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Purify or Filter Water

  1. Water Conservation Games and Activities (Environmental Protection Agency)
      Provides 11 games and activities to help children better understand how water is purified and used, as well as facts about water. 1-01

  1. -Natural Ways to Purify or Clean Water (
      Provides dozens of articles. 02-10

  2. Biochar for Removing Phosphate from Water (
      "In the study, researchers started by collecting solid residues left after beet tailings were fermented in a device called an anaerobic digester, which yields methane gas. The material was baked at about 1,100 degrees Fahrenheit to make biochar."

      "The biochar was added to a water-and-phosphate solution and mixed for 24 hours. It removed about three-fourths of the phosphate, much better results than researchers obtained with other compounds, including commercial water-treatment materials. The phosphate-laden biochar can be applied directly to soils as a slow-release fertilizer." 03-12

  3. Bleach Treatment for Purifying Household Water (
      "Unscented household bleach with 5% chlorine can sometimes be a good disinfectant. For example, this may work when the water is not heavily polluted, or when Giardia or cryptosporidiosis are not a concern."

      "Bleach does not work well in killing off Giardia or beaver fever or Cryptosporidium parasites. The amount of bleach needed to kill these parasites makes the water almost impossible to drink. If Cryptosporidium or Giardia are in your water, boiling is the best way to ensure safe drinking water."

      "Disinfection using bleach works best with warm water. Add 1 drop (0.05 mL) of bleach to 1 Litre [33.8 fluid ounces] of water, shake and allow to stand for at least 30 minutes before drinking. Double the amount of bleach for cloudy water or for cooler water. A slight chlorine odour should still be noticeable at the end of the 30-minute waiting period if you have added enough bleach. The longer the water is left to stand after adding bleach, the more effective the disinfection process will be."

      "If you are treating water from a lake, stream or shallow well, use twice as much household (5%) bleach as indicated in the chart below and wait twice as long before drinking it because it is more likely to contain chlorine-resistant parasites from animal droppings."

      "Let the water stand for at least an hour after adding the bleach before you start drinking it. If the water is colder than 10°C [50 degrees Fahrenheit] or has a pH higher than 8, let the water stand for at least two hours before drinking." 10-07

  4. Bleach Treatment for Purifying Household Water (
      "If you can't boil water, you can disinfect it using [unscented] household [chlorine] bleach. Bleach will kill some, but not all, types of disease-causing organisms that may be in the water. If the water is cloudy, filter it through clean cloths or allow it to settle, and draw off the clear water for disinfection. Add 1/8 teaspoon (or 8 drops) of regular, unscented, liquid household bleach for each gallon of water, stir it well and let it stand for 30 minutes before you use it. Store disinfected water in clean containers with covers." 10-07

  5. Boiling for Purifying Household Water (
      "Boiling is the best way to kill bacteria, viruses and parasites. A full boil for at least one minute is recommended. At elevations over 2,000 meters (6,500 feet) you should boil water for at least two minutes to disinfect it. NOTE: This is not appropriate for water that is heavily polluted or subject to chemical contamination." 10-07

  6. Iodine Treatment for Purifying Household Water (
      "Whenever possible use warm water (20°C) and let stand a minimum of 20 minutes after mixing and before drinking. For cold water (5 - 15°C) increase the waiting time after mixing to 40 minutes. If you are using 2% tincture of iodine, use 10 drops (0.5 mL) for every one litre [33.8 fluid ounces] of water. With iodine tablets, follow the manufacturer's directions."

      "Note: Pregnant women should not use iodine drops to purify water as it may have an effect on the fetus. Iodine should not be used to disinfect water over long periods of time as prolonged use can cause thyroid problems." 10-07

  7. Large Water Filters and Purifiers (
      Provides water filters and purifiers. Awesome Library does not endorse these products, but provides them as examples. 03-06

  8. Microbe Attacks Water Pollution (CBS News)
      "An industrial chemical that pollutes groundwater and has resisted cleanup can be neutralized by an obscure microbe that researchers have discovered in the Hudson River bottom mud."

