The ShakeOut Earthquake Scenario—A Story 

That Southern Californians Are Writing

U.S. Department of the Interior

U.S. Geological Survey

Circular 1324 

Jointly published as 

California Geological Survey Special Report 207
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The ShakeOut Earthquake Scenario—A Story 

That Southern Californians Are Writing 

By Suzanne Perry, Dale Cox, Lucile Jones, Richard Bernknopf, James Goltz, 

Kenneth Hudnut, Dennis Mileti, Daniel Ponti, Keith Porter, Michael Reichle, 

Hope Seligson, Kimberley Shoaf, Jerry Treiman, and Anne Wein

U.S. Department of the Interior

U.S. Geological Survey

Circular 1324 

Jointly published as

California Geological Survey Special Report 207
U.S. Department of the Interior

DIRK KEMPTHORNE, Secretary

U.S. Geological Survey

Mark D. Myers, Director

State of California 

ARNOLD SCHWARZENEGGER, Governor

The Resources Agency 

MIKE CHRISMAN, Secretary for Resources 

Department of Conservation 

Bridgett Luther, Director 

California Geological Survey 

John G. Parrish, Ph.D., State Geologist

U.S. Geological Survey, Reston, Virginia: 2008

This report and any updates to it are available online at: http://pubs.usgs.gov/circ/1324/

For product and ordering information: World Wide Web: http://www.usgs.gov/pubprod/, Telephone: 1-888-ASK-USGS

For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, 

natural hazards, and the environment: World Wide Web: http://www.usgs.gov/, Telephone: 1-888-ASK-USGS (1-888-275-8747)

Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any 

copyrighted material contained within this report.

Cataloging-in-Publication data are on file with the Library of Congress (URL http://www.loc.gov/).

Produced in the Western Region, Menlo Park, California

Manuscript approved for publication, April 21, 2008

Text edited by James W. Hendley II and Peter Stauffer

Layout and design by Judy Weathers

FRONT COVER—Ground motion for the ShakeOut Scenario earthquake 60 seconds after the southern San Andreas Fault first begins rupturing. Yellow shows 

the highest amplitudes of ground motion. (Simulation by Rob Graves of URS Corporation for the Southern California Earthquake Center on high-performance 

computers at the University of Southern California; image courtesy of Geoff Ely, University of California San Diego/San Diego Supercomputer Center.)

BACK COVER—Within the ShakeOut Scenario study area are many neighborhoods like this one, at severe risk from fire following earthquake. Here, tightly 

packed wood buildings will enable small fires to spread and merge into conflagrations that can burn dozens of blocks. Fire following earthquake can have 

devastating consequences, as tragically seen after the 1906 San Francisco, 1923 Tokyo, and 1995 Kobe earthquakes. It is a significant threat in urban areas 

of California and doubles the fatalities and economic losses in the hypothetical ShakeOut earthquake. (Google Earth image.)
iii

ShakeOut Scenario Coordinators:

Lucile Jones, USGS: Chief Scientist

Dale Cox, USGS: Project Manager

Suzanne Perry, USGS: Staff Scientist/Writer

Richard Bernknopf, USGS: Economics

James Goltz, Governor’s Office of Emergency Services: Emergency Response

Kenneth Hudnut, USGS: Earthquake Design

Dennis Mileti, California Seismic Safety Commission: Emergency Response

Daniel Ponti, USGS: Secondary Hazards

Keith Porter, University of Colorado: Physical Damages

Michael Reichle, California Geological Survey: Lifelines Special Studies

Hope Seligson, MMI Engineering: HAZUS Loss Estimations

Kimberley Shoaf, University of California Los Angeles: Health, Safety, Social, Cultural, and Institutional

Jerry Treiman, California Geological Survey: Lifelines Special Studies

Anne Wein, USGS: Economics

Contents

Introduction.....................................................................................................................................................1

The ShakeOut Scenario Is Not a Prediction .............................................................................................1

The ShakeOut Scenario Narrative..............................................................................................................5

How Do We Write the Ending? ..................................................................................................................15

Additional Information.................................................................................................................................16
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The ShakeOut Earthquake Scenario—A Story That 

Southern Californians Are Writing

By Suzanne Perry, Dale Cox, Lucile Jones, Richard Bernknopf, James Goltz, Kenneth Hudnut, Dennis Mileti, 

Daniel Ponti, Keith Porter, Michael Reichle, Hope Seligson, Kimberley Shoaf, Jerry Treiman, and Anne Wein

Introduction 

The question is not if but when southern 

California will be hit by a major earthquake— 

one so damaging that it will permanently change 

lives and livelihoods in the region. How severe 

the changes will be depends on the actions that 

individuals, schools, businesses, organizations, 

communities, and governments take to get ready. 

