La Crescenta Against the Mountains: In the Footsteps of John McPhee

Upper Shields Debris Basin

Note: In light of the sad and still unfolding story of lethal mud and debris flows at the base of recent burn areas across Southern California, I am re-posting the following, with minor revisions, from a personal blog originally written two and a half years ago.

los angeles basin map

crescenta valley map

Back in May 2015, I had a couple of free weekend hours while in the general vicinity of the Crescenta Valley, in metro L.A.’s northern foothills. It is an area I had driven through many times on the 210 freeway, but otherwise did not know very well, at least not in any sort of locally specific way—except for one suburban street and the somewhat famous house that sits at its base. (Follow this link to Google Maps to virtually explore the location on your own.)

That Pine Cone Road and the Genofile house are known by me, or to any extent beyond its local Pinecrest neighborhood, is due to the frightening events that took place one stormy February night in 1978, and to the fact that one of the country’s most prominent essayists so prominently featured these events in one of his most prominent books. Since its initial publication in 1988, John McPhee’s account of what happened on Pine Cone Road has become a staple of presentations on the hazards of debris flows (aka “mudslides”), on the challenges of living in naturally hazardous environments more generally, and on the complexities we face in managing our people-environment relationships. In other words, it is exactly the sort of story that we geographers love to tell.

Rather than tell that whole story here myself, let me share a portion of McPhee’s version:

Kimberlee Genofile called to her mother, who joined her in [brother] Scott’s room as they looked up the street. From its high turnaround, Pine Cone Road plunges downhill like a ski run, bending left and then right and then left and then right in steep christiania turns for half a mile above a three-hundred-foot straight-away that aims directly at the Genofiles’ house. Not far below the turnaround, Shields Creek passes under the street, and there a kink in its concrete profile had been plugged by a six-foot boulder. Hence the silence of the creek. The water was not spreading over the street. It descended in heavy sheets. As the young Genofiles and their mother glimpsed it in the all but total darkness, the scene was suddenly illuminated by a blue electrical flash. In the blue light they saw a massive blackness, moving. It was not a landslide, not a mudslide, not a rock avalanche; nor by any means was it the front of a conventional flood. In Jackie’s words, “It was just one big black thing coming at us, rolling, rolling with a lot of water in front of it, pushing the water, this big black thing. It was just one big black hill coming toward us.”

In geology, it would be known as a debris flow. Debris flows amass in stream valleys and more or less resemble fresh concrete. They consist of water mixed with a good deal of solid material, most of which is above sand size. Some of it is Chevrolet size. Boulders bigger than cars ride long distances in debris flows. Boulders grouped like fish eggs pour downhill in debris flows. The dark material coming toward the Genofiles was not only full of boulders; it was so full of automobiles it was like bread dough mixed with raisins. On its way down Pine Cone Road, it plucked up cars from driveways and the street. When it crashed into the Genofiles’ house, the shattering of safety glass made terrific explosive sounds. A door burst open. Mud and boulders poured into the hall. “We’re going to go,” Jackie thought. “Oh, my God, what a hell of a way for the four of us to die together.”

– Excerpt from John McPhee, The Control of Nature, as presented by the U.S. Geological Survey’s online student guide, “Land and People: Finding a Balance.” Like the book’s other two chapters, “Los Angeles Against the Mountains” was originally published in the New Yorker in September and October 1988. Several contemporary news stories covering the 1978 debris flows were collected and reprinted in the October 2009 newsletter of the Historical Society of the Crescenta Valley.

genofile home buried under debris

above: The Genofiles’ buried home in February 1978 (Historical Society of the Crescenta Valley)

Fortunately, the Genofile family survived that terrifying night, and they were able to share their story with McPhee a decade later, as well as with a local Crescenta Valley audience more recently. It is a story that never loses its very tangible local relevance, for the threat of violent debris flows at the foot of Southern California’s mountains is perennial. Residents of foothills communities are especially on edge at the beginning of any winter rainy season following wildfire on the chaparral-covered slopes above. Such was the case for Pinecrest in the Fall of 2009, after that summer’s Station Fire burned more than 160,000 acres—then the largest in L.A. County’s recorded history—and left Jackie Genofile and her neighbors anxiously awaiting what winter storms might bring. “Everyone was pretty panicky,” she told the L.A. Times.

In May 2015, upon visiting the site of such geological drama about which I had read so much, I was immediately struck by two things. First, on a lazy but not atypical Saturday morning, it is quiet in Pinecrest. Not suspiciously quiet, but peacefully quiet. McPhee describes the neighborhood as “serene”, but since his story revolves around the dramatic hazards associated with living on the margins of where the city meets the mountains, it is easy to lose track of just how beautiful and peaceful this neighborhood is. As another outside observer of Los Angeles, Reyner Banham, noted in his widely read architectural history of the metropolitan region, the foothills provide a stunning refuge from the traffic and the noise of the “Plains of Id” that lie below. Reading McPhee’s essay almost inevitably leads one to question, “Why would anyone want to live there?” But to actually visit the Pinecrest neighborhood just as inevitably leads one to oppositely ask, “Why would anyone not?”

genofile home today

above: The rebuilt Genofile house, now with a second story to (hopefully) stay above any future mud and debris, and in the meantime, to provide enhanced city and mountain views.

