The mega-earthquake.
It's coming.
We don't know exactly when
or how big it's going to be,
but it's coming.
It will be chaotic,
and with millions of lives on the brink,
California will be put to
the ultimate test.
1,800 people will die.
1,600 fires will ignite.
750 people will be trapped inside buildings.
270,000 people will be unable to return home.
50,000 people will need emergency care.
Search and rescue efforts
will last for 19 days.
These numbers are from
the United States Geological Survey.
They have estimated that if a 7.8 earthquake
hits along the southern San Andreas Fault
on a non-windy day at
about 9 a.m.,
we will be thrust into this
frightening scenario.
They are also warning there is a 20% chance
"the big one"
could hit the San Andreas Fault
sometime in the next 30 years.
Some experts predict it could be
a catastrophic 8.2 magnitude quake.
It's a boundary between the Pacific plate
and the North American plate.
The fault extends into California roughly
1,200 kilometers (746 miles)
from Cape Mendocino to the Mexican border.
Cities like San Diego, Los Angeles,
and Big Sur sit on the Pacific plate.
The North American plate has
San Francisco, Sacramento,
and the Sierra Nevada.
San Andreas is a transform fault.
This is when two plates slide
past one another.
The average speed of the moving plates is
0.6 centimeters (0.2 inches) a year.
Although this doesn't seem like much,
they will actually lodge themselves together
and not move for years,
and this is where the problem starts.
Imagine the damage as built-up strain
finally releases and breaks the rock
along the fault.
This causes the plates
to shift a few feet all at once.
The sudden release of energy
creates seismic waves,
and it's these waves we feel
as earthquakes.
The San Andreas Fault has experienced
massive earthquakes in the past.
The Great 1906 San Francisco Earthquake
is one of the most significant
earthquakes of all time.
At 5:12 a.m., on the morning of April 18th,
a foreshock was felt throughout
the Bay Area.
Then, 20 to 25 seconds later,
the earthquake hit.
The estimated magnitude was 7.9,
and the violent shocks lasted
for 45 to 60 seconds.
It was so powerful it was felt from
southern Oregon to the south
of Los Angeles and inland as far as
central Nevada.
It's been estimated that around
2,100 to 2,800 people died that day.
If the mega-earthquake hits
California tomorrow,
what sort of devastation could
we be dealing with?
If it is "the big one,"
it would have a magnitude of about
eight that would rupture a 322 km (200 mi)
stretch along the southernmost part
of the fault.
Buildings built before 1980
are in danger of collapsing.
A recent study suggests that up to 25%
of the buildings constructed to the current
earthquake code will be unusable
after the quake.
After "the big one,"
explosions could be triggered,
and fires would erupt throughout
the devastated cities.
Landslides could lead to
more fatalities and damage.
Electricity and sewage could come
to a halt along with transportation.
Highways, railways, airport runways,
and bridges could become unstable
for weeks and even months.
One of our basic survival needs
is access to fresh water,
which will be difficult after the quake.
The major aqueduct infrastructure that
pumps water into Southern California
crosses the San Andreas Fault.
So, it seems unlikely that this
would be unaffected.
Now if you are thinking it couldn't get
any worse than that,
parts of the San Andreas Fault
also intersect with
oil and gas pipelines.
If these pipelines break,
the lethal consequences both for
human health and the environment
will be devastating.
California has the fifth largest economy
in the world.
So, not only would the effects be felt by
California and the U.S.,
they would also impact the world.
The estimated cost of "the big one"
is $200 billion.
$33 billion of this comes from property
damage and $50 billion in lost
economic activity.
Less than 20% of California buildings
are covered by earthquake insurance,
so most people will need to pay
the rebuilding cost.
These same people might decide to
relocate to other parts of the United States.
This trend in the dropping population was
observed in Los Angeles after the
two earthquakes of 1971 and 1994.
The population decreased for two years
after both quakes,
and these were relatively small,
having magnitudes of 6.5 and 6.7.
Then there is the business impact.
Not just to California from the mass
exodus of population,
but also California's importance to the
rest of the United States.
Over 40% of total imports to the U.S.
come in through Los Angeles
and Long Beach ports.
And with the massive disruption
of transportation routes,
especially those that cross
the San Andreas Fault,
getting these goods to the rest
of the country will be
difficult to say the least.
So, with the largest U.S. economy
and the fifth largest in the world crushed,
would this send us into another
global economic crash?
What could the future of the U.S.
and global economy look like
after this?
Well, that's a story
for another What IF.