To help prepare for this event, scientists of the 

U.S. Geological Survey (USGS) have changed the 

way that earthquake scenarios are done, uniting 

a multidisciplinary team that spans an unprecedented number of specialties. The team includes 

the California Geological Survey, Southern California Earthquake Center, and nearly 200 other 

partners in government, academia, emergency 

response, and industry, working to understand the 

long-term impacts of an enormous earthquake on 

the complicated social and economic interactions 

that sustain southern California society. This project, the ShakeOut Scenario, has applied the best 

current scientific understanding to identify what 

can be done now to avoid an earthquake catastrophe. More information on the science behind this 

project will be available in The ShakeOut Scenario (USGS Open-File Report 2008-1150; 

http://pubs.usgs.gov/of/2008/1150/).

The “what if?” earthquake modeled in the 

ShakeOut Scenario is a magnitude 7.8 on the 

southern San Andreas Fault. Geologists selected 

the details of this hypothetical earthquake by 

considering the amount of stored strain on that 

part of the fault with the greatest risk of imminent rupture. From this, seismologists and computer scientists modeled the ground shaking that 

would occur in this earthquake. Engineers and 

other professionals used the shaking to produce 

a realistic picture of this earthquake’s damage 

to buildings, roads, pipelines, and other infrastructure. From these damages, social scientists 

projected casualties, emergency response, and the 

impact of the scenario earthquake on southern 

California’s economy and society. The earthquake, its damages, and resulting losses are one 

realistic outcome, deliberately not a worst-case 

scenario, rather one worth preparing for and mitigating against.

Decades of improving the life-safety requirements in building codes have greatly reduced the 

risk of death in earthquakes, yet southern California’s economic and social systems are still 

vulnerable to large-scale disruptions. Because of 

this, the ShakeOut Scenario earthquake would 

dramatically alter the nature of the southern California community. Fortunately, steps can be taken 

now that can change that outcome and repay any 

costs many times over. The ShakeOut Scenario 

is the first public product of the USGS MultiHazards Demonstration Project, created to show 

how hazards science can increase a community’s 

resiliency to natural disasters through improved 

planning, mitigation, and response.

The ShakeOut Scenario Is Not a 

Prediction

On November 13, 2008, the ShakeOut Scenario earthquake and projected damages will be 

used as a basis for public drills and emergency 
2 The ShakeOut Earthquake Scenario—A Story That Southern Californians Are Writing

response exercises, and so this hypothetical earthquake has been arbitrarily assigned a date, a time, 

a plausible collection of aftershocks, and even 

local weather conditions. Because it is a scenario 

for planning, it provides detailed numbers, including casualties, collapsed buildings, and business 

losses. Yet, the ShakeOut earthquake is not a 

prediction. Certainly, a large earthquake involving this part of the San Andreas Fault is highly 

probable. In fact, scientists have determined that 

this is the most likely source of a large earthquake 

in all of California (see Forecasting California’s 

Earthquakes—What Can We Expect in the Next 

30 Years?, U.S. Geological Survey Fact Sheet 

2008-3027; http://pubs.usgs.gov/fs/2008/3027/). 

When the next San Andreas Fault earthquake 

does happen, some things are inevitable—the 

fault rupture will break any road, track, or pipe 

that crosses it, and intense shaking will damage 

or destroy buildings that weren’t constructed to 

withstand it. The next earthquake will be different in details from the ShakeOut earthquake, and 

its total damages and losses will differ, because 

each earthquake produces its own patterns of 

shaking and damage. However, the widespread, 

regional effects will be similar, and so will the 

long-term social and economic impacts. Getting prepared for the ShakeOut earthquake will 

help southern Californians withstand other 

earthquakes of comparable size. If we take no 

additional actions for preparedness and mitigation, and the ShakeOut earthquake does occur, 

it will cause some 2,000 deaths, 50,000 injuries, 

$200 billion in damage, and severe, long-lasting 

disruption. These numbers can climb with each 

damaging aftershock.

San Andreas Fault

The Cajon Pass is one of five major “lifeline corridors” that are the veins and arteries through which 

economic life circulates in southern California. These lifeline corridors allow commuters, goods, 

telephone and Internet lines, electricity, water, gas, and fuels to move through the mountains that 

surround southern California. Because most of the corridors must cross the southern San Andreas 

Fault, future earthquakes are certain to sever the lifelines in one or more of these corridors and cause 

significant economic disruption by interrupting the movement of goods from the ports of Los Angeles 

and Long Beach. (USGS photo by Lucile Jones.)

LIFELINES CROSS THE FAULT
The ShakeOut Scenario Is Not a Prediction 3

The San Andreas Fault slices through southern California and produces earthquakes that shape 

and reshape the region. Unlike many other faults, the southern San Andreas Fault produces no 

small earthquakes. Its next earthquake will disrupt the complicated economic and social systems 

that define southern California and will affect everyone, including those living and working in 

communities relatively undamaged by the initial violent shaking.

