Hillsides are ‘weeping,’ falling on California’s mountain highways

As the rain and snow have fallen this winter, so have California’s hillsides, forcing the closure of major roads through the Sierra Nevada and causing millions of dollars in damage.

The California Department of Transportation estimates that the winter’s pounding storms have caused $400 million in damage to California highways. And the worst may still be coming.

Caltrans officials said they hope to keep Interstate 80 and Highway 50 open throughout Presidents Day weekend, but travelers should be aware the door could shut at any moment as a series of storms dumps more rain on already saturated mountainsides.

Interstate 80 has been closed twice since January by slides that spilled dirt, rocks and trees across all lanes, at some points 7 feet deep, leaving crews scrambling for hours to clear a path while commercial trucks backed up at the Nevada state line.

The most recent slide, in the Baxter area east of Colfax, has been cleared, and concrete barriers are in place. But the 200-foot-wide slope is still soaked and “active,” officials say, and is being monitored.

Highway 50, which runs through a steep canyon where recent wildfires have denuded hillsides, was hit with seven road-closing slides this month. One slide hit three cars, shoving one across the roadway and pinning it sideways against the far guardrail, highway officials said. A tree tumbling down a hill hit another car. There were no reported injuries in any of those incidents, although a woman was killed by a falling tree in January on Highway 89 south of Truckee.

Highway 49 has been hit hardest of major mountain roads, with two dozen blockages and other problems that required fixing in recent weeks.

It’s been the winter of mudslides, Caltrans spokeswoman Liza Whitmore said. “Who would have thought (we’d) have two mudslides that completely close 80?”

The mountainside at Baxter provides an example of what is happening on hillsides throughout the foothills and mountains. “It’s weeping,” Whitmore said. “Water is just flowing out from everywhere, as if there is a spring somewhere in there.”

State hydrologist Clark Townsend is among the Caltrans specialists who have been heading to slide areas to design quick repairs aimed at getting the road open and to plan longer-term fixes.

“No matter what you do, you’re probably not able to stop all forces from landslides,” Townsend said. “When you have saturated soil, it is liquid and can flow down a hill. When it flows, it has an awful lot of force.”

Thanks to Caltrans’ road-clearing efforts, tens of thousands of visitors are expected to pack into the Tahoe area for the three-day weekend. Hotels forecast they will sell out, and ski resorts are expected to be busy, said J.T. Thompson, tourism director for the North Lake Tahoe Resort Association.

Even when road conditions are difficult, travelers manage to find their way up, he said, especially this winter because of pent-up demand after years of drought.

Even the recent closures of I-80 failed to stem the flow of visitors, he said. “They came up (Highway) 20 and back down 20,” he said. “It’s been difficult to get up, but they still get up here.”

State highway officials reported this week they have spent an estimated $400 million on emergency repairs at nearly 200 highway trouble spots statewide this winter.

In the Sacramento and Tahoe areas, crews have dealt with 54 storm-related problems on state roads, totaling an estimated $42 million. The most costly are not mudslides onto the road surface, however. Instead, they involve slumped hillsides on the downhill side of highways, requiring Caltrans crews to construct retaining walls below the road to keep it from sagging or collapsing.

Valley highways are not immune to winter woes. Caltrans has begun closing lanes on Interstate 5 at night near the Sacramento-San Joaquin county line to repair broken concrete pavement slabs that have worsened with the wet weather and threaten to blow vehicle tires. The night work is expected to cause traffic back-ups of up to a half-hour.

Caltrans officials are using the work and its costs as ammunition to push for more maintenance and operations funding from state and federal sources. The governor and Legislature have said this spring they hope to come up with a way to provide more funding for transportation, with a focus on fixing crumbling infrastructure.

“The stress placed on the state highway system by extreme weather continues to underline the need for stable sources of transportation funding to maintain California’s aging roads,” Caltrans spokesman Patrick Olsen said in an email to The Sacramento Bee.

Caltrans Director Malcolm Dougherty issued a statement as well earlier this week, saying “our roadways have been pounded this winter by the severe weather conditions” and that his crews are working around the clock to repair and reopen damaged roads.

Tony Bizjak: 916-321-1059, @TonyBizjak

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