      "In a study appearing Friday in the journal Science, researchers at Michigan State University report a previously unknown bacteria is able to turn trichloroethane, an industrial chemical that is difficult to clear from ground water, into a more benign compound that other microbes can render harmless." 9-03

  9. Nature's Water Cleaners: Mussels (National Geographic)
      "One mussel alone can cleanse as much as a gallon of water per hour. Add up the work of a whole mussel community, and you get a virtual water treatment plant."

      "According to Ethan Nedeau, an expert on the freshwater mussels of New England, even half the population of mussels at work in a one-half mile segment of New Hampshire’s Ashuelot River can help cleanse more than 11.2 million gallons of water a day–roughly the quantity of household water used by 112,000 people." 07-12

  10. Ozone Treatment: How It Works (
      "Ozone is second only to fluorine as the most powerful oxidant. Ozone inactivates and oxidizes organic metals and most organisms faster than chlorine. Ozone also functions as a micro flocculating agent to 'polish' the water and improve clarity (clarifying iron, sulfur and manganese)." 10-07

  11. Purifying Water (How Things Work)
      Provides directions on purifying water, including desalination. 03-06

  12. Water Distillers: A Guide (WholesaleWaterDistillers)
      Suggests what to look for in a water distiller. 04-08

  1. -Filtering Water With LifeStraw (Wall Street Journal)
      The light blue straw with a resilient polystyrene shell looks like a child's musical recorder. When someone sucks through the straw, the water flows through textile and iodine filters, which kill off viruses and bacteria such as E. coli."

      "The company says nongovernmental organizations and nonprofit agencies already have bought hundreds of thousands of the drinking tubes and are distributing them in countries with unsafe drinking water."

      Awesome Library does not endorse these products but provides them as examples. 07-07

  2. -Is Graphene the Perfect Water Filter? (
      "Graphene - a thin sheet of carbon atoms - along with its cousin, the carbon nanotube, is one of the most promising materials discovered in a long time. It has superlative properties when it comes to strength, thinness, conductivity, optics, etc. We know a lot about, but scientists and engineers are still finding new ways to use it. The latest discovery has to do with a property of graphene that makes it superpermeable with respect to water."

      "This should allow graphene to be used to purify water, removing everything else from it and thus making it drinkable."

      Editor's Note: Minerals, presumably, would need to be added to the water supply to make it drinkable long-term. 05-12

  3. Water Problems (
      "We now know the symptoms, the cause of the symptoms, and how to cure the problem itself. Sometimes the symptoms are easy to read and easy to cure. Other times, several problems exist in the water at the same time. Then it gets more complicated, and usually more costly to correct." 07-08

Purchase Resources
  1. Chlorine Dioxide Tablets for Purifing Water (
      Costs around $13 for 30 tablets. "Features the same proven technology used in municipal water supplies; effective against viruses, bacteria, giardia and cryptosporidium."

      "Meets U.S. EPA purification guidelines; might take as long as four hours to kill contaminants in extreme situations." 10-07

  2. Filter: Katadyn Pocket Water Filter (
      Costs around $220. "You can buy good cheaper filters, but you will end up paying more on all the replacement filters to pump the same amount as this will pump with one. Consider that it filters down to .2 microns while others only filter to .3 then add in the quality construction and lifetime warranty. If this is not the filter in your backpack, your research leads you to a much different conclusion than ours did. If you come across water that you are concerned may contain viruses they don't live long carry some Katadyn micropur tablets. Pump is fast and easy to use!"

      This filter does not remove or kill viruses. Awesome Library does not endorse these products, but provides them as examples. 10-07

  3. Flouride Filters (
      "Fluoride (F+) is a common constituent of many minerals. Municipal water treatment plants commonly add fluoride to the water for various reasons, one of them common belief in prevention of tooth decay. Water fluoridation is controversial, and Fluoride is considered to be a poison in all but one European country. Concentrations above 5 mg/l are detrimental to tooth structure." 10-07

  4. Iodinated Resin: Katadyn Exstream Purifier Water Purifier (
      Costs around $45. "First-stage Filter removes large sediment and disagreeable odors"

      "Second-stage Cyst Filter traps protozoa in a web of glass-fiber"

      "Third-stage EPA registered ViruStat Microbial Cartridge disinfects the water from bacteria and viruses with iodinated resin."