MAP LOCATION

C A L I F O R N I A

N
These computer-generated snapshots show ground motions for the ShakeOut Scenario earthquake, in meters per second (m/s; 1 m/s is about 3.3 feeindicates higher amplitudes of ground motion. The snapshots show three points in time—30 (left), 60 (center), and 120 (right) seconds after the south(dashed white line) first begins rupturing at Bombay Beach, on the eastern shore of the Salton Sea. Note that some areas remain orange colored for indicating extended, intense shaking in some of the sedimentary basins of southern California. (Simulation by Rob Graves of URS Corporation for the So

Center on high-performance computers at the University of Southern California; images courtesy of Geoff Ely, University of California San Diego/San Diego S

THE EARTHQUAKE ADVANCES
The ShakeOut Scenario Narrative

Much like a movie script, the following fictional narrative will guide those participating in 

the ShakeOut Earthquake Scenario public drills and emergency response exercises on November 

13, 2008. More effectively than any statistics, this narrative describes what this magnitude 7.8 

earthquake would be like in southern California if no additional actions are taken for mitigation 

or preparedness.

November 13, 2008

Thursday 9:50 a.m. (... 10 minutes before the quake begins...)

By mid-morning on this workday, 200,000 commuters have made their way from 

Kern, Riverside, and San Bernardino Counties into the Los Angeles area. These drivers trade a lengthy commute for the lower cost of housing in fast-growing communities like Victorville and Lancaster, on the far side of 

the San Andreas Fault. Others cross the fault in the 

opposite direction, to employers in high desert communities. The commuters have joined 7.5 million other 

southern Californians in workplaces constructed of 

steel, concrete, brick, or wood. Of the many millions of 

homes and workplaces, only a fraction are covered by 

earthquake insurance. 

A steady flow of trains crosses the San Andreas Fault at 

multiple locations, moving goods between cargo ships at 

the Ports of Los Angeles and Long Beach and the rest of 

the country. Trucks are also on the move nonstop, carrying goods through narrow passes cut in the San Gabriel 

and San Bernardino Mountains. These “lifeline corridors” 

are the veins and arteries that sustain economic life 

in southern California. Sharing these passes with cars, 

buses, trucks, and trains are pipelines carrying natural gas and fuels; water conveyance 

tunnels, pipes, and aqueducts; electrical transmission towers and lines; and the telecommunications cables that connect people by phone and Internet—connecting banks and 

clients, suppliers and providers, buyers and sellers, friends and families, headquarters 

and field offices. Like the commuters, they all cross the San Andreas Fault. 

Thursday 9:52 a.m. (... 8 minutes before the quake begins ...)

The San Andreas Fault slices through California, 

marking the boundary between the Pacific and North 

American tectonic plates. Along this boundary, the 

plates try to slide past each other, but near the 

surface they are locked by friction and deform instead 

of moving, storing up strain energy. Eventually and 

suddenly, the friction will give way and the plates will 

slip, creating a powerful earthquake. This earthquake 

will rupture the Earth’s surface and release stored 

energy in seismic waves that travel out in all directions, 

shaking the ground as they go. On the southern San 

Andreas Fault, an earthquake rupture and energy 

release occur on average every 150 years—but the last 

time was more than 300 years ago.

The ShakeOut Scenario Narrative 5
The next earthquake is about to begin. It will not be the biggest earthquake that has 

ever occurred on the southern San Andreas Fault, but it will be big enough to change 

southern California markedly for untold years to come. It will wreak economic havoc on 

many who are unharmed by the initial shaking and damage.

Thursday 9:55 a.m. (...5 minutes before the quake begins...)

It is sunny with a light breeze. Fortunately, today there 

will be no Santa Ana winds. Throughout the region, cars 

flow to the pulse of traffic lights. Rush hour traffic has 

cleared, and the workday is well underway in offices, 

warehouses, factories, and stores. Many of the older 

buildings and even a few newer ones are constructed in 

ways that make them vulnerable to earthquake shaking. 

Schools are full of students, as well as furniture and 

equipment that will topple in a earthquake, and heavy 

objects that will become airborne. 

Thursday 10:00 a.m. (...the quake begins...)

The San Andreas Fault suddenly awakens at Bombay 

Beach, northeast of the Salton Sea, and the rupture 

shoots northwest along the fault at 2 miles per second, 

sending seismic energy waves out in all directions. In 

an instant, the ground on the two sides of the fault is offset nearly 44 feet, changing the political and geographic boundary between Imperial and Riverside Counties.

Thursday 10:00:30 a.m.

As the earthquake’s rupture front travels up the fault, it sends out seismic waves

that shake the ground, shifting emergency generators, overturning computers, cracking airport runways, and igniting fires. By now, the thick sediments 

of the Coachella Valley are resonating, with the 

earthquake waves bouncing between the rock walls of 

the valley’s edges. Strong shaking will continue here 

for nearly a minute. 

The life-safety provisions of California’s building 

codes have been improved over the years, and the 

many fairly new homes in the Coachella Valley suffer only minor damage. Yet every item inside these 

homes, if not secured, is heading to the floor. Shattered TVs and other home electronics create treacherous carpets of glass and cords. 

