Water Treatment

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DayTrip

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Between the recent AMC warning about water quality near NH/ME border and now a few posts on hiking forums about becoming ill in other areas I'm wondering if the increased hiker volume the past few years is to blame or if it is a naturally occuring bacteria to blame for the recent "outbreak". Does anyone have more info or links to more details on the situation? I guess my big question is if a water filter is not getting the current bacteria out of water what else short of boiling the water can be done in a reasonable time frame (don't tablets take hours)?

I don't filter water a lot but I've been doing longer hikes/some overnights and part of keeping the pack weight down hinges on water management. I use a Sawyer filter and haven't had any issues. Curious what everyone's "routine" is for water treatment.
 
Aquamira and proper technique is my choice.

Bad technique is another means of contamination, if the water is clean the bad technique is reinforced so when it does matter its a surprise to a hiker . Many folks mix "clean" bottles with "dirty bottles" and many don't rinse the caps threads off.

Many but not all clusters of bad water frequently occur at off trail water sources.

I remember one major water bourn illness outbreak when I was sectioning that was reported plus or minus 100 miles of Dragons Tooth in VA. It turned out a gas station right near the AT at a road crossing had a cross connection in their piping so their water supply was contaminated. It took weeks to trace it back to that spot and there were warnings everywhere. Some folks develop a tolerance to contamination and it doesn't bother them (or they just don't drink the water) Hikers would fill up as they hiked by in either direction and get sick a few days later and blame it on backcountry sources. I am not pointing fingers but a hostel along the way in Maine could have contaminated water. One of the down sides of hostels are that they typically are private homes and there are no regulations. A squirrel could be floating in the well and no one may see it for weeks.
 
Aquamira and proper technique is my choice.

Bad technique is another means of contamination, if the water is clean the bad technique is reinforced so when it does matter its a surprise to a hiker . Many folks mix "clean" bottles with "dirty bottles" and many don't rinse the caps threads off.

Many but not all clusters of bad water frequently occur at off trail water sources.

I remember one major water bourn illness outbreak when I was sectioning that was reported plus or minus 100 miles of Dragons Tooth in VA. It turned out a gas station right near the AT at a road crossing had a cross connection in their piping so their water supply was contaminated. It took weeks to trace it back to that spot and there were warnings everywhere. Some folks develop a tolerance to contamination and it doesn't bother them (or they just don't drink the water) Hikers would fill up as they hiked by in either direction and get sick a few days later and blame it on backcountry sources. I am not pointing fingers but a hostel along the way in Maine could have contaminated water. One of the down sides of hostels are that they typically are private homes and there are no regulations. A squirrel could be floating in the well and no one may see it for weeks.

I assume by a "clean bottle" you mean a bottle you've put nothing but filtered water/trusted water (like from your home) in yes? And when you say "wipe the threads" are we talking about the filter bag the filter screws onto? I use the Sawyer style filter so I generally fill the bag, then wipe my hands, the threads and the filter (with protective cap still covering the outlet) with a paper towel that I bag and then remove cap and squirt into the clean bottle. Is that what you're considering to be proper technique? The first couple of times I filtered water I wore disposable surgical gloves to do this and filtered the water through a coffee filter (a tip I had read somewhere - which does work but is a huge pain in the ass). The next few times I ditched the gloves and filter and used hand sanitizer after wiping and before squirting into clean bottle. That is my current "technique". Am I destined for diarrhea? :p
 
"Bad technique" can also mean self-contamination by a fecal/oral route. We sometimes make too much of a point of filtering our water but then use a privy with no handwashing or hand sanitizing. This might be instructive: http://adirondoc.com/publications/water_quality_2004.pdf I suspect it has already been posted to this forum somewhere.

Note the following points: "...we need to realize that, despite unsubstantiated anecdote to the contrary, there is no good epidemiologic evidence that North American wilderness waters are inherently unsafe for consumption." (Yet it's good business to encourage the spread of the unsubstantiated anecdotes if you are trying to sell water purifiers.) And: "It must be impressed upon backpackers (just as it is impressed upon health care, food industry, and daycare workers) that stopping hand-to-mouth spread is the key to preventing gastrointestinal infection. Diluting this message with unfounded concerns about wilderness water quality or the relative merits of various water-treatment methods serves no useful purpose."
 
