NPS / provided A section of Big Oak Flat Road, the paved route that connects Tuolumne County and Highway 120 to Yosemite Valley, is closed indefinitely due to storm damage in one of the Central Sierra's wettest winters on record. 6122982

NPS / provided A section of Big Oak Flat Road, the paved route that connects Tuolumne County and Highway 120 to Yosemite Valley, is closed indefinitely due to storm damage in one of the Central Sierra's wettest winters on record. - union democrat

NPS / Provided Big Oak Flat Road in Yosemite National Park is cracked and collapsed, cutting off paved access to Yosemite Valley from Highway 120 and Tuolumne County. 6122981

NPS / Provided Big Oak Flat Road in Yosemite National Park is cracked and collapsed, cutting off paved access to Yosemite Valley from Highway 120 and Tuolumne County. - union democrat

NPS/ provided National Park Service personnel examine damage to Big Oak Flat Road, the only paved access for motorists to reach Yosemite Valley from Highway 120. The road is closed indefinitely. 6122980

NPS/ provided National Park Service personnel examine damage to Big Oak Flat Road, the only paved access for motorists to reach Yosemite Valley from Highway 120. The road is closed indefinitely. - union democrat

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For updated road and weather conditions in Yosemite National Park, call (209) 372-0200 and press 1.

The winding Big Oak Flat Road that allows motorists from the Bay Area, Sacramento, Stockton, Sonora and Groveland to reach Yosemite Valley from Highway 120 is closed indefinitely due to storm damage, and there is no timetable to have the vital tourism route reopened.

A contract for repairing the road has yet to be awarded, Doug Hecox, with Federal Highway Administration public affairs, said Friday in a phone interview. Hecox indicated repairing the road could take weeks or months.

For updated road and weather conditions in Yosemite National Park, call (209) 372-0200 and press 1. View More

One of the wettest winters in a century of weather records has pumped up volumes in the multitude of streams, creeks and other waterways that helped carve Yosemite Valley over millennia.

The rushing cascades include Rattlesnake Creek, which is near the place where Big Oak Flat Road, a former wagon route that clings to steep slopes, has cracked and failed.

200 feet long

“We’re working with the federal highway engineers, they’ve been out and looked at it,” Scott Gediman, with Yosemite National Park public affairs, said Friday.

“They understand this is a major road into Yosemite Valley, for visitors and businesses on the 120 corridor. We understand the importance of the road and the impact the continued closure is having,” he said.

A crack in the Big Oak Flat Road pavement is 2 to 3 feet wide in places. A section of the roadbed that reaches under the center line has collapsed and dropped 2 to 3 feet. The damaged stretch of Big Oak Flat Road that has to be excavated and rebuilt is about 200 linear feet, Gediman said.

“Over the past several weeks the road has been open and closed a few times,” Gediman said. “We’ve noticed the crack forming in the road. We see the road is undermined. Clearly it’s failed. The crack is getting bigger. It’s widening.”

Saturated ground

Workers are going to have to dig and get down under the existing pavement and roadbed to a point where the underlying soil and rock is stable, Gediman said.

“That is part of the challenge of putting a timetable on it at this point,” Gediman said. “Until they can dig down and assess slope stability, we don’t know how long it will take.”

Like so much of the Central Sierra right now, the ground under Big Oak Flat Road is saturated, Gediman said.

“We’ve had a huge winter so far,” he said. “A tremendous amount of rain and snow and runoff has come down. We have a lot of creeks and streams and a lot of water that’s contributed to this.”

As of Friday afternoon, the only access on a paved road for motorists to drive into Yosemite Valley was Highway 140, El Portal Road. Highway 41, Wawona Road, is closed just south of the park entrance, also due to storm damage.

“Clearly there’s a lot of interest in getting Big Oak Flat Road open because we have two of the three main roads closed,” Gediman said. “Maybe next week we’ll have a better idea of then it can be opened.”

‘We anticipate the project will be completed within one season’

Hecox, with the Federal Highway Administration, is based in Washington, D.C.

The contractor for the Big Oak Flat Road project has not yet been named, Hecox said Friday.

“We expect that will happen early next week, which would allow work to begin soon after,” Hecox said. “We anticipate the project will be completed within one season, but the specific timetable of the project won’t be known until the work can begin.”

The road embankment failed due to heavy rains, Hecox said. The nature of the work will be primarily embankment reconstruction and stabilization, along with needed road reparations.

Hecox said no cost estimate for the project was available Friday because a winning bid on the work had not yet been identified. Releasing a cost estimate publicly could influence contractors to lower their bids.

Old wagon roads

Like so many roads in the Mother Lode and up around the Central Sierra crest, Big Oak Flat Road started out as a trail and a wagon road. Some sections have been improved over time, first for stagecoaches, and later for automobiles. Some sections have been rerouted from the original routes, to eliminate steep sections only sure-footed horses, mules and oxen could handle a century ago.

A 1955 book titled “The Big Oak Flat Road” by Irene D. Paden and Margaret E. Schlichtmann includes accounts of some of the first white families to live in Yosemite Valley, who traveled into the valley via switchbacking cliffside trails fit for people on foot only.

The book includes mention of two “ uproarious festivals” staged in Yosemite Valley in 1874, a month apart, to make the successful entry into the valley floor of two competing, rival roads, Coulterville Road and Big Oak Flat Road.

“Stages could now unload sightseers at the hotel doors — tired, yes, but probably with a nominal amount of bruises and able to dine comfortably from a table,” Paden and Schlichtmann wrote.

The dawn of the 20th century brought automobiles, even though it was not yet legal for them to venture into Yosemite Valley.

A. E. and F. H. Holmes of San Jose drove a Stanley Steamer over the Wawona Road in July of 1900 and are acknowledged to have brought the first car into the valley, Paden and Schlichtmann wrote . The first auto that came into Yosemite Valley via Big Oak Flat Road was a Locomobile and it arrived in 1901.

By 1913, automobiles were legal on Wawona Road and in 1914 they were allowed on Big Oak Flat Road and Coulterville Road.

“For a quarter of a century the old roads deteriorated while a new low-level highway up the Merced River in time replaced even the railroad, causing it to be abandoned in 1945,” Paden and Schlichtmann wrote.

In 1940, Big Oak Flat Road was rerouted from Crane Flat to the valley floor, and a switchbacking section known as the Zigzag was eliminated.

Options off Highway 120

Motorists on Highway 120 can still use Evergreen Road to access Hetch Hetchy Road and trailheads at O’Shaughnessy Dam and Hetch Hetchy Reservoir. A section of Big Oak Flat Road remains open, providing access to the Merced Grove of Giant Sequoias, Crane Flat and the Tuolumne Grove of Giant Sequoias.

Highway 120 east of Crane Flat, known as Tioga Road, remains closed for the winter. When it opens in April, May, June or July, it provides access to Olmsted Point, Tenaya Lake, Tuolumne Meadows and Tioga Pass and Highway 395 on the Eastside Sierra.

The National Park Service has waived entrance fees for visitors entering Yosemite via Highway 120.

Woody Smeck, acting superintendent for Yosemite National Park, said people are working to get Big Oak Flat Road open into Yosemite Valley as soon as possible.

“We fully understand that this is a major impact to park visitors and businesses along the highway corridor,” Smeck said. “We are working as quickly as we can to get the road reopened safely.”

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