Dredging work on the the Bismarck side of the Missouri River is scheduled to begin Monday — work designed to prevent ice jam flooding this winter.
Burleigh County engineer Marcus Hall said crews were on site this week doing preparation work near Fox Island.
Hall said the dredging will be done with a backhoe. A ramp had to be constructed to get the machine close to the area.
The 2011 flood deposited a large amount of sand and sediment. The area of concern is on the south side of Fox Island.
Hall said the sediment created an oxbow that restricts water from flowing downstream.
Last winter, some inland flooding on the south side of Bismarck occurred when the river froze over. The river level rose more than 7 feet overnight.
Hall said the dredging will create a 500-foot channel 7 feet deep and will remove about 11,000 cubic yards of material.
He said that is the equivalent of about 750 dump truck loads. The cost of the project is estimated at $250,000 with the State Water Commission paying for 75 percent of the cost and Burleigh County and the city of Bismarck each picking up 12.5 percent of the cost.
Hall said the work is expected to be completed by the end of the month. The sand removed from the oxbow will be dumped on a large, nearby sandbar, he said.
The dredging on the Mandan side of the river will be done at the confluence of the Missouri and Heart rivers near Fort Abraham Lincoln.
Kelly Casteel of the water commission said it’s hoped the work can be done from shore.
The scope of the work will be dredging 11,000 cubic yards to construct a pilot channel across 1,200 feet of a sandbar of about 45 acres, according to U.S. Army Corps of Engineers documents.
Another 2,000 cubic yards of materials will be removed from a shallow area downstream from the confluence.
The sand will be deposited on an existing sandbar.
The estimated cost on the west side of the river is approximately $300,000, with the water commission paying 75 percent and local sources 25 percent.
Prep work has starting on that area and is expected to be completed by Nov. 30.