Minnesota spends almost $9 million to stop mine pit from flooding Iron Range town

The small Itasca County town of Bovey won a lifeline to stave off flooding this year: State lawmakers approved $8.87 million to drain a mine pit that has long threatened to overflow.

After years of waiting under the threat of a washout, though, officials in the community aren't celebrating yet.

"I don't take it as a matter of fact that it's going to happen until I see it," said Bob Stein, mayor of Bovey.

Water in the Canisteo Mine Pit — really multiple former mine sites that merged as they filled — has been rising 5 to 7 feet each year, according to the Department of Natural Resources. Bovey is directly south of the 5-mile-long body of water and near one of the first spots where water could gush out of the pit.

Groundwater, rain and spring melt are filling up the massive cavity. The DNR temporarily pumped water out of the pit this winter and lowered the water levels below the point where they'd overwhelm existing drainage in the town, but the agency stopped pumping in May.

Now the Legislature-approved money will allow the DNR to install a complicated drainage system that will also prevent the spread of invasive zebra mussels found in the pit, according to Mike Liljegren, an assistant division director for lands and minerals at the DNR.

Liljegren said the presence of the mussels requires special filters — "you can think of it as a bathtub filled with sand," he said — to block juvenile bivalves from riding the drainage out to the Prairie River.

With the new money in this year's infrastructure bill, construction will start either this fall or next spring, Liljegren said.

For years, officials in Bovey were looking for an answer to the mine pit problem as the threat there mounted. Deb Trboyevich, a city councilor and former mayor of Bovey, said water levels in the pit started rising in the 1990s.

Stein first learned the pit could wash out the town in 2006, when he joined the City Council. Five years later, the groundwater flowing away from the pit started seeping up into the basements of some homes in Bovey, and the DNR had to install underground drainage.

"Citizens have moved out of Bovey because they're fearful of what might have happened," Stein said. "We've lost some good taxpayers for our little town."

By 2008, the Western Mesabi Mine Planning Board, which includes Bovey, Itasca County and 12 other nearby communities, had secured a $3.5 million grant to drain the pit, Liljegren said.

But the DNR ended up taking over the project and scuttling the board's design. Liljegren said the Planning Board's design would have been handed off to the DNR for maintenance — and the siphon-based system would have cost between $500,000 and $700,000 a year to operate and maintain, for which the agency didn't have funding.

Stein and Trboyevich both remember the episode as a frustrating one — with the DNR, "it's their way or no way," Trboyevich said.

In 2012, the taconite firm Magnetation started pumping water out of the pit to use in its industrial operations, but it stopped when the company went into bankruptcy in 2016.

Now the new design — a network of pipes, open channels and a box culvert in addition to the sand filters — should fix the problem long-term. It will cost $180,000 a year to run, Liljegren said. State lawmakers did not include that money in their grant to the DNR.

"We'll have to be back at the Legislature next year for [operations and maintenance funding] for this," Liljegren said.

Canisteo is not the only former mine in that part of the state that could unleash flooding. The Hill Annex Mine pit, near Calumet, and the St. James Mine Pit, near Aurora, are also filling with water. State lawmakers approved $2.5 million to design a fix at St. James this year. Any money that is left over from the construction grant for Canisteo can be used to plan for Hill Annex.

All three are legacy mine pits — meaning the mines operated before Minnesota had reclamation rules, so it's the state's responsibility to manage them.

"If [DNR] can get it right this time that would be wonderful," because it won't be the last problematic pit, Trboyevich said.