Chasing Chicago’s movable bridges (2014)

In April 2014, a team led by Marcin Wichary extensively documented Chicago’s movable bridges, capturing their operation and historical significance, offering a rare glimpse into the city’s engineering heritage.

The exploration took place over a single day, with participants traveling to multiple bridge sites, including the Ashland Avenue Bridge, Cermak Road Bridge, and the DuSable Bridge. They observed and recorded the operation of various bascule bridges, which use counterweights to lift and lower spans with minimal motor effort. The team also entered some bridges’ control towers, witnessing firsthand the mechanical ballet of opening and closing.

Confirmed facts include the specific bridges visited, their opening times, and the detailed descriptions of their mechanical operation. For example, the Ashland Avenue Bridge was observed at 8:40 a.m., with its counterweighted bascule mechanism clearly visible. The team also documented the historic 1992 incident where the Michigan Avenue Bridge’s repair work caused it to act as a giant catapult, damaging vehicles and debris across Wacker Drive.

Additionally, the team visited the old control booth of the Amtrak rail bridge, observing its slanted structure and lift mechanism, and gained access to the control tower of the State Street Bridge. The exploration highlighted the engineering marvels of these century-old structures, many of which still operate using original or restored mechanisms.

Why It Matters

This exploration underscores the importance of Chicago’s movable bridges as both functional infrastructure and historical landmarks. They exemplify early 20th-century engineering and continue to serve vital roles in transportation. Their preservation and continued operation reflect Chicago’s commitment to maintaining its engineering heritage.

Understanding these bridges’ operation provides insight into urban infrastructure, historical engineering practices, and the city’s maritime and transportation history. The bridges’ mechanical ballet and their stories, like the 1992 accident, contribute to Chicago’s engineering narrative.

Background

Chicago’s movable bridges, primarily bascule types, have been a critical part of the city’s transportation network since the early 1900s. Built to accommodate both road traffic and maritime navigation, these structures exemplify early steel engineering. The 1992 accident at the Michigan Avenue Bridge highlighted the risks involved in maintenance and repair of such aging infrastructure. By 2014, many of these bridges had been operational for over a century, with ongoing efforts to preserve and maintain them amid modern traffic demands.

“Seeing these bridges in action is like watching a mechanical ballet—an elegant, powerful dance of steel and engineering.”

— Marcin Wichary

“The bridges are not just functional—they’re a testament to Chicago’s engineering ingenuity and history.”

— Chicago Architecture Foundation

What Remains Unclear

The current state and operational status of these bridges may have changed since 2014. Details about any recent modernization, restoration, or upgrades are not specified and could impact their current functionality.

What’s Next

Future efforts may include monitoring maintenance and restoration projects, as well as potential public tours or documentation to assess current conditions and operational status of the bridges.

Key Questions

Are all Chicago movable bridges still operational today?

Many of Chicago’s historic movable bridges remain operational, but some may have been replaced or decommissioned. Ongoing maintenance and restoration efforts aim to preserve their functionality.

Can the public visit or tour these bridges today?

Some bridges, especially those operated by the Chicago Architecture Foundation or city programs, may offer tours or viewing opportunities. Access varies depending on the bridge and current safety protocols.

What makes Chicago’s movable bridges unique?

Chicago’s bridges are notable for their age, engineering design, and the fact that many still operate using original mechanisms, representing a significant part of early 20th-century engineering history.

Have there been recent incidents involving these bridges?

While the 1992 Michigan Avenue Bridge accident was a notable historic event, there are no widely reported recent incidents. Maintenance and safety protocols are continually updated to prevent accidents.