Many older buildings suffer structural damage. Many 

older concrete buildings quickly collapse, trapping occupants. The rupture front 

continues its advance to San Gorgonio Pass and dismantles the ten miles of Interstate 10 freeway that straddles the San Andreas Fault. The eastern part of Riverside County is now cut off from the western part.

Thursday 10:01:00 a.m.

Most people in Los Angeles and Ventura Counties are not yet aware of what is happening as the earthquake pounds the Coachella Valley and heads their way. By now 

6 The ShakeOut Earthquake Scenario—A Story That Southern Californians Are Writing
the first waves have crashed through the Cajon Pass, severing the I-15 freeway, 

bending rail lines, and derailing a train. Roads, previously throughgoing across the 

fault, now end abruptly and pick up again 15 feet to the right.The strong shaking 

also sends landslides across the rails and roads. Pipelines snap and electrical transmission lines fail. Spraying fuel ignites, causing an explosion.

Strong shaking begins to reverberate in the sedimentfilled basins of the Inland Empire. Old warehouse 

districts and historic downtowns are crumbling, and 

many of their old, unretrofitted buildings have trapped 

or killed the people inside. Many older concrete buildings have collapsed, and many older woodframe buildings 

have shifted off their foundations, breaking gas and 

water lines in the process.

The Coachella Valley is still shaking.

Thursday 10:01:30 a.m. 

Over geologic time, the motion of tectonic plates has 

pushed the mountains of southern California up, while 

fire, rain, and rivers have brought the mountains down, 

piece by piece, filling basins with sediments and creating low, flat areas. Like many 

cities, Los Angeles was built atop sediments. Some of the seismic waves now reach 

these sediments and find easy territory in which to move back and forth, shaking 

vigorously long after the waves fade elsewhere. Strong shaking will continue in Los 

Angeles for 55 seconds, to the shock of residents who remember the strong shaking 

during the 1994 Northridge earthquake, which lasted only 7 seconds. 

The seismic waves that reverberate in the sedimentary basins are big, long waves. Many buildings ride 

them like boats in choppy seas, but some are not so 

resistant. The prolonged, strong shaking heavily damages and sometimes collapses hundreds of old brick 

buildings, hundreds of older commercial and industrial 

concrete buildings, many woodframe buildings, and 

even a few, fairly new high-rise steel buildings. The 

building damage causes tens of thousands of injuries 

and hundreds of deaths, and strands many thousands 

of people without homes or jobs.

Buried in the sediments are the water and sewer pipes 

that maintain the cities. Many of these pipes crack 

when the earthquake waves deform the ground. 

In the newer houses, the primary damage is to contents. 

Kitchen floors have disappeared under heaps of cooking 

oil, syrup, flour, and smashed dishes, but there is no water in the taps to start cleaning.

Power is out so stoplights are dark and electric trains are suddenly immobilized. 

Buses, cars, and trucks become gridlocked, and many drivers will experience this 

earthquake as taillights for hours, to the horizon. Eventually, many will open their 

car doors and not look back as they begin the long walk home, perhaps envied only by 

people sitting in the dark, waiting to be rescued from stalled and stifling elevators.

The ShakeOut Scenario Narrative 7
8 The ShakeOut Earthquake Scenario—A Story That Southern Californians Are Writing

Thursday 10:02 a.m. (...2 minutes after the quake began...)

At last, the fault has stopped rupturing, but seismic waves continue to advance 

into Bakersfield, Oxnard, and Santa Barbara—here the shaking is just beginning.

Across southern California, the power is out. Emergency generators that have been 

secured against earthquake shaking are still functional and now kick on. The shaking 

has finally stopped in the Coachella Valley—but the aftershocks are just beginning. 

Throughout southern California in the next few 

months there will be tens of thousands of earthquake aftershocks large enough to feel. There will 

be dozens large enough to cause additional damage 

and to imperil victims and rescuers. Some of the 

aftershock damage will be to people’s psyches. Big 

earthquakes are traumatic, and each new bout of 

shaking increases stress, especially in children who 

are cut off from their families.

In the areas of strong shaking, many mobile homes 

have collapsed off supports, snapping water, gas and 

sewer lines, and blocking rescue routes. Mobile homes 

installed snugly in shallow pits, or braced for earthquakes, are still intact.

The State highway system has fared well. A $6 billion investment in seismic retrofitting has paid off, 

and the only highway deaths have been in crashes caused by intense earthquake 

shaking. However, the long duration of shaking has taken its toll on bridges and 

overpasses within local jurisdictions, where the retrofitting process is not completed, or not yet begun. 

No hospitals have seen complete collapses, but many hospital buildings are nonfunctional. Some hospital structures survived the shaking but must close due to nonstructural damage such as water pipes that break and flood. 

Thursday 10:05 a.m. (... 5 minutes after the quake began ...)

