The photo linked here is dated March 2, 1909. Part of the builders plate is legible. The first line appears to be: "Wfd Mch & Fo... Co." (the portion between the Fo and Co is obscured) for Weatherford Machine and Foundry Company. The next two lines are clear: "BUILDERS 1908" and "WEATHERFORD TEXAS". The last line is largely obscured but it appears to say "MITCHELL & PIGG PAT'D 1..." with a year at the end. Mitchell & Pigg was a well-known builder of suspension bridges in Texas. Most sources cite 1909 as the year of completion.