The most unique of the three C&NW Eau Claire Bridges, this deck truss bridge has had a long history. The first bridge was built here in 1871, and was a wooden howe deck truss bridge. Next, a lattice deck truss, extremely similar to the Northwestern Bridge just west of here was constructed in place of the aging wood bridge. This bridge had two lattice deck truss spans of 157'2", and a 80' Deck Plate Girder approach on each side.
In 1898, the aging deck truss bridge was replaced with a modernized version of it. The dimensions remained the same, but the truss type became a double intersection warren deck truss.
In 1901, in the foreshadowing of the large double tracking project, the line between Eau Claire and Altoona was double tracked. This bridge then entered service as a gauntlet bridge, meaning two tracks share one set of tracks. If you look at pictures of the bridge deck prior to ca. 1992, it is very clear that there are two tracks on top.
http://www.rrpicturearchives.net/showPicture.aspx?id=1742831
In 1916, just after the realignment of the tracks, a second bridge was proposed, but never happened due to financial problems.
By 1991, the gauntlet was removed, and the bridge was reduced to a 30 MPH speed limit.
Timeline:
1870-The Western Wisconsin Railway arrives at Eau Claire and builds massive wood truss structures over both the Eau Claire and Chippewa Rivers.
1880/1- both the Chippewa River Bridge and the Eau Claire River Bridge are rebuilt
1898-The Eau Claire River Bridge is completely rebuilt, and new approaches added to the Chippewa River Bridge
1901-The Eau Claire River bridge becomes a gauntlet, line between Yukon Jct and Altoona is double tracked
1911-work begins on a new high speed double track bypass to the single track high bridge over the Chippewa River. Work begins on a new double track bridge about 1000 yards upstream of the current bridge (600 yards above the dam)
August 6th 1912-a new 2.15 mile double track line built with high speed curves and grades opens, allowing trains to travel at a maximum of 60 miles per hour through Eau Claire, until the Eau Claire River Bridge. The new bridge significantly cuts the traffic on the old one.
1914-A double track line between Milwaukee and St. Paul is completed, allowing for high speed passenger and freight travel between the two cities, going through Eau Claire along the way.
1916-Plans for a second bridge parallel to the existing one over the Eau Claire river are brought to life, but are later deemed too expensive
1991-The double track is completely removed
1992-old Chippewa River Bridge abandoned
1995-Chicago & Northwestern is swallowed by Union Pacific
2007-Excel Energy purchases old Chippewa River Bridge from Union Pacific due to demolition plans, donates it to Eau Claire to save their gas line
2013-Old Chippewa River Bridge to become a trail
For anyone who wants to know what Gauntlet track is: http://en.wikipedia.org/wiki/Gauntlet_track