The U.S. Geological Survey posts preliminary information about the earthquake. Learning that the magnitude is 7.8, the world turns its attention to southern 

California. Locally, news helicopters take to the air to 

begin spot coverage of the devastation. With power 

out, residents turn to their radios or talk to those they 

meet in the streets, searching for any information.

Across the region, phone systems, including 

cellular and 911, are unusable, overwhelmed by the 

vast number of attempted calls. 

Thursday 10:30 a.m. (... 30 minutes after the 

quake began...)

Emergency operations centers are activating, 

and police, fire, and medical personnel shift into 
The ShakeOut Scenario Narrative 9

emergency response mode, focusing on localized incidents with any means 

available. They react quickly, according to their training and earthquake plans 

established in advance.

All over the region, a foreseeable tragedy unfolds. Buildings that engineers knew were 

going to perform badly, have performed badly. These are older buildings, constructed 

with little earthquake resistance. The experts have names for them—non-ductile reinforced concrete, tilt-up concrete, unreinforced masonry, 

soft-stories—and hundreds of these buildings have now 

followed their reputations into the dust. Thousands of 

other structures are still standing, but so gravely damaged that they can never be used again.

While the earth still shakes in places far from the 

earthquake’s origin, people in the earliest hit areas 

are beginning to confront damaged buildings and to 

help those who are trapped or hurt. Lacking gloves, 

crowbars, and training, some people claw through 

debris with bare hands. Ultimately, 95 percent of 

those who are rescued will be rescued by other 

victims, as has been seen in earthquake disasters 

worldwide.

Air traffic is being diverted from southern California.

As people start to assess their situations, millions of them discover they are 

cut off from their families, with no way to learn the fate of their loved ones or 

homes. This realization also hits first responders as they move out to help; they 

understand that the disaster may seem to be over but is just beginning. 

Fires are starting in countless ways. Power lines arc... gas appliance lines snap... 

chemicals spill and mix... a lamp hits a sofa, unnoticed with the power out and the 

earth shaking, then the power returns and the sofa starts to smolder... Most 

of the fires start small, but not all are discovered right away. In any case, the 

phones don’t have dial tones. Even if they did, in a disaster this big and widespread, there are not enough emergency personnel to immediately respond to 

every call for help. Worse, response is slowed by roads that are impassable due 

to damage, building debris, or abandoned cars. Worse still, in many places the 

water system is damaged, leaving inadequate water 

pressure for fire fighting.

Once started, a small fire needs only minutes to 

engulf a home or workplace. Around southern California on this day, there will be 1,600 fires large enough 

to warrant a 911 call. The stronger the shaking, the 

greater the number of fires ignited. In areas with 

densely packed, woodframe buildings, some of these 

ignitions will combine, spreading into conflagrations 

that burn dozens of blocks.

As soon as the shaking stops, experts race to 

inspect dams around the region. A few are found 

to be leaking at the toe—a sign of potential failure. Emergency responders are spread even 
thinner when they must begin the evacuation of downstream areas. No dam 

failures will occur in this particular earthquake.

Thursday 10:33 a.m. (... 33 minutes after the quake began...)

A magnitude 7.0 aftershock begins near the Salton Sea and ruptures to the south. 

Luckily, this is a relatively unpopulated area. Shaking and its effects are felt throughout Imperial and 

San Diego Counties, as well as in Mexicali, Mexico. 

Damage to a dam in San Diego County requires an 

evacuation. Teams of firefighters from San Diego 

County had been getting ready to come north to help 

with the initial earthquake’s aftermath, but are now 

diverted to respond to the strong aftershock affecting their own county. 

Thursday 12:00 noon (...2 hours after the quake 

began...)

Smaller fires are merging into larger fires in parts of 

the region where shaking was high and wood buildings 

are in close proximity. World and national news coverage is focused on urban Los Angeles, especially on a 

few collapsed buildings. This media focus makes the 

damage seem even worse than it is, and also more localized. It will be several days 

before a clear picture emerges of damage around the region.

Fire departments in Arizona and the San Francisco Bay area start to mobilize, but 

mutual aid is hindered because so many roads into the affected region are impassable. By now, some hospitals are beginning to receive and treat the injured, but 

with routes and communications disrupted, ambulances struggle to reach victims 

and get them to hospitals. 

November 14, 2008

Friday 03:17 a.m. (... 17+ hours after the quake began...)

A magnitude 7.2 aftershock begins near San Bernardino and ruptures west 

along the base of the San Gabriel Mountains. This 

earthquake is considerably larger than 1994’s 

magnitude 6.7 Northridge earthquake, which killed 33 

people and cost more than $40 billion. The rupture 

stops 18 miles east of Pasadena, near Monrovia. The 

location and size of this earthquake are devastating 

to the already-weakened infrastructure and 

overextended emergency response resources. The 

aftershock triggers damaging aftershocks of its own.

