Are we prepared for another earthquake? Are City officials doing as much as possible to prevent damage to buildings and loss of life? Senior Editor Wes Starratt looks into the matter and reports disquieting news.
As we approach 5:05 a.m. on the 18th of April, 99 years since the Great Quake of 1906, we ask, “Will San Francisco Have Another 1906 Earthquake?” The answer is definitely “Yes.” Is the City prepared for a major earthquake? Unfortunately, the answer must be “No.” Can the City develop a plan to save lives and reduce property damage? That answer is “Yes,” but not if it is blocked by political forces within the City! So, does rent control play a major role in the political opposition? “Hugely,” according to one advisory board member.
This is the Story of How and Why San Francisco’s Community Action Plan for Seismic Safety Hit a Political Roadblock and the Strenuous Efforts Being Made to Get it Back on Track
By Wes Starratt, PE, Senior Editor
Published: March, 2005
San Francisco is a unique city with a unique set of problems. Not only is it situated on a peninsula surrounded on three sides by water, but the city’s downtown is equidistant from two of North America’s most active faults: the San Andreas, some 10 miles west of the Financial District, and the Hayward Fault, some 10 miles to the east along the East Bay foothills. Furthermore, much of the city is built on sand, bay mud, and landfill, all of which are subject to liquefaction during a major earthquake.
According to the US Geological Survey, there is a 62 percent probability of at least one magnitude 6.7 or greater earthquake in the Bay Area before 2032 (see accompanying figure). The Bay Area experienced a large quake in 1838 and another large one in 1868. It was followed by the big one in 1906, which appears to have relieved some of the stress on the San Andreas Fault. So, another large quake on the San Andreas did not occur for 83 years, and then it occurred near Santa Cruz. Even though that quake, called the Loma Prieta, was of short duration and not on the magnitude of the 1906 earthquake, it still caused the collapse of a number of San Francisco apartment buildings built on the filled soil of the Marina district.
Consequently, San Francisco can definitely expect another major earthquake; the only question is when. Will it be today, tomorrow, next week, next year, or ten or more years from now? There is nothing that can be done to stop it, but we can be ready for it. Let’s turn to the key question:
Is the City Prepared for a Major Earthquake?
That answer is negative. To get a more precise response, we talked with the city’s chief building inspector, Laurence Kornfield. He explained that, “A couple of years ago, we asked the Structural Engineers Association of Northern California (SEAONC) to help us make some code changes. The Mayor (Willie Brown) advised us that we needed a larger review process, and this led us into the Community Action Plan for Seismic Safety, or CAPSS. A consultant was hired, and Kornfield gathered together a group of distinguished structural engineers, architects, seismologists, planners, and other professionals to contribute their time and come up with recommendations.
CAPSS is a large, multipart program that will take several years to complete. Daniel Shapiro, an eminent structural engineer who has practiced engineering for more than 50 years and is a former chairman of the California Seismic Safety Commission, was selected to head CAPSS Citizen Advisory Committee. At the same time, SEAONC formed a Blue Ribbon Committee, headed by another prominent structural engineer, Patrick Buscovich, to assist CAPSS. Members of those powerhouses of knowledge were asked to contribute their time and understanding to the development of an earthquake survival plan for the city.
Committee members noted that “San Francisco’s CAPSS program is unique among cities in the United States,” and stressed that “every city in earthquake country should have such a program.” Fortunately, the city could draw more than $750,000 for CAPSS from the “Strong Motion Instrumentation Program,” or SMIP fund, which is handled by the state and derives its income from building permit fees.
The first phase of the CAPSS program was a vulnerability study or impact assessment. It included an examination of the entire stock of privately-owned buildings in the city (public buildings excluded) to assess the potential damage that could be caused by earthquakes of magnitudes 7.9 (the 1906 Earthquake), 7.2 and 6.5 on the San Andreas Fault offshore at Lake Merced, and a magnitude 6.9 quake on the Hayward Fault in Oakland and Berkeley. A well-known local engineering research and development organization, Applied Technology Council (ATC), was contracted to do the research and prepare the report, with assistance to be provided by various city departments, the US Geological Survey, and the California Geological Survey. A computer model was created and, with the help of experts, was subjected to a range of earthquake scenarios. This vulnerability analysis is now virtually complete.
