Backcountry Forum
Backpacking & Hiking Gear

Backcountry Forum
Our long-time Sponsor - the leading source for ultralite/lightweight outdoor gear
 
 
 

Amazon.com
Backpacking Forums
BackcountryGear.com
backcountry gear

---- Our Gear Store ----
The Lightweight Gear Store
 
 WINTER CAMPING 

Shelters
Bivy Bags
Sleeping Bags
Sleeping Pads
Snow Sports
Winter Kitchen

 SNOWSPORTS 

Snowshoes
Avalanche Gear
Skins
Hats, Gloves, & Gaiters
Accessories

 ULTRA-LIGHT 

Ultralight Backpacks
Ultralight Bivy Sacks
Ultralight Shelters
Ultralight Tarps
Ultralight Tents
Ultralight Raingear
Ultralight Stoves & Cookware
Ultralight Down Sleeping Bags
Ultralight Synthetic Sleep Bags
Ultralight Apparel


the Titanium Page
WM Extremelite Sleeping Bags

 CAMPING & HIKING 

Backpacks
Tents
Sleeping Bags
Hydration
Kitchen
Accessories

 CLIMBING 

Ropes & Cordage
Protection & Hardware
Carabiners & Quickdraws
Climbing Packs & Bags
Big Wall
Rescue & Industrial

 MEN'S APPAREL 

Jackets
Shirts
Baselayer
Headwear
Gloves
Accessories

 WOMEN'S APPAREL 

Jackets
Shirts
Baselayer
Headwear
Gloves
Accessories

 FOOTWEAR 

Men's Footwear
Women's Footwear

 CLEARANCE 

Backpacks
Mens Apparel
Womens Apparel
Climbing
Footwear
Accessories

 BRANDS 

Black Diamond
Granite Gear
La Sportiva
Osprey
Smartwool

 WAYS TO SHOP 

Sale
Clearance
Top Brands
All Brands

 Backpacking Equipment 

Shelters
BackPacks
Sleeping Bags
Water Treatment
Kitchen
Hydration
Climbing


 Backcountry Gear Clearance

Page 2 of 4 < 1 2 3 4 >
Topic Options
Rate This Topic
#165127 - 04/19/12 03:41 PM Re: Water purity overkill? [Re: sandia]
Rick_D Offline
member

Registered: 01/06/02
Posts: 2803
Loc: NorCal
Well that's a giant weight off my mind.

Hey everybody, watch for all my water treatment stuff over on the gear for sale forum.

Cheers,
_________________________
--Rick

Top
#165135 - 04/19/12 10:51 PM Re: Water purity overkill? [Re: Tye]
Trailrunner Offline
member

Registered: 01/05/02
Posts: 1835
Loc: Los Angeles
I tend to trust research more than anecdotal stories.
_________________________
If you only travel on sunny days you will never reach your destination.*

* May not apply at certain latitudes in Canada and elsewhere.

Top
#165148 - 04/20/12 12:47 AM Re: Water purity overkill? [Re: Trailrunner]
sandia Offline
member

Registered: 04/18/12
Posts: 68

Notion that technology can preserve health is correct, yet very widely misunderstood.

Wilderness water purification is prime example of this misunderstanding.

Parallel is with so-called nutritional supplements, a zillion-dollar retail industry.

These pills are ingested at astounding, alarming rate which is very profitable for their manufacturers and retailers.

Medical literature clearly suggests this stuff is at best useless, and frequently very harmful.

Anybody looking at relevant research, ought to doubt decades-old hysteria regarding drinking water




Top
#165150 - 04/20/12 08:47 AM Re: Water purity overkill? [Re: sandia]
Pika Online   content
member

Registered: 12/08/05
Posts: 1764
Loc: Rural Southeast Arizona
DELETED


Edited by Pika (04/20/12 10:21 AM)
_________________________
May I walk in beauty.

Top
#165156 - 04/20/12 12:23 PM Re: Water purity overkill? [Re: sandia]
BradMT Offline
member

Registered: 08/23/04
Posts: 148
Originally Posted By sandia

Anybody looking at relevant research, ought to doubt decades-old hysteria regarding drinking water





Yup.

