Treating water in the cold

[Drapac]

Getting ready for a Feb start Nobo and with several of my big ticket items either purchased or at least decided on, I can turn attention to some of the smaller (though equally important items).

I am planning on the worst weather possible, which means freezing Temps. And from what I have read so far, that eliminates water filters.

The question then becomes, how to treat water. I have read about bleach, aqua Mira and tablets but have noticed some differing of opinions on whether they actually kill Giardia cysts.

What is your go to method for winter water purification and do you have any tips that might come in handy?

Also I know some people drink untreated water and have no problem. I plan on treating everything just to play it safe. Risk/reward is to great imo to mess around.

Thanks!

[The Solemates]

If I treat, I use a water filter no matter the temperature. I've never been sick.

[QiWiz]

I would use Aqua Mira drops, tablets, or a Steri-Pen. A Sawyer squeeze can freeze and be permanently damaged as a result. If it gets cold enough, Aqua Mira drops can even freeze, though this does not damage them (though the container can in theory be damaged)

[Drapac]

I would use Aqua Mira drops, tablets, or a Steri-Pen. A Sawyer squeeze can freeze and be permanently damaged as a result. If it gets cold enough, Aqua Mira drops can even freeze, though this does not damage them (though the container can in theory be damaged)

tt


Thanks for the reply. I like the idea of the Steri-pen, but am a little wary of something that can breakdown/run of batteries (though a back up tablet/supply of treatment would do in a pinch I suppose). Do you have any experience with a Steri Pen? If so, roughly how long/how much water were you able to treat on a set of batteries?

[nsherry61]

If I treat, I use a water filter no matter the temperature. I've never been sick.

I probably shouldn't go here, but . . . I rarely treat my water in winter and I've never been sick. Hmm. Of course, I rarely treat my water in the summer either and I've still never been sick.

I have a hard time getting to worried about getting sick from melted snow.

Steripens work well for one or maybe two people, but get kinda slow for more than one unless everyone carries them. Filters really aren't that hard to keep from being frozen if you store them in a Ziploc and keep them in an inside pocket and inside your sleeping bag or inside a roll of cloths or other insulation - it just adds a little "fiddle factor".

In winter, I generally keep a fanny pack against my belly, under my cloths, to keep the things that I want to keep warm, warm and easily accessed. If I'm hiking/skiing/snowshoeing I often keep a water bottle inside my jacket adding snow to it as I drink so it is melting and maintaining my water supply while I move . . . not a good idea if you struggle keeping warm, but a great idea if you are generating lots of heat and have to otherwise strip down to keep from overheating.

[Greenlight]

I'm glad you posted this, Drapac, because I've been mulling it over, too. I took my Sawyer Squeeze on a February overnighter last year, and kept it tied around my neck in a microfiber bag on a cord, and it stayed warm. I had enough water with me that I never had to use the Sawyer (I always chemically treated my water before), but the crux of the matter seems to be, at least with running water...how to get it down to treatable temperature before filtering it or adding the chemicals.

Anyone have any experience?

My gut is telling me to buy a bladder just for winter water. The heat from your back should keep the from freezing, even thought the tube may. It would then be possible to pour that water into another container from which you could filter it into a bottle.

Getting ready for a Feb start Nobo and with several of my big ticket items either purchased or at least decided on, I can turn attention to some of the smaller (though equally important items).

I am planning on the worst weather possible, which means freezing Temps. And from what I have read so far, that eliminates water filters.

The question then becomes, how to treat water. I have read about bleach, aqua Mira and tablets but have noticed some differing of opinions on whether they actually kill Giardia cysts.

What is your go to method for winter water purification and do you have any tips that might come in handy?

Also I know some people drink untreated water and have no problem. I plan on treating everything just to play it safe. Risk/reward is to great imo to mess around.

Thanks!

[nsherry61]

. . . I took my Sawyer Squeeze on a February overnighter last year . . . the crux of the matter seems to be, at least with running water...how to get it down to treatable temperature before filtering it or adding the chemicals. . .

I'm not sure where you are going with this. Do you want to heat up or cool down your running water before you treat or process it? Warm water does seem to filter faster, but nearly freezing water that is liquid still works. Also, chemicals work more slowly in cold water, but they still work. A stove heats water pretty well, but I don't understand the desire to mess with this.

. . . My gut is telling me to buy a bladder just for winter water. The heat from your back should keep the from freezing, even thought the tube may. It would then be possible to pour that water into another container from which you could filter it into a bottle.

Bladders are to fiddly for me, especially in winter. You can get an insulated hose, or insulate your hose to reduce (and/or eliminate) the hose freezing issue if you really want to mess with one.

I really don't understand what you are getting at regarding all the water transfers you are alluding to above. If you are using a Sawyer Squeeze, fill the squeeze bladder and squeeze it into a bottle and be done with it.

[Ktaadn]

I use a sawyer squeeze all year long. When the weather is below freezing, I store it in a ziploc bag in my pocket and I put it in my sleeping bag at night.

As for the bladder/drinking tube, I've had both of them freeze solid. The bite valve now leaks because of it. I just drink straight from my sawyer now.

[Dogwood]

Aqua Mira two part drops yr round in the U.S. In Feb even with the longer activation times not a game changer. Easy, UL, minimal bulk, readily available, effective for the common AT nasties, comparably cost effective.

I probably shouldn't go here, but . . . I rarely treat my water in winter and I've never been sick. Hmm. Of course, I rarely treat my water in the summer either and I've still never been sick.

I have a hard time getting to worried about getting sick from melted snow...

Off topic but this is my mindset as well.

