Three Sierra passes that are typically open by Memorial Day weekend are still blocked by snowdrifts that Caltrans crews report are as high as 40 feet.
uTioga Pass — Highway 120 through Yosemite —  may not be cleared until late June or early July based on similar snowfall in previous years. Plowing has been stopped after crews reached an area that has significant avalanche danger. Yosemite Park officials do not have an estimated opening date. Tioga Pass is the state’s highest paved highway cresting the sierra at 9,943 feet.
uSonora Pass on Highway 108 is also closed. Caltrans reports travelers can get as far east as Kennedy Meadows. It is the first time in more than 10 years that the pass that is some 321 feet lower than Tioga Pass hasn’t opened by Memorial Day.
uEbbetts Pass on Highway 4 at 8,730 feet is also closed with travelers being able to go as far east as the eastern end of Lake Alpine. It is the second time in the past decade Ebbetts Pass hasn’t opened by Memorial Day weekend.
Caltrans believes they can open both Ebbetts and Sonora within three to five weeks.
Besides snow removal they also need to clear rocks, trees and shrubs that accumulate on roadways during winter storms.
Caltrans crews are working on Highway 108 and Highway 4 seven days a week. They started work on clearing mountain passes in April. They have succeeded in getting Monitor Pass on Highway 89 open.
A Caltrans releases notes even during years of light snow, Ebbetts Pass and Sonora Pass are challenging when it comes to clearing, repairing and opening the roads. Ebbetts has grades in excess of 23 percent and Sonora has grades that top 20 percent, far beyond typical highway grades of 6 percent. The steep grades, high elevation and narrow lanes on these highways are unable to accommodate snow removal equipment and vehicular traffic at the same time.
For the latest in highway information call the Caltrans Road Condition Hotline at 1-800-427-ROAD (7623).
Meanwhile rising temperatures are sending more water down the Merced River to combine with the heaviest run-off in 20 years from the Tuolumne and Stanislaus river basins to keep water levels high especially on the last leg of the Lower San Joaquin River south of Manteca before it reaches the Delta.
Emergency workers are warning people to stay out of the rivers if they lack the expertise and the equipment to safely navigate the swift and cold water.
The flow on the Stanislaus River is substantially higher and colder than it’s been in more than a decade. With more than a million acre feet of water estimated remaining in the snowpack above New Melones Reservoir, it could be until the end of August to see flows return to normal levels.
In the past five days the Stanislaus River between Knights Ferry and Manteca has had two serious river mishaps requiring the response of four fire departments. One man ended up drowning.
Up and down the western Sierra watershed drownings have picked up significantly in the past month as swimmers, anglers, and boaters severely misjudge water conditions.
Besides high flows and cold water there is also a substantial increase in debris as well as more snags and possible way of becoming being entangled with debris lurking under the water’s surface.

To contact Dennis Wyatt, email dwyat@mantecabulletin.com