Friday 07:00 a.m. (... 21 hours after the quake 

began...)

By now, a Presidential Disaster Declaration has been 

issued, and Federal resources have been committed. 

The Federal Emergency Management Agency (FEMA), 

the California Governor’s Office of Emergency Services 

10 The ShakeOut Earthquake Scenario—A Story That Southern Californians Are Writing
(OES), and Operational Areas for emergency management have set up a Joint Incident 

Command Center. Communications remain difficult. Ham radio operators begin to assist 

official responders.

Since first hearing about the earthquake, people outside southern California have 

been trying to reach family and friends here. Very 

few have succeeded.

Friday 09:02 a.m. (...23+ hours after the quake 

began...)

A magnitude 5.6 aftershock rattles residential areas in 

Rancho Cucamonga. This is a bit bigger than the 1990 

Upland earthquake that caused more than $10 million in 

damage.

Friday 10:00 a.m. (...24 hours after the quake 

began...)

Utility companies are working around the clock to 

restore services, yet most people in the areas of 

heaviest shaking lack electricity, natural gas, and 

water. Utility workers, like transportation crews, medical staff, and emergency 

responders, push themselves to do their crucial jobs despite concerns about their 

own families.

Donations of money, services, and material are arriving from all parts of the United States, and a few 

Red Cross shelters have opened at public schools and 

undamaged recreation centers, where food, water, 

and personnel are available. Most people, particularly 

in heavily damaged areas, are camped outside.

By now, most stranded motorists have been rescued, and 

some families are at last reuniting. To get around, emergency responders are using helicopters and any other 

means of transportation that works, while residents are 

using bicycles and four-wheel-drive vehicles. 

November 15, 2008

Saturday 11:32 p.m. (... 2+ days after the quake began...)

A magnitude 5.7 aftershock occurs with an epicenter in Rialto. This is as large as the 

1991 Sierra Madre earthquake that killed one person and caused $40 million in damage.

Fear of looting far exceeds the reality, yet by now many fearful rumors are circulating. Despite official assurances to the contrary, concern grows that if dead 

bodies are not recovered and transported away, they will cause disease outbreaks. 

Some are convinced that earthquake scientists are hiding knowledge that an even 

bigger earthquake is imminent.

The ShakeOut Scenario Narrative 11
November 16, 2008 (... 3 days after the quake began...)

It is getting easier for people outside southern California to make contact 

with friends and family here. Urban search and rescue teams continue to make 

rescues, but at a declining rate. Firefighters have 

extinguished most of the major fires, except 

where some conflagrations have merged into 

super-conflagrations—monster fires that consume 

everything for hundreds of blocks.

Many medical staff members have worked without sleep since they first began responding to the 

disaster. Seriously damaged hospitals have been 

evacuated, and open-air trauma centers have been 

set up in adjacent areas. There is a very short supply of medical equipment such as kidney dialysis 

machines. Some patients are being med-evacuated 

outside the region, to hospitals in Nevada, Arizona, 

and other parts of California. Undamaged hospitals 

have an influx of earthquake victims with crush 

injuries, broken bones, and trauma. This increased 

patient load is not distributed evenly, and some 

undamaged hospitals are dramatically overloaded, while others receive few 

patients.

By now, Red Cross shelters have been set up throughout the accessible parts of 

the affected areas. The donation and distribution of money, services, and material 

have intensified, yet unmet needs are widespread. A 

coordinated effort among local, State, and Federal 

government agencies is starting to bring water and 

food into the region. Our “just in time” economy does 

not stockpile goods in warehouses.

The National Guard has been mobilized to handle specialized, earthquake-related law enforcement duties, 

allowing local law enforcement to return to regular 

duties. The fear of looting, intensified by media 

emphasis, begins to abate. Police and security personnel maintain cordons around sites of building collapse, 

but tenants and owners are allowed to reenter certain 

other damaged buildings on a very limited basis.

Mid-December, 2008 

(...About a month later...)

By now, most gas and electric services have been restored, even in the heavily damaged 

areas closest to the San Andreas Fault. Landfills store millions of tons of fresh debris. 

Most of the major roads have reopened, but they are lined with heaps of debris. Small 

bridges that went down or remain damaged are keeping many local roads closed. Some 

freeways also remain closed for repairs, where bridge retrofitting prevented collapse 

but not all damage. Many commuters who work far from home are unable (and some are 

12 The ShakeOut Earthquake Scenario—A Story That Southern Californians Are Writing
unwilling) to be back at work regularly. Tens of thousands of people are still without 

permanent shelter or jobs—or both—because their 

buildings sustained so much damage.

In the areas where shaking was not severe, most of the 

water service has been restored, although even in those 

areas a few communities continue to repair their water 

systems. Most people with running tap water have been 

warned to boil their water, because of confirmed or 

possible contamination due to cracks in the water conveyance system, particularly in areas where the sewer 

system also incurred damage. It will take a year or more 

for all the water systems to be certified as safe. 

