This post is part of the Backpacking Gear for Beginners course.
Why do you need a water filter?
No matter where you are, there’s a chance the water source can have protozoa like Cryptosporidium or Giardia. Both cause stomach problems like diarrhea. Not something you want on your hiking trip.
To make it safe to drink we can either boil the water, or use a water filter, UV pen or purification chemicals. All methods make the water safe to drink.
Boiling the water is time-consuming and requires a lot of fuel for your stove. In an emergency it still works. It will be safe to drink after you bring the water to a rolling boil for 1 minute.
Another method is a pump filter. With the handle, you pump water through a very fine filter which catches protozoa like Cryptosporidium or Giardia. Pumps require a bit of work but is quick to get multiple liters of water. You can use gravity to do the work for you as well, letting the water drip from one water bladder through a filter down to another bladder.
A third method is to use chemical drops or tablets in the water. Over 15 or 20 minutes, the chemicals do their work killing things in the water. Sometimes the water has a taste after.
The last method is to use a UV light like a Steripen which sterilizes any bugs in the water, rendering them harmless to you and your stomach.
Having a way to get drinkable water is one of the 10 Essentials. Even for day hikes, bring a way to get more water.
Measure how much you need per day
We need to estimate how much water you need per day. These are estimates that I roughly use. They center around using about .5 liters per hour hiking and adding meals before and after. If the weather is warmer, then I’ll need more.
- Breakfast and getting ready: 1.5 liters
- Morning hiking and lunch: 1.5 liters
- Afternoon hiking: 1.5 liters
- Dinner and evening: 2 liters
These numbers will be different for you. It depends on age, temperature, duration and intensity of hiking and what kind of drinks you’re having.
Now that you know what water you’ll need and when you can think about when you want to get the water.
- Breakfast and getting ready: filtered the night before
- Morning hiking and lunch: filtered before starting to hike
- Afternoon hiking: filtered around lunch
- Dinner and evening: filtered in camp before dinner
Exactly when you filter or clean water depends on your water sources. These are when I like to get the water ready.
Gravity filters are the easiest but large
For filtering large amounts of water, gravity filters are very convenient. They use 2 water bladders and a filter in between which can be large for a solo lightweight setup. For large groups, they work very well. Fill the dirty bag with water and hang in a tree. Once it’s done, there’s 3-4 liters of clean water.
Test different methods. This might not work well for you.
Lifestraw are great for emergencies but…
Lifestraws have become popular in the last few years for their simplicity. Just drink from any water source and you’re done. The problem comes in when you need to store some water to take with you. There’s no way to just fill a water bottle with clean water to have for hiking and cooking. Not all trails have water at regular intervals.