Haven't ever treated backcountry water in Montana... ever.

But I have treated water elsewhere.

Yes, I've had Giardia (Missouri Farm Stream) and Hep-A (India) from water sources. Neither of those were what I'd call the backcountry, and neither were BP trips. Giardia is nothing compared with Hep A.

Truth is, both times I got sick I KNEW I shouldn't drink the water untreated. In India my treatment tabs got separated with my backpack in Kuwait and I got tired of drinking Campa Cola.

The backcountry water hysteria is silly in my view, but to each his own hike.

In over 37 years of backcountry travel I've never gotten sick from water, including a 1000 mile AT hike. Probably treated water twice on that walk. Doubt I've treated water more than 15-20 times in 37 years.
_________________________
There Is No Bad Weather, Just Bad Clothing...

Top
#165181 - 04/21/12 06:46 PM Re: Water purity overkill? [Re: BradMT]
Banjopickin Offline
member

Registered: 02/14/10
Posts: 58
Loc: NC
To each their own...If you feel safer treating water, then treat water. If not then dont. In my experience there are very few hard and fast rules when it comes to backpacking (LNT, food storage, etc. being the exceptions). Everyone has their own philosophy toward best practices. In my case I rarely treat water but here in the Southern Appalachian's there are more springs than you can shake a stick at so "good, clean" water is abundant. They key, like so many others have said, is source choice. Fresh mountain spring water is probably gonna be better than stinking cow pond water whether filtered, chemically treated, or nothing at all.
_________________________
Climb the Mountains and get their good tidings...
-John Muir

Top
#165189 - 04/22/12 01:29 AM Re: Water purity overkill? [Re: Banjopickin]
sandia Offline
member

Registered: 04/18/12
Posts: 68
An editorial a few years ago, in a peer-reviewed medical journal, argued that scientists should point out that, based on evidence, hand-washing, rather than filtering water, is best means to avoid gastro-intestinal complaints related to backcountry travel.

On the other hand, a certain, fairly high percentage of the total population, in a given year, will invariably suffer minor problems; mostly they are home in bed. A much smaller number will be overtaken, unfortunately, while camping.

Given incubation period of these "problems," most of these campers actually got the bug at home.

I'd rather be at home and get it from handling change at the local convenience store. But is basically like catching a head-cold. Stuff happens.

Some say taking many vitamins while regularly visiting your chiropractor or herbal enema specialist, can also help.

Top
#165192 - 04/22/12 06:52 PM Re: Water purity overkill? [Re: sandia]
BradMT Offline
member

Registered: 08/23/04
Posts: 148
Originally Posted By sandia
An editorial a few years ago, in a peer-reviewed medical journal, argued that scientists should point out that, based on evidence, hand-washing, rather than filtering water, is best means to avoid gastro-intestinal complaints related to backcountry travel.


I think this bears repeating, and is something I've read more than once.

The lack of personal hygiene in the backcountry often is the "culprit", not un-filtered water.
_________________________
There Is No Bad Weather, Just Bad Clothing...

Top
#165193 - 04/22/12 08:11 PM Re: Water purity overkill? [Re: BradMT]
lori Offline
member

Registered: 01/22/08
Posts: 2801
Members of the local swiftwater team have all been treated for giardia, some of them more than once. (you can't filter the river to make it safe to recover the kid...) They've pulled kayakers, boaters, swimmers, etc out of waterways all the way up to 8,000 feet.

Members of the SAR team have been treated once or twice over their careers as volunteer rescuers.

Still tabulating the members of my own hiking group who've had it. Apparently it occurs in dogs regularly enough that the vet recognized and treated one case in a group member's hiking pooch. I told one old fella who lives in the foothills and has a lifetime of hiking in the mountains that people think they don't need to filter or treat their water up there - he gave me the biggest WTF double take.

What do researchers do? Sample the water. Maybe a couple times? One pool in the river? Not enough to get a good idea of what's really going on. Show me a study that spans a good long time, repeatedly samples various locations on the river, throughout the year, and you might have something worthwhile. Some little study that doesn't do a thorough job ain't cutting it. Cause there's plenty of locals that think you all are nuts. Being sick isn't worth it.

