by Paul R. Spitzzeri
I was not quite six years old and only moved to California from Chicago nine months prior, but I can definitely remember the Sylmar earthquake of early 1971. Though I lived in the Orange County suburb of Fountain Valley, the temblor was strong enough to scare the wits out of me.
For those of us living in earthquake-prone greater Los Angeles, there is a prevailing fear of the “Big One,” that 8.0 or larger shaker along the San Andreas Fault that would, if not separate our region from the continent, at least cause widespread damage, injury and death. In fact, there was not been a quake of that size since January 1857, when a massive shaking along the San Andreas hit. The region was sparsely populated so the loss of life and property damage was relatively light.
Yet, as we’ve come to learn over the decades, there are a great many smaller faults in our area and quakes that will register as less intense on the Richter scale can still create immense amounts of damage. One of these faults is the Newport-Inglewood, which runs along the coast. It was not known about until an estimate 5.0 shaker hit at 6:47 p.m. on this date in 1920, centered near Inglewood.
Today’s post highlights several snapshot photographs in the Homestead’s collection that document the damage done in that tremor, small as it appears to have been. Of course, destruction will always be greater if the epicenter is closer to the surface, if the geologic structure is conducive to more intensity of movement and, especially so nearly a century ago, if construction standards did not provide much protection in the event of a quake. All of these factors were involved in the 1920 earthquake.
The Los Angeles Times reported that there were two larger shocks, each lasting just a little more than ten seconds and four smaller aftershocks. Although the tremors were felt as far away as Ventura and Riverside, almost all of the damage took place in Inglewood, a booming town with lots of unreinforced brick buildings, specifically on Commercial Street, now La Brea Avenue. The Times stated:
Serious damage was done only in Inglewood, where walls of buildings fell into the streets, plate-glass windows were smashed, chimneys crumbled, telephones rendered useless and half the town left in darkness.
At least one person was reported to have died in Santa Monica, after Ella Sippy suffered a heart attack while climbing out of a car when the major shock hit. A man in Los Angeles was said to have been hurt when he fell off a ladder.
Back in Inglewood, a two-story hotel and commercial structure was most damaged and its 250-foot long front wall was completely gone. One couple, who resided in a unit on the second floor, was home at the time and Mrs. McDill found herself sitting on a rocker not more than a couple of feet from the edge of the building when the front collapsed. At the local substation of Southern California Edison, the resident operator and his wife were sound asleep in bed and, though, two of the side walls gave way, the couple were uninjured.
Accounts of losses suffered by other commercial structures were provided and it was said that most residences had some form of damage, often with brick chimneys. While many people were thrown to the ground, especially with the second major tremor, there were no reports of major injuries, much less death. A gas mainline ruptured, but no fires broke out, and the line was soon disconnected. The water system was disabled and residents were warned to conserve water. A guard of 100 men, overseen by the town marshal, were brought in to keep order and assist residents, some of whom slept outdoors for fear of more seismic activity.
The photos shown here give ample evidence of the destruction wrought in Inglewood and reported on in local papers. The hotel building, for example, and its neighbors showed significant amounts of damage. In one of the units a bed is shown just a couple of feet from the missing front. Workers were gathering up bricks from the destroyed wall and crowds gathered to survey the damage.
Another image shows missing fronts to two brick commercial structures, one housing a furniture store and a bank and the other a drug store, while a wooden front at the corner still stood, though wooden bracing was in place. Bricks are nearly stacked on the side of the road in front of the structures and piles of dirt in the middle of the street may indicate where the gas line was dug up for inspection and repair.
A third view shows the impressive Neoclassical First National Bank with apparent damage at its front entrance and along the roof, while more dirt is piled in the street in the foreground. Workers with sawhorses at the front and side of the structure are busy at work, as well.
There are about a dozen images in all in the museum’s holdings showing the destruction visited upon Inglewood by the quake, so these are just samples, but they attest to the significant effect of the temblor on the growing suburb.
Interestingly, a few years ago, a pair of scientists with the U.S. Geological Survey published a paper positing the idea that intensive oil drilling, which had been a major industry in the region for the prior twenty-five or so years, could have contributed significantly to seismic activity on the Newport-Inglewood fault, leading to the 1920 event. Notably, the fault had another major quake on it a little more than a dozen years later, when the larger and more destructive Long Beach earthquake of 1933 struck. That event led to the enactment of stricter building standards and other measures.
Later tremors, including the 1971 Sylmar quake and those at Whittier in 1987 and Northridge in 1994 continued to reveal vulnerabilities with structures, dams, freeway overpasses and other elements of our regional infrastructure. Concerns are still very strong about what future seismic activity has in store for our area.
Building a disaster proof/resistant city has always been perplexing. You can only take precautions against what you expect might happen. The biggest dangers to cities has always been fire. The history of almost every large city has at least one all consuming conflagration in its past.
When the easterners built the western cities, their thinking was to avoid fire (and heavy snow) so when possible they used brick. This material was thought to protect them. As shown in this image however brick is worst thing in an earthquake. The problem in building earthquake resistant structures is that due to their unpredictably, they are very difficult to study.
The 1868 Hayward quake came as a big surprise to those who lived here. Afterwards there were people who wanted to study what happened and learn more about WHY the ground shook, but there was also major pressure to prevent any and all earthquake research. The thinking was that if we knew why it happened, it would only reinforce that it could happen again and that would scare away settlers in the area.
It was only after the 1906 San Francisco calamity that scientists were allowed to study the cause and yes show the world that in California, they would reoccur. (what earthquake faults are and how they worked were unknown before 1906)
But how does ground shaking destroy buildings? It was originally thought that the seismic energy acted on a building just like a strong wind. A constant push from one direction. (so brick was still a good way to build) It was not until after the 1933 Long Beach quake that the consensus became that brick is not earthquake resistant. The multi directional shaking type forces were just not understood.
The codes were changed somewhat (Schools were improved because of the Field act) but change is always slow because you really dont know how a new type of construction will actually react until after the next shaker. Sylmar, Loma Preita, Northridge, Whittier after each one we are making progress.
Pictures like this play a big role in gaining a better understanding of how quake damage is caused leading to changes in building codes. Unfortunately it always takes another quake to show not only how far we have come, but also how much we dont know.
Sadly one thing we do know is that adobe is NOT a good building material in earthquake country and that is exactly what underlies the Homestead. Thinking positively, both structures have stood for hundred years or more and we will hope to someday see their bicentennial.
Thanks Jim for the comment and, yes, we’re hoping that the Workman House and La Casa Nueva will be with us for many years to come!