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Water Filtration vs. Purification

In my early years of training raft guides I had a trainee take off his helmet in an eddy and proceed to take a huge gulp of river water. He did not seem to notice the dead calf in the eddy immediately upstream. The whole situation made me and another boat crew want to vomit in unison. The moral of the story, you never know what critter did what upstream of you. From that day on I have carried some sort of filter system.

Filtration and water purification are two methods used to remove contaminants and impurities from water. While both processes can improve the quality of water, they work in different ways and are used for different purposes.

Filtration is the process of separating solid particles from water by running it through a filter. Filters can be made of a variety of materials, including paper, cloth, sand, and carbon. The size of the pores in the filter determines which particles will be removed, so the smaller the pores the smaller the particles it will remove. Filters can be used to remove a wide range of contaminants, including dirt, sediment, bacteria, and viruses.

Water purification is a very different process which involves the use of chemical or physical processes to remove contaminants from water. These methods can be used to remove a wider range of contaminants than filtration alone, including heavy metals, chemicals, and other contaminants that are not removed by filtration.

One common method of water purification is to use iodine tablets or chlorine. Chlorination, which involves the addition of chlorine to water to kill bacteria and other microorganisms. Chlorine is a powerful disinfectant that is effective at killing a wide range of microorganisms, but it can also produce potentially harmful by-products if used improperly.

Another method of water purification is distillation, which involves boiling water and collecting the vapor that is produced. The vapor is then cooled and condensed back into a liquid, which is pure and free of contaminants. Distillation is effective at removing a wide range of contaminants, including bacteria, viruses, and most chemicals. However, it is a time-consuming process and requires a lot of energy to produce purified water.

Reverse osmosis is another method of water purification that involves forcing water through a membrane that removes contaminants. The membrane is designed to allow only water molecules to pass through, while larger contaminants are left behind. Reverse osmosis is effective at removing a wide range of contaminants, including bacteria, viruses, and most chemicals. However, the equipment involved in this process can be expensive to produce purified water.

Common Waterborne Illnesses

Water-borne diseases may be mistaken for the flu or food poisoning. In any case outdoor adventurers should avoid drinking unfiltered water at all times, but especially on remote multi day trips. These illnesses can quickly turn into a serious medical emergency in austere environments.

Giardia – The illness Giardiasis is caused not by a protozoan parasite known as Giardia Lamblia. According to the University of Missouri: “Giardia organisms form a resistant cyst that is shed by the host in its waste. Infections are acquired by ingesting these cysts in food and water or by personal contact with an infected person. Individuals exposed to Giardiasis respond differently. After parasite ingestion, the symptoms may take one to four weeks to appear. The number of cysts consumed is not related to the persistence or severity of the infection. As few as 10 cysts have been known to cause infections.”

E.Coli - Escherichia coli, is a specific genus and species of bacteria. E. coli is the predominant fecal coliform bacteria found in the gut of warm-blooded animals. According to the University of Georgia “While E. coli by itself is not generally a cause for alarm, it indicates the potential presence of other dangerous pathogens of fecal origin that are health threats, such as Salmonella, Shigella and others. Non-bacterial pathogens that may be present with fecal material include protozoans, such as Cryptosporidium and Giardia”

Cryptosporidium – Also known as Crypto, this microscopic parasite is incased by a shell which allows it to live outside the body for long periods of time and protects it from chlorine disinfection. According to the CDC, Crypto lives in the intestine of infected humans or animals which can shed the parasite through stool. Millions of Crypto parasites can be released in a bowel movement from an infected human or animal. You can become infected after accidentally swallowing the parasite. Crypto may be found in soil, food, water, or surfaces that have been contaminated with the feces from infected humans or animals.

These waterborne illnesses can be particularly active during warm wet weather cycles or in runoff, typically peaking during warm rainstorms. We always recommend that boaters carry filtration equipment and there are a ton of options on the market, but our new favorite is the Life Straw Equipped eddy+ bottle.

How does a Lifestraw filter work?

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A LifeStraw is a portable water filter designed for individual use. It is a long, narrow tube with a filter at one end and a mouthpiece at the other. To use a LifeStraw, simply insert the filter end into a water source, such as a river or water bottle, and suck the water through the straw.

The LifeStraw filter is made up of several different types of materials that work together to remove contaminants from the water. The first layer of the filter is a hollow fiber membrane, which is a thin, porous material that allows water to pass through while trapping contaminants on the inside. The second layer of the filter is made of activated carbon, which helps to remove chemicals and improve the taste of the water. The final layer is a mesh screen that helps to remove any remaining dirt or sediment.

As water passes through the LifeStraw filter, the hollow fiber membrane and activated carbon work together to remove a wide range of contaminants, including bacteria, viruses, and protozoa. The mesh screen helps to remove any remaining dirt or sediment, resulting in clean, safe drinking water.

One of the benefits of the LifeStraw is its compact size and portability. It is lightweight and easy to carry, making it an ideal choice for hikers, travelers, and anyone who may need to purify water on the go. It is also an excellent tool for emergency situations, such as natural disasters, where access to clean drinking water may be limited.