Backpacking Water Purification

We all know that you can’t safely drink water out of a river.  Sure, you might know someone who swears that they don’t need to filter their water, but let’s face it- that “one guy” is always at least a little bit crazy.  Water purification when hiking is absolutely a critical need on the trail.  It doesn’t matter if you’re taking a couple mile day hike, or if you’re planning a multiple day hike- you need to always bring at least one method of water purification.  Let’s talk about backpacking water purification, and specifically what I carry in my backpack.

Iodine Tablets

Iodine tablets are possibly the least enjoyable backpacking water purification method.  Iodine tablets are messy (they stain your clothes and hands), slow (they typically take 15 minutes to take effect), and they leave a funny taste in the water.  In addition, iodine tablets do absolutely nothing to improve the quality of the water itself.  If you place iodine tablets into muddy water, that water will still have silt in it by the time the tablets are done.  With all that being said, I still use iodine tablets today.  I like the low cost of the tablets, the ease of use (just fill your water bottle, and toss a couple in), and the light weight of the tablets.  If I’m planning a day-long hike across more than five miles, iodine tablets are always in my pocket.  To me, there’s nothing faster and easier than filling up my water bottle in a stream, and tossing a couple tablets in.  Then again, I’m not too particular about how my water tastes- I just want to fill up my bottle and keep moving.

Pump Water Filters

The most popular method of water purification is the pump water filter.  These work by passing water through a filter (nicer models have a couple of filters), which is all powered by a hand pump.  I personally prefer Katadyn filters, such as the “Hiker” model that Katadyn sells.  These filters are extremely effective at removing water pathogens, and they leave no aftertaste in the water.  Pump water filters are also great for improving the quality of the water, removing silt and dirt from the water.   Once you add in ease of cleaning (I run mine through the dishwasher at home), these filters are hard to beat.  The only downsides is the cost (look to spend upwards of $100 for a nice model), and the hassle of hand pumping your drinking water.  If you’ve got multiple water bottles than need filled, it can take a few minutes to fill them all up.  That being said, the Hiker model that Katadyn sells now can pump up to two liters of water per minute, so the hassle of hand pumping drinkable water is definitely not as bad as it used to be.

Infrared Filters

A relatively new way of filtering water is to use specialized infrared lights.  These devices work by killing harmful bacteria and viruses by shining a high intensity light into the water.  This high intensity light quickly and effectively kills over 99% of harmful viruses, bacteria, and protozoa.  This is an important distinction, because some hand pump water filters don’t even claim to filter out viruses.  The downside of these devices is the cost (around $150), but prices on some models are starting to drop.  Personally, I’ve never used this method.  The high cost, and reliance on batteries makes me uneasy about relying on this method for water purification.


Regardless of which backpacking water purification method you use, always carry a spare.  Pump water filters break, batteries wear out, and iodine bottles can get lost.  When you’re miles away from civilization, you need safe drinking water.  Out here in Montana, the biggest threat from unfiltered water is Giardia.  If you drink water that is contaminated with Giardia, you may experience vomiting, diarrhea,  and stomach cramps.  None of these things are anything that you want to have, when you are miles away from home.