You do your thing in the Central Sierra, don't say I didn't warn you....
_________________________
"In the beginner's mind there are many possibilities. In the expert's mind there are few." Shunryu Suzuki

http://hikeandbackpack.com

Top
#165194 - 04/22/12 09:16 PM Re: Water purity overkill? [Re: lori]
sandia Offline
member

Registered: 04/18/12
Posts: 68
There are nearly 100 million cases of intestinal infectious diseases annually in the United States, according to Garthright, Archer and Kvenberg, three researchers with
Food and Drug Administration's Center for Food Safety and Applied Nutrition, Washington, DC.

Is about a third of total population.

A third of the people I know who rode bicycles last year had intestinal infections during this period.

Therefore: bicycle-riding causes intestinal infections. I know this with utter certainty, because I've ridden a bicycle for many years!


p.s. I've never ridden a bicycle in Antarctica, nor, unlike my terribly obese aunt, paid for penguin cruise nor guides there etc. Perhaps gastro-intestinal complaints on these trips are also common due to high number of people riding bicycles.






Edited by sandia (04/22/12 11:23 PM)

Top
#165201 - 04/23/12 09:25 AM Re: Water purity overkill? [Re: sandia]
lori Offline
member

Registered: 01/22/08
Posts: 2801
These were all verified cases of ONE infectious disease. Giardia.

Get it straight.

Though it's possible hygiene had something to do with some cases, that's not the case with the swiftwater team, or with the SAR team. Swiftwater folks drive or fly to the scene, get in the water, and cannot help but ingest it - there is no backpacking or associated behavior involved. Same with my hiking group - we backpack 1% of the time, cases identified were veteran backpackers who reported histories of having at least one doctor or hospital visit and being diagnosed with giardia, many are reformed solo hikers who now understand that group hiking is safer or just want company on the trail. We warn each other.

Water treatment is mandatory now for all our SAR volunteers.
_________________________
"In the beginner's mind there are many possibilities. In the expert's mind there are few." Shunryu Suzuki

http://hikeandbackpack.com

Top
#165205 - 04/23/12 01:15 PM Re: Water purity overkill? [Re: lori]
Rick_D Offline
member

Registered: 01/06/02
Posts: 2803
Loc: NorCal
[redacted]

Back to water treatment--or not--it's risk management. Period. 1. Evaluate your risk. 2. Respond accordingly.

Nothing else to it. The humble among us will acknowledge that #1 is the tricky bit.

Cheers,


Edited by aimless (04/25/12 05:06 PM)
_________________________
--Rick

Top
#165207 - 04/23/12 01:25 PM Re: Water purity overkill? [Re: Rick_D]
sandia Offline
member

Registered: 04/18/12
Posts: 68
From the "old news" Rockwell article
Quote:
Ask the average outdoors person about Giardia lamblia or giardiasis, and they have certainly heard about it. Almost always, however, they are considerably misinformed about both the organism’s prevalence in wilderness water, and the seriousness of the disease if contracted.
With the advent of the Internet, the amount of information one can easily find on the subject is voluminous. Unfortunately, most of it is flawed in important aspects, being unsubstantiated, anecdotal, or merely quoting other unsubstantiated and anecdotal articles. Official sources, such as many informational publications put out by the US government, are not immune to this criticism.

This paper is the result of a critical distillation of relevant articles, retaining only those from scholarly, peer-reviewed, or otherwise professional and trustworthy sources.

One conclusion of this paper is that you can indeed contract giardiasis on visits to the Sierra Nevada, but it won’t be from the water. So drink freely and confidently: Proper personal hygiene is far more important in avoiding giardiasis than treating the water.

