the pressurized pipe south of the continental divide to gravity fed pipe north of the divide. The flow control structure, located 6 miles north of the hydraulic control structure, houses the pipe gallery with pressure sustaining valves to regulate the reservoir’s influent and effluent flows. This system will help provide drinking water from Lake Sakakawea to over 81,000 North Dakota residents.