Crossing under the freeway viaduct of I-670 are a pair of massive through truss structures, carrying almost all Union Pacific traffic from east to west.
This span is the southern of the two, and is right alongside the Former Missouri Pacific Bridge.
The structure here was originally built in 1903 to replace a single track structure that was destroyed in the flood of 1951. This bridge featured a trio of 180 foot spans.
By 1911, engineers had made the determination that the Union Pacific and Missouri Pacific bridges must be rebuilt with an additional 196 foot span on each end. In addition, a small I-Beam span was added along the backside of the levee at a later date.
Both bridges would be shifted using falsework and a very small margin for error. More about this process can be read Here.
Currently, the structure consists of a trio of 10-panel, pin connected Pratt Through Trusses. These spans were originally constructed in 1903. An 8-panel truss of the same design was added to the west end in 1911; and appears very similar to the 1903 spans. The bridge rests on substructures built in 1911.
The Kansas River has a reputation for flooding quite often. Fortunately for this bridge, it has survived every major flood largely intact. A screw jack lift system was installed after the mega flood of 1951; which destroyed bridges in Topeka.
The bridge remains in an overall good condition, and is heavily used. The bridge has a high level of security, with cameras in every direction. The author accessed this bridge on the east end, by walking inside the levees. Plans are in the works for a trail alongside the west bank of the river, which would make access significantly easier.
The author has ranked this bridge as being moderately significant due to the large span length and great historic integrity.
The photo above is an overview from the east bank. The author hopes to return for better photos in the near future.
| Upstream | Armourdale Rail Bridge |
| Downstream | UP Kansas River Bridge #3 |