The second thing that immediately caught my attention during my visit is that the slopes of the Pinecrest neighborhood are steep! I used to be a competitive cyclist, and I still harbor middle-aged delusions of conquering the great climbs of the Alps and Pyrenees, but McPhee was spot on when he used another sport for his choice of metaphor. Pine Cone Road is just a few feet of snow away from being a candidate for the Downhill ski course at the Winter Olympics. This was apparent even while I was still in the car, repeatedly and nervously checking my brakes. Getting out of the car and walking only confirmed that these otherwise tame suburban streets could indeed serve as good training ground for climbing the slopes of Mount Whitney.

view down pine cone road

above: Looking down upper Pine Cone Road, with Shields Creek behind the fence in the channel to the right, before crossing under the street near the utility pole. Behind a moderate layer of haze in the background stand the skyscrapers of downtown Los Angeles.

view up pine cone road

above: The reverse view of the previous photo, looking back up at Upper Shields, with Shields Creek now on the left.

lower pine cone road

above: Looking down lower Pine Cone Road, around the last sweeping bend before reaching the Genofile house at the bottom. For the reverse view looking back up the hill from the Genofile house, alongside the same debris-filled view in 1978, see this post on the website of the Crescenta Valley Weekly.

steep pine cone road

above: Not far above the bend from which the previous photo was taken, Pine Cone Road gets really steep.

While McPhee listed the steepness of these San Gabriel slopes as one of several factors contributing to the severity of their natural hazard, he failed to note that this severe topography is not entirely natural. Or to state it a bit more precisely, the twentieth-century city was not at all humble in extending its sprawling reach well up onto those mountain slopes, into a setting that might be deemed, well, unnatural for urban living.

genofile home site 1916

The photo above comes from the collections of the Glendale Public Library. It is a view of the Crescenta Valley, circa 1916, looking northward toward the San Gabriels’ Mt. Lukens from a vantage point across the valley in the adjacent Verdugo Mountains. La Crescenta Avenue runs through the middle of the photograph toward the manicured clearing at the base of the mountains. This was Harvey Bissell’s “Hi-up Ranch”, a Crescenta Valley landmark throughout the first half of the 20th Century. In the postwar years, after serving for a short while as Alexander Markey’s “New Life Center”, the property was developed by local architect Webster Wiley into the Pinecrest neighborhood of today. In addition to its celebrated mid-century modernism, Wiley’s development is noteworthy for its substantial reconfiguration of the foothills topography. Rather than the gently sloping alluvial fan on which Bissell’s ranch largely sat, Pinecrest was extended much higher up the slopes as a series of terraced building platforms. Pine Cone Road cuts across this terraced grain, terminating at Upper Shields Basin, near the approximate location pointed out by the red arrow I have added to the photo.

terrace view homes

above: Great views from these Wiley terraces.

caution mountain lions

above: As the city extends into the mountains, the natural hazards include more than just fire and flood.

Providing current Pinecrest residents with a little peace of mind is the knowledge that the County has redoubled its efforts to protect foothills homes from the debris-flow hazard. In addition to strategically positioned sandbags and concrete K-rail barriers whenever there is threat of flood and flow, the local debris basins have been significantly upgraded. Today’s structure at Upper Shields—the one that protects the Genofile home—is far more substantial than what was in place in 1978.

upper shields gate

upper shields dam

above: Upper Shields Debris Basin


lower shields

lower shields basin

above: Lower Shields Debris Basin, which lies immediately below the Genofile home.

debris guardrails

above: Guardrails along Markridge road are more to catch falling debris than wayward automobiles—although much of the debris crashing into the Genofile home in 1978 did indeed include neighbors’ cars swept up with the boulders and the mud.

Despite the improved fortifications, and despite greater community awareness of the debris-flow hazard thanks to the historical memory of long-term residents such as the Genofiles plus the work of writers such as John McPhee nationally and Mike Lawler locally, the questions that McPhee implicitly raised back in 1988 remain valid today: Are these defenses enough? Is it safe, in whatever relative sense one uses that word, to live at the bottom of Pine Cone Road? Safe or not, is it wise to live there? Should society limit, or simply not facilitate through publicly funded infrastructure and maintenance, such amenity-rich urban living on the margins of the city? And especially in those gray spaces between the urban and the rural, the domestic and the wild, the artificial and the natural, how much control should we expect to have over the forces that potentially endanger, and/or enrich, our lives?

Like McPhee, I won’t be so bold to try to answer these questions myself. Nor do I particularly resent, as a tax-paying resident of Los Angeles County, the notion that a certain portion of my hard-earned tax dollars are being used to support someone else’s lifestyle full of serene city and mountain views. After all, my own lifestyle is deeply dependent upon the implicit generosity of fellow tax payers, and the risks that my family and I bear within our own local neighborhood are different, but not necessarily less, than those faced by the Genofiles and the rest of the county’s residents. This is not to suggest that society is structured equally—far from it. But it does seem to me that of all the arguments one might raise to question the wisdom of life in a place like Pinecrest, the selfish, miserly, myopic argument about keeping one’s tax dollars for themselves is by far the least compelling.


Pete Morris has been a full-time faculty member teaching Geography at Santa Monica College since 2000. After spending his earlier childhood in multiple U.S. states, he moved to Southern California with his family as a middle schooler in 1978—coincidentally the same year the Genofiles‘ home was nearly swallowed by the San Gabriel Mountains.

High-resolution version of all of my original images above, as well as a few others from the same day trip, are available via my Flickr site. If you are interested in reading additional reflections on metropolitan Southern California’s defenses against its eroding mountain backdrop, see the Friends of the Pleistocene’s much more extensive tour of the region’s debris basins. And if you are in L.A. and have the time and energy, you may wish to walk (or bike) the 10.6-mile tour at the “Top of the City of Los Angeles” that accompanied the Center for Land Use Interpretation’s 2006 exhibit, “Dissipation and Disintegration: Antennas and Debris Basins in the San Gabriel Mountains.”