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Filters add a lot of complexity to using proper technique and that's why I don't use them. I don't wipe off threads. I mix the water with aquamira, tighten the cap, shake the bottle then loosen the cap and squeeze the bottle so that water leaks around the cap threads. Carbon type filters do have value in areas with chemical contaminants although I believe that their effectiveness for chemical removal is limited before the pores have saturated. They may still work as barrier type filters for biological nasties(like Giardia and Crypto) even though their chemical removal capability is gone. I do agree that filters can clean up murky water that would otherwise be unpalatable albeit the trade off is that the element needs to be backflushed more frequently. Given the general reliable water source in New England, I just wait for better water to treat.

I wont take the bait from the prior poster on the relative cleanliness of backcountry water and its potential as vector for contamination, There are studies on either side of the fence and hundreds of threads on the internet debating the pros and cons. I do agree that poor hand to mouth sanitation is probably a far more likely method of transmission. Unfortunately hand sanitizer reportedly has no effect on Norovirus which has been the bane of the AT for the last few years. Ultimately, not treating water is rolling the dice with great odds especially if the gambler is a healthy individual.
 
"Bad technique" can also mean self-contamination by a fecal/oral route. We sometimes make too much of a point of filtering our water but then use a privy with no handwashing or hand sanitizing. This might be instructive: http://adirondoc.com/publications/water_quality_2004.pdf I suspect it has already been posted to this forum somewhere.

Note the following points: "...we need to realize that, despite unsubstantiated anecdote to the contrary, there is no good epidemiologic evidence that North American wilderness waters are inherently unsafe for consumption." (Yet it's good business to encourage the spread of the unsubstantiated anecdotes if you are trying to sell water purifiers.) And: "It must be impressed upon backpackers (just as it is impressed upon health care, food industry, and daycare workers) that stopping hand-to-mouth spread is the key to preventing gastrointestinal infection. Diluting this message with unfounded concerns about wilderness water quality or the relative merits of various water-treatment methods serves no useful purpose."

Interesting read. Thanks for the link.
 
When backpacking/camping, we carry a filter and are very careful about the sanitation of the device itself. When dayhiking we try to carry enough water/fluids for the day but do have iodine tablets. The iodine tablets have a limited shelf life so replace them periodically. The tablets themselves could become a health risk for some individuals if used excessively.

As for taking a chance on a water source, think of the old on-line bank ad with the punchline, "What's in your wallet!?" What's in your water? A look at the source is all that is needed sometimes to convince you to treat but how about a clear cool mountain stream ... what might have been spread by wildlife upstream. Sometimes you feel lucky, sometimes you don't, or aren't. We've felt lucky at a clear spring many a time.
 
Filters add a lot of complexity to using proper technique and that's why I don't use them. I don't wipe off threads. I mix the water with aquamira, tighten the cap, shake the bottle then loosen the cap and squeeze the bottle so that water leaks around the cap threads. Carbon type filters do have value in areas with chemical contaminants although I believe that their effectiveness for chemical removal is limited before the pores have saturated. They may still work as barrier type filters for biological nasties(like Giardia and Crypto) even though their chemical removal capability is gone. I do agree that filters can clean up murky water that would otherwise be unpalatable albeit the trade off is that the element needs to be backflushed more frequently. Given the general reliable water source in New England, I just wait for better water to treat.

I wont take the bait from the prior poster on the relative cleanliness of backcountry water and its potential as vector for contamination, There are studies on either side of the fence and hundreds of threads on the internet debating the pros and cons. I do agree that poor hand to mouth sanitation is probably a far more likely method of transmission. Unfortunately hand sanitizer reportedly has no effect on Norovirus which has been the bane of the AT for the last few years. Ultimately, not treating water is rolling the dice with great odds especially if the gambler is a healthy individual.

How long do you wait for the Aqua Mira tablets to "work"? Read several threads about this on other forums and there does not appear to be much of a consensus - 30 minutes to 4 hours depending on water temp. That is quite a variance. I have (2) 64L Sawyer pouches which I am considering using to replace my Nalgenes (the bags are much lighter but I'm worried about caps staying threaded on). If I can stop at a river, tank up my Sawyer bags, drop the tablets in and then within 60 minutes use the Sawyer filter to produce drinkable water that would be an ideal set up.

