2002: (Archived Bridge Hunter; Bridge Hunter is broke, no Historic Bridges; Satellite)
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| Joy Taylor posted The BNSF Four Mile Bridge spans the Des Moines River near Ottumwa and Chillicothe in SE Iowa. |
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| JohnMarvigBridges, cropped Located between Ottumwa and Chillicothe, this massive bridge is locally known as the "Four Mile" bridge. The original bridge here dates to the 1860s. However, that bridge was upgraded at least once before this bridge was built. In 1903, the CB&Q double tracked this bridge, building a five span pin connected Pratt Through Truss bridge, approached by seven spans of deck girder on the west, and five spans of deck girder on the east. This iteration of the Four Mile Bridge was one of several spans built by King Bridge Company for this line. Several others, although much smaller spans, were also built during double tracking projects. In 2002, BNSF decided to upgrade the bridge to the current configuration. The five truss spans were replaced with two new riveted Warren Through Truss spans, as well as several beam spans. Unfortunately, this greatly reduced the significance of this bridge. Unaltered, this would have been one of the more significant bridges over the Des Moines River. Today, the deck girder spans still remain, approaching the modern trusses. Several upgrades have been made to the substructures of the bridge since. |
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| JohnMarvigBridges [I wonder why BNSF went back to rivets. Generally, high-strength bolts have been used since the 1970s.] |
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