DULUTH — Last spring's torrential flooding along the North Shore ravaged two iconic red bridges over the Poplar River belonging to the historic Lutsen Resort.

Now, the resort's owner is under investigation for repair work that began in the river that runs alongside the resort without a necessary permit, said the Minnesota Department of Natural Resources (DNR).

Lutsen owner Bryce Campbell called the matter a misunderstanding.

The DNR said it learned in early September that repair work on the bridges and riverbank was underway. Damage stemmed from flooding in May when a few inches of rain combined with several feet of late-season inland snowmelt to create surging rivers in St. Louis, Lake and Cook counties. The high water closed roads, state parks and trails.

Lutsen had not yet applied for a required public waters work permit when a conservation officer visited the resort Sept. 7, said DNR spokeswoman Gail Nosek. even though crews had completed placement of riverbed rock for erosion control and started work on the bridges.

The agency ordered the resort owner and contractor to cease work until they had the permit. DNR allowed the contractor to operate machinery in the river to reach the lower damaged bridge to complete out-of-water repairs, as the agency determined it was no longer safe to cross. That work was supposed to stop Sept. 15 to protect crucial fish spawning, a season that begins that day and runs through June 30, Nosek wrote in an email.

When a conservation officer returned to the resort Sept. 15, he saw "work that was beyond the scope of what was allowed under the emergency authorization," Nosek said.

Campbell, who also is president of North Shore Resort Co., said his contractor wasn't moving river rock for erosion control. Campbell said he was cleaning up huge quantities of rock and debris that were swept into the mouth of the river during flooding, and had piled up roughly 20 feet of it.

Familiar with erosion projects, Campbell said, they would use a different material for that effort, which will need to cover several hundred feet and require involvement of the property owner across the river. He acknowledged the need for a permit to do bridge repairs from the river, but he said emergency authorization had been granted to go forward.

On the last day work was allowed, Campbell said, his contractor found a loose bridge footing in the riverbed and wanted to pour a new one. The DNR said that was outside the scope of the emergency authorization. Now, Campbell said, they were exploring a permit to do that work or a redesign of the bridge span with a truss system and footings on the sides of the river.

They'll work with the DNR on either plan, he said, to restore the bridge.

"It means a lot to us and to a lot of people," he said.

Because the DNR, the U.S. Army Corps of Engineers and the Cook County Soil and Water Conservation District are still investigating, the DNR wouldn't offer any other information.

Campbell, with his mother and business partner, Sheila Campbell, bought Lutsen Resort in 2018. He also bought Superior Shores Resort in Two Harbors in 2020 for about $15 million.

Dick Nelson's family founded Lutsen Resort in 1885. He said the new owners should have gone through the proper channels before beginning work, "but the river is in better shape now than after the storm, and it wouldn't have fixed itself."

The bridges — one now removed — had been pummeled by piles of old-growth pine and spruce trees and debris, jammed into place as the river swelled into Lake Superior.

"It was an avalanche of junk," said Nelson, a Lutsen resident and avid fisherman. "It was plugged with foreign gravel from culverts and roads. It needed to be dredged out."

The mouth of the Poplar as it empties into the lake is a small, heavily fished space, said Don Schreiner, a fisheries specialist for Minnesota Sea Grant, the University of Minnesota's Great Lakes research program.

It's not a major spawning location because of its size and steep falls upstream, he said, but it does see coastal brook trout and coho, chinook and pink salmon most years. Backhoe tracks and rock and sediment movement could disrupt or destroy their spawning beds, which is why the DNR allows work in the river during only a narrow window of time, Schreiner said.

Because it winds through the Lutsen Mountains area, Poplar River is "watched closely" by state agencies, he said.

Campbell, who also owns the Copper River Inn in Fort Frances, Ontario, said removal of trees and brush had been done during the summer. The upper bridge isn't likely to be replaced. Half of it was salvaged, and Campbell said the material might be preserved by fashioning it into a new gazebo.