National Park Service: Worst rockfalls, landslides in Zion National Park

Posted by Jeff on Oct 25, 2015 @ 9:14 am in Hiking News | 0 comments | Last modified: October 25, 2015

A large rockfall recently closed state Route 9 in Zion National Park, prompting a look back at the worst rockfalls and landslides in the park’s history. The most recent rockfall occurred Wednesday, Sept. 23, 2015 and closed state Route 9 near the Pine Creek Bridge on a switchback near the Mount Carmel Tunnel, according to Zion National Park officials. The largest boulder in the fall measured around 19 feet high, 20 feet long and 15 feet wide and weighed 200 tons.

While September’s rockfall didn’t cause any fatalities or significant damage to buildings, that hasn’t always been the case with rockfalls in the park. Zion National Park has a long history of large landslides and falling rocks due to the tall cliffs and exceptional rate of erosion, park officials said.

“To get a feel for the frequency of small rockfalls, it has been my observation that there is at least one new rock in park roads or the roadside ditches almost every day,” Zion National Park spokeswoman Aly Baltrus said. “When in Zion Canyon or the backcountry hearing the clack, boom or clatter of a small rockfall is an almost daily occurrence. When it is raining, the frequency reaches a few per hour.”

Baltrus said although there have been some fatalities in the park’s history due to falling rocks, the number is relatively low due to the fact that visitors spend a relatively brief period of time in high rockfall hazard areas, like the immediate base of cliffs. My brother and I can relate, as we heard, and saw the cloud of dust of a rock fall while hiking to Scout Lookout.

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