BNSF Black River Bridge

Located near the former railroad station of Lytles, this large through girder bridge carries the former Chicago, Burlington & Quincy Railroad mainline over the Black River alongside the former Chicago & North Western Railway bridge. The first bridge at this location was constructed in 1886, and consisted of a pin-connected Pratt through truss bridge, fabricated by the Union Bridge Company. The truss spans were set onto stone piers, and it is believed that the bridge was approached by timber pile trestle spans. In the early 20th Century, the CB&Q invested significant capital into double tracking and upgrading this line. A section between La Crosse and Lytle was double tracked in 1910, and a new bridge across the Black River was constructed in 1917. Upon replacement, it is believed that the old truss spans were reused at another location, and it is unknown if they are still standing today. The only major alteration to the bridge came in 2006, when the concrete slab spans were replaced with modern versions of the same design, giving the structure its present configuration.

Currently, the bridge consists of two 93-foot and one 78-foot through plate girder spans, approached by four 40-foot deck plate girder spans. The through girder spans are constructed at a skew. A lengthy north approach is comprised of 62 concrete slab spans, with lengths between 14 and 20 feet, two additional 40-foot deck plate girder spans, and another 20-foot concrete slab span. Due to the length, the north approach is heavily curved. The bridge is set onto concrete and concrete pile substructures, and portions of the original stone were reused in one of the piers. The through girder spans are heavily constructed, with heavy girders, a ballast deck floor composed of parallel I-beams and deep tapered girder ends. The deck girders also use a standard design, with heavy girders covered by a ballast deck. The original concrete slab spans likely used a standard design, and the current slabs use a typical design seen on BNSF bridges. American Bridge Company fabricated the steel spans, while an unknown contractor constructed the stone portion of the pier. All concrete substructures and the slab spans are believed to have been constructed by railroad company forces. Girder spans were popular for railroad use, as they were durable and easy to construct. The style of concrete pile pier seen on this bridge was standard for the CB&Q, as the piles could be precast offsite and easily installed by railroad forces. Since the 2006 rebuild, the bridge has seen no major alterations, and remains heavily used. Overall, the bridge appears to be in fair to good condition, with no significant deterioration noted. The author has ranked this bridge as being locally significant, due to the common design.