The “Scissors Bridge”, Brighton Park, Chicago, Illinois

This Pennsylvania Railroad “Eight-Track” Bridge was built between 1909-1910. The unique structure is made up of four side-by-side Scherzer rolling-lift, single-leaf, double-track bascule spans.

Originally a fixed bridge was built in 1901 with the intent to convert it over to a movable bascule bridge at some point in the future. However, when the time came, it was decided that it would be more cost effective to remove the fixed bridge and replace it with bascule or movable spans.

From 1909 to 1910 bascule truss spans were constructed by the Chicago Bridge and Iron Works. The bridge became an engineering marvel due to its unusual design, featuring spans that could operate independently or as a single unit. It also had distinctive ends which made the bridge look like a giant pair of scissors.

After years of abandonment, the western half of the bridge underwent rehabilitation starting in 2015. The tracks were rebuilt, and the bridge was reopened, ensuring it would remain operational for the foreseeable future.

Unfortunately, the original 1901 deck truss approach spans were removed and replaced with modern plate girders during this project, altering the bridge’s historic structure.

Despite this, the rehabilitation project ensures the bridge’s preservation and prevents potential demolition, allowing it to continue its unique place in Chicago’s engineering history.

The bridge’s “scissors” appearance comes from the machinery ends not being aligned on the same side, making it visually distinct from other movable bridges in the area.

The Scherzer rolling-lift bridge was a significant development in movable bridge technology, employing reinforced concrete counterweights and motors to operate the spans.

The bridge was built for the Chicago Sanitary District and was designed by engineer William Scherzer, whose innovations are celebrated in its engineering.

In 1908, Joseph Strauss of the Strauss Bascule and Concrete Bridge Company proposed an alternative design to replace the existing structure with a single-leaf Strauss trunnion bascule bridge. However, this proposal was ultimately rejected in favor of the Scherzer design.

In 2007, the bridge was designated a Chicago Landmark, recognized for its unique design and engineering.

Although no longer movable, it continues to stand as an important piece of Chicago’s infrastructure and history.

From what I understand, this is the lowest fixed bridge at 17 feet on the Lake Michigan to Gulf of Mexico waterway.

GPS Location: 41º50’13.8″N 87º41’15.4″W