Kim Fundingsland/MDN A pontoon and sun shelters are being used by workers making repairs on the conduit running beneath the Snake Creek embankment that separates Lake Audubon from Lake Sakakawea.

Workers have begun making repairs on a water release tunnel that runs beneath the Snake Creek embankment that separates Lake Audubon from Lake Sakakawea.

“It is the structure that we release water from Lake Audubon into Sakakawea,” said Todd Lindquist, U.S. Army Corps of Engineers, Riverdale. “Our guys are repairing the structure.”

The embankment, which carries four lanes of traffic on U.S. Highway 83 and a railroad line, is not itself being repaired. However, traffic on Highway 83 in the work area will be slowed and diverted to a single lane in the area of construction for the next several days.

“There are cover plates on the northbound lane of Highway 83 above the gates to control the conduit underneath,” explained Lindquist.

Divers are being utilized to make necessary repairs on the conduit between the two bodies of water. The gravity fed tunnel is used each fall to lower the controlled water level in Lake Audubon by two feet prior to freeze-up.

Lake Audubon’s summer operating level is 1,847 feet, winter 1,845 feet. Maintaining a consistent water level in Lake Audubon is necessary to the operation of the McClusky Canal which exits on the east side of Lake Audubon.

This year though the amount of drawdown of Lake Audubon is expected to include an additional four feet of water. The lower water level will allow workers better access to the wingwalls on either side of the structure where water pumped from the Snake Creek Pumping Plant on the Lake Sakakawea side of the embankment enters Lake Audubon. The repairs are considered to be part of routine maintenance.

Additionally, the Corps will be working on replacing the aging Totten Trail east boat ramp. A spokesman for the Corps said access to the double-wide ramp will continue throughout the construction period, although the ramp will be limited to a single lane. New concrete is expected to be poured on the top half of the ramp, one side at a time to allow boaters access. Then, as the water level in Lake Audubon recedes, work will begin on the lower sections of the ramp.

When all the work projects are completed, the Snake Creek Pumping Plant will be used to pump Lake Audubon back to its customary winter level of 1,845 feet. A likely timeline for completion of the projects and re-filling of Lake Audubon is late October.