Related to that, do the tablets completely dissolve? i.e. will there be any kind of leftover sediment that would clog the Sawyer filter if I do in the prescribed manner? Thanks for the feedback
 
"Bad technique" can also mean self-contamination by a fecal/oral route. We sometimes make too much of a point of filtering our water but then use a privy with no handwashing or hand sanitizing. This might be instructive: http://adirondoc.com/publications/water_quality_2004.pdf I suspect it has already been posted to this forum somewhere.

Note the following points: "...we need to realize that, despite unsubstantiated anecdote to the contrary, there is no good epidemiologic evidence that North American wilderness waters are inherently unsafe for consumption." (Yet it's good business to encourage the spread of the unsubstantiated anecdotes if you are trying to sell water purifiers.) And: "It must be impressed upon backpackers (just as it is impressed upon health care, food industry, and daycare workers) that stopping hand-to-mouth spread is the key to preventing gastrointestinal infection. Diluting this message with unfounded concerns about wilderness water quality or the relative merits of various water-treatment methods serves no useful purpose."

My takeaway from this article is that in most places in the backcountry, treatment of water is not necessary, however in places of high use, such as Marcy Dam or Hermit Lake, it might be prudent to treat the water. Most importantly, wash your hands! (Since soaps are a no-no, hand sanitizer is probably best.)
 
I don't use the Aqua Mira Tablets, I use the two component liquid system that requires mixing two liquid components in a cap. I then have to wait for 5 minutes until it kicks off (turns green and has a detectible odor) then it gets dumped in the water bottle. I agree that the time to treat does not seem to be hard and fast. In normal backpacking weather I try to stay ahead one bottle and usually shoot for 1 hour minimum. I have heard of much longer treatment times for crypto, luckily that seems to be more prevalent with herd animals (dairy farms). I do on occasion double dose if the water is cloudy or suspect. The nice thing with chlorine dioxide is that it breaks down into tis components rapidly eventually turning into sodium chloride (salt).
 
For day hikes I carry all the water I need in a bladder system.
For over nights and extended trips I use a First Need Purifier.
The problem with filters is that they are only filters and not water purifiers. They merely remove large organic particles from the water. You still need to treat or boil the filtered water in order to purify it. You do not save any weight or space with this system.
The problem with chemical treatment only is that you often drink greenish water that has a certain flavor to it. The positive is that this is the lightest option and takes up next to no space in the pack.
If you use a water purifier like a First Need Pump you eliminate the bacteria, cysts and viruses including giardia and cryptosporidia. No crypto and no waiting for chemicals to work. Simply pump an water is pure, clear and has no off taste. Trade off is size and weight.
While it may well be true that most of the water in the wilderness is inherently safe to drink. You will be really glad you pumped your water through a purifier when you find an animal carcass rotting upstream from your camp.
You just never know what is just around the corner.
 
A "best" treatment is filtration to remove bacteria and cysts followed by chemical treatment (eg >= 1ppm iodine*) to kill viruses. If there is chemical contamination (eg salt, heavy metals), then treatments such as distillation may be required.

* Purifiers often combine filtration with iodine.

Boiling is low-tech but highly effective.

Since I mostly dayhike in the NE, I generally carry all the water that I will need but also carry tincture of iodine in case treatment seems prudent.

Medicine for Mountaineering by Wilkerson et al has a good informed discussion of a variety of methods for treating water. There are also many prior threads on the topic, many of which contain good info,

Doug
 
For day hikes I carry all the water I need in a bladder system.
For over nights and extended trips I use a First Need Purifier.
The problem with filters is that they are only filters and not water purifiers. They merely remove large organic particles from the water. You still need to treat or boil the filtered water in order to purify it. You do not save any weight or space with this system.
The problem with chemical treatment only is that you often drink greenish water that has a certain flavor to it. The positive is that this is the lightest option and takes up next to no space in the pack.
If you use a water purifier like a First Need Pump you eliminate the bacteria, cysts and viruses including giardia and cryptosporidia. No crypto and no waiting for chemicals to work. Simply pump an water is pure, clear and has no off taste. Trade off is size and weight.
While it may well be true that most of the water in the wilderness is inherently safe to drink. You will be really glad you pumped your water through a purifier when you find an animal carcass rotting upstream from your camp.
You just never know what is just around the corner.

