How to Survive the End of the World as We Know It - James Wesley Rawles [27]
Water-Pasteurization Indicators and Heating Water
Water-pasteurization indicators (WAPIs) are now commonly used in the Third World to save fuel and time when treating drinking water. Water that is heated to 149 degrees for a short time is free from living microbes. Water does not have to be “boiled for ten minutes,” as some have erroneously suggested in the past. A WAPI is a simple, small, and low-cost tube with a special soy wax that indicates when water has reached a safe pasteurization temperature.
Alternatively, you can heat your water, using a dairy thermometer to be sure the water reaches 149 degrees. You can also use a kitchen or roasting thermometer, but since they are notoriously inaccurate, add ten degrees, just to be on the safe side.
Pool Shock: The Low-Cost Lifesaver
Pool-shock chlorination tablets can be bought in a five-gallon pail—enough to treat many thousands of gallons of water. Calcium hypochlorite (sold as pool shock) may be used to make your own bleach solution. Here is the information in a nutshell:
Use one heaping teaspoon of granular calcium hypochlorite (approximately .25 ounce) for each 2 gallons of water; dissolve in a plastic or glass container. (Don’t use a metal container, or it may react with the hypochlorite.) This will produce a strong “stock chlorine” solution of approximately 500 milligrams per liter, since the calcium hypochlorite has available chlorine equal to 70 percent of its weight. To disinfect water, add the chlorine solution in the ratio of 1 part chlorine solution to each 100 parts water to be treated. This is roughly equal to adding 1 pint (16 ounces) of stock chlorine to each 12.5 gallons of water to be disinfected.
Note: You must be absolutely certain to get the variety of pool shock that contains only calcium chlorite. The other types of chlorine, tri-chlor and di-chlor, are not suitable for this. Make sure that there are no antifungal or clarifier additives! Also, be advised that calcium hypochlorite is a powerful oxidizer, and should be stored in a dry container, sealed from moisture. It can also catch fire violently if put in contact with brake fluid and similar substances, so be careful.
With some planning, you should be able to distribute water-purification supplies as charity. Make some photocopies of directions for using hypochlorite tablets. If you distribute plastic ziplock bags of hypochlorite tablets (roughly six ounces per bag) along with direction sheets, you could save hundreds of lives in a public-health emergency such as a flood, or any other situation that disrupts utility water-distribution systems.
A Budget Water Filter: Constructing a Big Berky Clone
Every family should own a water filter. The problem is that high-volume ceramic filters such as the Big Berky are quite expensive. One considerably less expensive option is to make your own filter. In my experience, the field-expedient sand and clay filters touted by wilderness and bushcraft survival experts are effective only for use as a prefilter. Their output still has a brown-tinged pond-water look to it, and since the filter media is so coarse, they do not remove all harmful bacteria, so their output still has to be treated either chemically or by heating to 149 degrees Fahrenheit.
You can buy Berkefeld white ceramic-filter elements by themselves from a number of vendors including Ready Made Resources and Lehman’s. With these elements, you can build your own bargain-basement “Berky clone.” This consists of a pair of food-grade plastic buckets stacked one above the other. The top bucket has one or more holes drilled into it, to accept the Berky spare-filter elements. Each element by itself costs around forty dollars. To get