Scooping your mug into the lake and downing a mouthful of fresh lake water is awesome. Feeling confident that you can dunk your water bottle into your water source is a unique spot to be in. Unfortunately, I only do it here and there in the Boundary Waters. Everywhere else, it’s good to have options on how to pick the right outdoor water filter. Here are the methods I have tried with pros and cons for each.
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#1 Hand Pump Water Filter
Pro: This type of outdoor water filter has been a go-to for years. They are really versatile and are good in all kinds of situations. Hand pumps are also common to find in outdoor stores, and this is also handy because it is easier to find replacement filters.
Con: Oh man, can they gunk up. Even when pumping totally clear water, it seems like they need constant lubrication to keep smooth pumping.
Notes: Make sure you keep some lube handy, and it’s good to read the manual so you know how to service and backflow it.
#2 Gravity Water Filter (Katadyn or Platypus)
Pro: Set it and forget it. I love my gravity outdoor water filter, and it is my method of choice for the Boundary Waters. It also filters water super fast and usually holds quantities that are 3 liters or greater. Just tie the filter to a tree or branch and stretch the tube to your Nalgines or Dromedary.
Con: With increased filter volume, the filters go quicker. If you do not have an abundant water source, this can be challenging. Not easy to use if you are pulling from a trickling stream; lakes and ponds are best. Also, a gravity filter can be challenging to use in a canoe.
Notes: In camp is really where this shines. Having a quick and easy filtered water source is awesome.
#3 SteriPen Water Filter
Pro: These are super small, lightweight, and easy to use. They typically work pretty quickly too.
Con: Steri pens are usually battery-powered. If this is the only water cleaning method, you have to make sure you have a way to keep it charged. Also, make sure you start your trip with it charged is key. If they have lots of gunk, it can take longer to clean it confidently. I have a hard time trusting it with scummy-looking water.
#4 Tablet/Liquid Chemical Pure
Pro: Tablets for purifying liquids are very convenient; it is considered a set it and forget it method and is pretty common.
Con: Wait time can be a pain. Depending on the quantity of water you’re purifying, it could make you wait up to an hour. It is possible to run out, though some can refill and preconcentrate like Polar-Pure (No longer available). If misused, they can make you sick. These can have a taste that some find off-putting.
Note: Some folks can have allergies or can have gut problems with these. It’s good to try these at home before using the trail.
#5 Sawyer Squeeze Water Filter
Pro: These systems are super lightweight and often choose lightweight backpackers needing an outdoor water filter on longer trips.
Con: I find these to be a bit fussy to work with, and I also find that filtering a lot of water is a pain because it takes so much time (although this is a common problem with filtering)
#6 Katadyn BeFree Water Filter
Pro: Lightweight and packs down super small.
Con: To make it applicable to backcountry use, you have to have another container that you use as a container for unpurified water to pour into the “BeFree” bottle. Filters may burn through faster because they are a bit small in size.
#7 Boil Your Water
Pro: Tried and True!
Con: Takes time, fuel (or fire), and the setup to do it.
If you’re spending most of your time in the BWCA, I would say, hands down, go with the gravity filter. No matter what you buy, READ THE MANUAL. There are usually tips, maintenance, storage, and things that are helpful to know when using your filtration tool. When storing them, make sure they are dry! Is there something I forgot? Drop a comment below!