Water filters and treatment discussion..Part 1, source and filters.

[Lawn Sale]

Clown, I would say both. While someone with a deficient immune system will obviously be more at risk, healthy people can still be affected. One thing I'd like to note here, and you just reminded me about it, is that public water supplies, and the rules in general, are based towards the best possible water for 99% of the population, so they err on the side of caution, as they should. You and I hiking are only concerned about one person, ourselves (or a family/group if you're together), so we may choose to take more risks, and we have the leeway to do just that. Water suppliers don't have that option.

paul ron, I agree with you. The filter I was thinking about when I mentioned that was the Miniworks/Waterworks that attach directly to the top of a Nalgene. With the cover in place, the is virtually no cross contamination possible, unless its from your hands.

DougPaul, the test strips I mentioned are a good way to check for the free chlorine residual in the water. No matter what the demand, the strips will tell you what the residual is, so you can determine if you need to add more chlorine or not. Unfortunately these only work for chlorine at present. MIOX uses these same strips as part of their "package", but they have their ownlabels on them. If you're using chlorine, it's a good way to keep everything in check so you don't add too much or too little.

Aviarome, you are correct. There is no evidence to say heavy contamination exists in all areas, but there are select sources, hence the need for prudence, at least in my eyes.

Something else I would like to add is that a lot of the information gathered is fact and some is my personal opinion. The facts speak for themselves, the size of the organisms, the possible presence in water supplies, and the filters. But, those that are my opinions should be taken as such, my opinions. I'm not trying to get everyone to filter their water, I just want everyone to have the facts as they are so they can make their own decisions. It honestly does not matter to me if people filter/disinfect, they are free to do as they choose, and I won't think less of someone who does or does not. I just didn't want people to assume this is my way of trying to get people to do something over something else.

 

[sardog1]

5. Ultra-Violet (UV) aka Steri-Pen. A light emitted at 254 nanometers through a quartz sleeve for a specific amount of time. The light disrupts the DNA sequence of the organism so it cannot reproduce and thus dies off.
a. Pros: Forms no harmful byproducts, water quality from a taste and sight perspective remains unchanged, fast rate (in about a minute).
b. Cons: Certain compounds in the water can absorb the light, making it less effective; dependent on batteries and the unit not breaking down, turbid water can prevent organism destruction by hiding in the shade of the particles, costly ($150), limited life span on the bulb, not sure if it can be replaced (but the bulb life span on other UV systems is very high), does not inactivate certain virus strains.
c. Giardia and Crypto: Effective against Giardia and Crypto.​

All in all, a most excellent article and a real service -- KUDOS!

FYI, a pre-filter is available from the SteriPEN maker for $9.95 that removes light-blocking particles before the light is applied. The bulb can be replaced, but the programmed life span (about 4.5 years of thrice-daily use) far exceeds the likely use by any but the most hardcore hiker or traveller. (The actual tested life span of the bulb is about double that.) You can read lots more details at SteriPEN FAQ.

I know several users, one of whom uses his regularly in the Whites in the winter. He keeps the batteries warm and pulls them out only when needed to treat water. Note the manufacturer's recommendation to use NiMH batteries, NOT lithium or alkaline, in cold weather.​

 

[Pete_Hickey]

....raw wggs...

But then I'm not worried about hikers pooping or critters decomposing in my fridge or near my egg basket.

'y point was that we've developed a fear of germs. Things that we used to do, are no longer acceptable. Look at all the disinfectant soap available these days. What did we do before? You'll get salmonela if your eggs aren't cooked enough.... Ever get runny yellow eggs at MacDo's.

How much of this water filter stuff is because the water is really worse, and how much because you're just more 'aware'?

If you have a 50-50 chance of getting giardia, do you treat water?
What if a 1% chance. How about 0.001% How about 0.00001%
Yes, there is a CHANCE there is something in the water, but what is
that chance.

What about the 'Dear Abbey Syndrome": "If it saves one life it's worth it." "It's better to be safe than sorry."

When questioned about my aluminium foil hat, I'll tell you it's to protect me from both the alien and government mind rays. You may think I'm crazy, but IF THEY EVER INVENT the mind rays, who'll be laughing then? It's better to be safe than sorry.

