YOSEMITE NATIONAL PARK, Calif. (AP) — There may be no more potent reminder of California’s humongous snowfall than the plows still clearing roads that snake across the state’s highest mountains as summer approaches.

Crews have been digging, blowing and blasting for months — and the work is not finished, though an approaching heat wave could speed up the process.

“We’re almost at the middle of June and we still have lots of passes that aren’t open,” said Florene Trainor, a spokeswoman for the California Department of Transportation.

Few roads traverse the Sierra Nevada, the rocky spine running 400 miles (644 kilometers) up the state that is home to Yosemite National Park. Mountain passes are typically open by Memorial Day.

The only road through Yosemite, Highway 120, remained closed at the park’s eastern entrance this week as crews dig out from snows that topped 20 feet (6 meters) and drifted well over 50 feet (15 meters).

On a recent day, the eastern entrance station at 9,945-foot (3,031-meter) high Tioga Pass was buried in snow.

But the serenity of the Sierra Nevada, with birds chirping beneath snow-crested peaks that tower above 12,000 feet (3,657 meters), was shaken by the roar and beep of plows, excavators and massive machines carving through towering snowbanks and moving giant blocks of snow. Big snow blowers sent plumes arcing through the air and off the side of the road.

As the Caltrans crew dug the entrance out from the east, a crew from the park was working from the west to clear the road that winds its way to Yosemite Valley, the park’s top destination.

Caltrans had begun inching its way up the treacherous road more than two months ago when it seemed more like winter. It snowed on and off throughout the spring, with a late-season storm hitting last weekend.

The air is clean and views are stunning, but working here is not for the faint of heart as drivers maneuver large machines along narrow ribbons that feel suspended above an abyss. Helicopter footage shot this spring for Caltrans showed the small margin for error in places where the road clung to cliffs and then vanished under a white blanket where the path was obscured.

“It’s spooky, it’s nerve-wracking … especially when you can’t see the road. You’re on a big sled,” said Clint Weier, a maintenance superintendent with Caltrans. “Some of our operators up here have had some wow factors.”

Avalanches stampede down granite walls, taking trees and rocks with them that choke roads. In one section already plowed, tree trunks and branches from a previous slide poked from sheer snowbanks littered with pine needles and other debris from a previous snow slide.

Rockslides pose a threat even after workers use charges and other methods to release snow slides to alleviate the danger. Slides and the crushing weight of the snowpack damaged guardrails in some places that serve as the lone barrier between the road and a precipitous drop that plunges hundreds of feet east of the park entrance.

A Yosemite plow driver was killed by an avalanche in 1995 and now maintenance workers in the park complete avalanche safety courses to work on the road, park spokesman Scott Gediman said.

The park’s official map notes that the eastern entrance atop the state’s highest automobile pass is typically closed through May, but it usually opens later after a snowy winter, Gediman said Tuesday. There’s no date yet to open the road through the park.

Just to the north of the park, Sonora Pass opened Tuesday. Ebbetts Pass farther north remains closed for repairs. To the south, crews this week plowed the road leading to Devils Postpile National Monument.

In Lassen Volcanic National Park, much farther north, deep snow still buries the road that circles the southernmost peak in the Cascade Range. The road is expected to open in early July — earlier than some previous years.

The snowpack presented an additional challenge this year because it was heavily saturated with water. Dense and frozen snow was harder to cut through, heavier to move and broke equipment, said Paul Jensen, a Caltrans plow driver.

Jensen has been working overtime all spring to get the road into Yosemite open and hasn’t minded working weekends. He considers it a labor of love.

“Twenty years and I’m still not tired of it,” Jensen said. “It’s my favorite time of the year.”

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This story has been updated to clarify that the eastern entrance to Yosemite is closed.WHAT OTHERS ARE CLICKING ON:

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