This scenario earthquake is for a magnitude 6.7 earthquake on the West Napa fault in Napa County. An event along the West Napa fault would cause the most severe damage in Napa County. San Francisco, Alameda, and Solano counties would share the majority of the rest of the damage. As is the case with previous events, the older housing stock in Alameda and San Francisco counties would experience the most damage.
Napa County is clearly the hardest hit county in both gross numbers and percentages.
Over twice as many people from Napa County are expected to be displaced than from San Francisco, and over three times than from Alameda County. Similarly, Napa County's peak shelter population is larger than Alameda and San Francisco counties combined. These relationships alone are not enough to prove a correlation between uninhabitable mobile homes, multi-family dwelling units and the generation of shelter populations. However they do seem to suggest an association between certain housing types and the probability of going to a shelter in the event of a major earthquake.