The Waddell A-Truss: A Patented Bridge Saved from a Lake

The iron bridge at English Landing Park in Parkville has an unusual biography: it was built in eighteen ninety-eight, served rail traffic for forty years, then carried highway traffic for decades, was disassembled to make way for a reservoir, and finally was erected here as a historic artifact. It was designed by engineer John Alexander Low Waddell under his patent from the early eighteen nineties, a system he developed specifically to give short-span railroad bridges a reliable, cheap, quickly assembled solution. The A-frame shape, with its distinctive diagonal geometry, was the answer.

Built for a creek crossing near Trimble, Missouri, it carried trains until nineteen thirty-nine and cars on Missouri Highway Four until nineteen eighty, when the Smithville Reservoir flooded its original site. When federal engineers documented it that year, only two Waddell A-truss bridges were still standing in the country. It was moved to Parkville in nineteen eighty-seven and listed on the National Register of Historic Places.