Get resupply point updates, planning tips, and more


On a long-distance hiking trip, practical water treatment options come in two varieties: filtration, and chemical treatment. Some hikers even choose not to treat their water at all, though they are in the great minority. The topic of treating water can be as simple or as complicated as you make it. If you are interested in the science of water treatment you can check out the links in the ‘More Information’ section at the bottom of this page. Otherwise we’ll keep it simple.

Filters vs Chemicals

There are two kinds of contaminants that can make water unsafe to drink: chemical contaminants and biological contaminants. Chemical contaminants include gasoline, chemical herbicides, oil, etc. Biological contaminants include E. Coli, giardia, cryptosporidium, etc.

A good filter will filter out both chemical and biological contaminants. Filters don’t alter the taste of the water like some chemical treatment options do. However, filters are slow, laborsome, and you must replace the filters on time for them to continue being effective.

Good chemical treatments (like Aqua Mira) will neutralize biological contaminants, but not chemical contaminants. They are generally easier to use: you just add the chemical to the water, toss the bottle in your pack, and continue hiking down the trail as your water treats. Chemical treatments are also lighter in weight.

Since chemical contaminants are uncommon along most of the PCT (Southern California has some exceptions) most PCT thru-hikers use some kind of chemical water treatment.

Lightest Treatment Option

Chemical treatments are always lighter than filter options. Chlorine-based crystals or tablets are the lightest. One example is Potable Aqua. Chemical treatments that come in a liquid state, like Aqua Mira, are only slightly heavier.

Water Containers

You can carry your water in water bags/bladders, water bottles, or canteens. Water bags and bottles are the most common. Most water bladders have sipping tube attachments available, and many hikers find them convenient. Bladders take up very little space when empty. That’s a nice feature – especially for the dessert where you’ll need a couple of two liter containers to carry enough water. Plastic soda bottles are also nice because they can be replaced cheaply and often. That means you never have to deal with water mold building up inside them. Heavy plastic water bottles (such as Nalgene bottles) are unnecessarily heavy for long distance hikers.

  • Platypus Platy Water Bottle – 70 fl. oz.

    Platypus Platy Water Bottle – 70 fl. oz.

    1.3 oz

  • Platypus Big Zip LP Reservoir – 1.5 liters

    Platypus Big Zip LP Reservoir – 1.5 liters

    5.4 oz

  • Platypus Big Zip LP Reservoir

    Platypus Big Zip LP Reservoir

    6 oz

  • EVERNEW Water Container

    EVERNEW Water Container

    1.5 oz

Lightest Carrying Option

A 2.4L Platypus Bag weighs just 1.2 oz (that’s 60% less than an empty 2L soda bottle). A 1L bag weighs even less. To learn more about Platypus Bags, click here.

More Information

If you want to delve a little deeper into the subject of water purification, here are some places you mght start:

  • For a discussion about various kinds of water treatment options click here.
  • For a very exhaustive water treatment article by click here.
  • For a backcountry water quality article by REI click here.


Has the information above changed? Know something other hikers should know? Leave a comment below.