Snake Creek Pumping Plant moves water as needed
Snake Creek Pumping Plant regulates flow
COLEHARBOR – The Snake Creek Pumping Plant is located on the north end of the embankment that separates Lake Sakakawea from Lake Audubon. The embankment is topped by four lanes of U.S. Highway 83, a railroad track and towering highline wires. Underneath, when necessary, flow millions of gallons of water.
Construction on the Snake Creek Pumping Plant began in the fall of 1968 and was completed Dec. 3, 1975. The purpose of the pumping station was to regulate the amount of water in Lake Audubon to ensure a level high enough so that water can flow naturally into the McClusky Canal outlet on the east side of Lake Audubon.
The McClusky Canal provides an irrigation source for farmers as well as water for several small lakes that are popular recreation areas. Those lakes include Brekken-Holmes, East Park, West Park, Hecker’s and New Johns. It is Lake Audubon, which serves as a sort of insurance policy against very dry years, that remains critical to water supply further downstream.
“We keep Audubon at 1,847 feet, basically, so that it can keep a gravity flow through the McClusky Canal,” explained Dustin Offerdahl, Snake Creek Pumping Plant.
Offerdahl oversees operation of the Snake Creek Pumping Plant, often working many feet below the waterline of Lake Sakakawea, where the plant is situated adjacent to the well-known embankment. Three huge tunnels carry water from the plant underneath the embankment to Lake Audubon. The tunnels are 11 feet wide. Seventeen foot tall gates are used to open the tunnels on the Lake Audubon side.
“Anytime I get down to, say 1,846.8, I fire up one of the pumps and pump Audubon back up,” said Offerdahl.
This past summer, said Offerdahl, he ran one pump for 73 hours to bring Lake Audubon up a few inches to the 1,847 level, moving an estimated 2.7 million gallons of water, all which flowed underneath Highway 83.
More recently, the Snake Creek Pumping Plant was called upon for an unusual task, letting water out of Lake Audubon through the facility into Lake Sakakawea. Normally that is done through gravity-fed tunnels not connected to the plant but the U. S. Army Corps of Engineers wanted to avoid possible erosion near the regulating tunnels until further inspection and maintenance can be done next spring or summer.
It was a slow process but Lake Audubon has been dropped to its winter operating level of 1,845 feet. It will remain at that level until shortly after ice out in 2021.
“In the spring, at first ice off, it’s go time,” remarked Offerdahl. “We’ll get the water running as fast as possible and bring that water up. It takes about 10 days to pump Lake Audubon up. It is a substantial-sized lake.”
One of the main reasons for the lowering of Lake Audubon in the fall is to protect rip-rap constructed by the U.S. Fish and Wildlife Service around several of the lake’s islands. The islands are home to nesting waterfowl, shorebirds and the like.
“We get below the rocks so, that way, when the freeze comes, we don’t destroy the rocks,” explained Offerdahl.
Offerdahl spends a lot of time underneath water, so to speak. While the Snake Creek Pumping Plant is highly visible to travelers on U.S. Highway 83, most of the imposing structure lies below the water line. In fact, the elevator in the facility only goes down from the main floor visible from the highway.
“The fourth floor, kind of our discharge floor, is at 1,801,” said Offerdahl while giving a tour of the facility last week. “Right now we’re 38 feet below the level of Lake Sakakawea.”