Thousands of pounds of redwood logs stretching along a logger’s pole trailer enter the historic Haupt Creek Bridge in northern Sonoma County, California. Its twelve massive, forty-inch tires roll over riveted wrought iron floor beams. Upset wrought iron diagonal eyebars, pin connected to longitudinal phoenix columns forming the top chord and pin connected to phoenix column verticals, join at bottom chord eyebars where the riveted floor beams are U-bolted to the truss. There is a sound no one hears, internally, its mass of wrought and cast iron less than the enormous weight of the redwood logs, working to resist the heavy weight of the cut redwood logs.
It is working beyond its service life and those who predict the failure of wrought iron, cast iron, and riveted iron. What will destroy this historic bridge and bring it falling into the Haupt Creek below is for one of the forty-inch tires to hit one phoenix column inclined end post.
Haupt Creek Bridge has a confusing documented history; its historic wrought iron has been referred to in official documentation as cast iron or steel. No reliable public record for its date of fabrication, or the fabricators, exists. There are other phoenix column bridges in Northern California, and a search of their records may make a historic connection among them.
