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After record-breaking snow in the winter of 2022–2023, the 69-foot San Joaquin Bridge in Kings Canyon National Park failed catastrophically. It was the main crossing on the John Muir Trail / Pacific Crest Trail (JMT/PCT) for thousands of hikers and horseback riders, and its loss forced them onto long, dangerous detours through rugged country.

The broken, twisted wooden bridge above a raging creek.

The old wooden bridge after a storm, broken and twisted above a raging creek. NPS

A temporary crossing

The Park Service moved quickly, finishing the new bridge in September 2024. In the meantime, the Denver Service Center (DSC) and the construction contractor put in a temporary cable bridge, letting up to 60 backpackers a day cross and greatly easing the disruption.

A thru-hiker crossing a narrow temporary bridge of wood planks and guide wires over a calm creek.

A PCT thru-hiker crosses the temporary bridge. NPS

Building in the wilderness

The DSC did all the design — plans, specifications and cost estimates — and ran the construction contract, working closely with park staff to account for the site's constraints. The challenges were many:

  • a short season, with snow at elevations above 8,300 feet;
  • every material flown in by helicopter — and helicopters were scarce during California's long fire season;
  • tight deadlines for safety;
  • respect for the historic original bridge and the sensitive landscape;
  • no helicopter flights during bighorn sheep lambing season.

A helicopter carrying a bridge component on a long line.

A helicopter flies in parts of the new bridge, assembled off-site. NPS

Engineers used satellite internet for live video meetings with the crews, improving communication and safety, and solar power and battery-operated equipment to lighten the project's environmental footprint.

Done early, under budget

The bridge was finished ahead of schedule and under budget, awarded and built for $1.25 million, just 17 months after its failure was discovered.

A pack llama loaded with gear stands with its handler in front of the finished bridge.

Trail users of every kind — llamas included — were eager to cross the new bridge. NPS

The project, highlighted during Engineers Week 2025, shows how Park Service engineers keep parks accessible and protected — from fragile ecosystems to historic landmarks — even in uncertain times.

Sources

Based on "Engineering a Brighter Future: Restoring the San Joaquin Bridge in Kings Canyon National Park," National Park Service; a work of the United States government in the public domain.

言語English

ライセンス: CC0 1.0(パブリックドメイン) · 出典 www.nps.gov

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