Water Heater – If your house uses gas for heat, you undoubtedly have a water heater. Inside you will find a moderate reserve of water.
Canned Goods – Tuna, canned vegetables, beans and fruit all contain liquids that can be drained, weigh the risks.
Pipes – If you live in a multilevel home, you can drain the water in your pipes by using gravity to your advantage.
Toilet Water – In an emergency, boil the water from the upper tank (not the bowl) of your toilet. I would only use this water as a last resort and only if I was sure it was free of chemicals.
Rainwater – Use large pots and containers to catch and store rainwater.