Some of the most beautiful untamed places to camp are also the most remote and without a way to pasteurize your water trouble is sure to follow. When camping in the back country you just can't bring enough potable water so this means you will be drinking water right out of a stream or lake. While the water might be palatable, it is those hidden pathogens that can make us sick. Contrary to popular belief though, water need not be boiled to render it safe for human consumption.
Pasteurizing your water instead of boiling it can save a lot of fuel, or eliminate the need for fuel entirely when used in conjunction with a solar oven. The challenge is knowing when your water has been safely pasteurized, and a WAPI is the easiest way to do that.
What is a WAPI?
A "Water Pasteurization Indicator," or wapi, is a small reusable device that takes the guesswork out of determining when the safe water pasteurization temperature has been reached. It is far more practical and durable than a thermometer and can be taken anywhere.
The Wax that Melts at 150F - The Super Wapi
Originally designed to work in conjunction with solar ovens, Water Pasteurization Indicators are a great way to save fuel while still assuring the safety of your drinking water. Most dangerous pathogens frequently found in drinking water can be killed by pasteurizing water, which means it needs to be heated to 65C or 149F for 5 minutes. Pasteurizing water is much less energy intensive than having to boil it to 212F. This energy savings makes safe drinking water more affordable and convenient, especially for those in undeveloped regions, campers, and others in circumstances where fuel may be limited.
Symptoms of contaminated drinking water:
Waterborne diseases can be caused by protozoa, parasites, bacteria, and viruses and they can lead to many agonizing symptoms ranging from diarrhea, bloody stools, and dehydration to nausea, vomiting and stomach cramps. According to the World Health Organization, 1.8 million people die from waterborne diseases every year. Many of these casualties are children.
How does the Wapi work?
A Super Wapi contains a special type of wax with a melting point of 150 degrees, inside a strong, but thin, transparent polycarbonate tube.
- Put the Super Wapi in the container of water to be heated, such as inside a solar oven, stove, or campfire. The stainless steel chain hangs over the edge for easy removal.
- Wait for the wax to melt, indicating the temperature of the water has reached 150F, set your timer for 5 minutes and hold it at that temperature.
- Allow water to cool, and be sure to drink only from a clean container. According to studies conducted by microbiologist Dr. Metcalf, 99% of the dangerous pathogens found in drinking water will be inactivated within five minutes once the pasteurization temperature has been reached.
When NOT to use a Wapi:
Water pasteurization is not suitable for water that is chemically contaminated, or brackish.