US Army Corps of Engineers
St. Paul District

Projects

Lac qui Parle Dam

Published Sept. 25, 2017
Updated: Sept. 19, 2019
Description

Lac qui Parle Dam is located on the upper Minnesota River 30 miles east of the South Dakota border. The dam is about 7 river miles upstream of Montevideo and 300 river miles upstream of Minneapolis. The dam was authorized by the Flood Control Act of 1936 (Public Law 74‒738), and construction was initiated by the state of Minnesota as a Work Progress Administration project. Operation of the project was transferred from the state of Minnesota to the U.S. Army Corps of Engineers in 1950. The original authorized purposes were water conservation and flood control, but it is currently operated to include recreation, fish and wildlife, as well as water supply.

The dam is part of the Lac qui Parle project that includes Marsh Lake Dam, Watson Sag Weir and the Chippewa River Diversion. Highway 75 Dam (Big Stone Lake) is located 40 miles upstream of the Lac qui Parle Dam.

Current work at the Lac Qui Parle dam is the installation of a permanent dewatering system and replacement of nine sluice gates and associated operating gear. The dewatering system will also allow for future maintenance on the sluice gate systems without the need for construction of temporary earthen cofferdams. The project was in construction in fall 2016 when consistent high flows led to abandonment of the earthen cofferdam and caused scour at the Minnesota abutment and spillway apron. The project required emergency repairs to stabilize the dam, which were completed in spring 2017.

Purpose

This equipment refurbishment project replaces nine sluice gates and associated operating equipment and installs a permanent dewatering system. Dewatering the upstream and downstream sides of the concrete control structure during construction will be accomplished with temporary earthen cofferdams. The permanent dewatering system, consisting of stop logs installed up and down stream of the sluice gates provides a dry environment necessary for sluice gate and concrete inspections, maintenance, routine and emergency repairs and upgrades.

Status

Plans and specifications for the gate replacement and a dewatering system were completed in summer 2019.  Construction contract was planned for award in September 2019; however, bids received in early September are in excess of 89 percent greater than the Independent Government Estimate (IGE). Working with the Architecture and Engineering firm to evaluate IGE and award in September 2019 if possible. 

Authority

The dam is part of the Lac qui Parle Project authorized by the Flood Control Act of 1936.

Fiscal

Estimated design                                           $600,000
Estimated construction contract              $5,500,000
Estimated total project cost                      $6,100,000