Yosemite shutters sites over danger from falling rocks

Paul Sakuma / AP file

This boulder was among those that crashed into Curry Village in Yosemite National Park in 2008.

By Miguel Llanos, msnbc.com

Yosemite National Park will no longer allow lodging 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.?

Some 20 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 fenced off 233 of the 600 cabins in the village after the scare.?

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Other areas that will close include:

• Two dorms housing 20 employees and parts of three others built in 1999, worsening a critical staff housing shortage;
• A half-dozen sites at Camp 4, a $5-a-night bargain near El Capitan used mainly by climbers;
• The LeConte Memorial, which includes a library and educational site.?

The park expected the ban on lodging and structures in high risk areas would "reduce the overall risk ... by 95 percent."

National Park Service

Rockfalls confirmed in the Yosemite Valley between 1857 and 2009.

The greatest 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 rock falls.

An Associated Press report after the 2008 fall found that while Yosemite officials were aware of earlier U.S. Geological Survey studies showing Glacier Point was susceptible to rock falls they did not warn visitors and repaired and reused rock-battered cabins.?

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.

Rock falls 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 rock falls have been documented at Yosemite, the park stated.?

The Associated Press contributed to this report.

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