Emergency Water
Depending on how many episodes of Doomsday Preppers you have watched, your view on this may be slightly skewed. And every website from FEMA to the state has a different recommendation on how long you should expect to be sufficient on your own. Most people have heard 3 days, 7 days, 10 days (as made famous from Hurricane Sandy), or 2 weeks. Am I missing any others? But lets be realistic, who has the time or the space to store that much of anything (space is a valuable commodity in CA). Events such as Sandy highlighted that 10 days should be the standard, but FEMA hasn't jumped on that bandwagon yet. Until there is some consensus out there, I would aim for a minimum of 5 days-7 days. (NOTE: You should use this only as guidelines and make adjustments for your family and your own particular needs. This in no way is an endorsement or formal recommendation.)
Below are some tips to help you stockpile emergency water:
Remember this algorithm; 1gallon x per person x per day... This includes drinking, cooking, and bathing, so if you decide to forgo bathing, take that into consideration (however you may have a public health emergency on your hands if you neglect this for any sustained period of time and no one will appreciate that).
To determine adequate quantities, take the following into account:
Individual needs vary, depending on age, physical condition, activity, diet, and climate.
Children, nursing mothers, and ill people need more water.
Very hot temperatures can double the amount of water needed.
A medical emergency might require additional water.
Consider your animals when determining quantities of water
Set-aside water specific too cleaning wounds (this should not come out of your 1x1x1 calculation)
Buy Vs Prepare
If you choose to prepare your own, follow the EPA guidelines for proper cleaning and storage of homemade water containers. But, why make your life even harder, go buy it. Commercially bought water from your local market should suffice. Keep bottled water in its original container and do not open it until you need to use it. Observe the expiration or “use by” date. You can also purchase water from sporting good stores or disaster survival companies I like the company "More Prepared". They are local to the South Bay and have great customer service. And they DELIVER! (http://www.moreprepared.com/?affiliate_id=1289).
Storage
Where you keep it may change the shelf life. Consider things like extreme heat, cold, or other factors that may degrade the water. A good rule of thumb is to rotate through it every 6 months, you may be able to go longer depending on where you store it. If you purchase plastic bottles, ensure they are not stored directly on concrete as concrete absorbs water. Place them at least 6 inches off the floor, preferable on a cooler or pallet.
Water Sources
If you are a procrastinator and wait until its too late to purchase your disaster water, there are a few place within your home you can find, and purify water. (NOTE: Never drink pool or spa water. Any water that is being treated with chemicals should be avoided at ALL costs. This is not a viable alternative). However, here are a few...
Water Heater (you will need a garden hose)- be cautious as heavy metals can accumulate in your water heater and can be VERY dangerous if consumed.
Back-side of the toilet bowl (do not use if you treat your water, or if its blue or some other color)
While valid sources, you will need to purify the water from these sources prior to drinking...
Water Purification Follow the EPA guidance on water purification.
http://water.epa.gov/drink/emerprep/emergencydisinfection.cfm