City seeks funds for Kern Bridge trail

Dec. 13—When the one-of-a-kind 149-year-old Kern Bridge begins its new life as a pedestrian/bike crossing of the Blue Earth River, one thing would be pretty anticlimactic: Walkers and bikers hitting a dead end as soon as they reach Land of Memories Park.

Technically, the federally funded preservation of the once-doomed bridge doesn't require it to actually lead somewhere when it is reassembled between Sibley and Land of Memories parks in 2025.

"But I don't think we'd be received very well from the public and our users," Assistant City Engineer Michael McCarty said.

Attempting to avoid rebuilding a historic bridge to nowhere, McCarty and other Mankato officials are working to get a missing trail segment constructed and another connecting trail spiffed up before 2025.

If all goes well, the ribbon-cutting ceremony for the Kern Bridge in fall of 2025 will create a continuous trail from the city of Faribault and Sakatah State Park to Mankato and Minneopa State Park.

The missing link is from where the western terminus of the Kern Bridge will be located on the eastern edge of Land of Memories to where Blue Earth County's Minneopa Trail passes the south side of the park — more than a half-mile gap. With the trail connection expected to cost just over $310,000, the City Council has authorized an application for an Active Transportation Infrastructure Grant through the Minnesota Department of Transportation.

The program, created to improve walking and biking conditions in Minnesota communities, is accepting applications through the end of the month for grants ranging from $50,000 to $500,000. A total of $3.5 million in grants is expected to be awarded in late March.

If successful, the trail would be constructed in 2024 — the same year that construction of piers would begin on each side of the Blue Earth River to support the wrought-iron bridge that was dismantled and put into storage in early 2020. The 189-foot bridge had spanned the Le Sueur River southwest of Mankato since 1873 but had been neglected for decades after the closure of the township road it served.

The bridge's stone piers were crumbling and it was in danger of collapsing into the Le Sueur River when Mankato-based MnDOT officials were able to secure federal funds targeted at historic bridge preservation. With Blue Earth County's Public Works Department coordinating the logistics, the bridge was lifted off its piers with a crane and set on the riverbank, where it was taken apart and put in storage containers.

The wrought-iron bowstring arch bridge — the last of its kind in Minnesota and the longest of its type remaining in America — is made up of hundreds of individual pieces assembled with pins. Detailed records were kept for reassembling the intricate structure, and communities in need of a bike or pedestrian bridge were invited to compete to become the next home for the Kern Bridge.

Several did, with Mankato winning the competition in January 2021. Most of the cost of the bridge project — now estimated at $4.51 million — will be covered with the federal preservation funds. Since then, Mankato has hired a consulting engineering firm, selected a precise site for the crossing and overseen an archaeological investigation of the area.

"We have an alignment and we're currently working on our cultural resources," McCarty said.

Designs for the bridge approaches, totaling 550 feet and leading to where the historic bridge will be placed, are being refined to make sure they're reflective of the history and culture of the parks and the confluence of the two rivers. As for the location of the crossing, people can now see for themselves.

"We do have signs so people can better visualize it," he said.

The trail work already has been awarded funding through a federal Transportation Alternatives grant, which means 80% of the trail will be federally funded. The grant application is part of the ongoing effort to identify pots of funding to meet the requirement that the federal funding be accompanied by a 20% non-federal match.

"This helps us fill in that 20%," McCarty said.

The plan is to align the trail along the eastern side of Land of Memories where campsites were once located and then tie into Amos Owen Lane near the park's entrance. The Minneopa Trail passes the park near the junction of Amos Owen Lane and Highway 60/169.

Work on piers for the Kern Bridge is likely to start in fall of 2024, although that will depend on river levels being at typical late-fall low flows.

"The Blue Earth River will dictate when we get to do that work," McCarty said.

Federally funded projects often carry regulatory hurdles that make for longer time lags before construction can begin, even more so when historic structures are involved. So city officials are also trying to prepare for the possibility that steep inflation in the construction sector could push prices up by 2024 and 2025.

"Generally we have been seeing an 8-12% increase in construction costs year over year for many of the items that will be included in the construction of the bridge," McCarty said.

City officials are also pursuing a second trail project that isn't directly tied to the Kern Bridge but is part of the broader connecting trail system that will tie the Sakatah Singing Hills State Trail to Sibley Park and the Blue Earth River crossing via Mankato's Minnesota River Trail.

An application is being submitted to the Transportation Alternatives grant program to cover part of the cost of $1.38 million in needed repairs to the Minnesota River Trail from Main Street to the North Star Bridge. Grant recipients are expected to be announced in April.