PURIFYING WATER

March 19, 2003

Water is the most important element in staying alive. It is essential that every person have enough and it must be safe to drink. Calculate 1 gallon (roughly 4 liters) DRINKING water per person per day as a rule of thumb. Needs differ according to age, physical condition, activity and environment. This does not include water for cooking, bathing or pets. If you have a medium-size dog, for example, plan at least another 1 gallon of water for each dog per day, 1 pint per day for each cat . W A T E R Assuming clean and deodorized food-grade containers are used, untreated water straight from your tap should keep 6 months, but MUST be changed thereafter.

Bacteria-free water, which means successful treatment by one of the accepted methods listed, will keep several years depending on heat, light, degradation of the container, etc.–Store your water away from paint and petroleum-based products, acids or anything releasing strong odors like fertilizer or household cleaners. While able to hold water, these lower grade containers are permeable to certain gases.—If you run out of stored water, you’ll need to locate an alternate source. Especially in times of disaster, assume any water not stored or purchased is contaminated. It could look like a crystal clear stream and still be polluted.

If the water you locate is brackish, first strain the debris through a paper towel, clean cloth or coffee filter. bring water to a rolling boil and maintain for a minimum of 10 minutes. For every 1000 feet above sea level, add one minute of boiling to the initial 10 minutes. If the water pot is covered, it will shorten the time to reach a boil. This method is recognized as the safest treatment.Then treat by one of the following methods. Ø -Boiling Water –

LIQUID CHLORINE BLEACH

Any brand – must be 5.25% or 6% sodium hypochlorite (like Ultra Clorox) and contain NO soap, fragrance or phosphates. Measuring by drops is more accurate and the preferred method.– 1 GALLON / 4 LITERS WATER –Add 16 drops (1/4 tsp. / 1.25ml) chlorine— 5 GALLONS / 19 LITERS WATER–Add 80 drops (1 tsp. / 5ml) chlorine

WATER PURIFICATION UPDATE

Clorox replaced their standard product with Ultra Clorox increasing the amount of sodium hypochlorite from a concentration of 5.25% to 6%. They have added sodium hydroxide, which they state does not pose a health risk for water treatment. Clorox made this change in order to reduce the size of their containers. It does not affect the amount of chlorine used to disinfect water. This is still the standard formula.

AMERICAN RED CROSS STANDARD

1. Filter water using a piece of cloth or a coffee filter to remove solid particles.

2. Bring water to a rolling boil for about one full minute.

3. Let it cool at least 30 minutes. Water must be cool or the chlorine treatment described above will be useless

4. Add the required amount of liquid chlorine bleach in the table above.

5. Let stand 30 minutes.

6. If it smells of chlorine, use it. If it does not have a chlorine scent, add 16 more drops of chlorine bleach per gallon of water (or 8 drops per 2-liter bottle of water), let stand 30 minutes, and smell it again. If it smells of chlorine, use it. If it does not, discard it and find another source of water.—-For storing water in 55 gallon drums, use 50ml or a scant 1/4 cup chlorine. Remember, these doses are for treated city water which has (or should) have a chlorine demand of zero. Field water will need more.

GET A TEST KIT

For free chlorine measurement so guess work is gone. Target treatment at 3-5ppm (parts per million) free chlorine for city water and 5ppm for field water. If bleach is more than one year old, it loses approximately 50% strength. In this case, the amount of bleach should be doubled. After treating with chlorine, mix well and allow water to stand 30 minutes before using. Use this eyedropper for no other purpose. If the bleach is not dated, at time of purchase, note the date on the bottle with a permanent marker

DRY CHLORINE Also called calcium hypochlorite has the added benefit of extended shelf life. Providing it is kept dry, cool and in an airtight container, it may be stored up to 10 years with minimal degradation. If one is wanting to keep chlorine in larger quantities, this is the item to store as it is readily available at swimming pool supply stores and many hardware and grocery stores carrying pool items and requires less actual storing space than its liquid counterpart.

