The Kinzie Street Bridge is more than just a river crossing; it’s a landmark steeped in history and engineering significance on the Chicago River. Located in downtown Chicago, this bridge, along with the adjacent Carroll Avenue Railroad Bridge, tells a compelling story of the city’s growth and its relationship with its iconic river.
There are actually two bridges at this Kinzie Street location. The first is the Kinzie Street Bridge itself, a crucial part of Chicago’s Department of Transportation (CDOT) infrastructure. Right next to it, you’ll find the raised Carroll Avenue Railroad Bridge, an active railway bridge managed by Union Pacific Railroad.
The Kinzie Street Bridge: From First to Last
The Kinzie Street Bridge boasts an impressive historical timeline. Remarkably, the original Kinzie Street crossing holds the distinction of being the very first bridge to span the Chicago River, dating back to 1832. Fast forward through history, and this location also marks a more recent milestone: the Kinzie Street Bridge was the last movable bridge on the Chicago River to be staffed with a full-time bridge operator, ending this era in 1999.
The current Kinzie Street Bridge, inaugurated on May 10, 1909, signaled the end of the swing bridge era in Chicago. Its design is noteworthy for several reasons. It’s a single-leaf bascule bridge, a less common design compared to the double-leaf bridges prevalent elsewhere on the river. Furthermore, for those interested in bridge engineering, it’s considered the most easily accessible example of a first-generation Chicago-type bascule bridge in the downtown area.
First Generation Chicago-Type Bascule Bridge
What exactly defines a first-generation Chicago-type bascule bridge? The key characteristic is its “hump-backed through truss” design. This structural element accommodates the rack and pinion gearing system, which is positioned outside the truss. Later generations of Chicago-type bascule bridges evolved to feature internal gearing setups. This advancement allowed for different types of supporting truss systems, which you can observe in many of the Loop bridges in Chicago. The Kinzie Street Bridge, therefore, represents an important early stage in the development of Chicago’s iconic movable bridge technology.
Kinzie Street Bridge and the Great Chicago Flood of 1992
The Kinzie Street Bridge is also indirectly linked to one of Chicago’s most unusual disasters: the Great Chicago Flood of 1992. To understand this connection, we need to delve into the history of Chicago’s freight tunnel system.
Dating back to 1898, these tunnels were initially conceived as conduits for a new telephone system. However, they evolved into extensive underground passages, approximately 40 feet beneath street level, measuring a substantial 7.5 feet high and 6.75 feet wide. Large enough for a narrow-gauge railway, the tunnels were intended to streamline freight deliveries to businesses, bypassing the congested surface streets. They facilitated the efficient transport of non-liquid goods, coal for heating, and ash removal to and from commercial buildings.
While the telephone venture faltered by 1916, the freight tunnel system thrived, serving sixty commercial buildings by 1924. Operations eventually ceased in 1959. In the 1970s, the City of Chicago began repurposing sections of the tunnel system for electrical and telecommunication conduits.
Bridges along the Chicago River are typically protected from vessel collisions by groups of pilings near their abutments. In September 1991, these protective pilings were replaced at the Kinzie Street Bridge. Unbeknownst to those involved, the new pilings were driven in slightly different locations than the originals. This seemingly minor change inadvertently compromised the interface between the soil and the freight tunnel directly beneath the bridge. The subtle damage triggered a slow but persistent leak, leading to the erosion of tunnel material over time.
In January 1992, while surveying the tunnels for cable line extensions, cable TV employees discovered alarming levels of silt and water seeping through crumbling tunnel walls. Unfortunately, initial attempts to promptly notify city officials were unsuccessful. The critical report on the tunnel’s deteriorating condition finally reached the appropriate authorities in late February. Regrettably, further bureaucratic delays in recognizing the severity of the problem and implementing a solution ultimately contributed to the tunnel’s failure and the subsequent flood.
On April 13, 1992, a section of the abandoned freight tunnel directly under the Kinzie Street Bridge gave way. Water began surging into the sub-basement of the Merchandise Mart around 6 AM. Within an hour, the floodwaters had reached City Hall and Marshall Field’s (now Macy’s). By 10 AM, Commonwealth Edison initiated power shutdowns across the Loop, and evacuations commenced. The Kinzie Street Bridge, while not directly at fault, became a focal point of this unprecedented event due to the tunnel collapse beneath it.
