If we were rational people, the evacuation of California would begin today. The destruction of Haiti by a magnitude 7.0 earthquake is not only an immense catastrophe, of Biblical proportions, for that accursed country, but is also a prophecy for California. Earthquakes do not strike only the poor. Nor are they always a surprise.
Along geological fault lines, where tectonic plates — huge chunks of the earth’s crust, floating like enormous icebergs on the molten magma of the earths interior — grind past or into each other, the accumulation of strain and its release as earthquakes is a pretty regular process because the velocity of the plates does not change much. In California, the Pacific Ocean plate and the North American plate move past each other along the San Andreas Fault at 2.9 inches per year. Thus the best indicator yet discovered of when an earthquake will strike in the future is the frequency with which earthquakes have struck in that particular spot in the past. Along the Southern San Andreas, from Baja California northward to a point roughly midway between Los Angeles and San Francisco, the geologic record shows major earthquakes, of about magnitude 8, occurring with metronomic regularity every 150 years. The last one occurred in 1857. Do the math.
Two points about scale here: a magnitude 8 earthquake is not a little bit larger than a magnitude 7, it is ten times more powerful. And an estimate in geologic time is not going to be accurate to the hour. If I told you I’d do something in 15 minutes, and did so in 10 or in 20 minutes, you would not accuse me of inaccuracy. The fact that the LA earthquake is three years late is not significant.
In northern California, around San Francisco, the frequency of the big ones along the San Andreas is not known. The last time the city was destroyed by one was 1908, when the fault snapped along 270 miles of its length, displacing its two sides by as much as 16 feet. The tributary Hayward Fault has produced magnitude 7 quakes every 140 years, the last one having occurred in 1868. And the Hayward fault runs directly under San Francisco (the football stadium at the University of California/Berkeley straddles the fault, its two halves built separately so they can slide past each other if necessary). In 1908 the lateral movement of the plates snapped the water lines coming into the city, leaving the residents no way to fight the multiple fires, some fed by ruptured gas mains, that consumed it.
Exactly the same thing would happen today: the Hetch Hetchy aqueduct, carrying water for 2.4 million people, crosses the Hayward Fault. Official estimates of the consequences of a quake the size of the 1908 event include 5,800 people dead, 220,000 homeless, virtually all the bridges and freeways in the area destroyed and the Port of Oakland out of business for a very long time. The Port is the fourth busiest container port in the United States.
A magnitude 7 earthquake near Los Angeles will be much worse. The U.S. Geological Survey estimates that up to 18,000 people would die, every freeway and most railways and gas lines in the city would be destroyed, and damages would total something over $250 billion. That is ten times the death toll, and three times the damages, of Hurricane Katrina, the costliest and one of the deadliest hurricanes ever to strike America. And it would be far worse than Katrina in many more ways:
- There will be no notice, no evacuation, no boarding up of windows or shopping for supplies. Everything will be normal one minute and destroyed the next.
- More than half of the losses incurred in Katrina were insured; in the San Francisco Bay area only about 8% of homes and businesses are insured for earthquake damage.
- According to a USGS study, less than 10% of people living on and near the San Andreas have made a plan for surviving the next big earthquake, and less than half have set aside some provisions such as water, batteries, or first aid kits.
- When Katrina came ashore, it made a choice, and by choosing New Orleans spared, say, Galveston. But the earthquake that strikes Los Angeles will in no way reduce the peril to San Francisco.
Let us be clear: this is not something that might happen, these earthquakes are going to happen. The scientific consensus on this is far older, and more complete, than that on global climate change. Journalists who occasionally do a story on the impending earthquakes do not feel it necessary, in order to appear fair and balanced, to scour the warrens of academe to find someone who denies it all. And yes, geologists have long predicted that Haiti, which sits astride the boundary of the North American and Caribbean plates, was due for a magnitude 7.2 quake.
It is not only the water and gas lines going into L.A. or San Francisco that will snap in the Big One; the supply lines for everyone living west of the Mississippi River run in large part through the ports of Los Angeles, Oakland and Long Beach. For the reasons discussed in Chapters One and Five, a substantial interruption of oil and food supplies to a major chunk of the country may not be repairable. The combination of burdens – treating the casualties, housing and feeding the refugees, putting out the fires, repairing the infrastructure — while the larger economy freezes up ever farther to the east for lack of essential supplies, could bring down the entire shaky edifice of our industrial world.
Pray for Haiti. Help Haiti. And then reflect: who will help us, on the day we confront Haiti’s fate?