For chlorinating water in rain tanks, Western Australia Health Dept. regulations state for first time chlorination, add 7 grams dry (1/4 ounce by weight) or 40ml (1.35 ounces) liquid per 1000 liters (264 gallons) and let stand for 24 hours before drinking.

To maintain adequate chlorination, on a weekly basis add 1 gram dry (.035 ounce by weight) or 4ml (.135 ounces) liquid per 1000 liters (264 gallons) of water. Let stand for two hours before drinking.

NOTE: Calcium hypochlorite is the solid form with 65% strength and sodium hypochlorite is the liquid form with strengths about 12.5%. Household bleach is sodium hypochlorite (NaHOCl) of about 5% strength. Most household bleach labels will read 5.25% or 6%*—IODINE – if no instructions are provided on the container, use 12 drops per gallon of water. If the water is in question, double the amount of iodine. Mix well and allow the water to stand 30 minutes before using

HYDROGEN PEROXIDE* – Peroxide is a perfectly acceptable disinfectant for water, as it oxidizes as does chlorine. There are a couple things with peroxide that make it differ from chlorine as a disinfectant. Peroxide degrades even more rapidly than chlorine and potency may be an issue if it is to be stored.

The other thing that makes peroxide more difficult to use is that testing for peroxide residual levels is difficult compared to testing for chlorine residuals. Residuals need to be measured to ensure disinfection is complete. This is dependent on the bacterial loading of your water source. There are various methods of testing for bacteriological levels, but measuring residual levels is much simpler. “Residual” is that which remains from the original dosage and has not unreacted (potentially to prevent reinfection). Example: if one cup of water has 20 parts per million ‘bugs’ in it, the disinfectant dosage needs to be at least 20ppm but no more than 25 to prevent ill effects.

A dosage of 23ppm (of the active chlorine component) will show a 3ppm free residual while showing a 23ppm total chlorine level (if the background is zero). Peroxide would potentially have the advantage of breaking down to oxygen and water, but its use is also made more difficult by that fact when measuring reacted components. A quick calculation to use daily is the required dosage in parts per million, times the volume treated in gallons, divided by 120,000 (which is a constant). This calculates the number of pounds needed to give that dosage. Unfortunately there is no simple answer.

PURIFICATION TABLETS – these tablets are either iodine or chlorine based. One or two tablets will purify one quart or one lit re of water depending on contamination of water and length of time allowed for treated water to stand. Follow instructions on the package. (Note: While economical and convenient, not every brand of purification tablet kills Giardia.)

STABILIZED OXYGEN – reports from people that have used this method feel it is more favorable than iodine and chlorine. Both iodine and chlorine have shown some side effects if used for an extended period of time and these treatments have a taste to them. Stabilized oxygen is neither harmful nor has a taste. Conversely, it has a number of health benefits.— For short-term water storage, treat 1 gallon of already-chlorinated water by adding 10 drops of stabilized oxygen. For water to be stored for long-term, add 20 drops. For 55 gallon drums, use 55 ml or 1,100 drops. Store in a cool location, away from direct sunllight.–To purify 8 oz. of Giardia-contaminated water, add 5 – 20 drops of stabilized oxygen. Let stand 2-1/2 minutes before consuming.

