DULUTH — Twelve years ago this week, this hillside city was hit with a catastrophic flood. On Tuesday, streams and creeks overflowed once again, carving temporary rivers through neighborhoods and flooding tunnels on Interstate 35 as roughly 3 inches of rain fell in just a few hours.

But it appears city efforts fueled by millions in relief aid helped Duluth escape major damage from the unusually heavy rainfall.

Parts of the Iron Range and the North Shore didn't fare as well, with more than 7 inches of rain washing out roads, downing trees and forming walls of waterfalls from rock ledges along Hwy. 61.

"It was the only time I've ever seen that," said Chuck Olsen, a Tofte, Minn., resident who drove through debris and currents of water on Hwy. 61 coming home from Grand Marais. Sporadic, pop-up waterfalls are common in the spring, but the roadside cliffs "were all waterfalls," he said.

Elsewhere, a tree fell on a boy camping in the Boundary Waters Canoe Area Wilderness; a tornado touched down near Cotton, Minn.; and a funnel-like waterspout reportedly formed on Lake Superior. Several northern Minnesota cities, including Hibbing and Ely, saw flash floods and buckled roads.

John Keefover of Duluth lives in an East Hillside neighborhood building near Brewery Creek, which runs partially underground on its way to Lake Superior. He captured on video a massive nearby culvert's powerful overflow, pushing water through the neighboring yard, over the street and down a set of stairs, eventually taking out a section of sidewalk. It's the second time he's seen the culvert swell in 10 months.

"Everything just flows right down to us," he said, noting a foot of water had gathered in his building's basement. "Hopefully the city will take a closer look at this culvert. It's pretty alarming."

State, federal and city money helped replace and, in some cases, improve destroyed culverts, pipes and storm tunnels after the 2012 flood. Some homes built atop underground creeks were bought by the city so they couldn't be used again, and alternative floodwater paths were built.

But Duluth's unusual topography and 60 streams mean vulnerabilities remain, and the city targets those as it can. Inlets to streams that flow underground are checked for clogs, and strong stormwater retention plans on new developments are key, city officials have said.

Mayor Roger Reinert didn't respond to an interview request Wednesday but said in a statement that the measures the city took after the 2012 flood "have served us well."

Dislodged sewer holes, loosened patches of road and saturated trails were among Duluth's minor damage.

On Tuesday, the region 20 miles up the shore from Two Harbors, Minn., had the most rain. Calling it a "rare event," Woody Unruh with the National Weather Service in Duluth said the storm was similar in magnitude to 2012 for some areas.

He said the Weather Service has reports of standing water a foot deep in the inland Arrowhead region, and the swinging bridge at High Falls on the Baptism River in Tettegouche State Park was destroyed, after first being damaged in a 2022 storm. The river has hit major flood stage, and some homes in Finland, Minn., have been flooded, Unruh said.

The Vermilion River at Crane Lake and Kawishiwi River near Ely are expected to crest in the next couple of days.

Major northern Minnesota roads are partially closed from washouts, including Hwy. 1 east of Ely and west of Tower, Hwy. 169 south of Tower and Hwy. 61 at Taconite Harbor. One lane is closed there, with a bypass set up along the heavily used roadway. St. Louis County suffered the most damage in its northern reaches, and officials expect to declare a disaster.

The Superior National Forest saw flash floods and severe thunderstorms that caused damage across the 3 million-acre forest, with assessments underway. Those with reservations for campgrounds or in the BWCAW over the next few days will be contacted by the Forest Service.

Forest officials said washouts have closed the Trout Lake portage, north of Tower, from Lake Vermilion into the BWCAW, and the path will need repair.

And the rain isn't over. The region gets a brief respite before more comes this weekend. The saturated soil means more flooding is expected in low-lying areas.

Grandma's Marathon officials are closely watching the weather ahead of upcoming events. A Facebook post told runners to prepare for wet and cool conditions and to expect more updates later this week. A Grandma's official told the Star Tribune that the current weather hasn't affected the race course out of Two Harbors nor plans to bus runners to their starts of the marathon and half-marathon on Saturday.

Star Tribune Outdoors editor Bob Timmons contributed to this story.

Video (00:35) Flooding runoff from Lester River enters Lake Superior in Duluth on June 19, 2024. Rain amounts ranging from 3 to 7 inches fell in northern Minnesota.