By Annette Semerdjian
Years of pressure holding a slipping fault could relieve itself and set off a major earthquake for California, according to new research. Although California has multiple faults at risk of causing major damage, the San Andreas Fault is the biggest danger.
San Andreas Fault extends about 800 miles (1,300 kilometers) across California. For Southern California it lies directly through Palmdale, past San Bernardino, and through Palm Desert.
“The damage impacts of the scenario earthquake were estimated using both HAZUS-MH and expert opinion through 13 special studies and six expert panels, and fall into four categories: building damages, non-structural damages, damage to lifelines and infrastructure, and fire losses. The magnitude 7.8 ShakeOut earthquake is modeled to cause about 1,800 deaths and $213 billion of economic losses” according to The ShakeOut Scenario’s open-file report.
The San Andreas Fault has not relieved stress in years and human interference could also be a major trigger. According to the United States Geological Survey, “Wastewater from oil and gas production operations can be disposed of by injecting it into deep underground wells, below aquifers that provide drinking water,” which can induce earthquakes and may be the reason for earthquakes per a year increasing highly in 2009. This could also be a factor in the recent urgency around earthquakes.
Yet, certain parts of California face more danger than others. “Earthquakes pose especially high risks to the San Francisco Bay Area because of its close proximity to active faults with relatively frequent past movements,” according to California’s Public Utilities Commission. Softer soils compared to bedrock under cities are also more dangerous, as well as mountainous areas that are more susceptible to stronger shaking.
Although San Francisco faces bigger threats than Los Angeles, San Franciscans are slightly better prepared. With this in mind, the Los Angeles mayor’s office has taken steps within the last few years to prepare for earthquake damages. Los Angeles building officials started working on retro-lifting at-risk buildings this year. There was a particular danger for “dingbat” buildings, which have an open spot for parking with only two columns holding it up. These were popular in aesthetic in the 1950s and 1960s. Yet, these orders for reconstruction began this year and may not be ready for the earthquake danger ahead.
Also, Los Angeles Mayor Eric Garcetti is working on getting a better water system, which would be significantly helpful in an earthquake crisis. The effects of earthquakes are not only the damages of the earthquake itself, but also the aftershocks that may occur further damaging the city and its resources in a crisis if ill prepared.
Los Angeles County and the USGS are working on ways to improve technology and earthquake retrofitting. Congressman Adam Schiff has spearheaded an early warning system for earthquakes, which is currently under development.