Liberty County Bridge Nominated for National Register

Montana Historical Society
  • September 22 2020
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Liberty County’s Pugsley’s Bridge, which is Montana’s only cable-stayed suspension bridge, is nominated for inclusion in the National Register of Historic Places.

The unique bridge across the Marias River has a surprising backstory. A steel truss bridge constructed at the site in 1914 often was damaged by ice during the winter and spring months. A particularly powerful ice jam in March 1947 pushed the original bridge off its foundation and onto the bank. County officials planned to repair the structure, but another ice jam in 1949 pushed it about a mile farther downstream, destroying what was left of the bridge.

Named after area ranchers Leonard and Moses Pugsley, the new Pugsley Bridge was developed specifically for crossing the Marias River at the same location as the old bridge. Engineer Thomas Hurdle decided to use a distinctive system of cables and braces to suspend the bridge decking above the river, removing the need for a pier in the river.

Prior to his engineering career, Hurdle was a bomber pilot who flew 35 missions against Nazi Germany before his discharge in 1946.

Cable-stayed bridges differ from suspension bridges in that the cables run directly from the towers to the deck. While popular in Europe, they never gained acceptance in the United States.

Instead of relying on a contractor, the Liberty County Commissioners decided to use county forces to build the bridge and relied on portions of the original structure – the abutments and one of the approach piers – as part of the design.

“At its peak, eight men were employed on the job with construction equipment consisting only of a backhoe, a concrete mixer, 2-drum hoist … a winch truck, compressor and welding and burning equipment,” the nomination form states.

The cost to complete the bridge was $51,546, nearly $2,000 less than the engineer’s estimate.

Its deck has been replaced a few times, and problems with the camber, or arch, of the bridge deck from stretched cables also has been repaired.

“At the time of its completion, the Pugsley Bridge stood as the only bridge of its type in Montana and, according to Thomas Hurdle and contemporary civil engineer Dennis Nottingham, the only example of this design in the United States,” according to the nomination.

On Sept. 16, the Montana State Historic Preservation Review Board voted to recommend inclusion of the home on the federal register. The nomination now goes before the National Park Service for a final decision. Qualified properties can receive preservation benefits and incentives.

For more information, contact Eve Byron, public information officer, at 406/444-6843 or eve.byron@mt.gov