Monday, November 25, 2019

[San Francisco City and County] Thirty years after Loma Prieta, is San Francisco ready for the next ‘big one?’

Blog note: this article references a grand jury report.
Bay Area residents breathed a sigh of relief this week after a series of earthquakes that rocked the region proved not to be “the big one.”
Striking just days before the 30th anniversary of the Loma Prieta earthquake — a magnitude 6.9 temblor that killed 63 people on October 17, 1989 — the string of seismic events beginning Monday night provided a reminder of the very real threat earthquakes present for the region.
That threat is amplified by the Hayward Fault, which seismologists say is due for a major quake in the next 30 years. Overall, there is a 72 percent chance of a magnitude 6.7 or greater earthquake striking the Bay Area by 2043, according to the U.S. Geological Survey. Risk Management Solutions, a global risk modeling and analytics firm, has calculated that the Bay Area would suffer $38 billion in economic losses if a quake identical to Loma Prieta were to occur today in the same location.
Though the Loma Prieta’s epicenter was in the Santa Cruz Mountains, the entire Bay Area felt its effects. In San Francisco, the worst damage occurred in the Marina District, where four people died, buildings caught fire, others collapsed, and more than 60 structures were condemned in the aftermath.
The devastation led to the development of numerous earthquake preparedness projects and billions in infrastructure investments.
Still, the question remains: 30 years later, are San Francisco and its residents more prepared for the next “big one?”
Department of Building Inspection Director Tom Hui thinks so.
Hui is celebrating a 30th anniversary of his own this week. He began his public service career in San Francisco with the Public Utilities Commission’s Engineering Bureau the day before the Loma Prieta earthquake.
The things Hui and other city officials learned by inspecting buildings and infrastructure in the Marina District in the days after the quake paved the way for numerous ordinances and programs in the following years, some of which are still in place today.
“I can say we are better prepared now compared to 30 years ago,” he said.
One ongoing program Hui considers a top priority is the soft story retrofit program, which began in 2013. Soft-story buildings are older, wood-frame structures with large open areas on the bottom floor, often used for parking or commercial space. The lack of walls or framing to help support the building on the bottom floor present a high risk to the property and its occupants in the event of an earthquake.
As Hui and other officials discovered, many of the buildings destroyed and condemned in the Marina District after Loma Prieta met this description. Further surveys found such soft story structures were common in the Mission, Western Addition, Richmond and North Beach districts.
Now, the soft story retrofit program is 65 percent complete, according to Hui. Buildings in the fourth and final tier of the program are supposed to have permits in place for seismic retrofits by Sept. 15, 2020.
While 1,052 buildings in the third tier are still listed as non-compliant a month after their Sept. 15, 2019 deadline, Hui said his department is in contact with the owners, aware of their reasons for delay and confident the retrofits will be completed.
“We know the reasons and we are trying to help them,” he said. “We try to push them. We don’t want to just only punish them. We encourage them to complete their work.”
Another area of concern for DBI is addressing the seismic safety of seven private schools, which are working closely with the department to retrofit their campuses, he said.
However, many buildings in the city are in far better shape to withstand a major temblor because they have been built to modern building codes.
From improved building codes and infrastructure to community engagement and training, the City has every intent to continue its efforts and investments in earthquake preparedness, Hui said, calling this week’s shake-up “a wake-up call to remind us [an earthquake] can come at any time.”
‘Critical investments’
San Francisco has made “critical investments” in infrastructure and emergency response that have improved its ability to plan, respond and recover from a major earthquake, according to Francis Zamora, director of external affairs for the Department of Emergency Management.
“The role of DEM during any emergency is to coordinate resources and promote problem-solving in an organized, focused and systematic setting,” Zamora said. “This happens in the City’s Emergency Operations Center (EOC, which is one big room, so a lot of different organizations can be together while working toward fixing, restoring and supporting city services.”
During Loma Prieta, the City did not have a functioning or active EOC, he said. Today, the EOC is active seven days a week and supports special events like Bay to Breakers, Pride and Fleet Week.
