How to Sterilize Water?

The most common and effective method to sterilize water is by boiling it.

Here's a detailed explanation of how to sterilize water effectively:

Boiling

Boiling is a reliable way to kill most harmful bacteria, viruses, and protozoa present in water.

Bring the Water to a Rolling Boil: Heat the water until it reaches a rolling boil, which means there are continuous, vigorous bubbles rising and breaking on the surface.
Boil for One Minute: Once a rolling boil is achieved, maintain the boil for one full minute. At altitudes above 6,562 feet (2,000 meters), boil for three minutes due to the lower boiling point of water at higher altitudes.
Cool and Store: Allow the water to cool down completely before drinking. Store the sterilized water in a clean, sanitized container with a tight-fitting lid to prevent recontamination. The container should not have been washed in potentially contaminated water.

Clarity: Boiling sterilizes but doesn't remove sediment or chemicals. If the water is cloudy or contains particles, filter it through a clean cloth, coffee filter, or allow sediment to settle before boiling.
Taste: Boiling can make water taste flat due to the loss of dissolved gases. You can improve the taste by shaking the water in a clean container or pouring it back and forth between two containers to reintroduce air.
Containers: Ensure containers used for storage are thoroughly cleaned with soap and hot water or sanitized with a diluted bleach solution (1 teaspoon of unscented household bleach per gallon of water).

While boiling is the most common, other methods exist, though they may not be as effective in all situations:

UV Light: UV water sterilizers can kill bacteria and viruses but require the water to be clear and free of sediment for the UV light to penetrate effectively. These are often used in water purification systems.
Water Purification Tablets/Drops: These typically contain chlorine or iodine and can kill many microorganisms. Follow the product instructions carefully regarding dosage and contact time. These often leave a taste.
Solar Disinfection (SODIS): Expose clear water in a transparent plastic bottle to direct sunlight for at least six hours. This is effective against many pathogens but requires clear weather and may not kill all types of microorganisms.

In summary, boiling remains the most universally accessible and effective method for sterilizing water, ensuring it's safe to drink.