California to get major quake within 30 years, experts say
April 28, 2008By Ryan Mac
The 5.6 magnitude earthquake that shook Stanford in the fall of 2007 may only be a taste of what’s to come, according to a recent U.S. Geological Survey (USGS) study.
In the report released this month, geologists announced predictions that all but guaranteed the occurrence of a major earthquake in California within the next 30 years.
The report, which places a 99 percent probability of a 6.7 magnitude quake occurring along some major fault line in California, confirmed earlier predictions and placed more accurate probabilities on seismic activity within certain areas of the state.
For California’s major metropolitan areas these numbers provide a reason for concern.
“The probability of a magnitude 6.7 or larger earthquake over the next 30 years striking the greater Los Angeles Area is 67 percent,” according to an Apr. 14 press release from the USGS. “In the San Francisco Bay Area it is 63 percent.”
Stanford Provost John Etchemendy Ph.D. ‘82 said he believed that the University has taken the right measures and developed a feasible plan to prepare for the worst.
“We are constantly assessing our earthquake preparedness, both in terms of building safety and in terms of response planning,” Etchemendy said. “We maintain stocks of emergency food and water on campus for use during an earthquake or other emergency. Recently, we decided to increase those stocks by about 60 percent, for added safety.”
Etchemendy also noted that Stanford has a thorough building review policy that is constantly being reevaluated to ensure that buildings are up to safety standards. Citing the precedent set after the 1989 Loma Prieta earthquake that shook the Bay Area, he stated that many buildings have been reinforced to protect from major damage.
“Every building that posed a life-safety hazard to its occupants has now been seismically retrofitted — or, in some cases like the Old Chemistry building, closed,” the Provost said.
Such strict earthquake regulations are the reason behind Meyer Library’s demolishment by the year 2012.
“Our concern about Meyer library has more to do with its external safety than with the safety of its occupants,” Etchemendy said. “We feel that the tile roof overhangs are a potential risk. Since the remedies for this would be both extraordinarily expensive and unsightly, we have decided Meyer should be demolished.”
Still, even building safety cannot completely prevent the destruction by a potential earthquake.
“In a severe earthquake, many buildings on campus would suffer damage — that’s inevitable. But we do not believe there are any that would experience a serious structural failure,” Etchemendy stressed. “One can never reduce earthquake hazards to zero.”
Geophysics Professor Greg Beroza stated that regardless of the exact probabilities forecast by the study, anyone in the areas mentioned would be wise to heed these warnings.
“It’s difficult to assess accuracy in something like this,” Beroza said in an email to The Daily. “The bottom line is that living in either place, you had better be prepared for a large earthquake.”
Sandwiched between two major fault lines, the Northern San Andreas and the Hayward faults, Stanford remains at risk for seismic activity more violent than the fall 2007 quake. Though Stanford is not located in one of the most likely regions for a quake, the figures still place this campus at risk.
“The fault that is thought most likely to rupture in the San Francisco Bay Area is the Hayward fault (31 percent chance over the next 30 years), which last ruptured in a big earthquake in 1868,” Beroza wrote. “The San Andreas Fault is closer to Stanford, but it had a great deal of slip in 1906 and is thought to be less likely to be ready to rupture again. The report indicates a 21 percent chance for the northern San Andreas over the next 30 years.”
Ron Pomper ‘11, whose family experienced the magnitude 5.2 Illinois earthquake two weeks ago, voiced his concern regarding the University’s lack of emphasis on what the individual should do in case of such a disaster.
“I don’t think we’re that prepared because we haven’t really done anything to prepare,” Pomper said. “I feel that building safety and regulations are stressed heavily by campus authorities. [Regarding] individual safety and preparations, I don’t know if we would be ready for such a large scale disaster.”
Information on Stanford University’s earthquake plans or guidelines for individual preparation in case of such an event can be found at www.stanford.edu/dept/EHS/prod/general/erprep/plans/index.html.