Types of Water Filters for Backpacking

Types of Water Filters for Backpacking

09/07/2021 Off By chadmin

Fortunately for us hikers, outdoor gear companies continue to innovate in the water filtration space. The result is a confusing abundance of options for every budget and style.

Here are a few of the most popular water filtration methods for hiking. This is subjective, but I’ve ranked them roughly in order of how well suited they are for hiking and backpacking, from most to least.




Gravity Filter

Maybe I’m lazy, but I love gravity filters. Simply fill a reservoir, hang it from a tree or place it uphill, and let gravity push the water through the filter and into the clean bag while you eat your snack or set up camp.

They’re easy and quite convenient for filtering large amounts of water for filling hydration bladders and for using around camp. They are also getting smaller and lighter by the year, making them excellent choices for lightweight backpackers.

Most filter elements need to be periodically backflushed or cleaned, will eventually need to be replaced, and can be damaged by hard impacts or freezing temperatures. Handle carefully and cuddle up with them in your sleeping bag on cold nights.







Squeeze and Inline Filters

These use similar filter elements to gravity filters, but with a different setup.

Squeeze filters are sort of like gravity filters but meant to work faster if you squeeze the dirty reservoir to push the water through the filter. In practice, they also work as gravity filters or inline filters when set up accordingly.

An inline filter is meant to be attached “inline” with your hydration bladder hose, allowing you to fill the bladder with dirty water. As you drink, the water is pulled through the filter and into your mouth. This is probably the fastest option for filling up and hitting the trail quickly. But it’s less convenient when you need a larger quantity of filtered water around camp (say, for cooking food when you don’t plan to fully boil the water).

Inline and squeeze filter elements, being very similar to gravity filter elements, have the same issues: limited (but long) lifespan, periodic backflushing, damage from dropping or freezing.

Pump Filter

My very first backcountry water filter was a pump filter. They are excellent for getting water from shallow sources where a reservoir is hard to fill and can be efficient with large quantities of water. They also will keep your upper body in shape along with your legs on a long backpacking trip!

While some very good pump filters exist, I personally prefer the hands-off convenience of a gravity filter. Pumps also tend to be bigger and heavier, making them less suitable for lightweight backpacking.



Chemical Treatment

Chlorine dioxide is the only chemical treatment approved for Crypto, and it takes four hours of treatment time, which is challenging for most hikers to arrange. No one wants to carry around a bunch of extra water that they can’t drink for hours.

Therefore, while chlorine dioxide is appealingly lightweight, it’s a risk to use it in areas with higher human or animal activity upstream. A few tablets can make a good emergency backup to a filter system though.

Chlorine or iodine don’t work at all against Crypto and tend to have a more objectionable taste, making them even less appealing.


UV Purifier

UV purifiers are technically not filters (they protect against viruses too), but I’m including it for completeness. It’s a small, battery-powered device that purifies a bottle’s worth of water by inserting it, pressing a button, and waiting for a bit.

They are fast and easy, but awkward for cleaning large amounts of water in multi-liter hydration packs. They also have the potential to fail or run out of battery. Most importantly for backcountry applications, they’re not effective in cloudy water; they neither remove the gross particulate matter nor kill pathogens effectively.

Bottle Filter

Despite the large number available on Amazon, I don’t see many serious backpackers using filter bottles. Though convenient for a single bottle’s worth of water, they’re unsuitable for filling a larger hydration bladder for long miles or hot weather. The only case I can see them working well for is a day hike in an area with frequent water sources.




Straw Filter

Like bottle filters, I’m not quite sure what the best use case is for straw filters in the backcountry. They only allow you to drink when actually at a water source, instead of filling a reservoir to take with you; I know basically no one who manages water this way while hiking.

They also seem redundant. A cartridge from a gravity or squeeze filter could be used as a straw filter if needed while being far more versatile. They might make a reasonable backup, but chlorine dioxide tabs are far cheaper and smaller.