First, an excerpt written by a highly regarded wilderness physician:
“In recent years, frantic alarms about the perils of giardiasis have aroused exaggerated concern about this infestation. Government agencies, particularly the United States Park Service and the National Forest Service, have filtered hundreds of gallons of water from wilderness streams, found one or two organisms (far less than enough to be infective), and erected garish signs proclaiming the water ‘hazardous.”
And another, by researchers who surveyed the health departments in all 50 states and scanned the medical literature looking for evidence that giardiasis is a significant threat to outdoor folk:

Neither health department surveillance nor the medical literature supports the widely held perception that giardiasis is a significant risk to backpackers in the United States. In some respects, this situation resembles (the threat to beachgoers of a) shark attack: an extraordinarily rare event to which the public and press have seemingly devoted inappropriate attention.

Top
#165211 - 04/23/12 02:29 PM Re: Water purity overkill? [Re: sandia]
OregonMouse Online   content
member

Registered: 02/03/06
Posts: 6538
Loc: Gateway to Columbia Gorge
You really need to check the source and the date of what you read on the internet. There's an horrendous amount of material out there from spurious sources or which is outdated. This is particularly true of health related material! I personally prefer to rely on the Centers for Disease Control literature on water purity issues.

Sandia, your posts might be a little more believable if you'd list some specific reputable medical sources for your information! I'm certainly not hearing what you say from the medical sources I know and trust! I haven't seen a single scientific article listed in your posts, just "medical literature says...." What specific medical literature?

My concern here is sending beginners (who have no experience in evaluating their risk) out on the trail thinking they can safely drink any water without treatment!


Edited by OregonMouse (04/23/12 02:38 PM)
_________________________
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey

Top
#165212 - 04/23/12 02:37 PM Re: Water purity overkill? [Re: OregonMouse]
skcreidc Offline
member

Registered: 08/16/10
Posts: 1590
Loc: San Diego CA
sandia means this article here This is the oft cited article on the other side that I have seen.

I freely admit that I now usually treat my drinking water. However, I put on a couple of thousand miles with my family in the Sierra Nevada and Mt. Lassen from 1966 through 1979 without treatment generally speaking. If we had any doubt, we boiled the water. But this was rare in the Sierra and usually we just chose wisely. Giardia was around before I was born...so what was the difference between then and now? The amount of human traffic in the mountains is possibly the only major difference.



Edited by skcreidc (04/23/12 02:46 PM)

Top
#165213 - 04/23/12 03:00 PM Re: Water purity overkill? [Re: skcreidc]
OregonMouse Online   content
member

Registered: 02/03/06
Posts: 6538
Loc: Gateway to Columbia Gorge
The author of this article is a mountaineer. His degrees are in physics and aeronautical engineering, not biology, medicine or public health. This is not a scientific article published in a peer-reviewed journal and is therefore a suspect source!

I would like to check all his medical journal sources (note that over half the references in the article are not peer-reviewed scientific sources!) before recommending that anyone, especially a beginner, leave the filter or chemicals at home!

The author states that he has never gotten sick--that's fine. He's probably acquired immunity somewhere--he admits in his article that a lot of people don't get symptoms or get only mild ones. On the other hand, I've known several people with giardiasis (verified by lab tests) who were really careful with their hygiene and their water sources, and whose incubation period definitely dated to the few instances on their backpacking trips when they didn't treat their water, who have been miserable for months! I've never gotten sick either (and never treated my water until the late 1980's), but I presume I'm immune too. Unfortunately there are too many people out there not following proper sanitary procedures (unfortunately quite visibly evident in more popular areas!), and plenty of evidence that wildlife, as well as domestic livestock, can carry giardia.

Please remember that a lot of beginners who are not qualified to evaluate water sources read this forum! Plus, how much evaluating can you do without exploring a stream to its sources? I've seen several cases of dead animals in the creek a mile or two upstream!

There is enough scientific evidence of contamination problems out there that I would never advise a beginner not to treat his/her water. For those with more experience, go ahead and take the risk if you want. But please don't advise beginning backpackers that they shouldn't treat their water!

IMHO, we have a clear responsibility to the newcomers here!


Edited by OregonMouse (04/23/12 03:17 PM)
_________________________
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey

Top
#165214 - 04/23/12 03:18 PM Re: Water purity overkill? [Re: sandia]
aimless Online   content
Moderator

Registered: 02/05/03
Posts: 2956
Loc: Portland, OR
I don't think anyone in this thread has resorted to "frantic alarms about the perils of giardiasis" nor have they "aroused exaggerated concern about this infestation".

