Winter Water Bottle Insulation and Hydration: A Simple Approach

Winter Water Bottle Insulation and Hydration

There’s an art to winter water hydration and creating an insulation system that keeps your water from freezing, but still maintains it at a drinkable temperature. Like any art form, there are many different systems and gear combinations that you could use to stay hydrated in winter. Here’s an approach to winter water bottle insulation and hydration that works for me and that works with just about any type of wide-mouth bottle, insulation sleeve, and backpack.

Flavor your hot water to make it taste better
Boil and then flavor your hot water to make it more appealing to drink.

Winter Hydration Basics

  1. You usually have to carry all of the water you need for the day on your person in winter because most water sources are frozen over or buried in snow.
  2. Most people carry 2 or 3 liters for an all-day hike and augment it by pre-hydrating with 2 liters of liquid intake at breakfast and on the way to the trailhead before the hike starts.
  3. It’s best to fill your bottles with boiling water. I find an electric kettle works the fastest to heat water.
  4. While you perspire and exhale considerable moisture in winter, much of it is hard to notice, and you won’t feel thirsty. Nevertheless, you must force yourself to drink and pee. This is best done by observing the color of your urine and keeping track of your rate of water consumption. I like to drink about a liter every two hours. You can delay when you start, by prehydrating before your hike. Dehydration accelerates hypothermia, which you want to avoid, in part because it makes you stupid. Bad decision-making and winter hiking don’t mix well.
  5. Hydration systems with drink hoses have a tendency to freeze on long day hikes. Hydration systems also limit your ability to measure how much water you’ve ingested since you can’t see the reservoir level and don’t know when it will run dry.
  6. Wide-mouth water bottles are much less prone to freezing than ones with narrow necks. You can also prevent water bottle caps from freezing shut by turning your bottles upside down.
  7. Weight is always a consideration on winter hikes. Water is heavy, so it helps to minimize the weight of the containers and insulation used to carry it.
  8. You can’t drink water if it’s too hot to consume and drinking cold water will chill you. That’s why people just don’t eat snow. I’d advise against using insulated metal bottles for the same reason, unless you want to carry a small thermos of soup, like tomato soup, which can really perk you back up on a frigid day.
Insulated Water Bottle Holders
Insulated Water Bottle Holders

Short Term and Long Term Storage

The basic idea is to divide your water into short-term storage and long-term storage. For your short-term storage,  keep a single insulated bottle of water in a side pack pocket or attached with a carabiner to your hipbelt: it should stay warm for 2-3 hours.

Good insulated water bottle covers from Forty Below and Mountainsmith are unobtainable this year or in very short supply. But a lower quality insulated carrier like the 32 oz insulated carriers from Nalgene can keep your water from freezing that long. Make sure you buy a sleeve with an insulated cap.

Keep the rest of your water inside your backpack in an old wool sock or another insulated sleeve, nestled together with the extra insulated clothing you keep in your pack. When you empty the short-term bottle, replace it with one of the full bottles inside your backpack, using the now empty external sleeve. Your insulated clothing, like a parka or mid-weight synthetic/down jacket, should keep your water quite warm until then. (Hint: put a cheese sandwich next to these bottles and you’ll have a hot melted sandwich for lunch). If you’re worried about the bottles leaking, just wrap them in a plastic bag.

One of the advantages of this approach is that you only have to buy one insulated water bottle sleeve, instead of several. Your long-term water will also stay a lot hotter inside your pack than if you carried it all externally.

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  1. Hi Philip,
    I enjoy your site. On the topic of needed fluid intake, I read a wide variaties of opinions. Adventure Alan’s article, found here furmulates the counter argument quite thorough:

    As you stated, drinking in below freezing conditions may be hard.

