8 techniques for purifying water

When you go hiking, camping or face an emergency situation, it's crucial to know how to purify water to avoid illness. Untreated water can contain bacteria, viruses, parasites or harmful chemicals. Here are 8 effective methods to purify water, to make it drinkable wherever you are.
 

Summary:

• Boiling
• Filtration
• Purification tablets
• UV (Ultraviolet) system
• Distillation
• Gravity filtration system
• DIY filter with sand and gravel
• Chlorination
• Conclusion

 

 

Boiling is one of the simplest and most effective methods to purify water. By heating water to its boiling point for at least 1 to 3 minutes, you kill most pathogenic micro-organisms, such as bacteria, viruses and parasites. This technique is particularly reliable because it eliminates almost all biological threats. For altitudes above 2000 meters, where water boils at a lower temperature, it's recommended to extend the boiling time to about 5 minutes.

Advantages of purification by boiling:

• Requires only heat (fire, stove, etc.)
• Very effective against dangerous microbes

Disadvantages of purification by boiling:

• Does not filter sediments or chemical contaminants
• Requires an energy source to heat the water
• May change the taste of water

 

 

 

Filtration is a fast and practical method to purify water, especially during outdoor activities like hiking or camping. It involves using a specialized filter (like a straw or water bottle) to eliminate physical impurities, sediments and biological contaminants (like bacteria and parasites). Portable or domestic filters use a porous membrane or activated carbon to block particles and pathogens. Some advanced filters can also eliminate chemicals and heavy metals.

Advantages of purification by filtration:

• Effectively removes sediments, debris and pathogens
• Easy to use, portable and fast
• Improves water taste

Disadvantages of purification by filtration :

• Ineffective against viruses, unless using specific filters
• Requires regular maintenance (cleaning, cartridge replacement)
• Does not treat chemical contaminants without specialized filters

 

 Source: Lifestraw.com

 

Water purification tablets, usually based on chlorine, chlorine dioxide or iodine, are a simple and compact method for disinfecting water. They are particularly useful when traveling or hiking. When dissolved in water, these tablets destroy pathogens such as bacteria, viruses and parasites. You just need to wait about 30 minutes to 2 hours for the water to be drinkable, depending on temperature and water quality.

Advantages of purification tablets:

• Easy to transport and use
• Effective against most pathogens (bacteria, viruses, parasites)
• Ideal solution in emergency situations

Disadvantages of purification tablets :

• Sometimes leaves a chemical taste in water
• Less effective against certain chemical contaminants or heavy metals
• Requires waiting time before drinking

 

 

Ultraviolet (UV) water purification systems use lamps emitting UV rays to destroy the DNA of micro-organisms such as bacteria, viruses and protozoa, making water drinkable. This type of technology is fast and effective for purifying water without adding chemicals or altering taste. Brands specializing in outdoor equipment, like Katadyn, offer this type of product. 

Advantages of UV water purification:

• Effectively eliminates bacteria, viruses and parasites
• Fast (usually in less than 90 seconds)
• Does not change the taste of water

Disadvantages of UV water purification :

• Requires a power source (battery or cell)
• Not effective against chemical contaminants or heavy metals
• Water must be clear for UV light to work properly

 

 

Distillation is a purification method that involves heating water to boiling point, then collecting the vapor that condenses into pure water, leaving behind impurities and contaminants. This technique effectively eliminates bacteria, viruses, parasites, salts, heavy metals and even chemicals.

Advantages of filtering water by distillation:

• Removes almost all impurities, including heavy metals and chemicals
• Suitable for environments with heavily contaminated water

Disadvantages of filtering water by distillation:

• Slow and energy-intensive process
• Requires specific equipment
• May alter water taste

 

 

The gravity filtration system is a simple and effective method for purifying water, particularly when camping or in areas without access to drinking water. This system uses gravity to force water through a filter, thus eliminating impurities such as sediments, bacteria, and sometimes even chemicals.

Advantages of gravity filtration:

• Does not require electricity or batteries
• Easy to use and autonomous
• Effective for purifying large quantities of water

Disadvantages of gravity filtration:

• Slower than other methods
• Doesn't always filter viruses or chemicals thoroughly

 

 

 

A homemade filter using sand, gravel and sometimes charcoal is an ingenious solution for purifying water, particularly in survival situations. This filter works by passing water through different layers of materials that retain solid impurities and certain particles.

Advantages of sand filter:

• Easy to manufacture with natural and available materials
• Effectively filters debris, dirt and certain bacteria
• Does not require sophisticated equipment

Disadvantages of sand filter :

• Does not eliminate viruses or chemical contaminants
• Requires regular maintenance and cleaning of filtration layers

 

 

The use of small amounts of chlorine is common for purifying water in many regions. Chlorine drops (or unscented bleach) can disinfect water in 30 minutes, provided recommended doses are respected. This method is effective against bacteria and certain viruses.

Advantages of water chlorination :

• Easy to make with accessible products
• Very effective at killing pathogens
• Used in many large-scale drinking water systems

Disadvantages of water chlorination :

• Leaves a chlorine taste or odor
• Ineffective against certain chemical contaminants or heavy metals
• Requires precise dosage to be safe and effective

 

 

When you go camping, bivouacking or traveling, the choice of water purification method depends on several factors: ease of use, effectiveness against pathogens, portability and available resources.

For outdoor activities like camping or hiking, filtration is often the best option. Portable filters are practical, fast, and effective at removing sediments, bacteria and parasites. They also improve the taste of water, which can be an appreciated advantage. However, to protect against viruses, it's important to use specific filters or supplement with another method, like purification tablets.

Purification tablets are an excellent backup solution due to their lightness and ease of use. They are particularly suitable for travel or emergency situations, but may alter the taste of water and require waiting time before consuming the water.

For fast purification without altering taste, UV systems are ideal, provided you have access to an energy source. They are very effective against micro-organisms, but don't work well with turbid water or water containing sediments.

For situations where water is heavily contaminated or if you want an autonomous method without electricity, the gravity filtration system is practical and effective for purifying large quantities of water, but can be slower.

Finally, the best solution for filtering water while camping relies on combining several techniques. To maximize effectiveness, a three-step approach is recommended:

• Mechanical pre-filtering: Use cloth to remove visible debris.
• Portable filtration: Opt for a gravity filter based on hollow fibers or ceramic to eliminate bacteria and protozoa.
• Chemical or UV purification: To guarantee total filtration, finish with purification tablets or a UV lamp to eliminate remaining viruses and micro-organisms.

With this versatile method, you'll be prepared for any eventuality, regardless of the water source. Choosing lightweight, durable and effective tools guarantees you safe hydration and peaceful camping, while respecting the nature around you.