Click the photo to view the full-size version
| Name | Plano Railroad Bridge Chicago, Burlington and Quincy Railroad Bridge #50.92 |
| Built By | Chicago, Burlington & Quincy Railroad |
| Currently Owned By | BNSF Railway |
| Superstructure Contractor | Gilbert H. Scribner of Chicago, Illinois |
| Engineer | C.H. Cartlidge |
| Length | 75 Feet Total |
| Width | 2 Tracks |
| Height Above Ground | 40 Feet (Estimated) |
| Superstructure Design | Concrete Encased Steel Arch |
| Substructure Design | Concrete |
| Date Built | 1903 |
| Traffic Count | 20 Trains/Day (Estimated) |
| Current Status | In Use |
| Chicago, Burlington & Quincy Railroad Bridge Number | 50.92 |
| BNSF Railway Bridge Number | 50.92 |
| Significance | Regional Significance |
| Documentation Date | 4/21/2024 |
In 1852 and 1853, the Aurora Branch Railroad of the Chicago,
Burlington & Quincy Railroad would construct a 46 miles of new railroad extending from Aurora, Illinois to Mendota, Illinois. The railroad
would be reorganized as the Chicago and Aurora Railroad Company in
1852, and again as the Chicago, Burlington & Quincy Railroad
(CB&Q) in 1855. Between 1852 and 1854, the Central Military Tract Railroad Company (CMT)
would construct 79 miles from Mendota to Galesburg, Illinois. The CMT would be absorbed into the CB&Q the following year. This route quickly became the principal mainline of the CB&Q, providing a connection to the Mississippi River at Quincy. Both Aurora and Galesburg would quickly become prominent railroad cities, with extensive facilities serving the CB&Q. Because of the heavy traffic served by the line, the railroad would be double tracked beginning in the 1860s. In 1868, a second track was added between Aurora and Bristol, and between Earlville and Mendota. Between Bristol and Earlville, the line would be double tracked in 1872. In 1877, the line was double tracked from Malden to Princeton and near Galeesburg; from Arlington to Malden would be double tracked in 1878; and the segments between Mendota and Arlington and Buda and Wyanet would be double tracked in 1880. The segment between Buda and Galesburg would be double tracked in 1886, and the segment between Princeton and Wyanet was double tracked in 1899. Throughout the 20th Century, the line continued to serve as the principal mainline of the CB&Q. In
1970, the CB&Q was merged with the Northern Pacific
Railway and the Great Northern Railway to form Burlington Northern
Railroad (BN). In 1996, BN merged with Atchison, Topeka & Santa Fe
Railway
to form BNSF Railway. BNSF currently operates the line as the Mendota Subdivision, and it remains a critical line within the BNSF system.
View articles discussing the construction and design of this bridge
Located on the east side of Plano, this unusual concrete arch bridge carries the former Chicago, Burlington & Quincy Railroad mainline over Big Rock Creek. The first bridge at this location was likely a wooden truss bridge, constructed when the line was initially built. In 1862, the bridge would be replaced by a 175-foot timber Howe through truss bridge, set onto stone abutments. In 1881, the bridge would be replaced by a double track iron bridge. This bridge consisted of a 95-foot, 6-panel pin-connected Pratt deck truss span, approached by two 32-foot and a 24-foot deck plate girder span on either end. The bridge would be set onto stone abutments and piers, and the approaches utilized steel bents. Keystone Bridge Company fabricated the superstructure of the bridge. By the early 20th Century, this bridge had become too light for traffic, and would be replaced by the current bridge. Upon replacement of the bridge, the girders were reused elsewhere, and the truss was likely reused in some capacity as well.
Currently, the bridge consists of a 75-foot three center concrete arch span, constructed at a width of 44 feet. Construction was started in August 1903 and completed in March 1904. During construction, it was paramount to maintain traffic over the structure. To maintain traffic over the bridge, the formwork of the arch was constructed with gaps at the truss members. After the arch was constructed, the steel of the old bridge was removed, and the gaps in the arch filled. Finally, the bridge would be filled with gravel. The wing walls of the bridge are constructed around the stone piers of the old bridge, necessary to maintain traffic during construction. These wing walls extend 68 feet, exceptionally long for this early of a concrete arch bridge. Originally, the bridge used some decorative features, such as imprints in the concrete. Concrete arch bridges became popular during the 20th Century as an alternative to steel bridges, but early spans were limited in length. This bridge was among the largest such structures ever constructed when it opened to traffic. In approximately 1975, the bridge was heavily modified, including a full concrete repair of the exterior of the bridge, removing the decorative features. Overall, the bridge appears to be in good condition, despite the modifications. The author has ranked this bridge as being regionally significant, due to the history and design. Despite the alterations, this bridge remains an outstanding early example of a large concrete arch bridge constructed for railroad use.
Citations
| Builder and build date | Engineering News; Volume 52, Issue 25 |
| Railroad History Citation | ICC Valuation Information, Compiled by Richard S. Steele |