Click the photo to view the full-size version
| Name | CPKC Root River Bridge Chicago, Milwaukee & St. Paul Railway Bridge #K-702 |
| Built By | Chicago, Milwaukee & St. Paul Railway |
| Currently Owned By | Canadian Pacific Kansas City Limited |
| Superstructure Contractor | Unknown |
| Length | 270 Feet Total, 126 Foot Main Spans |
| Width | 1 Track |
| Height Above Ground | 15 Feet (Estimated) |
| Superstructure Design | Pratt pony truss and steel stringer |
| Substructure Design | Concrete |
| Date Built | c. 1901, rebuilt c. 1995 |
| Traffic Count | 15 Trains/Day (Estimated) |
| Current Status | In Use |
| Chicago, Milwaukee & St. Paul Railway Bridge Number | K-702 |
| Significance | Moderate Significance |
| Documentation Date | 11/23/2013 |
In 1871, the Chicago, Dubuque and Minnesota Railway (CD&M) began construction of the line from River Junction, Minnesota to Dubuque, Iowa. At the same time, the Chicago, Clinton and Dubuque Railroad (CC&D) built from Dubuque to Sabula Junction, Iowa. The CC&D portion of the route was sold to Clinton and Dubuque Railroad (C&D) in 1877. Both the CD&M and C&D became part of the Chicago, Clinton, Dubuque and Minnesota Railroad (CCD&M) in 1878. By 1880, the CCD&M was deeded to the Chicago, Milwaukee & St. Paul Railway (Milwaukee Road). Much of this line was located directly alongside the Mississippi River. In the late 19th Century, the Milwaukee Road had developed a large railroad network throughout the Midwest. This route served as a principal line for the Milwaukee Road, connecting several mainlines. This line also allowed for the construction of branch lines further west into Iowa.
The Milwaukee Road was often in financial trouble, especially after the costly Pacific Extension was completed in 1909. In 1925, the company declared bankruptcy, and reorganized as the Chicago, Milwaukee, St. Paul and Pacific Railroad in 1928. Financial hardship continued through the 20th Century for the Milwaukee Road, and the railroad again filed bankruptcy in 1977. By 1985, a suitor for the Milwaukee Road was being sought, and the Soo Line Railroad, controlled by Canadian Pacific Railway (CP) purchased the Milwaukee Road in 1986. In 1997, CP would sell this line to I&M Rail Link, which was purchased by the Dakota, Minnesota & Eastern Railroad (DM&E) subsidiary Iowa, Chicago & Eastern Railroad (IC&E) in 2002. The DM&E/IC&E were purchased by Canadian Pacific in 2008. CP merged with Kansas City Southern Railway in 2023 to form CPKC, the current owner of the line. Today, CPKC operates this line as the Marquette Subdivision. Under CPKC, traffic over this route is expected to increase, and the line has become a backbone of the CPKC system.
Located south of La Crescent, this pony truss bridge crosses the Root River alongside Minnesota Highway 26. Built in approximately 1901, the bridge features a pair of 126-foot, pin connected 6-panel Pratt pony trusses. These spans were a standard design for the Milwaukee Road, and several spans of different sizes were built throughout the system. The bridge originally featured concrete substructures and concrete deck girder span approaches. However, these were filled in approximately 1995, and the north approach replaced with a steel stringer.
Pony truss bridges like this were somewhat rare along railroads in the United States. These spans offered the advantage of being able to span medium lengths, but were often limited to less than 150 feet. This style span had horizontal clearance limitations, but did not have vertical clearance limitations like a through truss. Overall, the bridge appears to be in fair to good condition, with no significant deterioration noted. The author has ranked this bridge as being moderately significant, due to the truss design.
Citations
| Build Date | Estimated based on identical spans |
| Railroad History Citation | ICC Valuation Information, Compiled by Richard S. Steele |