Water in a Plastic Bottle

How to Purify Water with Sunlight

Water is the single most important thing a person needs in a survival situation. Without water a person can only survive 3-5 days. However, it’s extremely important that the water consumed is not contaminated.

Contaminated water can lead to several illnesses such as typhoid fever, dysentery, diarrhea, and many more.

In a survival situation, these otherwise minor illnesses can become deadly. This is why drinking clean water is so important.

Survival Water Purification

Purifying water removes biological contaminants, heavy elements, and chemicals from water. There are many ways to purify water, but in a survival scenario your options will likely be very limited.

Depending on your situation, you may be fortunate enough to be carrying some sort of water purification system with you. This is especially true if you are a thru hiker or someone on a multi night hiking trip.

If you are unfortunate enough not to have one of these systems with you, you’ll have to make due.

Water Bottles

If you have a plastic water bottle with you or any other clear container which you can store water, consider yourself fortunate. If you don’t, keep your eyes open looking for a bottle while you work on the other important things (locating water, finding or making shelter, and getting a fire going).

How to Purify Water with a Plastic Bottle

Fill the water bottle with the questionable water. You can run the water through cloth to help filter out any large particles.

Water in a Plastic Bottle

Put the bottle of water in the sunlight for a minimum of 6 hours standing up right. It’s important to leave the water bottle alone for as long as possible, but move it if you need to as the sun moves throughout the day.

The ultraviolet light will kill most of the bacteria and protozoa, helping to improve the quality of the water.

Leave the water bottle undisturbed and upright to allow any particulates and solids to settle to the bottom of the bottle.  Drink the water slowly to let the dirt and particles stay near the bottom so you don’t drink it.

How to Get the Most Out of Water

After being in the sunlight for hours, the water will be very hot. If you are in desperate need of water, drink it and don’t worry about the temperature. Be forewarned that this can raise your body temperature though.

But if you are in decent shape, wait until the water has reached about body temperature. The body needs to adjust any water consumed back to body temperature. So if the temperature either much higher or much lower, the body will consume precious calories to bring it to the right temperature.

Leave a Comment