According to John Paxton, a San Francisco real estate consultant and a member of the CAPSS Advisory Committee, “The important next step is to use this information as a basis for enacting code changes for strengthening buildings and providing post disaster response.”
The second phase of CAPSS would be the establishment of building strengthening procedures that could be done prior to an earthquake, and repair requirements that would follow an earthquake.
The third and final phase would be the development of a long-term mitigation plan for the city, which would include mandatory and voluntary measures, incentives, and an education plan.
Finally, the CAPSS plan would have to be approved by the City’s Board of Supervisors, then the State’s Office of Emergency Services and the Federal Emergency Management Administration (FEMA) in order to be eligible for federal funding disaster assistance.
How Much Damage?
Of a total value of $104 billion in privately-owned buildings in San Francisco, CAPSS first-phase assessment showed that 28 percent could be destroyed by the shaking caused by a1906-magnitude earthquake, much of it due to the collapse of “soft story” apartment buildings (as noted below). If fire is added to shaking, the loss could increase up to 43 percent in certain areas of the city, depending on the direction and velocity of the wind. That adds up to a total of almost 46,000 buildings totally damaged by shaking plus fire in the worst-case scenario. Population impacts would include hundreds killed and thousands requiring hospitalization, depending greatly on the time of day. These results indicate that earthquakes are a major threat to the safety and economic well-being of the city and its people. The objective of these CAPSS estimates was to provide decision makers with the basis for developing “a program designed to reduce these impacts.” But, it may also have set off an alarm bell among certain segments of the city.
The CAPSS Assessment Phase Report concluded, “San Francisco sustained a catastrophic earthquake in 1906 in which approximately 3,000 persons were killed and 28,000 buildings destroyed. Because most buildings in San Francisco were built of wood, as they are still built today, much of the destruction resulted from fires following the earthquake. Compared with 1906, San Francisco today has approximately twice the resident population, three times the daytime working population, and more than twice the total building floor area, yet many of its buildings date from before World War II and are still of wood construction.”
Unique City with a Unique Stock
of Buildings
Not only is the geography and the geology of San Francisco unique, but so too is its stock of buildings, as was revealed in the first phase of the CAPSS study.
Some of the city’s neighborhoods not only have the oldest buildings but also the highest population densities in the West. Along with New York City, San Francisco is one of the few urban areas in the country were the vast majority of its residents live in apartments or other rental units. Most of those apartments are not only rent controlled but are wooden structures, built before World War II, some possibly rotting and providing food for termites. So, in this beautiful city, most San Franciscans live in rent-controlled apartments located in old, wooden buildings, many of which will not withstand the next great earthquake.
There is something else about these old buildings that is of considerable concern. Many of them have a soft first story; that is, they have ground-floor parking garages or corner stores on the first floor that lack the horizontal (lateral) bracing needed to withstand the horizontal acceleration caused by an earthquake. It was these types of apartment buildings that collapsed (or “pancaked”) in the Marina District during the moderate 1989 Loma Prieta Earthquake. Damage was centered in the Marina because the filled ground there magnified the ground motion caused by the earthquake. Throughout the city, there are thousands of these types of apartment buildings that would collapse in a stronger earthquake.
Another factor that was highlighted during the first phase of the CAPSS study was the high percentage of San Francisco apartments that are rent controlled, especially in the older wooden buildings that are most vulnerable to earthquake damage. Thus, the oldest and poorest of the city’s residents are probably the most vulnerable to earthquake damage.
Political Dissent “Boils Over” and Brings CAPSS to a Halt
For this reason, the CAPSS study is not without political controversy between the city’s “haves and the have-nots.” Upgrading old buildings costs money. Owners of rent-controlled apartment buildings have little means of passing along the cost of seismic upgrading and thus lack a monetary incentive for upgrading their buildings. In addition, many building owners would undoubtedly be reluctant to have their buildings identified as being seismically vulnerable. In reality, owners of rent-controlled buildings have zero incentive to mitigate or retrofit their buildings. So, the rent control issue figures hugely into the CAPSS program (according to one committee member).
Furthermore, moderate earthquake damage to rent-controlled buildings could serve as a reason for rebuilding and turning structures into a condominiums, since new construction is not subject to rent control. The bottom line is that not everyone in San Francisco is enthusiastic about the CAPSS study, and political pressure has grown.