[Dogwood]

but nearly freezing water that is liquid still works.

lol ....

[Mr. Bumpy]

I'll qualify my response with that I have never distance hiked in the winter, but I typically do two or three long weekend hikes each winter -3-5 days for 35-75 miles. I still cary a Sawyer as backup but my primary water purification for winter is boiling. I use the MSR Reactor which is heavier but works faster and is more efficient than a Jet Boil.
Cons are obvious - weight of stove and fuel consumption - this would not be a thing to do with an alcohol stove, (nor would I want to do it with a pocket rocket or giga) but a Jet Boil would do just fine. Two canisters would last about a week but you would be walking through a resupply point at least once a week even that early in the season so supply wouldn't be a problem. Boiling also takes a little bit more time than filtering, but it is winter and there will be a lot of sit around time so this give you something to do. I like that I don't get my hands cold messing around with the filter and that there is always something warm around to handle or drink.
If you are willing to take the weight penalty of a Jet Boil type of stove then think about this. Like I said, I have only done this for 3-5 days at a time, but even if I were starting a distance hike on the AT where supply is not an issue, it is how I would handle water purification.

[Greenlight]

Here's my concern, with the Sawyer products. They advertise that if you allow the filter to freeze, you should throw it away because the membrane is compromised. If you are collecting running water in the winter, chances are that the water is below 32 degrees Fahrenheit. When you go to filter it, as soon as it contacts the membrane, the water may turn to ice. You've just destroyed your Sawyer.

A potential solution, since you can wear your Sawyer next to your skin to keep it from freezing, and can warm freezing water up in a bladder that is next to your back in your pack, is to transfer the unfiltered water int the bladder into a container from which it can be filtered into a bottle.

The same water would also be warmer and allow AquaMira to work more quickly if you didn't want to use a filter.

All of this is considering that you take treating your water seriously instead of simply drinking it untreated. Do you think I'm over-reacting to Sawyer's own claim that a frozen filter should be thrown away? Do you think I'd be okay filtering water with my Sawyer, which has been kept above freezing because it is always next to my skin, then shaking it until it stops dripping, then put it back in it's pouch next to my skin? I just don't want to *think* I'm filtering water, when in reality all I'm doing is running it through a broken filter.

I'm not sure where you are going with this. Do you want to heat up or cool down your running water before you treat or process it? Warm water does seem to filter faster, but nearly freezing water that is liquid still works. Also, chemicals work more slowly in cold water, but they still work. A stove heats water pretty well, but I don't understand the desire to mess with this.


Bladders are to fiddly for me, especially in winter. You can get an insulated hose, or insulate your hose to reduce (and/or eliminate) the hose freezing issue if you really want to mess with one.

I really don't understand what you are getting at regarding all the water transfers you are alluding to above. If you are using a Sawyer Squeeze, fill the squeeze bladder and squeeze it into a bottle and be done with it.

[Flounder940]

I probably shouldn't go here, but . . . I rarely treat my water in winter and I've never been sick. Hmm. Of course, I rarely treat my water in the summer either and I've still never been sick.

I too rarely treat water. Unless I am getting water from a stream that I know is close to a farm or field that has livestock, I don't treat. I've never been sick either.

[colorado_rob]

Yours is a valid concern greenlite, but how can liquid water be below freezing? The water might be just barely above, but not below.I believe that if you keep your sawyer warn before, plus shake it out when done and store next to body, religiously, you'd be fine. There is no mechanism to freeze, as long as you're quick about it.

All this being said, i use aqua mira even in deep winter. And i don't see any reason to treat melted snow with anything, though the taste is usually weird.

I got giardia once, diagnosed, travelling to belieze. Not fun, but not the end of the world either. Thankfully it take a while for symptoms to show up so didn't ruin our dive trip.

[Dogwood]

Based on my understanding some of the more common AT water borne parasites are less active or less widespread in winter. Less people equals less problems less domesticated pets related to diseases humans and our activities transmit via water. Less wildlife activity too that transmit diseases.

[Dogwood]

Actually, pure water can still be in its liquid state below 0* C. H20's freezing pt is atmospheric pressure dependent. Like air water can contain all sorts of elements or compounds in it. For example adding common salt to H20 changes the freezing pt.

[Dogwood]

For instance, I've dropped a thermometer in alpine(high elevation) running/liquid water to find the temp of it to be in the 20's* F.

[Starchild]

In cold temperatures pathogens can't multiply fast and water generally safer, so less worries about purification.

Steripen should also be kept warm if possible. Though no harm if it gets cold, expect it may need to warm up to work (particularly the Freedom model)

.... I use the MSR Reactor which is heavier but works faster and is more efficient than a Jet Boil......

IIRC yes the Reactor is faster, the Jet Boil I believe is more efficient (reactor is faster because it uses more fuel). Both are by a very small factor as to be practically meaningless. The smallest reactor is the most inefficient, but again the difference is small. The reactor can be used as a great hand warmer radiant heat source.

With all that said both will start to underperform when the temps fall into the teens and lower due to the properties of the gas in the canisters, there are ways around that too.

[Drapac]

Thanks for all the replies.

First off, yes there is probably a reduced risk of contamination in the winter, but I am not taking any chances.

Same deal with a filter. Water expands when frozen and I have read and a would have assumed anyway, that that can wreak havoc on a filter. The biggest thing for me, is not knowing if it's working or not.

Sounding more and more like AM may be the way to go.

Does anyone know if the steri pen takes longer to work in the cold?

[Another Kevin]

If I'm using running water in the winter, Aqua Mira two-part treatment.

If I'm melting snow, I've got a heat source going already. I might as well boil it.