During emergencies you may not have access to safe water.
Treating water to make it safe to consume could be your only option. There's several ways to accomplish this.
Tablets or filters
Include water purification tablets or water filters in your emergency preparedness kit. They are available at most sporting goods stores and online.
Disinfect water by boiling
Filter debris. Collect water in a container and allow suspended particles to settle to the bottom of the container, or strain water through clean cloth or paper towels to filter out large debris in the water.
Boil water for 3-5 minutes. Some water will evaporate during this process. Cool water before drinking. Improve taste by pouring the water back and forth between two clean containers.
If it's not possible to boil water, use 5.25 percent sodium hypochlorite household bleach to disinfect water.
Scented and color safe bleaches should not be used.
On clear water use 8 drops (1/8 teaspoon) per gallon, or 16 drops (1/4 teaspoon) per gallon for cloudy water. Mix thoroughly and let stand for 30 minutes. If you cannot detect a slight chlorine odor after standing, repeat the process. Bleach potency diminishes with time, so store a bottle with your emergency water supply and replace on the same schedule as your stored water.