The Julien Dubuque Bridge is a continuous steel-arch truss bridge with a suspended deck that traverses the Mississippi River. It joins the cities of Dubuque, Iowa, and East Dubuque, Illinois.
This bridge was named after Julien Dubuque, a French Canadian who arrived near what now is known as Dubuque, Iowa (which is also named after him). Dubuque was one of the first white men to settle in the area. He initially received permission from the Fox Native American tribe to mine the lead in 1788. Subsequently, the Spanish confirmed that transaction by giving him a land grant in 1796. Once he had received permission from the Fox to mine lead, Julien Dubuque remained in the area for the rest of his life. He befriended the local Mesquakie Chief Peosta, for whom the nearby town of Peosta, Iowa, is named.
The Julien Dubuque Bridge is part of the U.S. 20 route, and carries two lanes of traffic and one pedestrian walkway. It is one of two motor vehicle bridges over the Mississippi in the area (the Dubuque-Wisconsin bridge is three miles north and links Dubuque with Wisconsin) and is listed in the National Register of Historic Places.
According to the design specifications, the bridge superstructure was constructed with 1,925 tons of silicon steel and 2,292 tons of carbon steel. The approach spans used 3,205 tons of steel. The substructure required 34,087 cubic yards of concrete, 1,232 tons of steel and 2,909 timber piles. The total cost of construction in was $3,175,341.63.
Its longest span is 845 feet, total length 5,760 feet and width 28 feet. The clearance below the bridge is 64 feet. When built, the 845-foot main span was the second longest over the Mississippi River, fourth longest in the United States and eighth longest in the world.
The Julien Dubuque Bridge replaced an aging structure known locally as the "High Bridge" or "Wagon Bridge." Construction of the bridge was attributed in part to World War II and the need to facilitate military transportation. In 1942, the first parts of the bridge were begun. In 1943, the bridge was completed.
The bridge was originally painted gray to help camouflage the bridge in case of enemy attack. It was later repainted a dark green color and stayed that way until the early 1990's, when it was returned to its historic gray color during a renovation.
Because the bridge was financed with bonds, it was initially operated as a toll bridge. Proceeds were used to help pay off the bonds. In the post-war years, traffic was so heavy that the bonds were paid off 11 years early, and the bridge became toll-free in 1954.
In the early 1990s, the bridge underwent an extensive renovation. The deck was completely replaced, and a new walkway installed on the bridge.
Due to congestion on the bridge, the Iowa DOT has developed preliminary plans to build a parallel, two-lane bridge directly to the south of the Julien Dubuque Bridge. Some federal funding has been secured and right of way has been acquired. Construction is contingent upon additional federal funding being received.