Quake devastated Santa Barbara 100 years ago. What can it teach us?

One hundred years ago today, downtown Santa Barbara was devastated by an earthquake centered just offshore.

The main commercial district, State Street, was in ruins. Some buildings completely collapsed — the vulnerability in their designs laid bare by the power of Mother Nature. Around a dozen people died.

Yet, despite the destruction, the great Santa Barbara earthquake remains relatively obscure, seismically speaking, even in a state notorious for its shaking.

There are a number of reasons why, ranging from the comparatively low death toll to concerted efforts by contemporary civic boosters and business interests to downplay the extent of the damage.

But in a state where the next “Big One” is an always-looming threat, lessons learned from the Santa Barbara quake should still resonate — even 100 years later, experts say.

Structural engineers, for instance, have long considered brick buildings to be one of the deadliest types of structures in an earthquake. And the Santa Barbara temblor revealed just how dangerous brick buildings built in that era could be.

Yet for decades, little was done to force brick buildings around California to be retrofitted — inaction that had deadly consequences, from the 1933 Long Beach earthquake all the way through to the 2003 San Simeon earthquake, when two women were killed as they fled a brick building in Paso Robles that was originally built in the late 1800s, according to seismologist Lucy Jones, a Caltech research associate.

Workers sift through a collapsed brick building.

One of the biggest lessons, Jones said, is that “we are afraid to tell people what to do with their own property, so we’ve always sort of gone for the minimum.” That’s how a building managed to go without a critical earthquake retrofit for more than a century before its brick walls collapsed in 2003.

Many cities eventually took action to address these vulnerabilities through mandatory retrofit ordinances — Los Angeles in 1981, Santa Barbara around 1990, and San Francisco in 1992, the last of which acted after car commuters were crushed to death when a brick wall collapsed during the 1989 Loma Prieta earthquake.

Wreckage following an earthquake in San Francisco.

But other Southern California cities still haven’t acted to require unretrofitted brick buildings be fixed or torn down — including many in the Inland Empire, home to the infamous San Andreas fault.

Many cities have also not acted on requiring retrofits of other types of potentially vulnerable buildings, including those that have certain flaws to their concrete or steel frames.

In Santa Barbara, for instance, there isn’t a law requiring seismic retrofit of apartment buildings with a flimsy ground floor — often held up above a carport or garage. These “soft-story” buildings, whose vulnerabilities are well known, are the target of mandatory retrofit laws in cities such as San Francisco and Los Angeles.

Soft story apartments can collapse because the skinny poles holding up the carports can snap when shaken.

“I know it’s been talked about in Santa Barbara, but nothing has ever come of it,” said structural engineer Sage Shingle, a member of the Structural Engineers Assn. of Southern California and a principal at T&S Structural. Not requiring these buildings to be strengthened, “of course, it makes Santa Barbara more vulnerable than it could be,” he said.

A century ago, Santa Barbara also saw significant damage to single-family homes that weren’t braced and bolted down and slid off their foundations — a structural flaw that still exists for many homeowners today. (A state program offers grants to entice homeowners to resolve the issue.)

But the most vivid damage from the 1925 earthquake was the collapse of brick and stone along Santa Barbara’s State Street.

A damaged hotel after the 1925 Santa Barbara earthquake.

The four-story Hotel Californian, which had opened about a week before the earthquake, saw its exterior brick walls “peeled away from the wood floors,” Shingle said.

In Santa Barbara, “there were a couple places where just the facade falling onto the sidewalk actually killed people,” said architect Greg Rech, president of the Architectural Foundation of Santa Barbara.

California learned the dangers of brick construction when a major earthquake struck Long Beach in 1933.

The historic Arlington Hotel was also severely damaged in the 1925 earthquake. Opened in 1911 to replace a predecessor that burned down in 1909, it was rebuilt with a water tank as storage for future firefighting efforts, Shingle said. But when the earthquake’s shaking hit the weight of that tank, “the mass of it just pulled the building apart right there and collapsed that area of the building,” Shingle said. Two hotel guests died.

A century ago, the science of earthquakes was still in its infancy. It might be hard to imagine today, but prior to 1925, “there was still a debate at that time about how severe earthquake hazard was in Southern California, and Los Angeles, in particular,” said Susan Hough, a seismologist with the U.S. Geological Survey.

“There were two camps: One was arguing that there was significant earthquake hazard in the Los Angeles area. And another camp was arguing that there were earthquakes, but that hazard was only moderate,” Hough said.

A damaged hotel following the 1925 Santa Barbara earthquake.

