Last month we discussed a few techniques to use to purify water including boiling and pasteurization using a WAPI in our Sun Oven®. This month we’re including more options. Some techniques will not work for everyone, but this way, you’ll have lots more options. The one thing to understand is that water is water. What makes it safe or not are the contaminants in it. Contaminants include:
- Particulates – suspended material that makes water look cloudy. Can be organic or inorganic matter.
- Microbiological – usually living organisms including bacteria, viruses, parasites, etc. These organizsms can cause serious illness or death.
- Heavy Metals – these inorganic contaminants include toxic chemicals like arsenic, flouride, lead, mercury, and nitrates. These are toxic and have been linked to birth defects, brain and nerve damage as well as cancer.
- Radioactive materials – include minerals that are unstable on the atomic level. As they decay, atomic nuclei break down into smaller particles emitting charged particles and releasing energy. Sometimes these particles pass through living cells without causing damage. Other times they may strike DNA (genetic material) which may cause damage resulting in new cells that have growth problems. Cancer is a big cell growth problem.
- Petrochemicals – include carbon-based, (organic) petroleum contaminants such as gasoline, solvents, pesticides and herbicides.
Water in different places have a different group of contaminants depending on the current environment and emergency sitiuation. Some are more dangerous than others. Here are some ways to de-contaminate water.
- Use unscented household bleach (5.25% sodium hypochlorite). Here are some examples: 1 gallon is disinfected by 8-16 drops (1/4 teaspoon), 1 Tsp will disinfect 5 gallons; 8 oz (1 cup) for a 55 gallon drum. Bleach solutions degrade over time (~2%per month). So bleach solutions don’t store well. What to do?
- Use Calcium Hypochlorite instead. It is available for purchase as a dry, granular powder. Calcium Hypochlorite is widely available for use as swimming pool chlorine tablets or white powder that is much more stable than bleach. This is often known as “pool shock”. Look for powder not having blue dye added. Using granular calcium hypochlorite to disinfect water is a two step process. Make a stock solution of chlorine solution (do not drink this!) by dissolving 1 heaping teaspoon (about one-quarter of an ounce) of high-test (78%) granular calcium hypochlorite for each two gallons (eight liters) of water. To disinfect water add one part of the chlorine solution to 100 parts water to be treated. Let the mixture sit for at least one-half hour before drinking. Another plus for using calcium hypochlorite to disinfect water for emergency use is that a little goes a very long way. A 1-pound bag of calcium hypochlorite in granular form typically costs only a few US dollars and can be obtained in any swimming pool supply section of your hardware store or online. This amount will treat up to 10,000 gallons of drinking water, which is enough for a family of four for some six or seven years at a gallon per day per person! Calcium hypochlorite will store for a long period of time and remain effective as a chemical drinking water treatment. It lasts far longer and treats far more water than the traditional chlorine bleach water disinfection treatment.  No matter what form of chlorine you decide to use, please remember to use it with caution and keep it out of the reach of children. Chlorine is very poisonous when it isn’t used properly. Use caution and wear proper breathing, eye, and skin protection when handling.
- Distillation – This is a process where boiled water turns to steam. The steam is captured and condenses as it cools and is collected into a clean container. The process kills most disease-causing microbes and eliminates most chemical contaminants. Distillation will remove most radioactive uranium and also lead from drinking water.[4, 5] In most cases distillation separates the good water from bad contaminants. The Survival Still is a good example of a distillation unit that can be used during an emergency to prepare pure water. The first three techniques mentioned here are those most recommended by the American Red Cross.
- Ultraviolet radiation – uses ultraviolet light to purify water. This process destroys 99.9% bacteria, viruses, and protozoa without using harmful chemicals and without changing the taste, odor or color of the water. One of the largest manufacturers is SteriPEN . Their products are small and can purify up to 2,000 gallons (8,000 liters) of water. The potential downside is that they require a power source, so you will need a supply of proper sized batteries or other source for that power. The SODIS Method stands for solar water disinfection. It’s amazingly simple. Put water into a PET rated plastic bottle (recycle code #1), lay it in the sun for at least 6 hours and you have safer water to drink thanks to the ultraviolet radiation. Please note that you may need to filter cloudy water before using this method and if the weather is overcast, 2 days will be required to purify the water. But it is FREE and requires no additional energy source except the sun.
- Filtration Systems – From whole house systems to individual portable units, filtration can be one of the best ways to remove unwanted minerals from any kind of water. Without electricity, reverse osmosis systems will not function properly. Carbon block filters (like the ones in the Berkey System) are the next best option for removing sediment. The more sediment, the more frequently the filters will need to be changed. These gravity fed filters do not require a source of power to clean the water. Free-standing filtered water systems like the Berkey Light hold 2.75 gallons of water purified and ready to drink right on your kitchen counter. Originally designed to keep Queen Victoria and her royal family safe from the Cholera and Typhoid outbreaks that ran rampant in the early 1800’s, a lot of thought and effort was put into the development of this purification system. Ultra powerful, the purifying elements are able to eliminate 99.9999999% of all bacterial pathogens from contaminated water. This filter will remove pesticides, herbicides, volatile organic compounds, viruses, Radon 222, parasites, heavy metals, chemicals, trihalomethanes. Scrub the filters with a ScotchBright® pad to clean the element and it is ready to use again.
- Portable water filters – some examples include:
Sawyer water filter technology was derived from kidney dialysis, these hollow fiber membrane units have been designed to extreme filtration 100% of the time to ensure no bacteria would get through.
Lifestraw is one of the world’s most trusted portable water filters. These are used in both emergencies and as a daily source of drinking water in third world countries. You can never carry enough water (at 9 lbs. per gallon) you know what I mean. This filter will provide up to 1000 liters of safe drinking water instantly.
Katadyn makes a series of filters for campers and hikers (and bug-outers) that are light weight and offer pure water for groups as well as individuals.
- Solar Distilling – for the back to really, really basics, dig a hold or pit in the ground. Place a container in the center of the pit; cover the hole with transparent plastic and secure it tightly. Place a pebble on the center of the plastic. Water from soil will evaporate and condense on plastic and drip into container. Be patient.
Billie Nicholson, Editor