Few things are as refreshing as drinking all-natural water straight from a cold mountain stream, untainted by chemical treatments. Or to just plunge your face into a spring on a hot day and quench your thirst without fussing around with filters, pumps, and hoses.

If you are smart about choosing your water source, you could go for days, weeks, or even years without treating your water and never get sick. It's a gamble, but after spending a few days stepping over moose poop, or seeing a bloated dead animal floating in a water source, or worse yet, having to witness your friend doubled over with stomach pains and running off into the trees to decorate the forest in vomit or explosive diarrhea... Anyway, what I'm trying to say is, that stuff kind of diminishes the "all-natural" romanticism of drinking from a cold mountain stream, so I treat my water.

Everyone has their own preferred method, but here’s what I do.

My Water Treatment Method

My method for treating drinking water in the backcountry is a combination of household bleach (one drop per 16 oz.) and/or an inline or straw filter. And don't forget the often skipped step of cleaning your hands after touching potentially contaminated water. I carry a small bottle of hand sanitizer for this. Not doing so could negate everything you do to treat your water.

Why I use bleach

How I use bleach

My method is based on recommendations by the Centers for Disease Control, the American Red Cross, and hours of additional reading. If you find any mistakes or have questions or suggestions, please contact me at grayson.ryan@gmail.com. I will always be happy to learn something new and will update this information accordingly.

1. Fill an eyedropper with bleach.

Before heading out, I fill an eyedropper bottle with common household bleach. I use an old Visine bottle or breath drops bottle. Since bleach will degrade in direct UV light and become less effective, don't let it sit in the sun.

To fill the bottle without spilling bleach, when a funnel isn't available, use a ZipLoc bag as a funnel. Put the desired amount of bleach in the bag. Hold it by one of the top corners and cut a tiny bit off the corner that's above the bleach. Tip the bag and pour the thin stream of bleach into the dropper bottle.

I keep the bottle in a ZipLoc freezer bag to prevent damage to gear and clothes. So far, I have not had a problem.

2. Fill your water bottle with water.

The best water source is actually the top few inches of lake water. The longer time under the sun’s UV rays does a lot of the sterilization for you. Otherwise, a spring or swift moving creek will be fine. 

No matter what chemical treatment you use, if the water source is not clear, tie a bandanna or some other cloth around the top of the bottle when filling. If your water is still cloudy, let it sit until all sediment has settled, then pour the clear water into another bottle before treating. Chemical treatments are much less effective if the water is not clear or contains free-floating organic material. Organisms that are clinging to free-floating particles are harder to kill.

3. Add one drop of bleach per 16 oz. of clear water.

Use two drops if the water is really cold, cloudy, or discolored. If your bleach is not the common 4-6% solution of sodium hydrochlorite you may have to use more or less. The amount of sodium hypochlorite added to bleach may depend on the season. For example, more may be added in the summer to compensate for the higher temperatures. It could be as high as 10%, so check your bleach bottle’s label and adjust dosage accordingly.

4. Shake it like a Polaroid. 

5. Screw the cap nearly all the way on, then squeeze the bottle until it starts to pour out, and then tighten the lid. 

This ensures that the entire bottle, including the cap and threads, get disinfected.

6. Wait 30 minutes. And in the meantime, clean your hands with a hand sanitizer. Not cleaning your hands after touching a contaminated water source could negate everything you have done to prevent a water-borne illness.

If after 30 minutes, your water does not have a slight chlorine smell similar to municipal tap water, repeat steps 3 through 5. Think of bleach as an army of soldiers you're sending into battle. They kill organisms, but die in the process. The more organisms there are to kill, the more soldiers you need. That's why it may be necessary to treat a second time. And why sometimes you'll smell or taste more chlorine than other times. Keep in mind though, this isn't the fault of bleach alone. It's true for any chemical treatment.

One last thing, the decomposition rate of bleach increases by a factor of 3.5 for every 18° F increase in temperature, so if not stored at 60-80 degrees, it's probably a good idea to dump it out and replace it after a couple weeks to be safe.