Omaha Road Bridge Number 15 is a

swing bridge A swing bridge (or swing span bridge) is a movable bridge that has as its primary structural support a vertical locating pin and support ring, usually at or near to its center of gravity, about which the swing span (turning span) can then pi ...

that spans the

Mississippi River The Mississippi River is the second-longest river and chief river of the second-largest drainage system in North America, second only to the Hudson Bay drainage system. From its traditional source of Lake Itasca in northern Minnesota, it fl ...

in St. Paul, Minnesota, United States. It was built in 1915 by the Chicago, St. Paul, Minneapolis and Omaha Railway (Omaha Road), though it, and the line from St. Paul to Mendota, was jointly owned with the Chicago, Milwaukee and St. Paul Railway (Milwaukee Road). The causeway curves around Pickerel Lake in Lilydale, Minnesota, before crossing into St. Paul. The bridge was designed by I.F. Stern of Chicago. It is unusually shaped, because the swing span is asymmetrical. According to local legend, the original bridge design had equal length spans on either side of the center pivot. Once the bridge was completed, the owner of the property on the south side of the river did not want the swing span crossing his land. In response, the owner removed most of the south end of the swing span and added a concrete counterweight to compensate for the lost material. Legends aside, the reason for the "bobtail" configuration of the bridge is that the section of the river deep enough for navigation at that point is not wide enough to accommodate a full-sized swing bridge. The counterweight is necessary to keep both ends of the bridge in balance over the center pier, which is near the right descending bank. While the legend may be an appealing one, it cannot withstand the fact that no qualified bridge engineer would lavish the material and effort required to build a swing span over land. The bridge forces barge traffic heading up river to cross over to their respective port (south) shore of the river, while those heading downstream are able to maintain their normal traffic pattern. An earlier bridge in this location, built in 1869,Stennett, William H.. Yesterday and Today: A History of the Chicago and North Western Railway System. United States: Winship Company, Printers, 1910. was a wooden

Howe truss A Howe truss is a truss bridge consisting of chords, verticals, and diagonals whose vertical members are in tension and whose diagonal members are in compression. The Howe truss was invented by William Howe in 1840, and was widely used as a bridg ...

design. This was one of the original 15 bridges spanning the Mississippi River. The first bridge was an 8-span drawbridge, but much of the superstructure had to be replaced in 1877 because of decay in the original pine chords. It was a joint bridge of the Minnesota Valley Railroad Company (predecessor of the Omaha Road) and the Minnesota Central Railroad Company (predecessor of the Milwaukee Road)

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* {{Crossings navbox , structure = Crossings , place =

, bridge = Omaha Road Bridge Number 15 , bridge signs = , upstream = Lexington Bridge , upstream signs = , downstream = Smith Avenue High Bridge , downstream signs = Bridges completed in 1916 Bridges in Saint Paul, Minnesota Bridges over the Mississippi River Canadian Pacific Railway bridges in the United States Chicago and North Western Railway Chicago, Milwaukee, St. Paul and Pacific Railroad Railroad bridges in Minnesota Swing bridges in the United States Union Pacific Railroad bridges 1916 establishments in Minnesota Chicago, St. Paul, Minneapolis and Omaha Railway

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