Flood repairs at Jay Cooke State Park extensive, ongoing

Mark Luschen didn't say if or how he measured the St. Louis River's overflow into Jay Cooke State Park during last June's flood.

He just rounded it off.

It was "a billion of gallons of water," said Luschen, Jay Cooke's assistant park manager. "I'll be dealing with the results of that day for the rest of my career."

As water from torrential rainfall and Forbay Lake's failure cascaded toward the St. Louis River's lower elevation, it dramatically altered the park's landscape and trails, he said.

The rushing water also demolished the park's iconic swinging bridge and the only entrance to the myriad trails and rock climbing opportunities in the park across the river.

Esko's Sue and Adrian Watt were among the first to witness the devastation of the iconic swinging bridge at Jay Cooke during the June 2012 flooding.When they walked across Highway 210 and down near the headquarters of the park on June 20, they couldn't believe their eyes.

"Most of the Swinging Bridge was gone," Sue Watt said at the time. "It was gone."

One of the first two stone pillars that supported the iconic bridge was completely washed away, as well as half of another one. Though several more were still standing, she said the decking was twisted and mangled.

Adrian added that as they stood there, they virtually witnessed the bridge being ripped apart before their very eyes.

"Though the rushing water was a big factor," he said, "I think what took the bridge out more than anything were the trees being washed down the river. They looked like toothpicks being tossed around. From where we were standing, we couldn't see a single rock along the shoreline, and the water was up over the bridge. As the trees got hooked on the bridge, their weight and force really did a number on it."

Work to rebuild the bridge started last month, and is expected to be completed in August or September.

"The project is under some pretty rigid time constraints," Park Manager Gary Hoeft said. "It will for sure be done in time for the fall color season."

Hoeft said design plans are to go back to part of the bridge's original look. He explained that when it was first built by the Civilian Conservation Corps in 1934, the handrails of the ramp leading up to the bridge were made of round wooden logs.

In 1950, the Swinging Bridge was destroyed in what has since become the second largest flood on record (following the 2012 flood). It was recorded at 42,000 cubic feet per second (compared to at 55,000 cubic feet per second in the 2012 flooding). The bridge's smaller pillars were knocked down, the decking destroyed, and one of the main pillars was reported to have toppled. Subsequent reconstruction included replacement of the log ramp with metal railings and chain link fencing.

"Now, we're going backwards in time and using wooden logs once again," Hoeft said, explaining that the stone columns that survived last summer's flood will continue to anchor the bridge.

The state is paying for the project through bonding money but will be reimbursed from federal disaster aid, said Cheri Zeppelin, a Minnesota Department of Natural Resources spokeswoman.

Hoeft said other bridge construction in the park this summer will include replacement of the bridges over Otter and Silver creeks.

Trails in the park

Since last June, Luschen and a mix of labor crews accompanied by the Conservation Corps of Minnesota have attempted to restore the park, repairing more than 40 culverts.

Those efforts, Luschen explained, have led to "85 percent of the park [being] open" for the summer season.

That said, portions of many opened trails are still roped off by orange fencing due to potential risks. As detailed by Luschen and the State Park's map, trails with minor damage and portions of restricted access include Silver Creek, Carlton, and sections of the Ridge Trails.

While many of the trails with minor damage or requiring small, wooden-plank bridges will open by the end of the summer, Luschen also said some of the worst trails -- parts of the Lost Lake, Lower Ogantz, Grand Portage as well as Gill Creek trail -- will require "rerouting or abandonment."

Due to Lost Lake's proximity to the St. Louis River and the fact the Lower Ogantz was built on railroad grade sediment, "a large stretch [of both] disappeared into the river when it flooded," Luschen said. Mudflows also swept away significant portions of the Gill Creek trail along with isolated regions of the Grand Portage trail.

Luschen explained last week that no decisions have been made in repairing those [sections of] trails. Before any action is taken, the park would have to wait for the "stabilization of sediment," which would require an uncertain amount of time, he explained.

"It was a once in 500 year flood," Luschen reiterated.

Concerning the portion of the paved Munger trail that runs through the park, Luschen said the regions damaged by the flood (mainly a section linking Carlton to Thomson) will reopen in late June to early July depending on "hot asphalt mixing," the tendency for construction companies to wait and mix asphalt in bulk. Luschen said repairs to the railroad bridge will be completed during the same timeframe.

Despite Jay Cooke's closure last year and the present's extensive repairs, Luschen said that the park hasn't seen any fluctuation in park-pass or campsite sales thus far in the season, but, he quickly noted, "it's still too soon to" forecast the season. The park's long-term health "is linked to Highway 210," said Mark, which is under repair.

The flood "may force change" to Jay Cooke's trails and features, but, as Luschen said, there is certainly one reason to give thanks: "nobody was hurt."

Highway 210

The flooding closed 26 state highways. Most reopened within days. But Minnesota Highway 210 between Thomson and Duluth's Fond du Lac neighborhood has not.

"Highway 210 is a dilemma," Minnesota Department of Transportation District One Engineer Duane Hill said.

Built on unstable clay soil, large parts of the road washed away or slid down hillsides. To reopen the stretch between Thomson and Jay Cooke State Park's headquarters last year, the state installed a custom-built box culvert at a 35-foot-deep, 100-foot-long washout.

This year, the state will reopen Highway 210 between the park's headquarters and Oldenburg Point, a section where floodwaters tore a 50-foot-deep, 250-foot-wide gap through the road after an earthen embankment gave way on Forbay Lake, part of Minnesota Power's reservoir/power generation system. Work has begun on a $2.9 million project that will build a new bridge over the gap and repair the road.

Part of the highway will be moved farther inland, "so in the future, it is less likely to slide," Hill said.

Last year, MnDOT did emergency work on two sections of the road to give Minnesota Power employees access to the Thomson and Fond du Lac hydro stations. But its future between Oldenburg Point and Fond du Lac is uncertain. In coming months, the state will seek public comment on whether the road should be repaired and reopened, or perhaps converted to a different purpose, such as a multi-use trail. Either way, Hill said, dealing with slides on the clay slopes will remain a long-term issue.

Minnesota Power

The collapse of the Forbay Lake embankment and other flood damage not only washed away part of Highway 210, it took Minnesota's largest hydroelectric generation plant out of service.

Forbay Lake channeled water to the 72-megawatt Thomson generator plant on the St. Louis River. In addition, flooding at the plant damaged its turbines and other equipment. Damages reached an estimated $60 million.

The plant remains out of service until repairs are completed. Federal regulators are reviewing Minnesota Power's plans for rebuilding the forebay. The new design would be better able to withstand flooding like last year's, Minnesota Power spokeswoman Amy Rutledge said. Allete expects to have partial use of the facility by the end of the year and full use by early next year.