In scattered areas throughout southern California, 

people still cannot flush toilets because of damage to 

sewer pipes. Plenty of water is stored in the ground 

and in reservoirs, but near the fault it is not reaching some homes, schools, and businesses that need it. 

By now, many of these communities have determined 

that it will be cheaper and faster to replace rather than hunt for and repair every 

break in their water systems. So many communities have placed orders for pipes 

and connectors that the orders are heavily backlogged and there is debate about 

whose orders should receive priority. 

A magnitude 6 aftershock with an epicenter in Cajon Pass offsets restored rail 

lines and disrupts the movement of goods from the ports once again.

In places without serious structural damage and with water service, businesses 

have reopened and are trying to get back to normal. Most had not secured their 

computers, their stock, or their files, or had these resources destroyed when 

unsecured water pipes broke. The few businesses with earthquake insurance now 

have the capital to move forward. Other businesses 

that survived the earthquake with little damage are 

nonetheless struggling because suppliers have not 

reopened or customers and employees are unable to 

reach them easily. Manufacturing plants that have 

resumed production are facing delays and additional 

costs to transport goods out of the region; some of 

their customers are considering other options.

Some residents have left the region to stay with 

family or friends, due to damage to schools and 

homes, or loss of jobs. At this point, most still expect 

to return.

Almost all the public K-12 schools and community 

colleges have reopened. Only a few of their buildings 

suffered structural damage, because they have special 

construction and inspection standards, regulated by 

the Field Act. In these schools, most of the nonstructural damage has been cleared, 

although undamaged furniture, equipment, and supplies are at a premium in many 

places. Class sizes are smaller where families have relocated to less damaged areas 

or are keeping kids at home. Not all teachers are back on the job.

The ShakeOut Scenario Narrative 13
Universities and private schools are not protected by the Field Act. Many have 

buildings that have not been retrofitted and thus have incurred significant damage. 

Some university students have now transferred outside the region. 

May, 2009 (...6 months later...)

Water is back in faucets, sinks, and air conditioning 

units across the region, but it is too late for many 

businesses, especially smaller businesses that lacked 

the resources to wait out the bad times. 

Businesses forced to close have a domino effect, and 

as the chances diminish for regaining jobs or finding new ones, more and more people are struggling to 

rebuild their lives.

By now, some faith communities have been forced to 

disband, due to severely damaged buildings and dwindling congregations.

Competition for building materials and construction crews is fierce. In communities that had been proactive in disaster planning, 

rebuilding is well underway. Other communities are still grappling with the complicated procedures and paperwork needed to launch 

post-disaster reconstruction.

Scattered around the region, there are multifamily 

residences that remain uninhabitable, with tenants 

still living outdoors.

Financial institutions face a growing number of loans 

in default, as businesses fail and individuals give up on 

recouping their losses.

November, 2010 (... 2 years later...)

Has this earthquake caused a disaster or a catastrophe? 

Are things looking up? Is life getting back to normal 

for most people? Have most residents returned to 

their homes? Have most lifestyles and businesses 

resumed?

or

Are things still going badly? Has recovery faltered? Have the systems that 

support life in southern California been too severely damaged? How many 

people have found their lives unbearably difficult since the earthquake struck? 

How many people have lost what matters most to them?

Southern Californians have the opportunity to work together to write this ending. 

In fact, by intention or not, they are writing this ending every day, through the 

decisions they make—or don’t make—to get ready for earthquakes.

14 The ShakeOut Earthquake Scenario—A Story That Southern Californians Are Writing
How Do We Write the Ending? 15

How Do We Write the Ending?

A major earthquake in southern California is inevitable, 

and it will be a regional disaster. Thousands of square miles 

will suffer heavy shaking, tens of thousands of people will be 

injured, hundreds of thousands of buildings will be damaged, 

and millions of lives and businesses will be disrupted. Whether 

or not the disaster becomes a catastrophe—an event that permanently changes the nature of life in southern California—

will depend on the choices that every person makes between 

now and the day the earthquake occurs. 

By examining the consequences of one hypothetical 

earthquake and the dynamic interactions among elements 

of our physical infrastructure and economic and social 

systems, the ShakeOut Scenario is helping to identify 

Although an earthquake has only one 

magnitude and epicenter, different 

locations will experience different 

shaking levels. The strongest 

shaking occurs very near the fault 

and dies off as seismic waves 

travel away. Away from the fault, 

natural basins filled with sediments 

trap some waves and create 

pockets of stronger shaking with 

longer durations. Not every basin 

traps waves in every earthquake. 

Consequently, in the ShakeOut 

earthquake, the San Fernando 

Valley experiences relatively low 

levels of shaking compared to 

the Coachella, San Bernardino, 

Antelope, and San Gabriel Valleys 

and the East Los Angeles area. 

