It doesn't seem too long ago that the Loma Prieta earthquake of 1989 shook up the city of San Francisco in detrimental ways, even causing the bay bridge at the time to collapse. Although the epicenter of the earthquake was located near Santa Cruz, the shockwaves that hit San Francisco did the most damage due to the composition of the soil that the city and bay is built on. Much of the sediment that the Bay Area is built on is man made and water logged, allowing instability and vulnerability to earthquake shockwaves.
But WAIT, there's MORE!
Not only is the Bay Area especially susceptible to damage due to tectonic plate movement, but the most imminent danger is that of sea level rise and subsidence.
Because the sediment is so unstable, a majority of the Bay Area is subject to a geologic process of mass wasting known as subsidence. This type of mass wasting is the rate of land sink an area is subject to. For San Francisco, it is an ongoing and prominent issue seeing as the coastline is heavily populated. Every year, the Bay Area sinks about 2 millimeters. By 2100, scientists and geologists estimate that due to subsidence, about 30 to 50 square miles of the Bay Area would be lost to this land wasting. In addition to subsidence, the natural rise of sea level will also contribute to land loss, totaling a loss of about 165 square feet.
For those that live in the Bay area, it's enough to compete with an ever growing population and astronomical housing market, but land sink and sea level rise could be the icing on the cake for some to justify moving somewhere more economically and geologically stable. The San Francisco Bay Conservation and Development Commission offers a comprehensive list of "Areas Vulnerable to Sea Level Rise in San Francisco Bay" on their website for those of you who are curious as to if your home will be effected or not!
New shorelines, that's pretty crazy!