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Yosemite closes more cabins, campsites due to danger from falling rocks

Several campsites and cabins are closing down in areas thought to be at greatest risk for falling boulders. NBC's Brian Williams reports.

Yosemite National Park is shuttering cabins, campsites and other structures in areas found to be at greatest risk of boulders crashing down.

In a statement released Thursday, the park said it made the decision after a new study for the first time delineated "a rockfall hazard line" in the Yosemite Valley. 

Eighteen more cabins will be off limits in Curry Village, where in 2008 the equivalent of 570 dump trucks of boulders from the 3,000-foot-tall Glacier Point hit 18 cabins and sent visitors fleeing for their lives. The park closed 233 of the 600 cabins in the village after the scare, and later relocated 125. The 18 closed Thursday will be relocated to safer areas as well.

Other areas impacted include:

  • Two employee dorms and parts of three others will close, forcing the park to move 30 staff and worsening a critical housing shortage;
  • Eight campsites at Camp 4, a $5-a-night bargain near El Capitan used mainly by climbers, will be relocated nearby;
  • The LeConte Memorial, which includes a library and educational site, as well as the Curry Village Amphitheater will host fewer programs. 

The park expected the decision would "reduce the overall risk ... by 95 percent."

Park spokesman Kari Cobb emphasized to msnbc.com that the park is "fighting against" erroneous news reports suggesting that park areas are being closed off to hikers. It's the structures and campsites, not the recreational areas, being impacted, she said.

National Park Service

Rockfalls confirmed in the Yosemite Valley between 1857 and 2009.

The greatest rockfall dangers are within 180 feet of the base of the cliffs, the study concluded, while adding that there is also a 10 percent chance a potentially deadly boulder will fall outside of the zone every 50 years. 

The Yosemite Lodge and the Ahwahnee Hotel are not located in the danger zone. 

Laser mapping was used to create the first detailed look at the valley's towering cliffs, which ultimately could lead to identifying which ones are most vulnerable to rockfalls.

After the 2008 fall, the Associated Press reported that while Yosemite officials were aware of earlier studies showing Glacier Point was susceptible to rock falls they did not warn visitors and repaired and reused rock-battered cabins. 

Cobb noted that damaged cabins had been repaired since the park's early years and that since 2006, when Yosemite's first geologist was hired, "we have never intentionally left open cabins or other high visitor use areas that we know to be susceptible to higher probability of rockfall."

"It is impractical to put signs at every location that may pose a risk to visitors," she added. "We are surrounded by 3,000 foot granite cliffs that actively experience rockfall about once per week at different locations. The most we can do is educate visitors and provide them safe accommodations while they are staying here."

Aug. 27, 2009: A tourist captured video of a rockslide in Yosemite National Park that forced the evacuation of the Ahwahnee Hotel. No injuries were reported.

Rockfalls in and around Curry Village have killed two people and injured two dozen since 1996, the AP stated. Since officials began keeping track in 1857, 15 people have died throughout the valley and 85 have been injured from falling rocks. 

More than 900 rockfalls have been documented at Yosemite, the park stated. 

The Associated Press contributed to this report.

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