There is an old adage that states that "If you don't learn from the mistakes of the past, you are bound to repeat them". As the 108th anniversary of the Great San Francisco Earthquake comes and goes, we would be wise to pause and reflect on the loss of property, available housing, and death that occurred on April 16th, 1906. The earth shook and reminded the citizens of a city known as Baghdad By the Bay that we are all small and vulnerable compared to the mighty power of our mother earth.
The threat of another large earthquake in many heavily populated areas of our country has been forecast by almost all recognized experts in the fields of science related to seismology, geology, paleoseismology, and geophysics. The root cause has been determined to be the relentless march of the tectonic plates that have overtime changed the layout of the landmasses on which we live, play and work. An example is the change in positions between the North American Plate and the Pacific Plate where history has shown an average of nearly two inches of movement per year as Los Angeles marches slowly toward San Francisco. Measurements taken at the surface do not reflect that amount of movement in all places along the plate boundary indicating a build up of strain energy in the soils and rocks that support our homes.
When the next big one hits, there will be significant economic losses, primarily in lost housing and lost or diminished values to property. And although wood houses are inherently quite safe, in some cases there will be deaths from improperly designed or improperly retrofitted houses. When houses do collapse, they bring with them the possibility of fires. On a large scale, multiple fires would likely overwhelm even the best and most prepared fire fighting equipment and personnel.
When a major earthquake strikes the Bay Area, the region could face thousands of casualties, hundreds of thousands of displaced households and losses in the hundreds of billions of dollars. The lives of San Franciscans will be enormously disrupted, and it could take months to reestablish essential services. Recovery will be slow and will depend on the extent of the building damage, the amount of business lost, the availability of utilities and how quickly communities can repair and rebuild their housing.
SPUR Report 1/2012