Since this water purification method is less known than the others, here are some chlorine dioxide (a form of stabilized oxygen) products on the market: Aerox, Genesis 1000, Dynamo 2, Aerobic Stabilized Oxygen (formerly Aerobic 07), Aquagen. We are not endorsing nor recommending any of these products; they are sources you may

WATER PURIFYING UNITS – there are a number of water purifying units on the market. Before purchasing a purifier, there are several things to consider, durability/reliability (will parts break down with heavy usage?), how easy is the unit to pump, how much water output can you expect in a half hour, will this particular unit filter giardia and other bacterial agents, does it still work in brackish water, cost and availability of additional filters. For an overall excellent article on water contaminants, check SweetWater’s

FAQ.— If portable water purifiers are a new product to you, Byron Kirkwood of BA Products has written an informative article about the basics. It lists features to compare and gives an overview of two of the four brands listed below. –For Katadyn Water, MSR Purifier, Pur, British Berkefeld, or Sweetwater Purifiers: BA Products Back Country Store Cabela’s Caribou Cry Outdoor Store Epicenter Northern Mountain Outback Gear Pur REI South Summit Corp Walkabout Travel Gear Walton Feed Wildware Outfitters TIP: To improve the taste of any treated water, pour water from one clean container to another several times. This will help re-oxygenate the water and remove its flat taste after treatment and storage.

Adding powdered drinks like Kool-Aid or Tang will help disguise any off-tastes in water. These two products are also good sources of Vitamin C. Instead of using powdered drinks, a pinch of salt per quart can improve treated water’s flavor

WINE-TREATED WATER – from digesting many romance novels over the years, I remembered reading about watered wine. While thinking “watered” wine did not sound terribly appetizing to adults, it was also fed to children. This made me wonder if there had been water shortages or was the water too unpalatable to drink.–. Olive oil has many interesting uses and excellent reasons for storing it. Among its versatile applications are fuel and lamp oil, treatment for burns and ulcers, soothing wounds, cooking and salad dressings; and anointing in religious ceremonies. Today it is also connected to reduction of breast cancer and heart disease. —Since ancient times, in countries like Israel, Rome and (more recently) France, water was too polluted to drink untreated. By mixing 1 part red wine to 3 parts water, sufficient purification was achieved. For killing bacteria in laboratory conditions, red wine ranked 3 to 4 times more effective than pure alcohol or tequila. The effective ingredient is believed to be phenol compounds enhanced from charred wood of the wine-aging casks. This is important because phenol compounds appear to be related to sulfur drugs previously used in basic antibiotics. (Source: Dr. Trichopolou, British Medical Journal discussing the Greek Villager’s Diet.) The full article is here. Do not assume this method kills Giardia and Cryptosporidia, etc. View this treatment as secondary measures only.

USING SWIMMING POOL WATER – View your pool as “backup” water. Keep it treated; you never know when this water will be needed! Maintenance of the free chlorine residual will prevent establishment of any microorganisms. Maintenance levels should be kept to 3-5ppm free chlorine. To monitor this, you’ll need a supply of chlorine testers. The problem with using swimming pools is that organics can enter through dirt, sweat, body oils and the inevitable kiddie tinkle. This can form chloramines which are not good to drink. Of course in a survival situation it’s OK, but steps can be taken to minimize this.—Partial and complete water changes should be done when possible. Although impossible to make a general rule, change pool water at least 1-2 times a year and make partial changes after heavy use. In a sealed drum, water can stay good for years, but we still recommend changing it at least once a year. Now imagine going in and out of your drinking water a hundred times and then drinking it. Don’t let clarity fool you, some crystal clear mountain springs have tested out to be laced with cholera.—Keep dry chlorine on hand as it has a much longer shelf life than liquid. Additionally, when the need arises to convert a pool to potable water, it’s obviously too late to completely change the water. However, the residual chlorine should be elevated over 5ppm up to ten parts, then allowed to naturally dissipate. This should take a couple of days and ensure that any of the more tenacious bacteria is destroyed. If other stored water stocks are not available, remove— the necessary pool water and boil it or just treat with chlorine to the normal 5ppm. It is best to err on the side of caution.–When adding solid chlorine, dissolve the granules in a bucket first, then add to the pool water; much better mixing will result. Without power, a clean paddle or oar should be designated as a mixer. Thirty minutes minimum contact time is needed before use, more if temperatures are cold or if mixing is poor.