Whenever I see such highly colored language being used, it tells me that the author sees his position as adversarial, and it serves as a red flag, indicating that whatever information follows will be selected entirely on the basis of how well it substantiates the author's conclusions.

Giardiasis is not fatal. It is possible to be infected but asymptomatic. High concentrations of cysts may be very localized and infrequent. And statistically speaking, it is possible to drink untreated water from the High Sierra on a very regular basis for multiple decades and never suffer from it. All that is true.

It is also true that a nasty bout of giardiasis is extremely unpleasant and anyone who suffers through one bout of it will wish never to do so again as long as they live, whereas treatment is not especially difficult or expensive, and helps eliminate one's exposure to those infrequent high concentrations they might run across in a local water source.

Given both sides of the issue, choosing to treat is a perfectly rational choice, even without "frantic alarm" or "exaggerated concern." Not treating is also a perfectly acceptable choice, but it would be wrong to call it a choice that has no risk associated with it whatsoever, just as it would be wrong to raise "frantic alarms" over it.

Top
#165215 - 04/23/12 03:20 PM Re: Water purity overkill? [Re: aimless]
OregonMouse Online   content
member

Registered: 02/03/06
Posts: 6538
Loc: Gateway to Columbia Gorge
Or, as one physician told me, giardiasis won't kill you, it will just make you wish it did!

Excellent post, aimless!
awesome


Edited by OregonMouse (04/23/12 03:21 PM)
_________________________
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey

Top
#165221 - 04/23/12 04:03 PM Re: Water purity overkill? [Re: aimless]
Rick_D Offline
member

Registered: 01/06/02
Posts: 2803
Loc: NorCal
Good post, aimless.

Giardia has been known literally since the invention of the microscope by van Leeuwenhoek, in the 17th century. It wasn't recognized as a human pathogen until the 20th century. Today, it's still difficult and expensive to reliably diagnose, via one of these options:

-Enteroscopy
-Stool antigen test to check for Giardia
-Stool ova and parasites exam
-String test (rarely performed)

I don't know how definitive these tests are nor what the false positive rates might be. Some people respond badly to treatment, and doing so as a cautionary measure based on symptoms w/o diagnosis carries some risk.

Giardia is but one waterborne pathogen. There's crypto, which is more dangerous and not widely considered treatable. I'm more wary of bacteria than either cyst, myself, and then there are viruses. They aren't a widespread concern in North America but nevertheless, there have been outbreaks, such as norovirus in the Grand Canyon (the NPS has a report for anybody curious).

Water treatment tech has become so easy it's simply not much of a bother to take the extra step with any source you have even a sliver of doubt about. If the concern instead is you might be lining the pockets of unscrupulous, fear-mongering, parasitic marketeers, then use somebody else's. If the concern is recovering the several hours one might have expended treating water that didn't require treatment ("opportunity cost" from another thread!) then consider chemical or gravity systems that are hands-off.

What's not kosher, in my book, is counseling others to abandon accepted backcountry practices based on one's own belief system. Assume just one in fifty water sources is contaminated. Now tell me which one it is, so I can be sure to have treatment handy. See how that might not work?

Cheers,
_________________________
--Rick

Top
#165222 - 04/23/12 04:34 PM Re: Water purity overkill? [Re: Rick_D]
OregonMouse Online   content
member

Registered: 02/03/06
Posts: 6538
Loc: Gateway to Columbia Gorge
I'd also like to point out, as one of the "senior" generation, that the current backcountry practices of treating water didn't start until the late 1970's, when a lot of folk started getting giardiasis or similar illnesses after backcountry trips. Studies, especially by state fish and game departments, showed widespread giardia contamination in backcountry waters being spread by wildlife in the water (which most likely caught it from domestic animals or from humans not practicing proper sanitation). In other words, the idea of treating water didn't start out of the blue because some commercial outfits were exploiting the idea! In fact, filters for treating backcountry water didn't show up until several years after the above studies were first publicized. Back then it was a choice between iodine (which in my case resulted in a horrible allergic reaction!), chlorine bleach or boiling. It has since been proven that iodine and chlorine bleach (as opposed to chlorine dioxide) are not very effective in killing protozoan cysts.

