Milwaukee bridge repair costs up in the air

By Beth Kevit

The city of Milwaukee might have to come up with more than the estimated $15.5 million to fix its shabbiest movable bridge if the state rules the span is historically significant.

The South First Street bridge over the Kinnickinnic River was built in 1958 and is on the National Bridge Inventory’s list of structurally deficient and fracture critical bridges.

Scot Becker, director of the Wisconsin Department of Transportation’s Bureau of Structures, said the bridge is considered structurally deficient because the deck grid is deteriorating, support beams are rusting and piers are cracking. The counterweights that are used to raise the bridge deck, he said, are rusting and showing signs of distress.

The fracture critical designation, Becker said, does not indicate the bridge is in danger of failing. Rather, he said, that description stems from the bridge’s steel girders. If those supports fracture, he said, flaws could spread more easily than through concrete supports.

“It’s just something,” Becker said, “that you’re watching for to repair.”

Craig Liberto, Milwaukee’s structural design manager, said the bridge is scheduled for rehabilitation work in 2016. But he said he expects the state to classify the bridge as a historic structure, an action that could increase the price of repair.

The State Historic Preservation Office has not started to study the bridge’s significance, Liberto said, but the city’s policy is to request historic reviews on spans that are older than 50 years. The preservation office has the authority to conduct the reviews when projects use state or federal money, and Milwaukee, he said, has asked the state to help pay for the rehab.

Jim Draeger, state historic preservation officer, said the preservation office uses criteria established by the National Park Service to determine whether something is historic and generally evaluates a bridge based on its engineering features. A bascule bridge, such as the First Street bridge, uses counterweights to raise at least one end, unlike a vertical lift bridge, which raises the entire deck.

A bascule bridge, Draeger said, or a bridge with steel trusses, would warrant a closer look from the preservation office.

“Just because it’s old,” he said, “doesn’t mean it’s historic.”

Liberto said the cost of rehabilitating the Kilbourn Avenue and State Street bridges in Milwaukee went up after the preservation office deemed them historic. For example, he said, the State Street span’s bridge house, which was built with copper on its exterior, needed to be repaired while maintaining its historical integrity.

“Obviously,” Liberto said, “we’re not going to replace it with aluminum siding.”

Becker said the vertical lift bridges over the Milwaukee River on Michigan and Wells streets also are on the structurally deficient list because of deterioration and on the fracture critical list because their designs include steel girders.

Liberto said the Wells Street bridge rehabilitation is scheduled for 2017 and is expected to cost $3.9 million. The Michigan Street bridge work also is scheduled for 2017 and is expected to cost $10.7 million.

That schedule is laid out in the city’s six-year capital plan, he said, but city leaders could change that timeline if other projects become urgent.

“They’ve been pretty good,” Liberto said, “but sometimes things shift.”

Until the First Street bridge can be rehabilitated, the city will inspect it every year, Liberto said, and keep it patched together and safe for use.

“The city’s been real aggressive trying to maintain our bridges,” he said, “but there’s a long list.”

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