Pugsley Bridge
Billings engineer Tom Hurdle designed the Pugsley Bridge after powerful ice jams in 1947 and 1949 carried the original 1914 bridge downstream. To avoid future disasters, Liberty County commissioners called for a clear span bridge without piers that could block ice during spring break up. They also set a tight budget of just $53,520. Hurdle responded with an ingenious cable-stayed design that also incorporates suspension bridge features. Standard cable-stayed bridges rely only on cables running directly from the towers to the deck to support loads crossing the bridge. Hurdle’s design follows that plan but also includes concrete deadmen on each bank. Deadmen—huge anchors used on suspension bridges—provide additional support to the towers. When bids from contractors all came in too high, county commissioners hired Hurdle’s brother, Willard, to supervise eight county employees to build the bridge. Completed in July 1950, it cost $51,546, nearly $2,000 under budget. Between 1952 and 1956, heavy trucks crossing the bridge during construction of the nearby Tiber Dam overstressed the cables and caused damage to the camber (arch) of the deck. The deck was eventually replaced with corrugated metal in 1973. In the mid-1980s, the Montana Department of Transportation installed a new timber deck and replaced the original wood guardrails with the existing steel and cable rails. Although Hurdle’s design is beautiful, sturdy, and economical, cable-stayed bridges didn’t gain popularity in the Treasure State. The Pugsley Bridge remains the only cable-stayed bridge in Montana and is likely the only one of this hybrid design in the United States.
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