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North America, United States, California, Yosemite, The Changing Face of Yosemite

The Changing Face of Yosemite. Yosemite National Park was the site of two major natural disasters in the year. A rockslide in June and a flood in January have kept the National Park Service on their toes. On the evening of Wednesday, June 10, a 500-foot long arch broke from the top of an overhanging cliff between Glacier and Washburn points. The 31,500-ton block bounced off the face once in its 2,000-foot drop before landing 200 feet from the base of the cliff. Ed Youmans of Stateline, Nevada witnessed the event while soloing The Prow on Washington Column. At 6:46 p.m. he was on a ledge atop the third pitch when he heard a loud crack and low rumble.

“It went on and on. I could feel concussions in the air… I could feel them in my chest,” Mr. Youmans recounted.

The arch crumbled on impact and sent out a dense cloud that blocked visibility in the eastern end of the valley. An air blast from the impact downed over 2,000 trees, some up to five feet in diameter.

Climbing Ranger Mark Fincher stated, “The trees were all pointing in the same direction and several inches of gray dust covered everything.”

The impact occurred in the busy Happy Isles area, near the terminus of the John Muir Trail and the Mist Trail to Vernal Falls. A snack bar was destroyed and the nature center near Happy Isles was damaged. The only fatality was Emilio Morales of Montabello, California, who was pinned under a tree near an ice cream stand. Falling trees injured 14 additional tourists, two of whom were seriously hurt. Tourists and rescue workers were treated for dust inhalation.

Rock continued to fall from the fracture well into Thursday, impeding rescue efforts. Rescue workers with dog teams thoroughly searched the area. Park Service officials said that they were reasonably sure they had found everyone. The National Park Service closed all routes east of Goodrich Pinnacle on Glacier Point Apron. Due to loose debris, 35-40 routes were closed for the rest of the season and were to be evaluated in the spring of 1997. The climbing routes and fixed anchors appear to be intact. This was the largest rockslide in Yosemite since the Three Sisters’ slide in 1980.

From January 1 through 3, 1997, the frothing Merced River closed all roads into the park. It was the largest flood in the recorded history of Yosemite. Approximately 900 visitors and concession employees were evacuated from the park. Highway 140 was washed out for 200 feet with drop-offs up to 30 feet at the Cookie Cliff turnout. Sewage lines and water pumps were blown. The Upper River and Lower River campgrounds, as well as parts of the Lower Pines area, were completely washed out.

The concession employee tent-cabin area known as Camp 6 was destroyed. Tent cabins and vehicles were upended. Cabins and hotel units were wrecked. Picnic tables were swept into trees and on bridges. The Park Line Restaurant at the Yosemite View Hotel had to be bulldozed. Rehabilitation and cleanup costs were estimated at $178 million. Brian Huse, National Parks Conservation Association Pacific Regional Director, states, “This is a once-in-a-lifetime chance for the Park Service to turn disaster into an opportunity—to restore natural processes in Yosemite Valley by moving administrative and visitor facilities out of the floodplain.”