To solve the river navigation problem, the Henry Lock & Dam was built, opening in 1870. The lock and dam project cost $400,000. It was the first lock and dam structure on the Illinois River. While the lock and dam was successful, it raised the water level of the river high enough that it could no longer be forded. As a result, a new wood and iron bridge with a swing span was built between 1867 and 1870. It was designed for horse and carriage traffic.
The Henry Lock was last used in 1927. The 9 foot navigation channel project was underway and the Henry lock was now obsolete. In early 1930s, a barge struck the bridge, damaging it beyond repair. A ferry boat was brought in to provide a river crossing until a new bridge could be built. The new bridge was dedicated on August 15, 1935. It is a steel bridge that consists of six Pennsylvania-style through truss spans. Five of the spans are the same size, while the main river span is slightly larger. The bridge cost $500,000.
The new Henry Bridge was in service until 1988. The deck had deteriorated to the point where it was no longer safe. The deck system, under deck braces, and a number of rivets were replaced. The structure was then sandblasted and painted. Due to the need for the bridge to connect people and services on each side of the bridge, the repair work was performed on shifts around the clock, with the project being completed 6 months ahead of schedule. The bridge emerged in like-new condition, and it serves traffic to this day with only routine inspections and maintenance.
The City of Henry and the bridge are named after James D. Henry, who rose to the rank of General in the army during the Blackhawk war in 1831 and 1832. Henry became ill during the war, and died in 1834 in New Orleans, where he traveled to seek treatment.
