Treating Water For Purification

Human health and water quality have always been closely linked throughout history.  It is now understood that fecal-borne bacteria, viruses, and protozoans are responsible for most water-borne diseases. If you are unsure of the safety and purity of the water before using it for drinking you should treat it.  Always strain the water through a cheese cloth or clean linen, water sock, paper towels, or coffee filters to remove any particles.  Then treat it in one of the following ways:

Boil vigorously for 10-12 minutes, or

Add liquid chlorine bleach (never use color safe or scented bleach).  The amount of bleach used depends upon how strong the active ingredient of sodium hypochlorite is.  Clorox Liquid Bleach uses a 6% ratio of sodium hypochlorite and has been thoroughly tested for water purification for drinking purposes.  Use:

• 4 drops per quart
• 16 drops per gallon
• 80 drops per 5 gallons

ALWAYS allow the treated water to stand for 30 minutes before drinking.  Properly treated water should have a slight chlorine odor.  If not, you may repeat the dosage and let stand an additional 15 minutes.  Chlorine dissipates somewhat as it sits.  You can also agitate the water or pour it back and forth between two containers to help the chlorine dissipate.  For further information on disinfecting water using Clorox Liquid Bleach, call 1-800-292-2200.

Add dry chlorine (swimming pool chlorine)

Very little dry chlorine is needed to purify water.  For one gallon, add just 1/8 teaspoon of dry chlorine.  Mix well and let water sit for 24 hours with the lid or cap ajar.  Once again, chlorine dissipates as it sits.  Because dry chlorine is so potent, you should test the water before drinking.  High levels of chlorine intake can make you ill and can even be fatal.  If you store dry chlorine and plan to use it to purify water for drinking, store chlorine test strips.  After adding the initial dosage of chlorine, let the water sit for 24 hours before testing using a chlorine test strip.

If chlorine is indicated on the test strip this means that living organisms have been killed and excess chlorine is in the water.  Allow the water to sit for another 12-24 hours for chlorine to dissipate before drinking.

If no chlorine is indicated on the test strip this means that the chlorine was used up killing organisms and there may still be more living organisms in the water.  Add another 1/8 teaspoon of dry chlorine to the water and again let it sit for 12-24 hours before retesting.  Repeat this process until chlorine levels are left in the water.  Allow the water to sit another 12-24 hours for chlorine to dissipate before drinking.

Dry chlorine and chlorine test strips can be purchased at any swimming pool supply store and are very inexpensive.  One pound of dry chlorine will purify hundreds of gallons of water.

Please note that a good water filtration system will filter out chlorine.  However, people often make two mistakes:

1. The water must sit for a period of time after the chlorine is added for the chlorine to kill the living organisms (in other words, don’t run the water through your filter too soon).
2. Do NOT add more bleach than necessary simply because you plan to run your water through your filtration system to remove it.  You don’t want to clog up your filters with chlorine.  Remember, it is not necessary to run the water through your filter because the chlorine will dissipate over time making the water safe to drink.

Pasteurize the water

Contrary to what many people believe, it is not necessary to boil water to make it safe to drink.  Heating water to 149 F for a minimum of 6 minutes, or to a higher temperature for a shorter time, will kill all germs, viruses, and parasites.  This process is called pasteurization.  What is the difference between sterilization and pasteurization?  Sterilization kills all of the organisms in the water, while pasteurization kills only those organisms that can cause harm to humans.  The following common disease organisms are killed by pasteurization:  Giardia, cryptosporidium, entamoeba, the eggs of worms, cholera, shigella, salmonella bacteria and those that cause typhoid, the enterotoxogenic strains of E. Coli, Hepatitis A, and also rotavirus which is a major cause of disease in children.  If using solar energy to heat the water, then using a Water Pasteurization Indicator (WAPI) helps you know when it is ready. The WAPI is a clear plastic tube partially filled with a soybean wax that melts at about  158 F.  With the solid wax at the top end of the tube, the WAPI is placed in the bottom of a black container of water that is solar heated.  If the wax melts and falls to the bottom of the tube, it ensures that water pasteurization conditions have been reached.  The WAPI has a stainless steel washer around it to keep it at the bottom of the container, which is the coolest location when solar heating water.  Since top water temperatures are often hotter than bottom water temperatures, lower WAPI placement helps to further insure that pasteurization conditions have been achieved. 

Water Filter System

Portable water filter systems are used to obtain drinking water from untreated sources.  The objective of these systems is to make un-chlorinated water safe for drinking.  Because we don’t have control over the animal world when it comes to our natural water sources, we MUST filter it!  Streams and springs may be contaminated by animal waste.  It is not uncommon for there to be dead animals upstream.  Giardia and Cryptosporidium, both of which cause diarrhea, are common in the United States.  Activated charcoal and ceramic filters do a good job of cleaning the water and making it suitable for drinking.  There are many good portable water filtration systems on the market.  Most will filter the bacteria at 99.99%.  Prices vary according to size, weight, functions, etc.  Find the one that is most suitable for your family’s needs.