Nature Lures Some of Us to Live on the Edge
Not long ago the editor of the Outdoors section asked me to go trout fishing in the San Gabriel Mountains and write about it. Naively, I didn’t know you could find trout just minutes from the metropolis. Nor did I know much about the secrets of the San Gabriels, even though I often see their sheer face on winter days, framing one of the world’s most dramatic cityscapes.
As a primer, the editor gave me John McPhee’s 1988 “Los Angeles Against the Mountains.” So I happened to be reading about the history of San Gabriel mountain debris flows -- rock and mud, and everything in their path -- when the recent storms hit, and a saturated Southern California began to slip a disc here and there.
McPhee had learned two things from Caltech geology professors in Pasadena:
First, thousands of years of quaking has shattered the San Gabriel Mountains like dropped china, creating the possibility of unprecedented slides that could destroy sprawling foothill developments from Glendale to Glendora.
Second, most of the geologists lived in harm’s way. California’s natural allure is so powerful, it can seduce even the greatest minds.
I called Caltech to see if geologist Leon Silver, who had taken McPhee up to the roof of his Caltech building to explain the epic local history that predates man, was still around. Silver, who’s been at Caltech since 1948, is still plugging away just shy of 80. The professor emeritus picked up on the first ring.
“Come down to my office in the sub-basement of the North Mudd building,” he said, a name I thought he was making up until I arrived. “That’s where they put the really old geezers.”
Silver, with curly white hair and a wild brow, had a request when I arrived:
“Please don’t make me a doomsayer.”
But tragedies in La Conchita and a few other places the last several days were minor, Silver said, compared to the potential for disaster when the ground is this saturated. If ever there’s a major earthquake when it’s this wet, Silver said, watch out.
The hazard is greatest where fire has destroyed the chaparral root system that binds the earth. Late in 1933, fire ravaged the area above Montrose and La Crescenta, and then came rain to end the world. On New Year’s Day in 1934, a debris flow -- rock and mud sliding off the mountains -- buried Montrose, killing 34 people and destroying hundreds of houses.
After my brief history lesson, Silver took me up to the roof of North Mudd, and the San Gabriels towered before us in the brilliant winter light that follows wet gloom. Mt. Baldy was a great white confection in the distance.
Fifteen miles beyond the top of the range, Silver said, is the San Andreas fault.
“There is no place in North America as geologically active,” he told me, explaining how the Pacific Plate we were standing on is moving northwest, while the North American Plate grinds to the southeast. As McPhee described it, Bakersfield is heading toward Mexico City while Burbank is lurching toward Alaska. The Santa Monica and San Bernardino mountains are as cracked up as the San Gabriels.
The San Gabriels are rising even faster than they’re disintegrating. Over approximately 3 million years, thousands of tons of mountain erosion have been washed downhill. This created the gradual slope, inhabited by hundreds of thousands, that slides all the way to the Caltech campus and beyond.
Dozens of catch basins, some the size of football stadiums, were built at a cost of millions to catch debris flows from higher elevations. But the basins can’t catch everything, and there was minor damage to a relatively small number of homes in the last week. Even so, Silver said, many people living in the shadow of the mountain have no idea what lies overhead.
But he does. So why did he live at the base of the mountains, with his wife and two children, before settling in the lowlands of Arcadia?
“This is one of the finest climates in the world, the view is spectacular, the frequency of danger is long-term, and people have short memories,” he said, capturing perfectly the live-for-today ethic of a place where natural glory and impending doom sleep together. “And I, as a geologist, can pick the places that are less risky.”
Silver turned to me with the eyes of a child.
“Shall we go up the mountain?” he asked.
In his Toyota, we cruised past the Devil’s Gate Dam and beyond the Jet Propulsion Laboratory, turning onto the Angeles Crest Highway and up an incline with houses on both sides.
“This is the kind of country that could get hit incredibly. You see all those houses up there on the rim? Those are million-dollar houses, and you want to ask, do they know where they are, and did they ask the right questions when they bought?”
A sign says to watch for falling rocks the next 55 miles. Past that we hit a roadblock, with minor slides fanning onto the roadway just ahead. Silver sweet-talks Caltrans workers into letting us walk beyond the barricade.
“That’s bedrock, and this is a little fan,” Silver tells me, pointing to a 15-foot-tall cone of brown mush that has slipped down the face of the mountain and oozed onto the side of the road.
We walk a little farther and suddenly he’s tramping through a larger fan, his brown leather shoes sinking into the muck.
“Now you see this bedrock here?” he asks, touching what looks like solid rock. “Watch this.”
He paws the rock, and in a Superman move, easily breaks off a chunk. He invites me up to do the same, and reminds me that the San Gabriels are lousy with porous and crumbling rock. When the steep mountainsides become heavy with rainwater, look out below.
Yes, there has been too much foolish development and defiance of nature here and in many other parts of Southern California. But in the region’s geologic time, there is no questioning who holds the upper hand. Every time we forget, there’s a new lesson in humility.
In the dying light of day on the way back, Silver talks about hiking through the San Gabriels with his kids when he was a young man. He tells me how much he misses living up where cool air moves down off the mountain at night, and a good rain brings up the smell of the chaparral.
“Yeah,” he says, driving us down through the centuries and toward the sea. “I’d roll the dice again.”
Steve Lopez can be reached at steve.lopez@latimes.com.
