US Army Corps of Engineers
St. Paul District


Lac Qui Parle Gate Replacement

Published Sept. 25, 2017
Updated: March 21, 2019

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 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. 

The project was in construction in fall 2016 when consistent high flows led to abandonment of the cofferdam and caused scour at the Minnesota abutment and spillway apron.  The project required emergency repairs to stabilize the dam, which were completed spring 2017.


This equipment refurbishment is intended to replace nine sluice gates and operating equipment.  Dewatering the upstream and downstream sides of the concrete control structure is required to facilitate the gate replacement.  Additional concrete repairs are most effectively accomplished while the dam is dewatered.  A dewatering system would accomplish that requirement as well as provide future gate access for inspections, upgrades and emergency work.


Plans and specifications for the gate replacement and a dewatering system is scheduled for completion in spring 2019 with a construction contract awarded in summer 2019. 


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


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