The standard water test is only for coliform bacteria, but that started increasing in backcountry sources at the same time! The coliform bacteria count is an indicator of how much the water is polluted. They can make you sick, too!



Edited by OregonMouse (04/23/12 04:42 PM)
_________________________
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey

Top
#165223 - 04/23/12 05:28 PM Re: Water purity overkill? [Re: OregonMouse]
BZH Offline
member

Registered: 01/26/11
Posts: 902
Loc: Torrance, CA
Not trying to take a side one way or the other OregonMouse, but you did ask Sandia to provide proper references for his/her claim. Can you now back-up your claims with references?


Edited by BZH (04/23/12 05:28 PM)

Top
#165225 - 04/23/12 06:45 PM Re: Water purity overkill? [Re: BZH]
DTape Offline
member

Registered: 11/23/07
Posts: 661
Loc: Upstate NY
I am obviously not OM, but I emailed a professor at Paul Smith's college in the Adirondacks after reading his paper about water quality in the Adirondacks. His paper focused on the effects of acid rain. I asked if he has personally or knows of a study of Adirondack waters and biological contamination in regards to cysts, bacteria, etc... This expert was unaware of any study ever conducted regarding biological contamination of the Adirondack waters. However the DEC still recommends treating, assuming contamination without any evidence. The professor did say that the the results of a study would be fascinating to see if one would ever happen.
_________________________
http://ducttapeadk.blogspot.com

Top
#165228 - 04/23/12 08:52 PM Re: Water purity overkill? [Re: Rick_D]
lori Offline
member

Registered: 01/22/08
Posts: 2801
Originally Posted By Rick_D


What's not kosher, in my book, is counseling others to abandon accepted backcountry practices based on one's own belief system. Assume just one in fifty water sources is contaminated. Now tell me which one it is, so I can be sure to have treatment handy. See how that might not work?



Also, when the study tests one pool in one waterway, once, it doesn't paint a complete picture. These are organisms - they wax and wane, move, die off, grow again, propagate under certain conditions and disappear under others. The waterways are constantly fluctuating in flow, temperature, chemistry, etc. in tiny ways.... The system is changing all the time. To claim any waterway free and safe is ridiculous. It might be today. It might be tomorrow. No way to conclusively stake up a sign and say "drink! be healthy!"

I am posting to provide information - I don't care about theories and I'm sorry my information offends sandia, but one person's insistence that treating water is unnecessary just offends all sensibility. No person or entity can possibly expect to be correct on this point. The CDC, the park service, the forest service and the state parks will all tell you - it's not a guarantee that the water is clean. And they are correct. Sometimes they will tell you with certainty that it IS NOT clean, and DO NOT drink without treating. The water along the Ohlone Wilderness trail (cattle range! eeeew!) is all accompanied by signs next to each faucet to not drink it without treating it. Yosemite does not post a SAR person at the top of Nevada Falls on summer afternoons with a big ol' Katadyn filter and a five gallon bucket for no good reason - tourists who get there will dip their nalgenes and bottles into the Merced, which tested positive and is probably still positive, off and on, for e. coli. If you spend any time hiking upstream there, you'll see bunches of nekkid tourists in the water. Filter the water!

There is no way to predict what's upstream of you. No way to know who did what in the water minutes ago. No way to count the deer, llamas, goats, cows, horses and mules that marched through it with poop-covered hooves. You just don't know and until they make a very light and effective way to test it, you will NEVER know for sure what is in the water.

What do I know? That many of my fellow SAR folk treat it as an occupational hazard - you might get giardia. Shrug. Yeah, it's not life threatening, really. It's a darn nuisance. Me, I would much rather spend my sick time (same as vacation time for me) backpacking than suffering projectile evacuation from both ends and taking antibiotics that screw up my digestive tract further. (UGH.)

