No matter where you are backpacking, you are going to want to treat your drinking water. Giardia is prevalent, even in fresh mountain snowmelt and you don’t want to have to cut your trip short if you contract some sort of gut wrenching bacteria. protozoa or virus. The unpleasant consequences of drinking untreated water include nausea, vomiting, diarrhea, fatigue, and loss of appetite. You cannot tell whether water is safe by looking at, smelling, or tasting it. Lightweight water treatment for backpacking these days includes filters, UV light, chlorine dioxide tablets/drops, squeeze style filters, straws, and water bottle filters.
Water filters are a popular choice among backpackers, especially those hiking in a group of 2 or more. The way the filter works is that it catches bacteria and protozoa inside the filter so that you don’t ingest them. The microscopic openings in the filter are called microns which is 1/1000 of a millimeter. Water filters with a micron size of one or smaller will remove parasitic eggs, larvae, and protozoa while water filters with a micron size of 0.4 or smaller will filter out bacteria.
There are two main types of water filters, pump style and gravity fed. For the pump style filter you place a tube from the filter into the dirty water and then you manually pump the water into a bottle or container. The gravity fed style takes a little longer but requires less effort as you simply hang the dirty water bag which will then run down through a tube and filter into a clean water bag.
Platypus Gravityworks 4L Filter System – This is a gravity fed filter system that also comes in a 2 Liter version. It has a very fast flow rate and can filter 4 Liters of water in 2.5 minutes! It has a hollow fiber filter and removes bacteria and protozoa down to 0.2 microns. Weight: 11.5 oz, Dimensions: Filter – 2 x 8.5 inches, Resevoir – 17.7 x 9.1 inches
Katadyn Hiker Pro – This is a manual pump style filter. Approximately 48 pumps per minute yields 1 Liter of water. It is a glass fiber/carbon core filter and removes bacteria and protozoa down to 0.2 microns. Weight: 11 oz, Dimensions: 6.5 x 3 x 2.4 inches
The Sawyer Squeeze is the method I use for all my backpacking trips. It is really simple, effective, and quick. It is a hollow fiber filter and removes bacteria and protozoa down to 0.1 microns. the Sawyer fills most water bottles in around 30 seconds. It comes with Mylar foil bags (BPA Free) which you put your dirty water in, you then attach the filter to the Mylar bag, last you squeeze the water out of Mylar bag and into your clean water bottle. You can also drink directly from the filter because it has a pop up drinking spout. It comes with a syringe for easy cleaning/back-flushing. The Sawyer Squeeze is very affordable and also comes in a mini version. Weight: (Regular) 3 oz (Mini) 2 oz, Dimensions: (Regular) 5 x 2 inches (Mini) 5 x 1
Chlorine Dioxide Tablets and Drops
If you want to go extremely ultralight for your water treatment method consider using a chlorine dioxide formula such as Aquamira. Chlorine dioxide is a strong germicidal agent which has been used by municipal water treatment plants for decades. It does not contain iodine, chlorine, or affect the color or taste of your water. To use Aquamira, you mix solution A with solution B and wait 5 minutes before adding it to your water. Then you wait another 15-30 minutes for the solution to continue to react and kill off bacteria and viruses.
Another type of chlorine dioxide water treatment are the Katadyn Micropur Purification Tablets. These tablets are individually wrapped and kill viruses and bacteria. You simply drop one in your water and wait for the recommended amount of time.
The downside to using chlorine dioxide for water treatment is that some studies claim it does not kill Cryptosporidia, which is a microscopic parasite. Katadyn claims that their Micropur Tablets do kill Cryptosporidia but take at least 4 hours. You could use this method overnight to treat your water and probably be okay.
These are battery operated handheld devices that use Ultraviolet light to kill bacteria, viruses, and protozoa. This method is chemical free and doesn’t alter the taste or pH of your water. Its fairly fast and lightweight. The most common brand among backpackers is the Steripen. I have tried this method and had some trouble getting my Steripen to function properly in cold water. I ended up having to use my emergency water purification tablets. I got so frustrated with my Steripen that when I got home from my trip I sold it. This was years ago though so perhaps the newer versions have improved. Weight: 3.8 oz, Dimensions: 6.1, 1.5, 1 inches
The Lifestraw was originally created for natural disaster relief efforts and is used by millions of people around the world. It is very affordable and lightweight. It removes bacteria and protozoa down to 0.2 microns and can filter up to 1000 Liters of water. It is basically a filter in a tube with caps on either end which you remove when you want to drink and then use it like a straw. After drinking you blow through the straw to clean the filter. Weight: 2 oz, Dimensions: 9 x 1 inches
The Frontier Straw Filter by Aquamira is another option. This straw filter does a good job removing parasite cysts like Giardia and Cryptospiridia but does not filter out bacteria and viruses. The manufacturer suggests use combined with a chemical treatment. It is a carbon based filter so will produce some dust when you first use it and it is only good for filtering 30 gallons of water. Weight : 1 oz
I highly recommend the Grayl for a water bottle filter. This is a press filter that has a patented magnet that removes pathogens and inorganic compounds, an activated carbon filter, and an antimicrobial element. It filters viruses, bacteria, protozoa down to the 0.1 microns. The Grayl also filters out chemicals and heavy metals. It is really easy to use and only takes about 15 seconds to press. Weight: 10.9 oz, Dimensions: 9.625 x 2.875 inches
Which Method is Right for You?
Weight, speed, reliability, effectiveness, and ease of use are all things to consider when deciding on the right water treatment method for you. If keeping the weight down is most important to you, then choose Aquamira drops. If you want a totally reliable method, then choose a system without bulbs or batteries like the Katadyn Hiker Pro filter. If you are looking for something super simple to use go with with Sawyer Squeeze or the Grayl waterbottle. If you are hiking alone and water is plentiful, try the Lifestraw. For larger hiking groups choose something like the Platypus Gravityworks filter.
Please a comment below and share your thoughts on these methods of water purification for backpacking. I would love to hear what method you use while out in the backcountry.