Ensuring you have a clean drinking water reserve and learning to purify contaminated water has to be right at the top of your emergency preparation list. You really should try to set aside at least a two week water supply. Depending on age, medical needs, diet, and climate, each person's water need will vary. But, a rule of thumb is that a normally active person needs at least 1/2 gallon of drinking water every day to stay hydrated. Hot weather, high activity, and other factors may increase that need. You've also got to consider water needed for cooking and personal hygiene. One and a half gallons per day per person is a good guideline.
Use this calculator to determine how much water you need to store:
Short-Term Evacuation Needs
If your emergency plan is to evacuate your home, then you only need to have water that you can carry with you. Water weighs 8 pounds per gallon so you won't be taking much along. A 3 gallon collapsible plastic jug will be enough for your family for a one-day evacuation. As long as your plan works and you can get out of town, you'll be ok.
But, if you plan to stay put or are stuck in your home, you will need more water.
You could run down to Costco or Sam's Club and buy a few cases of bottled water if you want. It is clean and can be stored a long time. But, it is also awfully expensive. If you normally drink your tap water and it comes from a municipal water supply, you can bottle it for storage. If you have a well or unregulated water source, you may need to boil it first.
You can store your water in thoroughly washed plastic, glass, fiberglass water storage tanks, or enamel-lined metal containers. Never use a container that has held toxic liquids because small amounts may leeched into the container material. Strong plastic containers, such as 2 liter soda bottles, are good choices. You can also purchase food-grade plastic buckets or drums. Don't use plastic milk jugs unless you have no alternatives because it is very difficult to clean them thoroughly.
Treat your water with chlorine bleach to prevent the growth of microorganisms that will ruin the water. Use plain liquid bleach that contains 5.25% sodium hypochlorite and no soap or scent. Add four drops of bleach per quart of water (or 8 drops in a 2 liter bottle), and stir well. Seal your water containers tightly, label them with the date, and store them in a cool, dark place.
Emergency water storage needs a dark, cool location. A corner of your basement is perfect, otherwise setting aside a closet as your emergency pantry works. Be sure that shelves are capable of carrying the heavy load of water.
Using Emergency Water
Remember these tips when it comes time to use your supply. Posting these right at your storage location would be a good idea.
Finding Water at Home
If your water supply runs low or a disaster occurs before you are ready (shame, shame) you still have a few gallons of potable water stashed in your home that you may not know about. To prevent contamination of the water already in your home, immediately shut off your main water valve in case the municipal supply has been compromised. Get containers ready to hold your water before you start collecting the following:
Emergency Water Sources
Before you run out of water, start looking for a replacement source. Assume that all water outside your home is contaminated and will need to be purified in some way. Visit the Water Dude web site for lots of stuff about water filtering, purification, and treatment.
You can collect rainwater from your roof, snow from your yard, water or ice from lakes, streams, and springs. All of these sources will have contaminants ranging from dirt and bugs to chemicals and microorganisms. You have to treat it before drinking it.
You definitely should have a hand-pump water filter in your emergency kit. A good one will remove the vast majority of dirt and microorganisms from local water. Then, boil the filtered water for 10 minutes, let it cool, and its good enough. If you have no heat, use 2 drops of chlorine bleach in each quart instead of boiling and let it sit for at least 30 minutes.
If there is a danger of radioactive fallout in the water, you can either filter it or distill it. The water does not become radioactive - it has radioactive dust floating around in it. A backpacking wate filter will remove it.
If your emergency water supplies begin to run low, do not ration water. Drink the amount you need today and find more for tomorrow.