Duluth, Minnesota is taking another run at finding someone to rehabilitate its most famous structure. The city has posted a rebid for rehabilitation of the Aerial Lift Bridge after its first attempt to hire a contractor did not result in an award.
The bridge, which spans the Duluth Ship Canal at the edge of Lake Superior, has been lifting and lowering for ships since 1905. It was originally built as an aerial transporter bridge, then converted to its current vertical-lift configuration between 1929 and 1930, making it one of the oldest operating lift bridges in the country. The American Society of Civil Engineers designated it a National Historic Civil Engineering Landmark, and it sits on the National Register of Historic Places.
The bridge is no museum piece. It rises 5,000 to 6,000 times each shipping season to let ore freighters and ocean-going vessels move in and out of the Port of Duluth-Superior, which handles roughly 35 million short tons of cargo annually. It also serves as the only road link for Park Point, the residential sand spit where about 1,000 people live. Any prolonged closure affects both residents and the summer tourism economy that draws hundreds of thousands of visitors to watch the bridge lift.
Source: NationGraph.
What tripped up the first solicitation isn't entirely clear. The rebid does come amid a well-documented shortage of contractors with the mechanical, electrical and structural expertise to work on counterweight-and-cable lift systems. Fewer than 100 vertical lift bridges remain in the United States, and the specialized firms that service them are stretched thin as a wave of long-deferred maintenance projects competes for their attention, many of them spurred by federal infrastructure funding from the 2021 Infrastructure Investment and Jobs Act.
The financial stakes for Duluth are significant. Unlike most bridges of its size, the Aerial Lift Bridge is owned by the city, not the state, meaning Duluth's roughly 86,000 residents and a modest municipal budget bear the full cost of major repairs. As NationGraph previously reported, [the city has been moving to address the bridge's rehabilitation needs](articles/duluth-moving-to-rehabilitate-its-121-year-old-aerial-lift-bridge) for some time.
Whether this second round of bidding draws qualified contractors, and at what price, will determine how quickly work can begin on a structure the city can neither ignore nor easily afford to fix.