      Awesome Library does not endorse these products, but provides them as examples. 03-06

  5. Ozone Treatment for Purifying Household Water (
      "Now you can have safer, good-tasting, chemical-free, lead-free water at the convenience of your kitchen sink." 10-07

  6. Ultraviolet Light Disinfection (
      "Ultra is the most advanced UV water purifier in the world."

      "Rechargeable and easy to use, the smiley face tells you when the water is safe to drink. Great for adventure and business travel."

  7. Ultraviolet Light Disinfection: Water Line Version (
      "Canadian-made Trojan UVMax effectively purifies your water, protecting you against viruses, bacteria, and intestinal protozoa such as Cryptosporidium and Giardia." 10-07

  8. Ultraviolet Light: SteriPEN Adventurer Water Purifier (
      Costs around $150. "Requires no pumping, chemicals, test strips, extended time-keeping or filters; leaves no aftertaste, will not clog and does not require lubrication"

      "Innovative SteriPEN system uses UV light rays instead of chemicals to purify water for drinking"

      "Ultraviolet (UV-C) light rays safely sterilize clear water by destroying protozoa (including Giardia and Cryptosporidium), bacteria and even viruses"

      "SteriPEN Adventurer is simple to use: Just press a button and gently agitate the water with a quick stir"

      "Purifies 16 fl. oz. of water (cold or warm) in less than a minute, or 32 fl. oz. in a minute and a half"

      "Small size fits most containers—use it in cups, mugs, water bottles and canteens"

      "Carries easily in a shirt pocket"

      "Solar battery charger also acts as a carrying case."

      Awesome Library does not endorse these products, but provides them as examples. 10-07

  9. Water Distillers (
      Provides countertop steam-distilled water. Nutriteam offers the product for $119. Awesome Library does not endorse this product but provides it as an example. 04-08

  10. Water Distillers (
      Provides countertop steam-distilled water for $99. Awesome Library does not endorse this product but provides it as an example. 04-08

  11. Water Distillers: Non-Electric (
      Provides stove or fire-based distiller for $289. Capacity is 16 gallons per day. Awesome Library does not endorse this product but provides it as an example. 04-08

  12. Water Magnets (
      Provides magnets designed to neutralize minerals and salts in water to reduce buildup in appliances and/or for cleaner clothes or hair. Awesome Library does not endorse this product but provides it as an example. 04-08

  13. Water Purifiers (
      Provides water purifiers and filters. Explains the advantages of each. Awesome Library does not endorse these products, but provides them as examples. 03-06

  1. 09-04-03 Dean Kamen Invents Water Purifier (
      " 'In the emerging world, in the under-developed world, a gallon of water is so precious that without it, you're going to die,' he says. 'In some places, the average amount of time per day spent looking for water that's safe for their kids by women is four hours. And they carry this stuff, which weighs 62 pounds per cubic foot, four or five miles. And if it didn't turn out to be the right stuff, or they put their hands in it and contaminated it, they spend the next day or two burying the babies.' "

      "Kamen began experimenting with a Stirling engine. The Stirling engine is named after its designer, Robert Stirling, a 19th Century Scottish minister. Basically, it is non-polluting device that plays heat against cold to create energy. It is a closed box with two chambers, one filled with gas."

      "When the gas chamber is heated from the outside, with anything from burning wood chips to charcoal, the gas expands, creating pressure. That pressure drives a piston from the hot chamber into the cool chamber. In Kamen's design, that mechanical power achieves two goals: it creates electrical power, 300 continuous watts – enough to run a few electrical devices - and, as a bonus, creates enough heat to distill contaminated water, making it drinkable." 9-03


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