The 1925 earthquake didn’t settle the debate, Hough said. Estimated to be somewhere between magnitude 6.5 and 6.8, the Santa Barbara temblor came the same year as an earthquake in Quebec, Canada — now estimated to be magnitude 6.2. But the reach of the Quebec earthquake covered a wider area, which we now understand is because the rocks in eastern North America are older, and allow seismic waves to travel more effectively than in California.

But at the time, the smaller geographical reach of the shaking around Santa Barbara led some to argue that, essentially, earthquakes were a bigger problem for Quebec than Southern California. The argument was, “yeah, you have earthquakes in California, but the effects aren’t as wide,” Hough said.

“In terms of public awareness and risk reduction, 1925 didn’t move the needle as much as it might have,” Hough said.

Additionally, “there was some effort by the business interests to downplay the hazard,” Hough said. There was “the idea that nothing good would come out of scaring people.”

By 1906, it was accepted that the San Francisco Bay Area had a high earthquake hazard, but the view among some in the Los Angeles area was different. The Inglewood earthquake of 1920 — estimated at a magnitude 4.9 with an epicenter in Santa Monica Bay — gave seismic minimizers another opportunity to suggest “that moderate earthquakes on local faults would cause, at most, minor, localized damage,” the USGS says.

“The sense was, ‘Yeah, we have earthquakes. They’re a nuisance, but they don’t do any damage,’” Hough said. “They mapped faults in the L.A. area, but they argued that they weren’t active.”

And scientists hadn’t yet developed the theory of plate tectonics, which we now know explains why California is particularly vulnerable to earthquakes.

Still, it wasn’t as if everyone was completely in denial about the dangers. People were aware of the risk of fires following the 1906 San Francisco earthquake and a 1923 magnitude 8 earthquake and firestorm that devastated Tokyo and Yokohama, causing an astonishing 142,800 deaths, according to the USGS.

In the first moments after the 1925 earthquake, “there were three men who turned off the gas, the water and the electricity. So we didn’t have the fires,” said Santa Barbara historian Betsy J. Green.

The earthquake did prompt Santa Barbara to adopt codes citing earthquake safety related to construction of new buildings — the first a local government in California had ordered, according to the Blume Earthquake Engineering Center at Stanford University.

More action was taken after the 1933 Long Beach earthquake, which resulted in 120 deaths and shocked Californians after 70 schools were destroyed — meaning the number of the dead or injured could’ve been in the thousands had the earthquake hit during school hours, according to the California Geological Survey.

The state Field Act required seismic safety standards on newly built public schools. And the state Riley Act, also passed in 1933, required California local governments to establish a building department and inspect new construction.

But it would take until the 1960s before California codes for new buildings became more uniform among local governments, according to the university.

As a decisive moment in Santa Barbara’s history, the earthquake also offered the opportunity to reshape its look. Even before the earthquake, there were urban reformers promoting a consistent Spanish Colonial Revival architecture style to be used across the city — in which the walls are white, on a rough stucco; there are a lot of arches; and the roofs are generally red tile, with a lot of the trim on windows and doors in a muted blue-green color, Green said.

A wealthy resident, Bernhard Hoffmann, not only bought and restored the historic adobe Casa de la Guerra downtown, Rech said, but bought property next to it and built a complex of shops called El Paseo.

“The idea was that they were trying to create the Street of Spain … Santa Barbara was a tourist town even back at that time, and they really recognized that they needed to differentiate themselves from Los Angeles or San Francisco that both had a lot of Victorian architecture,” Rech said.

The local city hall was also built in this style, as was the high school, Rech said.

Then the earthquake happened, and officials decided to make the Spanish Colonial Revival style mandatory in the downtown area. Some today may grouse about the rules, “but it keeps Santa Barbara looking like Santa Barbara, and not Ventura or Goleta,” Green said.

(The effort, however, had the effect of displacing the city’s old Chinatown, according to the Santa Barbara Trust for Historic Preservation.)

The earthquake also severely damaged the city’s old Greek Revival style courthouse, built in the late 1800s, breaking a column and collapsing part of the jail. The county approved a Spanish Colonial Revival-style replacement, funded in part by a bond, with cost overruns paid for by taxes on oil extraction in the county, said Bob Dickey, a docent for the Santa Barbara County Courthouse.

The courthouse is now considered one of the most picturesque places to get married in a municipal county building in California.

A key aspect to Santa Barbara’s recovery was that, even a century ago, it had developed itself as a tourist spot for the wealthy, and there were a number of powerful and influential people who were instrumental in sending capital and loans for the rebuilding effort, according to Green.

“There was a lot of money here,” Green said.

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