Lost in the northeastern Minnesota storm: a lake

DULUTH — A northeastern Minnesota lake drained to its muddy bottom in last week's torrential rain, pushing its water through an already swollen river basin.

Lake County's Sullivan Lake, next to a popular campground about 25 miles north of Two Harbors, nearly emptied after water broke through its small, 124-year-old dam, constructed of wood, stone and dirt.

The disappearance of an entire lake "is crazy," and Lake County is looking into what happens next, said Matt Pollmann, its emergency management director.

The lake was about 45 acres and 7 feet deep at its greatest depth. Its contents added to the deluge filling the Cloquet River, but that only increased its power slightly, said Ketzel Levens, a meteorologist with the National Weather Service in Duluth. At its peak, water flowed at a rate of 6,200 cubic feet per second, and the lake water contributed up to 5% of that flow, she said, making it a "drop in a much larger bucket."

The U.S. Forest Service owns the old logging dam and will work with the Minnesota Department of Natural Resources on whether to rebuild it, or let the body of water return to its natural state as a channel, said Joy VanDrie, with the Superior National Forest. She said that because it was dammed, it was technically a reservoir, not a lake.

Records show the 7-foot-tall dam was built in 1900. Because it is classified as a low hazard dam, it's inspected once a decade, Vandrie said, and was last inspected in 2017. A low-hazard classification means physical, economic and environmental harm is minimal if it fails. Many old wooden logging dams remain across federal forest land.

The Forest Service said the dam failed without risk to downstream property owners.

In a press release, St. Louis and Lake counties said the failure of the dam could have increased flooding in the Brimson and Island Lake areas.

"It's almost like there was an extra surge that came down with that water," said St. Louis County Sheriff Gordon Ramsay in a separate interview. "The one thing it's brought to light is there are a lot of dams on lakes and bodies of water that we should probably be doing a better job of monitoring."

Dave Anderson is a musician who lives on Indian Lake in Brimson, Minn., about 10 miles from Sullivan Lake. The house he's owned for nearly five decades filled with 40 inches of water beginning Wednesday morning, as the Cloquet River emptied into Indian Lake. Others in the area received some damage, but nothing like his property, he said. He wonders if the dam failure made things worse.

"It was coming up about an inch every 10 minutes," Anderson said, maxing out his rain gauge. "I've never seen water rise like that in my life. I was racing to get stuff out of the water."

Neighbors arrived to help him move as many possessions as possible to higher ground, including precious guitars, amps and other musical accessories. But his solid pine floors are a loss, he said, as are his appliances. His garage and other outbuildings filled with water and his septic system backed up into the house.

"Most everything is gone," he said, and now his time is filled with "frustrating phone calls" with his insurance company and others as he seeks help.

Levens said the 5-7 inches of rain that fell in six hours or less beginning June 18 pushed the Cloquet River even higher than it rose during the flooding of 2012.

"It was a pretty major flooding event," she said.