For smaller amounts of water, if you still have power, boiling is a reliable treatment. However, boiling water is not an efficient use of fuel if it’s scarce. Bear in mind, while boiling pool water is fine, boiling alone will not prevent re-infection from airborne contamination. Once water is boiled, a lower chlorine residual of 3ppm free is OK.–Make sure to store an adequate supply of pH balancers and available chlorine testers if you intend on drinking pool water. Chlorine loses effectiveness above 7.5pH; that’s why pH control is important. Bromine chemistry will do the job in the higher pH ranges, but it’s not approved for potable water. Use bromine disinfection for washing dishes, laundry, clothes and people.–You might consider a filtration system that removes the chlorine taste. Activated carbon in any form will remove chlorine, but remember, once you remove the free chlorine, your water does not have any protection. It should be consumed immediately following chlorine removal.–In a pinch, highly chlorinated water can be trickled through the ashes from a fire that are suspended in a cloth or coffee filter or even a cut-off pants leg tied at the bottom, that will prevent ash from passing through while allowing the water to pass.–Covering the pool at all times when not in use is a very good idea; try to keep the cover clean and wash the area you put it on when removing it from the pool.

DISTILLED WATER* – Distilled water comes from steam and recondenses to liquid form. The purity of the steam and the temperature at which this occurs would make drinkable water as is. Problems arise when it comes in contact with air, dust, spores or whatever else that could be in, on, or about the container. Theoretically, if steam were produced and cooled and the condensate then put directly into a sealed sterile container, there would be no problem. Storage would require no chlorine. The argument could also be made that even if bacteria got into the condensate, what would it eat? Biological organisms require carbon, nitrogen and phosphorous to survive at all so the chances of having a problem are slim to none.

To be extra safe, treat it just to nip any potential contamination in the bud. If the container were near sterile and the process done in a clean and sealed manner, it would probably be fine. Chlorine or other purifying agent required would be absolutely minimal. For example, if typically 8 drops of chlorine per gallon is used, one would suffice. Chances are very minute that there would be a problem, but it’s best to avoid even minimal risk.—As for the electric distiller, the only possible contamination of the condensate would be from chemicals that will volatilize due to the increased temperature. Again, the risk is probably in the 1%-2% range. If this is a concern from conducting a land survey for potential aquifer contaminants like agriculture or industry, then a carbon filter placed before the distiller will reduce the chances to near zero. Many typical water contaminants show inverse solubility with temperature and will have a tendency to form scale deposits in the heating chamber of the apparatus. There will be more problems with things staying in than going out! As the steam leaves, water contaminants will become more concentrated and the tendency to deposit will increase. This type of (primarily) mineral deposits can be removed by cleaning with a low pH (acidic) solution to dissolve them. The stuff found in water is good for us and by distilling it, you will remove a source of minerals and trace minerals. Interestingly, distilled water is a relatively poor conductor of electricity.

To sum it up, distilled water is pure and safe to store, but there are small areas of potential problems.

Comment on purchasing distilled water from the grocery store – those jugs degrade! When boating in Colorado, we used to keep distilled water of board for the batteries. If they weren’t used in one season, the unopened jugs were stored in the basement in an undisturbed corner. One day I went down to that area of the basement and noticed a rather large area of wet floor wet. Picking up one of the gallon jugs, I saw fine holes all over the container like it had rubbed a porcupine. The jugs were about six months old and in the process of totally breaking down. If you’re planning to use this water for storage, the container definitely has a “shelf life”! Also, if you plan on transferring the distilled water to another container, you risk airborne contamination unless chlorine is added.– Taste: before purchasing a lot of distilled water for drinking, you may want to try it first. Distilled water has a very flat, uninteresting taste. Check and see it makes your palate happy.—*Information on Hydrogen Peroxide and Distilled Water kindly provided by Robert Byrnes, degreed Chemist with Nalco Chemical Company and eight years as a Water Treatment Specialist with the US Army

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