You should store at least one gallon of water per person per day. FEMA recommends having a 3-day supply of water per person. Irecommend storing at least 2-3 weeks of water per person. Much conflicting information exists regarding water storage. While this article is subject to change here are key points that I found.
- Water Rotation: Should you rotate your water every year to keep it fresh? I read conflicting information on water rotation but I prefer to err on the side of caution. Well sealed containers should protect water against contamination for many years. However, rotating your water is fast and easy. Just wait until you have warm weather, empty your containers in your garden (recycle the water), and refill.
- Water Treatment: Some sites recommend treating water with chlorine or other chemicals to prevent growth of algae and microorganisms. I read that nearly all city water is treated with enough chlorine to kill microorganisms and keep the water stable. I would still filter stored water before using it. Filtering removes microorganisms and chemicals to make the water safer and better tasting. If you insist on treating the water then use tablets or 1/8 teaspoon of chlorine per gallon of water.
- Water Use: If you have good, sealed containers then the water should be ready to drink directly from the container. The water may have a funny taste due to chemicals or lack of oxygen. However, I recommend treating the water before drinking it (err on the side of caution). I would boil or filter the water to remove microorganisms, chemicals, and to make the water taste better. A 0.02 micron filter should remove biological contaminants including bacteria and viruses.
I recommend storing water slightly above the ground to prevent ground contact issues. Stacking water containers on a recycled wooden pallet is a nice option. Do NOT store water containers anywhere where leakage could cause a problem. Assume that a container will leak (it probably won’t but be prepared) and situate the container accordingly. The safest water storage containers are polyethylene-based plastics, or plastics #1, #2, and #4. Water barrels made out of plastic #2 are BPS-free and good for long-term storage.