Despite such investments, other areas are sorely lacking. According to a civil grand jury report issued earlier this year, roughly one-third of the City’s developed area is not covered by San Francisco’s high-pressure firefighting water system, the Auxiliary Water Supply System (AWSS), which was installed in 1913 in response to the fires caused by the Great Earthquake of 1906.
The report raised concerns about the lack of coverage for neighborhoods like the Sunset, Richmond and Bayview, as reported in The Examiner last month, leaving residents vulnerable to blazes after a major earthquake.
The San Francisco Public Utilities Commission and Fire Department are developing plans for a potable Emergency Firefighting Water System for the Western neighborhoods that is likely to include over 14 miles of new pipelines and two pump stations, according to the article.
“But at the City’s current pace it will take approximately 35 years or more to build out a [high-pressure] AWSS pipeline system that serves all neighborhoods, including the southern portions of the City,” the report said. “The City does not have a plan with a firm timeline for completion of this work or firm plans to fund all the work that needs to be done.”
The San Francisco Fire Department did not reply to requests for comment by press time.
Another glaring risk comes in the form of liquefaction, which occurs when loosely packed, waterlogged soil loses its strength during a seismological event, essentially acting as a fluid and not a solid and imperiling buildings and their occupants. Most neighborhoods in San Francisco that abut the Bay, from the Marina to the Bayview and also parts of SFO, were built on landfill and subject to liquefaction.
Zamora said the City’s investments will not only save lives — they will save money.
The Institute of Building Sciences finds that $6 are saved for every dollar invested in mitigation activities to reduce risk and disaster losses, Zamora said.
“San Francisco has invested $12 billion with another $8 billion in the pipeline to make our critical lifelines more resilient,” he said. “This means San Francisco can potentially save up to $120 billion in losses from a catastrophic earthquake.”
In the past decade alone, Zamora said San Francisco has tested plans to shelter and care for displaced residents; distribute water, food and other commodities; deploy medical personnel and resources; bring in emergency fuel for critical facilities; manage and clear disaster debris; open port facilities and establish staging areas for state, federal and private sector partners to bring in disaster relief supplies.
‘Continuing journey’
Stringent building codes, established offices and emergency response-trained personnel are only half the battle. How prepared San Francisco is for the “big one” is just as much in the hands of its residents, Zamora said.
“Community preparedness is a continuing journey, not a destination,” he said. “This is why San Francisco invests in programs that focus on building preparedness through community.”
The Neighborhood Emergency Response Team (NERT) provides free emergency preparedness and response training from the SFFD. NERT has trained more than 30,000 residents to take care of themselves, their families and their community since Loma Prieta, Zamora said.
Another DEM program, SF72, focuses on community connections to get people prepared. The program’s name references the 72-hour survival kits city residents are urged to make to survive for three days should lifeline services be interrupted following a disaster.
“One of the highlights of SF72 is our partnership with the San Francisco Unified School District,” Zamora said. “In 2018, we launched a semester-long earthquake and emergency preparedness course for all seventh graders in our public schools. This means up to 4,000 students a year are learning about earthquakes and how to prepare for them.”
Then there’s the Neighborhood Empowerment Network, which works with individual neighborhoods to create disaster preparedness action plans tailored to the specific needs of each community. NEN is hosting a Community Preparedness Fair Thursday on the west end of the Marina Green from 3-6 p.m. for the 30th anniversary of Loma Prieta.
Richard Allen, director of the Berkeley Seismological Lab, said the San Andreas Fault, on which the Loma Prieta quake occurred, and the Hayward Fault, are the two faults most likely to devastate the Bay Area. The question is not if but when the next major quake will occur, he said.
Since the 1989 Loma Prieta earthquake, a dense and robust network of instruments collecting data across the state and countless observations made by researchers have led to improved public policy and building codes, he said.
“If you’re in a new building, you’re in pretty good shape for withstanding an earthquake,” Allen said.
MyShake, UC Berkeley’s citizen science app designed to build a global earthquake early warning network, is slated to offer early detection alerts later this fall, he said.
“We can do earthquake early warnings anywhere there’s smartphones,” he said, “which is everywhere.”
October 16, 2019
San Francisco Examiner
By Cody McFarland


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