With CAPSS first phase virtually completed, that political pressure boiled over, and suddenly the city’s Buildings Inspection Commission brought all work on CAPSS to a halt with the excuse that the program was running out of funding. That was not the case, according to CAPSS Advisory Committee chairman Daniel Shapiro. CAPSS collapsed because of politics. The money is there. The program is not running out of funding, and the SMIP fund, which can be used for the CAPSS program and other similar programs, still has at least $250,000 and is growing. Furthermore, all work for CAPSS has been paid to date.
Nevertheless, the Building Inspection Commission killed the CAPSS program, and there never was a final meeting of the Advisory Committee.
CAPSS committee member Paxton commented, “Many of us are pulling in different directions to get CAPSS reinstated one way or another. But, we are all very frustrated at our lack of success!” Committee member Mary Lou Zoback, Regional Coordinator of the US Geological Survey’s Earthquake Hazard Program in northern California, pointed to the importance of CAPSS, stressing that, “There are several hundred thousand people in San Francisco who might be homeless following a major earthquake, when modest retrofit could have kept them in their homes.”
Jim Chappel, who is head of the very influential organization San Francisco Planning & Urban Research Association (SPUR), stressed that, “The CAPSS study should be completed with all dispatch.” He made his feelings known at City Hall. At the same time, some CAPSS committee members have testified in Board of Supervisor’s hearings. The position of the mayor is not clear on this issue, however, and his office did not respond to our telephone calls. One might wonder if, with the upcoming Centennial of the 1906 Earthquake and the accompanying worldwide publicity focused on San Francisco, the city might not be hesitant to reveal how ill-prepared the city is to a second 1906 disaster.
Meantime, political rumblings continue at City Hall. Two vacancies have occurred on the seven-member Building Inspection Commission, and the mayor has appointed Ephraim Hirsch, a well-known structural engineer who reportedly favors the CAPSS program, and city architect Frank Lee. The post of the Director of Building Inspection has been vacant for some time, with only the Commission, not the mayor, able to appoint a person to that position. That promises to be the next battleground for CAPSS.
There is a ray of hope, however. ATC has volunteered to complete its work on the Vulnerability Phase of the CAPSS study and publish it at its own expense on or before the 99th Anniversary of the 1906 Earthquake on April 18th. Building inspector Kornfield advised us that, “We will cooperate with them.” Hopefully, the widespread dissemination of the CAPSS information on the vulnerability of San Francisco in the next great earthquake will shake up not only the Building Inspection Commission but City Hall as well.
Kornfield commented that, “Both the mayor’s office and the Office of Emergency Services (OES) are interested in hazard mitigation. So, I would be hopeful that they would pick up this and complete the work or some elements of it. There remains a lot of work to do. I would like to see the City move forward in hazard mitigation, and I actually think that we will through OES or the mayor’s office. The mayor has expressed an interest in seeing CAPSS completed and has asked the City’s OES and other people to look into it. He is very committed because of the 1906 Earthquake Centennial next year.”
In any case, the results of the CAPSS vulnerability assessment are very clear. According to Zoback, “Damage to housing in San Francisco is likely to be substantial in future quakes, but this is a fixable problem. The first step is to use the protected SMIP funds sitting in the City budget to complete the CAPSS program.”
The bottom line remains that the City of San Francisco is highly vulnerable to damage from another earthquake, and the most vulnerable buildings are the City’s old wood-frame apartment buildings that are largely rent controlled. The most vulnerable of the City’s citizens are the residents of those apartment buildings, many of which would be damaged or destroyed by the earthquake and fire that could easily follow. Furthermore, a major earthquake would transform San Francisco’s population from residents of rent-controlled apartments to residents of higher-priced condominiums, with those unable to pay the price being forced to leave the City. Thus, without the CAPSS program, a major earthquake could totally transform the City and its population from what it is today.
Unfortunately, it has become obvious in San Francisco that some groups are more interested in leaving their buildings as they are rather than making an effort to reduce the loss of life and property that will occur when the “Big One” strikes. As one CAPSS committee member stated, “Perhaps the politicians don’t want it to be known how vulnerable the City is to a potential disaster!”
