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It’s happened to all of us: You’re hiking on a crisp winter day, enjoying the scenery and fresh air. You reach for your water bottle to take a swig, but nothing comes out. When you look, you see a plug of solid ice covering the bottle’s mouth.
Hydration is as important in winter as it is in summer, but fail to plan ahead, and you could find that your only source of water is frozen and unavailable to you. It’s an annoying problem, and in the worst cases, it could even force you to abandon your hike. But this isn’t something you have to suffer through every winter: With a little bit of planning, you can keep your water supply liquid and easy to drink in the coldest temperatures. As for how to do it, you have a few options.
Use an Insulated Bottle or Bottle Jacket
The easiest way to avoid having your water freeze is simply to insulate it. Bring a thermal bottle, and you can keep your water liquid for hours, or even days, in sub-freezing temperatures, depending on how high quality it is. For the harshest, coldest days, we like the Yeti Rambler 32 ounce Bottle, which we’ve used to keep hot drinks hot on ice climbing trips and long ski tours in Colorado’s Rocky Mountain National Park. The downside: insulated bottles are generally bulkier and heavier than non-insulated ones, which can add a few more ounces to your pack
Don’t want to buy a new water bottle? A bottle jacket can help prevent standard water bottles from freezing, though they don’t usually work as efficiently as an insulated bottle. Liberty Mountain’s Insulated Bottle Carrier features foam insulation and is sized to fit a standard 32-ounce Nalgene.
Pack Hot Water
It’s simple physics: Hot water has to cool off before it can freeze. Pour hot water into your vessel in the morning, and instead of being frozen hours later, it will just be cool enough to drink. This trick is good for dayhikes, and can work on multi-day trips, as long as you’re willing to bring extra fuel. Be sure to use a bottle that can stand up to boiling water, or you might end up enjoying a hint of melted plastic with your drink in the best case scenario and burning a hole straight through your o bottle in the worst. To help it keep warm for longer, store the bottle wrapped in your extra layers inside your pack’s main compartment, rather than the bottle sleeve.
Buy an Insulated Bladder
Hydration bladders aren’t immune to freezing during the winter. The water in their hoses often solidifies first, plugging them up and making them impossible to drink from. If you plan to regularly use your bladder in the winter, it’s worth investing in an insulated one, like the Hydrapak Hydrasleeve. Tip: Blow air into your hose after every sip to force the water in the hose back into the reservoir where it’s less likely to turn into ice.
Use a Soft Flask
One simple way to keep your water liquid and easy to access: Fill a soft flask and keep it between your mid-layer and base layer, so your body heat keeps it warm as you move. All you have to do to hydrate is reach inside your jacket and pull it out. You can only fit a liter or two inside your jacket before starting to feel like a Teletubby, however so this strategy is best used it on short day hikes. Alternatively, keep an insulated bottle or bladder in your pack and top them off at breaks.
Sleep With Your Water
On overnight hikes, slip your water bottle into your sleeping bag to keep it from freezing overnight when the mercury drops. (Just make sure the cap is on securely.) Even better: Make your bottle pull double duty by filling it with boiling water and cuddling with it to stay cozy overnight. In the morning, you can drink the now-cooled (and still liquid) water.
Keep Your Water Close to Your Body
This one’s an underrated trick that I picked up competing in ski mountaineering races: Instead of bringing a hard-sided bottle, use a soft flask and keep it inside your clothing, between your mid-layer and base layer, so your body heat keeps it warm as you move. (The HydraPak UltraFlask 500 is a good pick.) Not only does this ensure that your water stays liquid, it also keeps it close at hand, so all you have to do to hydrate is reach inside your jacket and pull it out. You can only fit a liter or two inside your jacket before starting to feel like a Teletubby, so this strategy is best used on short dayhikes. Alternatively, keep an insulated bottle or bladder in your pack and top them off, or plan on melting snow during your breaks.