 

[lumberzac]

How much of this water filter stuff is because the water is really worse, and how much because you're just more 'aware'?

Very good point, but doesn't it also stand to reason that there are far more people in the backcountry than there used to be which in turn would increase the chance that water could become contaminated? I’m not sure what the answer is, but I plan to keep on treating my water as I have in the past.

 

[griffin]

'y point was that we've developed a fear of germs. Things that we used to do, are no longer acceptable. ...

How much of this water filter stuff is because the water is really worse, and how much because you're just more 'aware'?

I did understand your point. Mine was that there are usage issues that, imo, make caution about one's water source seem less like over-reactive fear of germs. (and I"m sorry if my attempt at humor came of as a swipe at you, it wasn't meant that way) - especially since most places we get water in the woods see a fair amount of human traffic.

I do wish there were more solid data on water quality in the area, and yes, if that data were available and the risk was proven small enough, I'd consider skipping the filtration. As it is, 16oz added to the pack seem a reasonable enough precaution against what could be weeks of gastrointestinal misery.
We all have our own risk tolerance, I guess.

 

[danno]

I know several users, one of whom uses his regularly in the Whites in the winter. He keeps the batteries warm and pulls them out only when needed to treat water. Note the manufacturer's recommendation to use NiMH batteries, NOT lithium or alkaline, in cold weather.

A note on Cold Weather Use from the SteriPEN user manual (from their site):

If SteriPEN™ is at a temperature below 32°F/0°C it should not be used. Bring SteriPEN™ up to a temperature above 32°F/0°C before using.

This is in addition to cold weather battery performance. The SteriPEN itself needs to be above 32 degrees to work properly.

 

[sardog1]

Thanks for the correction -- I now recall that he keeps the whole unit inside his clothing when he needs to use it.

 

[darren]

As for proper use, I am talking about how people handle their filters in the field. They rinse off their hands in the potentially contaminated water, then filter water into a bottle which is handled with the same contaminated hands.... After using the filter all the hoses are handled causing contamination to the user and they are stored in the same bag where contaminated water comes in contact with both the clean hoses and filter body ... Not many people are aware of their infection control habbits.

A very important point. I always store the filter's outlet side hose in a zip lock bag which is kept seperate from the rest of the filter. It is a good habit to get in.

- darren

 

[DougPaul]

After using the filter all the hoses are handled causing contamination to the user and they are stored in the same bag where contaminated water comes in contact with both the clean hoses and filter body.

One of the nice things about the MSR Mini-Works and Works filters is that they screw directly onto a Nalgene bottle (or Nalgene fitting on a bladder) and have a cover for the clean end of the filter. (No clean hose required if you attach the filter directly to the bottle/bladder.) Makes it a bit easier to avoid contaminating the clean portions of the system.

Doug

 

[jrichard]

contamination

Speaking of contamination from rinsing hands and then touching hoses, bottle rim, etc... This is probably a small amount of water/contamination.

Considering the amount of water I end up swallowing when rolling a kayak, I wonder if it is worth bringing a filter on kayaking trips! Even when canoeing, there's splashing, touching the paddles, even purposely dunking my hands!

 

[Woody]

I usually use my MSR mini-works filter although I have drank water directly from streams in the Whites when I felt the chance of comtamination was low. I've been lucky and have never gotten sick.

 

[DougPaul]

Considering the amount of water I end up swallowing when rolling a kayak, I wonder if it is worth bringing a filter on kayaking trips! Even when canoeing, there's splashing, touching the paddles, even purposely dunking my hands!

According to http://lomaprieta.sierraclub.org/pcs/articles/giardia_2003.pdf studies have shown that one has to ingest 10 or more cysts to have a reasonable probability of contracting giardia. So pull out when you reach 9...

Doug

 

[Lawn Sale]

Giardia & Crypto

While I work in the water industry, I am by no means an expert on Crypto or Giardia, so I did some research on the issue to become more familiar with the nuances of each organism. Actually I devoted quite a number of hours to this research, but it's always good to expand ones knowledge base, and you guys are worth it. I found some interesting items, some of which I knew, but some of which was unknown to me. The CDC and EPA have some information on their websites, but a significant amount of information came from Britain, where extensive research was done to combat the growing problems over there.

