By Larry Scott
I was driving a power company truck when I first encountered the bridge. It was twilight, and all I really saw was a roadway consisting two narrow strips of metal stretched across several hundred feet of uneven railroad ties. On both sides, it was, obviously, a long way down. I stopped and stared, then took a deep breath and eased forward.
It was daylight the next time I approached the bridge, and I happened to look up. While I’d been involved in metal fabrication most of my life, I had never seen anything like it. Instead of H-beams, I was staring at structural members that appeared to be quarter-circle castings, hot-riveted together. There were a lot of strange-looking tension rods, and the corner braces were decorative castings.
Later, I learned the bridge is a lone survivor along the old New Mexico and Arizona Railroad, built in 1882.
The original route extended from the Southern Pacific line in Benson, South to Fairbank and, from there, West to Nogales. Ranchers used it to ship thousands of cattle to market. The mines in the Patagonia area shipped ore to the smelters. The little towns, Mowry, Harshaw, Washington Camp, and Duquesne thrived. Sonoita, Elgin and Patagonia came later.
As time passed, railroad locomotives became heavier - too heavy for the bridges along the way. As a result, full sized locomotives brought trains from Benson to Fairbank, and a smaller switch-engine took the cars on to Patagonia. The smaller, slower railroad soon became known as the Burro Train. During the 1930s, the segment from Patagonia to Nogales was discontinued.
Around 1962, after 80 years of service, the little railroad finally shut down and the rails and ties were taken up. Today, the original road grade is still visible on satellite photos, but little else remains.
However, on the Babocomari Ranch, between Huachuca City and Elgin, portions of the railroad bed still serve as ranch roads. And the bridge across Babocomari Creek is still useable - in a white-knuckle sort of way.
My research identified the bridge as a modular unit designed by Phoenix Bridge Company of Phoenixville, PA. The main structural members are Phoenix Columns, based on an 1862 patent. Each column is a hollow cylinder composed of four or more wrought iron segments, riveted together. The design was lighter and stronger than the cast iron columns of the era.
Soon, the company began standardizing components. Potential customers could look at a Phoenix Bridge Company catalog of standardized assemblies and purchase prefabricated components for their specific needs.
Railroads were their biggest customers, although nearly 300 Phoenix Column highway bridges were built between 1885 and 1895.
Old photos indicate that four fairly typical Phoenix bridges served the little railroad before its demise in the early 1960s. However this one, on private property, appears to be the only remaining bridge of its type in Arizona.