Patrick Springer, Published December 01 2010
Sheyenne Diversion project approvedCass County water officials have approved a $1.6 million project to armor the Sheyenne Diversion to handle sustained flows.
The project, slated for summer, will line segments of the West Fargo reach of the diversion with rip-rap rocks to protect against erosion.
Water officials also are looking at raising a control structure called a weir, which is similar to a dam, to keep the diversion dry during times of lower flows.
“So there’s lots of work contemplated on the diversion,” Mark Brodshaug, a manager of the Southeast Cass Water Resource District, said Tuesday.
Because of a prolonged wet period, which began in 1993, the flood-control diversion of the Sheyenne River has seen much heavier use than it was designed to handle. The diversion was completed in 1992.
The diversion’s heavy usage has caused erosion problems, especially in sections of the channel that curve, because of saturated soils and high water flows.
The problems will be exacerbated by releases from Devils Lake into the Sheyenne River – flows that will increase as officials hope to avoid a catastrophic uncontrolled release downstream.
Because of the increased flows from Devils Lake releases, the North Dakota State Water Commission has agreed to absorb much of the cost of improvements planned for the Sheyenne Diversion, Brodshaug said.
“It was designed to run 20 or 30 days a year,” said Mark Thelen, another manager of the Southeast Cass Water Resource District. “It wasn’t designed to run constantly,” which the Devils Lake flows likely will mean.
The project is comprised of two bids, one for a little more than $1 million and another for almost $670,000, both awarded by the water resource district to Tom’s Backhoe Service Inc. of Brainerd, Minn.
Readers can reach Forum reporter Patrick Springer at (701) 241-5522