Washington Avenue Bridge

The Washington Avenue Bridge was built from 1901 to 1902 in order to reduce the traffic on the adjacent 1870 Waco Suspension Bridge. The truss has a span of 450 feet, which is an extremely long span length for a simply spanning truss bridge. When it was first built, this bridge was claimed to be the longest known simply spanning truss bridge in the world, although it fell short of that in reality. It was actually the sixteenth longest single-span truss bridge in North America, the tenth longest vehicular single-span truss bridge, and the longest span in the southwest. However, it is now the oldest and longest Pennsylvania Through Truss that is still in the United States.

This bridge is a pin-connected, steel Pennsylvania through truss. The truss has a fairly complex configuration and utilizes built-up beams with extensive lattice and v-lacing. The truss also has decorative portal and knee bracing. This includes star-shaped cutouts on the portal bracing and trefoil and teardrop patterns on the interior braces. The substructure is composed of four 96” diameter piers, one under each of the truss’s inclined end posts. The piers are cast-in-place concrete, with the top twenty feet clad in rolled steel plate. Additional plates and angles are riveted to the piers to provide bracing. In addition to the truss span, the bridge has plate girder approach spans on either end.

The bridge was repaired in 2004 when cracks were found in some of the tension rods. It underwent a major renovation from 2009 to 2010. This project replaced the concrete deck and sidewalk, repaired and replaced the steel bridge members, and installed new crash-tested guiderail. Special care was made to maintain the historical integrity of the bridge, and less than five percent of the original material was replaced. The bridge was also painted black to match its original color.