I've been running a preparedness group in Central Florida for the past 18 months, so I study and prepare on a daily basis. Let me recommend a low cost and very critical purchase to everyone, calcium hypochlorite. A small bag of this can purify your family's water for YEARS.
Many municipalities use calcium hypochlorite to purify city water supplies. Commercially it is most often sold as 'pool shock', however you must select a product carefully to make sure it truly is calcium hypochlorite, and that it doesn't have harmful additives (e.g. algaecides, etc).
One of our group members located a good, low-cost source. The price was so good that I ordered ten bags just yesterday. Here's the source:
http://www.poolgeek.com/GLB-Super-Charge-P2273.aspx
Other things to know:
Calcium hypochlorite is one of the essentials for the serious prepper. If you obtain it be sure to look up instructions for using it to purify water on the Internet and have them printed somewhere for future reference.
My son (PhD physics) says that 'store bought' bleach will lose about 50% of it's strength per year.
Thanks for the suggestions. yep - print it out now because the internet may not be there when you need it. Sadly - Americans voed for destruction in 2008 and they drool over TV and TV keeps him in power.
I feel sorry for seniors and baby boomers the most. The young will have a chance to start over after TEOTWAWKI. Sadly - I feel America will be more like Mad Max/Zimbabwe than Argentina or the collapsed USSR. It will be worse.