So, yes. I will tell you to treat the water in the central Sierra Nevada, absolutely. It would be potentially cruel to not say so - do I want my friends to go through this sort of thing? Not on your life. I like 'em. So I loan them my filter when they don't have one.
_________________________
"In the beginner's mind there are many possibilities. In the expert's mind there are few." Shunryu Suzuki

http://hikeandbackpack.com

Top
#165230 - 04/23/12 09:19 PM Re: Water purity overkill? [Re: DTape]
sandia Offline
member

Registered: 04/18/12
Posts: 68
Undue concern about safety of back country drinking water is traced to the Federal "Safe Drinking Water Act" of `1970s.

This law mandated that surface water used for public water supplies be filtered unless special exemptions were obtained.

Dutiful federal employees, naturally, obeyed their direct boss, and advised backpackers accordingly in national forests, BLM and NP properties, without regard to any known risk.

Rockwell, it is true, has Ph.D in physics. He admirably distilled a great deal of science for the lay reader, and cites something like 60 sources, many of them peer-reviewed articles in medical and public health journals.

If you can deal with statistical analysis and jargon, find direct links to many of these studies in the source list at end of Wikipedia article titled "Wilderness Diarrhea."

Among these scientists, Derlet is a particular authority on measurement and has been widely quoted in lay press. Zell, and also S.C. Welch and Timothy Welch (separate works by unaffilated authors) are worthy of attention. I also like TP Gardiner and D.R. Hill's joint work on the Long Trail in Vermont.

These are many of your basic scientific sources that are available beyond Ye Olde Woodsy Woodsman's sage advise.

Personally I filter main-stem, valley river water. In back country, I'd avoid livestock and seek tributary brooks, but filtering is, based on available evidence, "water purity overkill" and it clutters the backpack.

Top
#165231 - 04/23/12 09:38 PM Re: Water purity overkill? [Re: sandia]
Rick_D Offline
member

Registered: 01/06/02
Posts: 2803
Loc: NorCal
The SDWA covers water systems, not undeveloped open water sources, so looking to it for a rationale behind warnings to the public regarding the safety of drinking directly from lakes and rivers is going to be an empty pursuit. This is not a "big gummint overreach" to paraphrase certain of my inlaws.

The 1986 reauthorization did widen the SDWA's reach to include small and seasonal water systems not originally covered and has certainly led to the closure of a lot of small water systems. But that's a separate and unrelated topic.
_________________________
--Rick

Top
Page 2 of 4 < 1 2 3 4 >

Shout Box

Highest Quality Lightweight Down Sleeping Bags
 
Western Mountaineering Sleeping Bags
 
Lite Gear Talk - Featured Topics
Berghaus Mens Hyper Hydroshell jacket...
by Alf
08/03/18 06:36 PM
Anyone using a Gossmear Gear The one?
by toddfw2003
07/27/18 09:36 PM
Getting Accustomed to Zero Drop Shoes?
by Bill Kennedy
07/23/18 02:32 PM
Backcountry Discussion - Featured Topics
First trip with Bear Vault 500..not enough space!
by willie1280
08/17/18 08:10 AM
Wither Bergans of Norway?
by Steadman
08/14/18 09:09 AM
bad idea taking a newbie into the backcountry?
by toddfw2003
08/11/18 11:23 PM
Make Your Own Gear - Featured Topics
Featured Photos
Breakneck Ridge, New York
May 2012 Eclipse, Lassen Park
New Years Eve 2011
Trip Report with Photos
Seven Devils, Idaho
Oat Hill Mine Trail 2012
Dark Canyon - Utah
Who's Online
0 registered (), 47 Guests and 0 Spiders online.
Key: Admin, Global Mod, Mod
Newest Members
BrianR68, geckon, eaglesfan122, RedRobin, walkingnatur
12620 Registered Users
Forum Links
Disclaimer
Policies
Site Links
Backpacking.net
Lightweight Gear Store
Backpacking Book Store
Lightweight Zone
Hiking Essentials

Our long-time Sponsor, BackcountryGear.com - The leading source for ultralite/lightweight outdoor gear:

Backcountry Forum
 
 

Since 1996 - the Original Backcountry Forum
Copyright © The Lightweight Backpacker & BackcountryForum