Despite how we may feel while out exerting ourselves during the winter, staying properly hydrated is just as important as in the summer months. Believe it or not, dehydration is a common occurrence on the trail during colder days. Water treatment not only helps us combat this, but it also helps keep our packs lighter. What kind of weight savings are we talking about to help keep things light? To quickly break it down, 1 liter (or one Nalgene) of water weighs 2lbs 2oz. Add in a 6oz Nalgene bottle and you're brought to 2lbs 8oz. Double that and you are at 5 lbs just with water and two bottles. If you were to carry two more, you can see where this leads to and so on.
While many of our 3-season methods can have their drawbacks in the winter season, there are still ways to keep your water clean so that you can enjoy your backpacking or day hiking trip. Below I will go over some considerations with these different methods in regards to winter use. I'll also share a couple of tips and tricks I like to use for carrying my cleansed water during my winter backpacking adventures.
*Tip: Always boil or purify your snow melted water as there can still be viruses or bacteria lingering around.
Boiling Method
The age old way to clear our drinking water of any impurities. Boiling water is a great way to kill bacteria and is the one I find to be ideal for my winter trips.
One of the benefits that I love with winter travel is that water (snow) is pretty much around you at all times depending on your location. Simply melt snow, completely boil and you’re ready to go. Having constant access to this allows for carrying just a couple of liters in your bottles or water reservoir. This quick and easy method could also be used without a stove if you found yourself heading toward a bad situation. All you'd need would be your cooking pot and a small contained flame.
The drawback to the boiling method is the fact that snow has to be melted to create water. In order to melt snow you need fuel and more of it than your typical 3-season amount per trip. This is due to the fact that snow is mostly air. Even when in high alpine and collecting from glacial streams, more fuel is still needed. Wind and cold can also come into play depending on which stove you choose to use on your winter endeavors. This can cause your fuel consumption to increase 3 to 4 times more than 3-season use with the same stove. With this in mind, two good options would be to use an efficient integrated system or a stove that uses white gas. An efficient alcohol stove may also be a good option depending on factors such as location, trip duration, your trip goals, etc.
If you are above about 6,000ft in elevation, it is good practice to let your water boil for 3 mins or more. If you are below 6,000ft at least a minute should do. If you are running low on fuel or trying to conserve, you will still want to at least melt the snow and let it reach a boil. Following this, pour it into your bottle, add a tablet and let it do its job before consuming.
Pros: quick, effective, reliable
Cons: more fuel needed, stove can become unusable due to certain factors, drinking water may taste flat
Tablet/Drops Method
I always carry tablets as a backup during 3-season trips. The possible outcome from losing a filter, breaking it or having it clog without treating water is not one that I want to endure. So this was something that came easy to me as I consider the same possible factors with my stove or fuel in the winter.
Tablets are light, compact and simple to use. With tablets there are a few options out there. Chlorine Dioxide and Iodine.
Chlorine Dioxide takes at least 4 hours to clear impurities such as cryptosporidium. It also needs to be used in warmer temps in order to fully complete the task at hand. Our bodies can consume a fair amount of it. It also has no bad taste and leave my bottles free from staining. These are the tablets, I like to carry.
Iodine is another option. It takes 35-45 mins to clear your drinking water. It is light sensitive and needs to be stored in the bottle from which it is purchased. Some individuals may also be allergic to iodine tablets. Like Chlorine dioxide, iodine also needs to be used in warmer temps (about 68 farenheit) to be effective. The tablets will also give water a slight bitter taste and can cause discoloration to your water bottle over time. Though this can be mostly eliminated by adding Vitamin C after the water has been treated. Juice mixes like Tang can provide this.
Drops like Aquamira can freeze during winter trips as they are liquid so for that sole reason I will not use them at this specific time of year. They are a good option for 3-season though.
Pros: great backup or addition to other methods, effective, lightweight, no part compromises
Cons: takes a long time, human consumption tolerance, drops can freeze, possible water taste/bottle staining
Pump/Filter Method
This method is excellent for 3-season use and is the one I prefer during those times, but in winter it can backfire. Harsh cold temps can crack a filter or worse, you can be left with a portable frozen ice pack. If a paper filter were to be used close to freezing temperature it may be fine, but consider a rapid drop in temperature after using it and then maybe setting it in your pack at camp. Any water that may still be on that internal paper filter can still freeze. This may not only weaken the flow, but can weaken the filter’s strength altogether. For these drawbacks alone I always forgo bringing a pump filter on winter trips.
Pros: none for winter with freezing or below temps (many for 3-season)
Cons: cracked filter, frozen filter, compromised filter
*The MSR Guardian could be a viable option, but I have no personal experience using one out on long winter trips yet.
UltraViolet Method
This method can be another good option during 3-season depending on your location, but with winter there are two factors that keep me from using this one too. They are battery operation and the UV lamp. The fact that some models rely on batteries make it risky for use (at least in my opinion). USB rechargeable options, again may seem great, but I don’t want to use my external battery pack to charge this, my phone and possibly a headlamp. This would deplete the battery pack quicker than intended. One would also have to be careful of the quartz lamp casing to these devices. Yes, they do hold great strength, but they are not indestructible. The UV method can still be used in the winter, but I wouldn’t want to rely on it solely.
Pros: quick, effective
Cons: relies on batteries, possibility of compromised parts
Tricks For Carrying Your Water In The Winter
Wrap Your Nalgene In Duct Tape
A great way to protect your water inside to a certain extent, and carry just the right amount of duct tape instead of carrying a huge roll.
If Carrying A Nalgene, Carry It Upside Down
This trick will help keep the wide mouth lid on your bottle from freezing due to the liquid taking up the space.
Insulate The Hose To Your Hydration Reservoir
Your hydration reservoir should be fine if you have it stored internally as your gear and body heat should protect it from freezing. The same thing that can happen with a water filter in winter can also happen to a drinking tube. Combat this with adding an insulator by the hydration pouch manufacturer. You can also put your gear making skills to the test and make your own at home.
Carry Or Store Your Bottle In A Wool Sock
Those extra socks aren’t just for your feet or as makeshift mitts. I’ve been out many nights in very cold temps and didn’t want extra water to freeze. Tents can only be so warm internally during the winter. I’ll use trick #5 (see below), but will take my other water bottle and slide a sock over it overnight.
Boil Water & Store In Your Sleeping Bag Footbox At Night
This little trick can make a world of difference! Boil water and throw it in a Nalgene (this can also be a great time to add a chlorine dioxide tablet to purify the water if needed). Place the Nalgene in the footbox area of your sleeping bag and you’ll notice some warm heat fill your bag. It won’t add a lot of heat, but it will temporarily act like a little personal space heater. Come morning, you’ll have a cooled down bottle of water ready for drinking or coffee making.
What method do you prefer to use for water treatment during winter backpacking, camping or hiking? What tricks do you like to use when carrying that treated water? Feel free to share them in a comment below.