Slippery odds for a mountain road

Those repairs — and work on the storm-damaged roadbed and drainage systems — total $16.5 million. Since then, he's driven this stretch once a week from downtown Los Angeles to check on the progress.

One morning this summer, Ortega stood on the road above Niño Canyon, talking to the foreman. Twenty feet away, a bulldozer teetered over the shoulder and then dropped, blade first, down a slope, pushing a mound of dirt to a pad 60 feet below. The grade seemed almost vertical.

"Just about 45 degrees," Ortega said, making a quick calculation, a useful skill in mountains so precipitous that sometimes it seems that only friction is holding them up.


Right now the slope is too steep to support the road, he explains, but when the work's completed, it will be close to 33 degrees, enough to give two lanes proper purchase on the reinforced mountain.

Why the highway failed is no mystery. In the aftermath of the Station fire, the U.S. Forest Service predicted an "increase in destructive debris flows … racing down channel bottoms in a slurry similar to the consistency of concrete, in masses from a few hundred cubic yards to hundreds of thousands of cubic yards of saturated material, destroying everything…."

The prediction came true. The slurry filled drains and debris basins along the highway. During each storm, the road became its own flood control channel, and the runoff poured over the shoulders, undermining the foundation as it eroded the slopes.

Maintenance tried to keep up, but the downpours overwhelmed them. Mt. Wilson recorded 6.94 inches of rain in one hour during that February storm.

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State Route 2, as Angeles Crest Highway is officially known, is as improbable a road as Los Angeles is improbable a city. Both exist outside the laws of nature.

The route always looked good on paper: a 60-mile loop extending out of La Cañada Flintridge into the mountains and then, under the original plan, back into the city. It would begin at 2,000 feet and top out close to 8,000, bringing firefighting capabilities to the Angeles National Forest and Angelenos to its bucolic splendor. Construction started in October 1929.

Engineers plotted curves and grades on 100-key desk calculators, and surveyors in hip boots and pith helmets headed into the field. Hard labor was provided by the homeless and the convicted, enlisted from unemployment queues and state prisons. With mules, wagons, picks, steam shovels and dynamite, they pushed their way forward.

The results were deemed "a miracle of modern engineering," as a reporter for The Times wrote in 1932. "In a few short years, any Angeleno with even a brief half day for escape can head into the mountain wind and in one ecstatic hour, find peace in a play-land that will forever prove panacea for all the hurts of his city-worn body and soul."

The final stretch of road into Wrightwood opened on Nov. 8, 1956, but by then, this play-land had become a little less idyllic. "Angeles Crest Traffic Stirs Resident Lament," read one headline. Others followed: "3 Killed, 3 Injured in 500-Ft. Auto Plunge," "Model Found Stabbed to Death Beside Road," "Confession Reported in Big Angeles Fire."

No longer merely an escape from the city, the highway had become just another road connecting far-flung points in Southern California, even if the mountains didn't always cooperate.

Easy to overlook but impossible to deny, the San Gabriels are among the fastest-rising mountain ranges on Earth and one of the most quickly eroding. Stones found on the roadside today were buried a mile deep 5 million years ago, testimony to how brittle these peaks are and to the intensity of the periodic storms that tear at them.

Which makes the maintenance of the highway all the more Sisyphean. In 2005, when winter storms almost broke a century-old record for rainfall, the agency had to close the route near Wrightwood for more than four years. Those repairs cost $10.5 million.

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Later that morning, Ortega parked in the shade near Brown Canyon. The work here was almost finished, February's damage almost completely erased.

Initially there was talk of abandoning the hillside contour here and building a bridge, but Ortega proposed a less complicated solution. He wanted to reconstruct the slope using material that had washed down the mountain.

The result is a graceful arc of shoulder and road, a little more than two football fields long, set above a well-proportioned amphitheater of dirt that will be covered with a honeycomb sheet to protect it against rain and runoff.

Across the road, where there was a 36-inch conduit to drain excess runoff from a debris basin, he called for a 10-foot-by-10-foot culvert that would channel water beneath the highway into a concrete flume down the embankment and into the creek below.

In addition, a 100-foot-wide and 15-foot-high steel-mesh fence, specially designed to hold back debris, will span the canyon above the road.

He was not about to take any chances.

The Angeles Crest isn't in the clear. Summer was easy — no lightning stikes, no fires. The Scotch broom and buckwheat had returned. The mountains are recovering, but each winter brings uncertainty.

Above his desk on the 11th floor of the Caltrans building, Ortega keeps a newspaper clipping showing a bar graph of local rainfall totals since 1990. Last year measured a little less than an inch and a half above average, 16.36 inches.

That was nothing. It's the prospect of repeating 2005 that worries him most. Its measurement — 37.25 inches for the season — is almost off the chart.

thomas.curwen@latimes.com