The Army Corps of Engineers eventually sealed and dewatered the tunnels, returning control to the city on May 22, 1992. The Great Chicago Flood served as a stark reminder of the interconnectedness of the city’s infrastructure and the importance of proactive maintenance and communication.
Raising the Kinzie Street Bridge and Ending an Era
The Kinzie Street Bridge was known for having one of the lowest vertical clearances among CDOT’s movable bridges on the Chicago River. With a clearance of only about 12 feet, it frequently needed to be raised for tour boats and barges to pass. This necessity meant the bridge required 24/7 staffing to operate for navigational purposes, resulting in approximately 5,000 bridge lifts per year.
Recognizing the need for modernization and efficiency, when the Kinzie Street Bridge was slated for a major rebuild in the late 1990s, Chicago engineers decided to increase the bridge’s clearance by five feet. This seemingly small change had a significant impact. The increased clearance eliminated the need for constant staffing, making the Kinzie Street Bridge the last Chicago River bridge to discontinue the practice of having a full-time bridge operator.
The bridge reconstruction process mirrored the approach used at the Wells Street Bridge in 2013. The new bridge leaf was constructed off-site, approximately a quarter mile north of the Kinzie Street crossing. When installation day arrived, the new leaf was transported by barge, floated into position, raised, and bolted into place – a process that took about three days. The rebuilt and modernized Kinzie Street Bridge reopened in 1999, marking both an engineering upgrade and the end of an era for bridge operators on the Chicago River.
An Unfortunate Tour Boat Incident
In a lighter, albeit unfortunate, anecdote from the Kinzie Street Bridge’s history, an incident occurred on August 8, 2004. A group of tourists on an architecture river cruise experienced an unexpected and unpleasant surprise while passing under the bridge. Unbeknownst to them, a tour bus was crossing the bridge overhead and, at the same time, was emptying its sewage tanks. The open steel grate bridge deck offered little barrier, and the unfortunate tourists were doused with sewage.
The tour bus, it turned out, was chartered by the Dave Matthews Band. Taking responsibility for the incident, the band made amends by donating $50,000 each to Friends of the Chicago River and the Chicago Park District. Additionally, they settled a civil lawsuit related to the incident for $250,000. This bizarre event has become a somewhat infamous, if darkly humorous, footnote in the bridge’s history.
Carroll Avenue Railroad Bridge: An Overhead Counterweight Design
Adjacent to the Kinzie Street Bridge stands the Carroll Avenue Railroad Bridge. Designed by the renowned engineer Joseph Strauss, who also designed the Golden Gate Bridge, this bridge opened in 1908. It is unique among downtown Chicago bridges as the only one featuring an overhead counterweight system.
Originally, the railroad line extended to Navy Pier. Over time, portions of the right-of-way were sold or abandoned. The final customer for this rail service was the Chicago Sun-Times newspaper. Newsprint was transported by rail to the Sun-Times printing plant, which was located on the site now occupied by the Trump Tower. This rail operation ceased when the printing plant moved out of downtown in 2001.
Although the rail line is currently inactive, Union Pacific Railroad maintains ownership of the right-of-way across the river. To preserve this right-of-way, the bridge is lowered once a year, and a Hi-rail truck is driven across it. Typically, the Carroll Avenue Railroad Bridge remains in the raised position due to its minimal clearance for river traffic when lowered.
For those seeking more in-depth information, Historicbridges.org offers detailed resources on both the Kinzie Street Bridge and the Carroll Avenue Railroad Bridge.
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Sources:
Bruce Moffat, The Chicago Freight Tunnels; MAS Context, Network – Issue 9 Spring 11; pp72-83
Jon Wren, The Great Chicago Flood, Structure Magazine; August 2007; pp35-40
“Bungling, buck-passing lead to disaster”; April 23, 1992; Chicago Tribune
“City regains control of tunnel”; May 22, 1992; Chicago Tribune
“New era dawns over Chicago River renovations to help curb ups, downs of its many bridges”; October 28, 1998; Chicago Tribune
Case Study: Bridging the Gap; Risi Stone Systems, 2006
Bus waste scuttles boat tour; August 9, 2004; Chicago tribune
Patrick McBriarty, Chicago River Bridges, University of Illinois Press, 2013, p 219
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