Ebbetts Pass, Sonora Pass and Tioga Pass , the highest-elevation paved routes over the jagged spine of the Central Sierra, are still locked in winter with snow-depths over 15 feet in places and overnight lows in the teens to low 20s and daytime highs in the 30s.
Thanks to heavy precipitation in March, snowpack and snow-water equivalence in the Central Sierra remained at 165 percent of average as of Tuesday. Forecasters said a storm passing northeast over the Central Sierra was expected to bring 4 to 6 inches of new snow to Ebbetts and Tioga passes, and 6 to 8 inches to Sonora Pass by Tuesday evening.
Nevertheless, Caltrans people in Stockton say workers plan to start clearing Ebbetts Pass on April 8, and they say their goal is to have Ebbetts Pass and Sonora Pass open to the public no later than the Friday before Memorial Day weekend. This year, Memorial Day falls on May 27, so the Caltrans target date for opening Ebbetts and Sonora passes is May 24, less than eight weeks away.
Heavy snow on Tioga Road and Tioga Pass, names for Highway 120 in Yosemite National Park, likely mean they’ll remain closed past Memorial Day, according to National Park Service staff. Late-season storms, snow accumulation and snowpack-related damage can sometimes delay pass openings. Yosemite National Park staff say park workers will begin plowing Tioga Road and Glacier Point Road this month.
The latest opening date for Ebbetts Pass since the winter of 1940-41 was less than two years ago on June 30, 2017, according to Caltrans. The previous latest opening date before that was June 26, 1942. The latest opening date for Sonora Pass was June 26, 1956. The latest opening dates for Tioga Road since 1980 were July 1 in 1998, and June 29 in 1983 and 2017.
Ebbetts Pass rises to 8,730 feet elevation in Alpine County and connects Calaveras Big Trees, Arnold, Murphys, Angels Camp and the rest of Highway 4 in Calaveras County with Markleeville on Highway 89 and U.S. 395.
Sonora Pass stands at 9,624 feet on the Tuolumne-Mono county border, and it is the high point connecting Sonora and the rest of the Highway 108 corridor to Bridgeport.
Tioga Pass is 9,945 feet, the highest route over the 400-mile-long Sierra Nevada range. Tioga Road and Tioga Pass connect Highway 120 and the rest of Tuolumne County with Tuolumne Meadows and access to the highest peaks in Yosemite, as well as Lee Vining and Mono Lake on the east side.
Caltrans District 10 staff in Stockton say that opening passes each spring usually involves more than removing snow. After snow is removed, blocked drains and culverts need to be cleared and cleaned out, and downed signs need to be replaced. Boulders and downed trees need to be removed. Roadside ditches have to be re-graded to prevent spring runoff from flooding the roadway. Pavement is repaired, cracks are sealed and roadways are re-striped in some locations.
Opening snowclad Central Sierra passes each spring can be dangerous work, especially in the wake of significant snowpack winter seasons. Avalanches of rock and snow and other springtime road-clearing activities have killed and injured workers on Tioga Road, Highway 108 and Highway 4.
The most recent worker death on Tioga Road was June 13, 1995. Barry Lee Hance, 43, a National Park Service employee and resident of Groveland, was operating a bulldozer 400 yards east of Olmsted Point when a snow avalanche collapsed and buried him and his machine. An autopsy showed Hance died of major blunt force trauma to the chest, which caused rapid suffocation.
On May 17, 1984, Sammy Lee Smallwood, 52, a National Park Service maintenance worker for 30 years, was with a crew using dynamite to move rock at Little Blue Slide on Tioga Road one mile east of Tuolumne Meadows. Smallwood was wearing a helmet when he was struck in the head by a large flying rock. Smallwood died in a helicopter during airlift to Modesto.