SUPERIOR — An unusual sight greeted commuters on the Bong Bridge around 9 a.m. Thursday, Aug. 1.
A large fountain, or geyser, of water bubbled up from the St. Louis River east of Clough Island, reported to be 20 feet tall. The Douglas County Sheriff’s Office responded to the call at 9:09 a.m. Aug. 1, according to a report by Deputy Dana Jensen. wash basin sink drain waste
The culprit wasn’t a northern variant of the Loch Ness Monster, a surfacing whale or hydrothermal vent. It was caused by a hole in an underwater pipe.
Beneath the St. Louis River, between Superior and Duluth, runs a section of a 20-mile pipeline that brings Lake Superior water to the Sappi paper mill in Cloquet.
“If you look on a Google Maps aerial view, you can see how that would be the quickest from point A to B. Rather than going through Minnesota, we actually cross Wisconsin boundaries and then back into Minnesota again,” said Ross Biebl, assistant public works director for the city of Cloquet.
Biebl called the waterline, which has been in service since 1969 and dips under water three times, an “engineering marvel.”
The line begins in Lake Superior with 48-inch-diameter pipes that feed into a pump station on Park Point. The pipes then narrow to 36 inches in diameter to travel under the Superior Bay, through Superior and under the St. Louis River. The water is moved on to a pair of reservoirs in Minnesota and a second pumping station near Spirit Mountain before narrowing to 30-inch-diameter pipes for the final leg of the trip to the paper mill, which includes one more trip under the St. Louis River. The water travels through Duluth, Superior, Proctor, Midway, Thomson and Cloquet.
The water carried by the line is not potable; it’s used in mill processes and then returned to Lake Superior following treatment at the Western Lake Superior Sanitary District. The waterline brings anywhere from 10 to 12 million gallons of water to the paper mill daily, Biebl said.
The problem Aug. 1 was a roughly 8-to-10-inch hole in the top of the underwater pipe. Troubles with the underwater section of the waterline are rare.
“The last time we had an issue with the pipeline underneath the water was 1988 and it was actually in the same location,” Biebl said.
At that time, ice had lifted the structure surrounding the pipe and caused a leak at an air release valve.
“So they put a tapping saddle on it back then and some of the hardware, the bolts, have since rotted away and that’s what caused the issue for us last week,” Biebl said during an Aug. 6 interview.
The pipeline is currently shut down until the spot can be repaired. A diver inspected the site Monday, Aug. 5 to find out what the problem was. No cost estimate was available.
“Now we’re going through the process of trying to find the right repair clamp for the pipe,” using new technology, Biebl said.
The paper mill, which employs approximately 720 people, according to its website, is still able to operate.
“They take water out of the St. Louis River during these types of outages,” Biebl said.
For a city the size of Cloquet, population 12,600, to operate a water pipeline of this size and magnitude is fairly rare, Biebl said.
“It definitely gives the city of Cloquet a lot more to handle and a lot more to deal with. But it’s definitely well worth it for us to be able to supply water to Sappi,” he said.
plastic drains The city is responsible for any repairs on the water line. Cloquet has received $5 million from the state of Minnesota for water infrastructure improvements, Biebl said, and the city is currently in the planning process for how to spend those dollars.