Water treatment question.

[heyman62]

This is our first year of multi-day hiking. We were planning on just treating our water, but I was wondering what you experienced hikers thought of this. I was thinking of of passing our water thru a simple 25 micron filter without a pump system. Made a homemade filter of 25 micron nylon. This is just big enough to allow water to pass thru. I hear about pump filtering systems(that cost bucks) sometimes breaking while on a hike. Do any of you filter without a pump? What size pores do you filter with?

[stickman]

I believe that lots of things that can harm you are smaller than 25 microns (eg. the hepatitis virus, cryptosporidia, and probably some bacteria). What you are suggesting should remove most sediment and silt, but it won't purifiy the water. That should be OK if the water source is more or less pristine and protected, but not otherwise. When the "safety" of the source is uncertain to me, I use Aguamira drops. Probably weighs about two ounces to purify 30 liters of water. Sure, the whole process takes 20 minutes before you can drink, but your filter cloth is going to take a while as well, for far less protection, IMO.

Stickman

[Green Bean]

check out katadyns website. THey have some good water treatment products. not to pricy ~GB

[TN_Hiker]

In order to "capture" most protozoas you going to want something that filters much smaller. I know that Giardia cysts are approx. 3 microns in size. You can be assured 25 microns is not going to capture any microbes.

[SloHiker]

I think the industry standard is something like 0.2 to .03 microns for "filtering" devices. There are several gravity fed systems out there that do not require "pumping". Personally, I prefer the convenience of a pump and I have never worried too much about the reliability factor if you use common sense. Some folks swear by their gravity fed systems, though.

[SloHiker]

typo....0.3 not .03 microns

[Phreak]

I use the First Need Deluxe Purifier (http://www.generalecology.com/portablesystem.htm#1). It's a little heavy at 15 ounces but I'd rather have it along with me and cut some weight elsewhere. I have a sensitive stomach and can't risk the chance of contracting something on the trail.

[TN_Hiker]

The First Need Purifier is what I use as well. Which brings up the point....there is a difference between a water purifier and a water filter.

[orangebug]

If you are worried about cryptosporidium, more commonly encountered in city tap water, a 1 micron filter or less is recommended by the CDC.

Of course, some of us don't think that water treatment is more than a marketing scheme for chemicals or gear. Your individual situation may dictate a necessity for treatment, for instance if you are immune compromised.

[SloHiker]

"Purification" usually is done by mechanically (filtering) and chemically treating the water to get rid of the bad stuff. Viruses, for example (not commonly found in U.S. water sources I'm told) cannot be generally "filtered", but must be treated chemically.
This thread brings up something worthy of mention; whe I was a kid growing up in FL, I routinely drank from streams, rivers, lakes and garden hoses (a good source of "bugs" in hot weather) with absolutely no ill effects because my system was accustomed to the exposure. But, having refrained from that for a number of years, I'd likely get sick the first time I did it today from lack of that "exposure" to waterborne bugs.

[Footslogger]

[quote=SloHiker]"Purification" usually is done by mechanically (filtering) and chemically treating the water to get rid of the bad stuff.
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Hmmm ....my understanding is just the opposite. Guess old dogs can learn new tricks.

I've always thought of water treatment in terms of "Filtration" and "Purification". To me, Filtration was the mechanical removal of stuff from the water and Purification was treating the water to kill stuff in the water.

Based on my understanding of the two terms, I don't Filter because I use a chemical treatment (AquaMira) which kills (Purifies) the bugs (hopefully) and keeps me from getting sick.

Aw who knows ...maybe it's all symantics.

'Slogger

[SloHiker]

Naw, you're more right than I am in the verbage used. Purification doesn't necessarily go hand-in-hand with mechanically filtering the water. My boo-boo.

[Hikes in Rain]

Just to continue the symantics game, what Footslogger described is actually "disinfection", or killing the crawlys in the water. Even purifiers such as the First Need mentioned above (highly recommended by me, especially if the water source is suspect, such as the effluent of an industrial waste treatment plant) don't really "purify", or turn your water into nothing but pure dihydrogen monoxide. Even the best purifiers leave dissolved minerals and such, which is a good thing, as it provides taste. (Ever tasted distilled water, which is pretty much "pure'?)

Most of the waters on the trail I've encountered in the South are relatively pristine, needing only disinfection. however, years of working as both an environmental engineer and a medical technologist have made me pretty paranoid about water-borne diseases. Getting Giardia up in Alaska (of all places!) didn't help that paranoia, either, so I tend to go overboard.

[Footslogger]

[quote=Hikes in Rain]Just to continue the symantics game, what Footslogger described is actually "disinfection", or killing the crawlys in the water.
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This is getting fun. So then water can be "pure", having been passed through a purifier ... but still "infected" ??

'Slogger

[Hikes in Rain]

Hmm. Interesting concept. Sometimes you guys are just way too smart! But yeah, I think you're right. Imagine distilled water that's got some sort of bacteria, for example, growing in it. (Heaven only knows what they're living on, though, since by our definition there aren't any nutrients in the water). The water is pure, but has biota living in it.

Reminds me of one of Niven and Pournelle's books, based on what was probably the simplest ecosystem ever discovered. Algae, a species of frog with rather disgusting habits and their tadpoles.

[Footslogger]

[quote=Hikes in Rain]The water is pure, but has biota living in it.
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But all biota ain't bad biota ...correct ??

'Slogger

[Almost There]

Just screw the filter or treatment and take a chance. Who knows? You could gain a friend in the process!

[Hikes in Rain]

Absolutely not! Most are pretty harmless, some are even beneficial. The saccromyces yeast, for example, is what gives us beer, wine and bread, and is one of the primary sources of B vitamins. You currently have several pounds of various microbes living in your intestine, without which digestion would be compromised. Way back when I was working in hospitals, one of the old doctors told me about giving premature babies little enemas of their mother's, er, solid excrement because the little guys were's able to develop their own.

With the exception of certain disease pathogens, most organisms cause problems only because they're flourishing in an area we'd rather they didn't, such as in our food, drink or open wounds.

[heyman62]

Well we all seem to agree those buggers will get thru smaller than my 25 micron filter. I just want to remove sediment really. I fully intend to treat and gladly wait 30 minutes or more to make sure those buggers are DEAD! Thanks for all your insight!

[Hikes in Rain]

Glad we could confuse you further. ;) But yeah, using what you were describing should remove sediments nicely.

[Boat Drinks]

I use the First Need Deluxe Purifier (http://www.generalecology.com/portablesystem.htm#1). It's a little heavy at 15 ounces but I'd rather have it along with me and cut some weight elsewhere. I have a sensitive stomach and can't risk the chance of contracting something on the trail.


I'd like more feedback on this system if y'all don't mind.
http://www.generalecology.com/firstneeddelux.htm#FirstNeed

Seems to me the only drawback is the weight, your thoughts?

[hopefulhiker]

I tried passing water just through a bandana to get out the floaties.. It just took too long.. I treated and drank the floaties after awhile....

[highway]

Floaties mostly sink, being decayed vegetation. Just let it sit for a while and pour if you are stopped, filter through teeth if moving and spit out larger pieces. Just dont be so obsessed with it.