TL;DR one gallon of water per person per day, expect a boil-water order for one month and disruption of telco and transit for a bit, so keep a stash of cash on

TL;DR one gallon of water per person per day, expect a boil-water order for one month and disruption of telco and transit for a bit, so keep a stash of cash on hand. Stay put for the immediate time after the foreshock and aftershocks. Not much else you can do.