This is not designed to be a scare tactic, but I found some interesting tidbits of information. I also found conflicting reports on the adaptability to Crypto, where some publications say you can build up a resistance to it and some say you cannot. The information I have at work (c.1995) says you cannot, but it’s a topic in constant evolutionary flux, so I don’t know which one is correct.

Cryptosporidium:

Cure: Cryptosporidiosis has no cure so there are no medicines that can be prescribed.

Length of illness: The positive side is that it will usually run its course in 3 to 4 weeks, but the person can still be infectious for another 6 to 8 weeks.

Infection rate: Higher infection rates are associated with younger age children (less than 5 years old), warm, wet weather, and overcrowding near sources.

Infection requirements: Normal infections are thought to require 100 oocysts, but as few as 2 have shown to be infectious in controlled tests on certain individuals. Severity and course of the illness are determined by host immunocompetence (I also learned a new word!).

Symptoms: Symptoms include diarrhea, abdominal cramps, malabsorption, and weight loss, and they show up between 2 and 14 days after infection, with an average of 7 days. Symptoms resemble food poisoning, so it often goes unchecked. It is usually a severely debilitating illness and may cause death.

Survivability in the wild: They can survive for months in soil under cool dark conditions, for up to a year in low-turbidity water, but will not survive the freezing process. A few sites theorize that 87% to 93% of the surface waters in the country are contaminated with Crypto, and 85% of all those tested have some level of Crypto in them.

History: It was first recognized in 1907, but extensive work on it has only progressed during the past 20 years. Crypto has become recognized as one of the most common causes of waterborne disease in humans in the US. The parasite is found in every region of the United States and throughout the world. The first documented major outbreak was in Texas in 1984 when 2006 people were infected through sewage contaminated well water and a failure to check the disinfection injection system. The most major incident happened in 1993 in Milwaukee when over 400,000 people became ill and more than 100 died after drinking lake water that had not been adequately treated. I have no idea as to the immunodeficiency of the fatalities, so I do not know the status of the deceased before the outbreak.


Giardia:

Cure: Giardiasis has a cure, but left unmedicated it can last for years with sporadic outbreaks.

Length of illness: Documented cases of the illness lasting up to 4 years have been recorded, with one over 30 years. Unlike Crypto, Giardiasis is not a disease that may be fatal, although if left untreated the victim may suffer for an extended period of time, seemingly getting better and then having relapses on occasion.

Infection rate: The runoff from rainfall can cause an increase in cysts in streams, rivers, lakes, and reservoirs. It has been reported that there is an increase in Giardia infections during and after heavy rainfall. One or two cysts are unlikely to cause an infection unless the individual’s immune system is severely compromised, as may be the case with the very young, the elderly, or AIDS sufferers. As with most infective agents there is usually a so-called “infective dose”, which depends on the physical condition of the person who is infected and the state of their immune system, so the size of the infective dose will vary.

Infection requirements: Cases have shown as few as 10 cysts can infect a person, but a group of 40 received a dose of 1,000,000 (yes, one million, I’d hate to be in that group!), with only 21 showing symptoms. The severity of the illness can vary considerably with host immunocompetence and only about a quarter of the people infected show symptoms of the illness, but can still infect others.

Symptoms: It has symptoms that are similar to food poisoning as well, to include acute diarrhea, which is often explosive (Ok, this should prompt people to rethink water treatment strategies!), abdominal cramps, bloating and excessive flatulence. The incubation period can be anything from 1 to 75 days with a median of 7 to 10 days. In an AWWA study, subjects who received 10 cysts found the median to be 9.1 days.

Survivability in the wild: Studies of the survival of Giardia cysts in the environment show they can survive for months in fresh water. Not all cysts are viable though, which means they are able to hatch and start the infectious cycle.

History: Giardia cysts are widely found in lakes and rivers especially where there is wildlife that uses these water sources. Concentrations as high as 240 per liter in surface waters were found, and there is evidence that cysts can also contaminate groundwater. Outbreaks are more common in the US, possibly because of more infected animals in the wilderness, which are popular areas for hiking and camping. In the period of 1971 to 1985 18% of all outbreaks of waterborne diseases were caused by Giardia, and it's speculated that number is much higher today.


