Seismologists say that in the not too distant future, San Francisco will suffer a devastating earthquake that could potentially kill thousands and billions in damage.
The United States Geological Survey predicts there is a 51 percent chance that a magnitude 7 earthquake will occur within the next three decades and release energy equivalent to about 1,000 atomic bombs.
A tremor of this magnitude would, according to government models, ruin buildings, cut power and vital communications, and cause huge wildfires.
Experts have laid bare the ongoing effort to contain such a disaster, but warned there is only so much that can be done to prepare.
A 2021 report looked at the effects of an earthquake on the Hayward Fault, which runs through the heart of San Francisco Bay.
A heat map shows which areas would suffer the highest “tremor intensity” if an earthquake occurred on the Hayward Fault, which runs through the heart of the San Francisco Bay Area. USGS seismologists say there is a 51 percent chance of such a tremor occurring within the next 30 years
The Hayward Fault runs through the heart of the Bay Area, so a major earthquake would be catastrophic for San Francisco
Seismologist Lucy Jones said, “There’s a 100% chance of this earthquake if you give me enough time.” The pictured San Francisco was built on the Hayward Fault, which experiences a devastating earthquake about every 110 to 220 years
USGS researcher Anne Wein, a co-lead on the HayWired scenario, said the intent of the project is “to have an earthquake without having one” so researchers can find the most likely outcome — and the best mitigation tactics can.
Seismologist Lucy Jones said: “The probability of this earthquake is 100% if you give me enough time.”
Seismological engineering expert Keith Porter, who worked on the HayWired scenario, told USA Today “it could happen tomorrow,” adding ominously, “We don’t know when… [but] It will happen.’
Large earthquakes on the fault have historically occurred every 110 to 220 years. The last was 154 years ago.
THE LIKELIHOOD OF A DEVASTATING SHAKE IN LA OR SAN FRANCISCO
The United States Geological Survey has calculated the probability of a destructive earthquake hitting either Los Angeles or San Francisco in the next three decades.
Los Angeles area:
- 60% that a magnitude 6.7 earthquake will occur
- 46% that a magnitude 7 earthquake will occur
- 31% that a magnitude 7.5 earthquake will occur
San Francisco Bay area:
- 72% that a magnitude 6.7 earthquake will occur
- 51% that a magnitude 7 earthquake will occur
- 20% that a magnitude 7.5 earthquake will occur
The HayWired earthquake scenario, prepared by USGS experts, predicts 800 deaths and 16,000 nonfatal injuries [will] created solely by shaking”. More could be expected from the aftermath, such as further shaking, power outages and wildfires.
The total cost of destruction would be more than $82 billion.
In a grim prediction, 22,000 people could be trapped in elevators without backup power during the quake – with hundreds of people in danger of death as the overwhelmed emergency services struggle to respond.
Porter told USA Today, “That means people are dead in those elevators.”
Thousands more would have to be rescued from collapsed buildings.
A summary of HayWired modeling also warns:
- The average East Bay resident could be without a water supply for six weeks, some as long as six months;
- Older steel-frame office towers and new reinforced concrete residential buildings in downtown San Francisco and Oakland could be unusable for up to 10 months;
- About 450 major fires could cause residential and commercial loss equivalent to more than 52,000 single-family homes and nearly $30 billion in property damage (buildings and contents).
Experts say a combination of early warning systems and “fall, cover and hold” measures could prevent up to 1,500 nonfatal injuries out of an estimated 18,000 total nonfatal injuries from concussion and liquefaction hazards.
A major earthquake on the San Andreas Fault in California in 1906 was “one of the most significant earthquakes of all time”. This image shows people standing in the rubble of collapsed buildings on Mason Street and Ellis Street after the earthquake
A major earthquake on the San Andreas Fault in California in 1906 was “one of the most significant earthquakes of all time”. Pictured is Market Street with the Phelan Building in the foreground
A major earthquake on the San Andreas Fault in California in 1906 was “one of the most significant earthquakes of all time”. View from the southeast slope of Nob Hill towards blazing fires south of the market district after the 1906 earthquake
A 7.9 magnitude earthquake in 1906 that ruptured a 296-mile stretch of the San Andreas Fault is described by the USGS as “one of the most significant earthquakes of all time.”
The quake, which began at 5:12 a.m. on April 18, killed thousands, left more than half the population homeless and destroyed nearly 30,000 buildings.
The last major quake on the Hayward Fault occurred on October 21, 1868 and was “one of the most destructive in California history,” according to the USGS.
According to experts, to minimize the damage of a similar catastrophe today, fundamental infrastructure improvements are also required.
Some of San Francisco’s plumbing and building structures are aging and in need of modernization.
Building codes can also be improved to ensure new structures are more resilient.
Retrofitting elevator systems with backup power systems will also reduce the number of trapped people.
According to experts, to minimize the damage of a similar catastrophe today, fundamental infrastructure improvements are also required