One thing no one wants to go without is water – clean
and fresh H2O. Whether you’re out backpacking or in the midst of a disaster, access to clean water is imperative. Here’s how to make sure you’re never without.
Chemical Purification
Many chemical purification systems are used in industry, and in municipal water supplies. It’s a cheap way to purify water, but it’s not without its downsides.
Chlorine – Chlorine is a common and cheap chemical, but it’s extremely toxic. It doesn’t decrease physical or chemical contamination, but it does kill biologicals. It’s also implicated in increasing cholesterol levels, is a carcinogen, and is known to cause heart disease.
Bromine – Bromine is usually used in pools and spas. It’s a weak disinfectant, and doesn’t kill bacteria very well.
Iodine – Iodine is useful when camping, because it provides a campers with an easy way to treat water that’s cheap and effective. Best of all, it’s consistent. Biological contamination can be neutralized consistently. However, iodine does not remove chemical and physical contamination.
Hydrogen peroxide – HP is very effective at killing bacteria and viruses using oxygen. However, it can be highly toxic. It’s used mostly in emergency situations when no other water purification methods are available.
Silver – Silver is an effective bacteriocide, but it’s also a poison which can accumulate in the body.
Organic acids – Non-toxic organic acids should only be used in larger water plants. They are not suitable for home use.
Lime and alkaline agents – These agents are not typically used by consumers due to their extreme toxicity.
Ion exchange – Ion exchange is a process where sodium from salt is exchanged for calcium or magnesium. It uses a glauconite, precipitated synthetic organic resins, or gel zeolite, all of which softens the water. The end result is that minerals, metals, and chemical odors remain unaffected and the water is salty to drink.
Filtration Techniques
Filtration devices are a staple in many households and one of the best ways to treat contaminated water. While most filtration devices filter only limited chemical contaminants, some filter biological, physical contaminants, and radiological waste.
Slow sand – A one cubic meter block of slow sand will filter 2 liters per minute of water, but it is a poor medium for filtering bacteria.
Pressure sand – Pressure sand uses one cubic meter of sand which passes 40 gallons per minute. It must be back-washed daily to prevent clogging.
Diatomaceous earth – DE removes suspended particles at high and low flow rates, but it must be back-washed daily and is expensive to replace.
Porous stone – Porous stone and ceramic filters are small and expensive, and they typically will not filter chemical or biological contaminants. However, they are very good at filtering physical contaminants. These types of filters are often combined with other filter media to enhance the filtration properties since ceramic tends to be very sturdy material.
Charcoal – Charcoal is the best type of filter if you need to remove chemicals and lead, but it is easily clogged and must be used with sediment pre filter.
Reverse osmosis – RO machines use a membrane with microscopic holes that require 4 to 8 times the volume of water processed in order to remove contaminants. RO machines may or may not remove chemicals and bacteria, depending on the media and membranes used.
In the history of water purification, RO machines stand out because they were some of the most successful kinds of filtration devices ever made for physical contaminants.
Oxidation Strategies
Of the three main methods of purifying water, oxidation is the least understood and the most expensive.
Aeration – Aeration techniques sprays water into the air to raise the oxygen concentration in the water. It does break down odors, and balances dissolved gases, but it also takes a lot of space to do this, and it’s expensive. On top of that, it picks up contaminants from the air. So, it’s not recommended for home use.
Ozone – Ozone is a good bactericide, it uses highly charged oxygen molecules to kill bacteria on contact, and it oxidized other contaminants and flocculates iron, manganese, and other kinds of dissolved minerals. This is a good method for purification, but it’s also very expensive for most people to use.
Electronic purification – This method creates a super-oxygenated environment in the water which kills bacteria, viruses, and reduces surface tension, effectively treating all types of contamination. These types of systems tend to be for commercial operations, and their expense makes it cost-prohibitive for most consumers.
Jeremiah Allen is a co-founder of FatPrepper, an emergency preparedness and survival blog that aims to provide useful information for people who work to be prepared for any situation
This article first appeared on American Preppers Network and may be copied under the following creative commons license. All links and images including the CC logo must remain intact.