    • Actually, Alan and I are in violent agreement. The entire sugared water additive market is a farce and you should figure out what your preferred hydration requirements are. I only suggest mine to be helpful, not to mandate them. However, Alan does not touch on winter hydration which is a very different animal than what he presents in his article which is decidedly geared to three-season (summerish) conditions. Your body does not perceive thirst in winter the same way – in fact not at all – so you must force yourself to drink. I like to keep track on a loose schedule since that works for me. I also like to flavor a few of my bottles with tea to make them more palatable to drink since they are hot or warm.

    • Koen, this is a great article, thank you for sharing. I have long been of the opinion that people tend to overhydrate and my hiking buddies always seem concerned that I don’t drink much when hiking, but the honest truth is that I do not need to drink much. If I drink a liter over two hours or prehydrate before a hike (like Philip mentions he does) I will just have to pee every 20 minutes, and that is just way too much peeing (and seems like a waste of water!). So I think the maxim of “drink when you are thirsty” is a good one, though when exercising I tend to make myself drink before I think I will get thirsty (especially in the winter or a desert). I have never had an issue with dehydration but I do often get lightheaded or a headache when I drink too much liquid and don’t eat enough (I never do this on the trail, just at home when I’m too lazy to cook food).

      I guess what I’m trying to say is, if you know you need to drink a lot to stay hydrated, then you should do so! But if you drink a lot and then pee a LOT like I do, maybe you don’t need to drink nearly as much as you think you do. Seems like some folks have a lot of anxiety around becoming dehydrated, and unless you are far away from a water source, this anxiety is unfounded. Of course, anxiety is often illogical so you do you, drink and carry as much water as you feel you need. :-)

      The article helped articulate my hydration thoughts, of which I have a lot, so thank you again for sharing, Koen!

  2. I lerned a lot reading your website some years ago, but I wasn’t able to find the insulated cover you reccomended, so I used the Salewa Insulation Cover. It’s not for extreme cold, is cheap and simple, but very well made and very effective even during a day hike at -20 °C with a lot of wind on Dolomites. In the late afternoon my weather-sealed Pentax K2-II died (and was inside my insulated jacket!), instead the water was cold but not freezing just in this cover in the mesh pocket of my pack (big surprise!).
    I used it also in the Arizona desert in august, the water stayed well protected and cold for few hours under the hot sun. This cover was with me during summer on every desert trail in the Usa and replaced the horrible and heavy insulated bottles. After years of use and washing, it’s like new. I don’t know if it’s available in the Usa, but it’s worth a try.

    • Not a long on words, are they? No product description.
      I found a great water bottle insulator with a zippered cap and webbing you can use to attach it to your hip belt or pack. Literally writing a review for early next week. It’s a real find.

      • Words probably are not their best skill… in the italian website they use words that don’t exist! Probably the original text is in german and a translator made a lot of mistakes.
        But the cover is nice! It’s like a glove for the 1L Nalgene, if you need I can send you a photo.
        I’d like to buy another one for this winter but is difficult to find these days, so in the next snow hike probably I will try an insulated cover for babyfood: cheap but light and effective for winter in the city. It was for my son’s meals and was also perfect with several pieces of hiking gear I used for him (I missed a lot the outdoors during pregnancy and after, so I used my camping gear for babyfood and it was a great idea). I hope it works with my Nalgene too!

  3. What do you think of the Outdoor Research water bottle parkas?

  4. If you’re really hard up for finding insulating covers, consider making one out of old CCF foam pad pieces. Before my lovely daughters got me some OR bottle covers, I snowshoed & xc skied a lot of winter miles using bottle covers made from cut up pads, held together with Duct tape. Certainly not elegant but they served their purpose.

  5. Anyone else get frustrated with 1L HDPE Nalgene bottles ballooning when you fill them with boiling water? The bottom rounds out and they don’t stand up. Do the Hunersdorf Bottles have the same problem?

    • I get a little rounding at the base but it’s not a big deal. If it botters you just re-melt them. Hunnersdorf bottles (which are unobtanium this year) do the same thing. What I do appreciate about the HDPE is that the threads expand into the cap and form a tight seal.

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