The fault rupture modeled for the 

ShakeOut Scenario extends along 

200 miles of the southern San 

Andreas Fault, so it would take this 

section of fault about 100 seconds to 

rupture. Ground shaking continues 

as the waves move out, and from 

the first fault motion near the Salton 

Sea to the last strong shaking in 

Ventura, the hypothetical magnitude 

7.8 ShakeOut Scenario earthquake 

would shake southern California for 

more than 3 minutes. At most sites, 

strong shaking would last about 15 

seconds, but in the basins strong 

shaking would continue for as much 

as a minute as the earthquake 

waves reverberate.

potential points of failure and places where relatively small 

efforts or investments before the next earthquake could 

yield tremendous benefit after the earthquake. Perhaps the 

biggest lesson of the ShakeOut Scenario is that our individual and collective decisions intertwine. The future vitality of southern California depends on the sum of personal 

decisions regarding earthquake preparedness and resiliency. 

The sum includes everyone—tenants and building owners, 

students and retirees, corporations and corner businesses, 

individuals and groups, neighborhoods, and governments. 

Some efforts can be made immediately, such as storing 

water and protecting families; some efforts will take time, 

such as increasing volunteer preparedness and collaborative 

planning; and some efforts will require money, such as retrofitting problem buildings or strengthening infrastructure. 

DISTRIBUTION OF SHAKING INTENSITIES IN THE SHAKEOUT SCENARIO EARTHQUAKE
16 The ShakeOut Earthquake Scenario—A Story That Southern Californians Are Writing

These and many more steps can be taken, starting now, to 

protect all southern Californians from the earthquake disasters that are certain to come. 

The USGS developed the ShakeOut Scenario at the 

request of community leaders and emergency responders 

Under normal conditions (blue line), the economic activity in a 

region will gradually grow with time. When a disaster strikes 

(red line), assets are lost and many businesses shut down. 

As power and water service are restored, some businesses 

reopen, and an influx of insurance payouts and government 

assistance is used to hire contractors. This can lead to a rapid 

regeneration of economic activity and a return to economic 

health within a couple of years (orange line). To an economist, a 

disaster becomes a catastrophe (purple line) when the regional 

economy suffers a breakdown in resilency and sinks into a 

depression that could last decades. To a sociologist, a disaster 

becomes a catastrophe when social, economic, and political 

systems suffer severe disruptions.

DISASTER OR CATASTROPHE?

who said that this was the kind of science they needed to 

improve southern California’s earthquake resiliency. Through 

this and upcoming projects, the USGS and its partners are 

continuing to evolve the way that hazard science is done, to 

help protect all of us from natural disasters.

All Californians live in earthquake country and 

should therefore be prepared. Information in English 

and Spanish on earthquakes in southern California 

and how to prepare for them can be found in Putting 

Down Roots in Earthquake Country (Echando Raíces 

en Tierra de Terremotos), available at http://www.

earthquakecountry.info/roots/.

Prepare 

Now to Ensure a Better 

Outcome!!!

Additional Information

The ShakeOut Scenario (U.S. Geological Survey Open-File 

Report 2008-1150; http://pubs.usgs.gov/of/2008/1150/)

Forecasting California’s Earthquakes—What Can We Expect 

in the Next 30 Years? (U.S. Geological Survey Fact Sheet 

2008-3027; http://pubs.usgs.gov/fs/2008/3027/)

http://urbanearth.usgs.gov/

http://www.daretoprepare.org/

Photographs in The ShakeOut Scenario Narrative (in order of appearance)—

Trucks on freeway: courtesy Port of Long Beach; Los Angeles cityscape: copyright 

by and courtesy of Erik Arnesen; Back to school after Hurricane Katrina: courtesy 

FEMA; Loma Prieta quake damage Salinas: USGS by J.C. Tinsley; Crushed bikes 

Loma Prieta quake: USGS by C.E. Meyer; Kitchen damage Northridge quake: 

USGS; Broken gas meter, Watsonville, Loma Prieta quake: USGS by H.G. Wilshire; 

Damaged apartment, Northridge quake: courtesy FEMA; 2007 Peru quake victims: 

copyright and by Michael Mullady; LA Structure fire: courtesy Los Angeles County 

Fire Department by Capt. Larry Collins; LA firefighter being interviewed: copyright 

and by Troy Case, courtesy of Los Angeles County Fire Department; Nighttime fire: 

courtesy Los Angeles County Fire Department by Capt. Larry Collins; Helicopter, 

Northridge quake: courtesy FEMA; Northridge quake victims with tent: courtesy 

FEMA; Firefighter with chainsaw: courtesy Los Angeles County Fire Department by 

Capt. Larry Collins; Red Cross trucks: courtesy FEMA; Loma Prieta quake damage: 

USGS by C.E. Meyer; Red-tag sign Loma Prieta quake: USGS by John Nakata; Bankowned sign: USGS by Dale Cox.
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Perry and others—The ShakeOut Earthquake Scenario—A Story That Southern Californians Are Writing—Circular 1324 / CGS Special Report 207

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