From the information sign:
Historic Swing Bridge
The 135th Street bridge is the only remaining example
of this type of bridge in the state of Illinois.
Built in 1899 to cross the Chicago Sanitary and Ship
Canal, it was uniquely designed to allow passage of
large vessels along the waterway.
This two span bridge was able to pivot on a steel
turntable supported by a masonry pier; thus the name
"swing bridge" as it swung across the water to the
opposite bank. The longer east span was the part that
actually crossed the canal, and the shorter west span
functioned as the counterweight arm.
The trusses, which are the supporting framework, were
consructed out of steel and extended up and over the
bridge. Located within the trusses is a overhead
pilothouse where the movement of the bridge was
controlled.
The bridge was a busy, active bridge until its removal
and relocation. After its closing in 1990 due to
structural problems, it was moved to Centennial Trail
for preservation.
Let's Take a Closer Look
Total length of bridge - 302 feet
East span - 204 feet
West span - 98 feet
Total width of bridge - 18 feet
Road width - 18 feet
Walkway width - 5 feet
Height from bridge deck to highest point of truss - 40 feet
Statistics for 1989-1990
Number of closings for canal traffic - 4598
Average closing per day - 7.7
Average closing duration - 15 minutes
Average vehicle crossings per day - 9000
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