By Patrick Moes
St. Paul District
ST. PAUL, Minn. — The U.S. Army Corps of Engineers St. Paul District completed construction of the Tolna Coulee Control Structure in Tolna, N.D., May 22, 2012.
North Dakota's Devils Lake started flowing into Stump Lake in 1999, filling Stump Lake and creating one lake with a combined surface area of almost 300 square miles. If Devils Lake continues to rise, it will naturally flow through Tolna Coulee to the Sheyenne River.
The project began a little more than one year ago with the planning phase. The 800-foot wide structure is designed to regulate the amount of water that would flow through the coulee. Completion of this project eliminates the threat of catastrophic flooding along the Sheyenne River if Devils Lake were to exceed 1,458 feet above sea level. According to the National Weather Service, the current lake level is 1,453.24 feet.
"The Tolna Coulee project will prevent catastrophic flows should the lake rise 5 more feet and overflow into the Sheyenne River basin," said Bill Csajko, Corps of Engineers project manager. "Without the project, downstream communities would have had the potential threat of flows twice as large as the greatest historic flows on the Sheyenne River."
The Corps accepted the project from its contractor this week and will turn over the project to the North Dakota State Water Commission for the operation and maintenance in the near future. The Corps is finalizing the operation and maintenance manual and the design documentation report, which includes the as-built drawings and any design changes that may have occurred during the construction process.
A contract was awarded to International Falls, Minn., based Wagner Construction, Inc., for $6.5 million in September 2011. Construction began the following month and continued through the winter. Unique construction techniques were employed to meet the goal of project completion by spring of 2012, including the use of heated tents to allow the concrete to cure during the cold weather.