This is what I have historically done but in summer, especially on hot days, I have no problem drinking 4-5 L of water and still not having light yellow/clear urine. That is a HEAVY weight in the pack. I have also started overnighting a bit again and when you add all the other stuff in the pack in addition to the water (and even more water for cooking) it seems like filtering and getting water as I go (where it is possible) is highly desirable. I'm planning on going out on a "light" day hike this weekend and filtering extensively to see how it affects my stamina hiking (lighter pack) and overall time (screwing around with the filter at river crossings). The recent news headlines had me doing a bit of a review of what I've done in the past. There seems to be a lot of disagreement on the so called "best" water purifier so I was curious what everyone's process was. The Sawyer filter I use is a pretty light and convenient system.
 
I don't use the Aqua Mira Tablets, I use the two component liquid system that requires mixing two liquid components in a cap. I then have to wait for 5 minutes until it kicks off (turns green and has a detectible odor) then it gets dumped in the water bottle. I agree that the time to treat does not seem to be hard and fast. In normal backpacking weather I try to stay ahead one bottle and usually shoot for 1 hour minimum. I have heard of much longer treatment times for crypto, luckily that seems to be more prevalent with herd animals (dairy farms). I do on occasion double dose if the water is cloudy or suspect. The nice thing with chlorine dioxide is that it breaks down into tis components rapidly eventually turning into sodium chloride (salt).

From what I read on the Aqua Mira site and other forums it didn't appear to make a difference in time or efficacy using the drops or the tablets. The tablets seem more convenient. Was there a specific reason you chose the liquid over the tablets or is that just how you happened to start using - dissolving time, tablets don't fully dissolve, etc?
 
Bad technique" can also mean self-contamination by a fecal/oral route.

I'm trying to think of a pathogen for which *self*-contamination (as opposed to scenarios like food preparation, where a carrier can transmit to *others*) is a serious concern, and I'm coming up blank. There's probably some scenario where you could make an existing infection worse (or at least longer duration)... tapeworms maybe? But the point is, pathogens don't spontaneously generate in your poop. If you're not already carrying the pathogen, you won't get it by eating your own poop.

There's a large world of pathogens out there, so maybe it's possible to be an asymptomatic carrier of something until you trigger a symptomatic infection via "bad technique" , but is that something anybody ought to be worrying about?
 
Price per dose and how long an opened package will last is why I use the drops. I would expect an open tablet container would deteriorate once opened. The drops seem to last years and its easy to check if they are still working as once mixed they form a green color and there is definite chlorine smell. (brings me back to my pulp mill days). One of the early competitors for the drops had an intermediate container that a hiker would premix a dose for a day. I don't think the method caught on. Once you are used to mixing a dose first thing when you stop the 5 minutes isn't that long.

Portable Aqua tablets specificly state that they are only good for 30 days after opening.
 
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On the other hand, PolarPure, being pure elemental iodine crystals, has an indefinite shelf life. One small bottle should last long enough to treat up to 2,000 liters of water. I've had the same bottle for more than 20 years, and it is still good with plenty of crystals remaining, and I have never had any problems treating water. Tastes like iodine, but it is effective and extremely simple to use, and there is no fussing around with pumping or batteries or mixing of multiple chemicals.
 
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I changed to the Sawyer squeeze filter last summer, and used it for 5 weeks straight in Colorado. It worked just fine for me.
 
Price per dose and how long an opened package will last is why I sue the drops. I would expect an open tablet container would deteriorate once opened. The drops seem to last years and its easy to check if they are still working as once mixed they form a green color and there is definite chlorine smell. (brings me back to my pulp mill days). One of the early competitors for the drops had an intermediate container that a hiker would premix a dose for a day. I don't think the method caught on. Once you are used to mixing a dose first thing when you stop the 5 minutes isn't that long.

Portable Aqua tablets specificly state that they are only good for 30 days after opening.

According to the site each tablet is individually packaged and stored within a "master" zip pouch. I'll have to go back and check to make sure I read that right. Thanks!
 
On the other hand, PolarPure, being pure elemental iodine crystals, has an indefinite shelf life. One small bottle should last long enough to treat up to 2,000 liters of water. I've had the same bottle for more than 20 years, and it is still good with plenty of crystals remaining, and I have never had any problems treating water. Tastes like iodine, but it is effective and extremely simple to use, and there is no fussing around with pumping or batteries or mixing of multiple chemicals.

I clicked through to this site and there is a notice that they do not make this anymore.
 
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