As I mentioned before, I’m not trying to be an alarmist. The purpose here was to educate people on the possibilities of infection from waterborne diseases so they can make their own decisions on whether or not to treat the water. That’s not to say all sources are contaminated, as I’m sure they aren’t. These two organisms are the most concentrated upon because of their relatively new and increasing status, their debilitating characteristics, and their resistance to destruction. I have friends that choose not to filter, their rationale is that by the time they contract something, they’re at work anyway, so it doesn’t matter.

I always recommend people hike their own hike and this is no different. But, hopefully the information I have posted will shed some light on truths & myths, and provide a little information from which people can make their own educated decisions.

.

 

[Kevin Rooney]

Thanks for a superlative thread, Lawn Sale. A gem like this makes wading thru the usual stuff worth it.

 

[Jazzbo]

Thanks for the thread

Great thread Lawnsale! ... I agree with Kevin .... I'm going to try printing this one out. If I run low and need to obtain water on the trail and I don't have my filter I try to be selective and opt for the little seepy type springs just below tree line recieving from rocky mossy spruce areas with no trails passing by overhead. Even with the filter I try to be selective about picking my water source. The lower the source the more chance of getting poop byproducts. I like the MSR Miniworks for its ease of use as it screws to the top of a std liter water bottle and eliminates a juggling act of suspending multiple hoses on uneven terrain of rocky brooks. I'm going to take Lawnsale's advice and obtain Aqua Mira or other chem treatment.

 

[Greg]

Good info and good coverage, Lawnsale. It's always better to be safe, I think. Why court giardia if you don't need to.
Another class IV systems operator from the State O' Maine.

 

[jrichard]

I too think Lawn Sale's documentation is to be applauded.

I was speaking with someone who works in medical dialysis. She says that one of their patients ruined most of their kidney function as a result of drinking water from a stream during a honeymoon hiking trip. It's a second hand story, and there's no easy way for me to find out if it was a biological or chemical agent that caused the destruction, but it does make me pause when deciding if I want to use the aqua mira.

Although for me, it's not so much the mountain streams that I worry about, it's the chemical runoff into the lake and streams. I drink that stuff on canoe/kayak trips.

 

[Aviarome]

It sounds like that person had hemolytic uremic syndrome (HUS), which is often caused by a strain of E. coli. Obviously, E. coli is one of the important coliform bacteria that people worry about in contaminated water. Although, this is a very rare infection for backpackers drinking cleaner waters. It's more common to acquire this through contaminated foods and water heavily contaminated with feces.

Chemicals may also have caused the kidney problems, but it sounds like a case of HUS.

aviarome

 

[Quietman]

If I run low and need to obtain water on the trail and I don't have my filter I try to be selective and opt for the little seepy type springs just below tree line recieving from rocky mossy spruce areas with no trails passing by overhead.

This was my approach as well. Was hiking on Moosilaukee a couple of years ago with my 70 year old father, which required an overnight on the Benton trail about 2.5 miles in. Ran low on H2O but found a little seep spring far from the trail for a refill. Filled up the 1/2 gallon bag, started to walk back to our camp site and was temped to drink straight from the bag, but just 5 feet above the spring I stepped in a very large pile of moose droppings. I was very glad I had my filter in my pack back at the camp site. False security? Who knows. I know that having the filter was worth the weight and the cost.

Hadn't thought about it before but my miniworks filter is the most expensive piece of hiking gear that I have bought at $69.95. Even my ultralight 2 person EMS tent from the bargain basement was cheaper at $65(normally $199).

I had Giardia after drinking untreated water from a low elevation stream in my younger days. Not a fond memory!

 

[Wanderer1]

Lawnsale, very imformative article. I have a question on the washing of eating ware. Do these critters die once the water dries after washing? Does the soap kill them? Is it safe to wash your dishes with untreated water or can these things rehydrate and still harm you? I had ask this question a long time ago but never got an answer. I understand your cooking pots would be safe as they are subject to heat but I was thinking of eating utensiles and bowls.
Thanks