“What could we do if suddenly we were confronted with the prospect of no power, not for a few hours, but perhaps days, weeks, or longer?”
The large critical systems that sustain life, known as critical infrastructure (power, water, telecommunications, food and agriculture, transportation, etc.) are reaching the end of their respective life cycles, which makes them very vulnerable to all hazards (natural, technological, and human caused). Electricity makes modern life possible, from pumping and treating of water to driving our economy and, for almost every modern convenience.
Without the grid, the U.S. would technologically be pushed back to the 1890s. As an example, on average a typical cell phone will only last 24 hours per charge with minimal communications. The average battery life of these devices for those who constantly talk on cell phones is about 4-5 hours. Let’s look at a scenario. The ‘big one’ refers to an earthquake initiated just southeast of Los Angeles (18 million people in the metro area), near the north tip of the Salton Sea that a great many geologists indicate will occur, they just do not know when. Almost certainly, transportation, power, and water distribution centers in the LA area would be significantly affected or lost. Thus, you need to be prepared for the mundane to the extreme.
Clogged or no communications via phone and/or no vehicle transportation, no water supplies, no emergency services, etc. A good 2-5 day backpack stocked with emergency food, water and other supplies for 3 days, a good pair of hiking boots, and an exit strategy for where to go and how to get there should be on your list. Assume the absolute worse-case scenarios from being stuck where you are to the need to hike miles on foot to a safe location – depending on where you live. With overtaxed health care and other government systems you cannot expect government to come to your aid; logistics will simply make that untenable – use Hurricane Katrina as your example and, common sense.