Giardia: Let’s Talk SCIENCE

> Mountain water sources are the same as they were 50 years ago.
Extremely unlikely.
I suggest the number of uncivilised novices pooping near creeks and lakes, and the amount of cattle intrusion, have both increased.

Cheers

You are probably right about that Roger, but I was thinking more about water sources that are away from well beaten trails or off trail all together. I always treat water along trails that allow stock travel, no exception.

I do a lot of hiking in Big Sur and there is this place called Sykes Hot Springs that attracts 90% of the hikers in the area. After I heard a story about some old dirty hippie pooping directly into the big sur river (apparently he said something like "mother nature will clean me up man!") I always treat downstream from Sykes. But any of the side streams and creeks leading into the river are fair game for me.

To my knowledge, cattle intrusion has actually decreased in US wilderness areas over the past few decades (someone correct me if I'm wrong on that). There was a time when sheep herds ran around the high sierras decimating pristine meadows.

"Although humans are the main reservoir of the parasite, a variety of domestic and wild animals, such as dogs, cats, cattle, beavers and deer carry Giardia species and can infect humans."

YMMV

I understand the appeal of drinking straight from the source. I've done it myself.

Facts and personal risk assessment are two separate but related issues.

In my OP I cited one of Dr. Welch's papers. (Almost all roads in the "giardia myth" science lead back to Rockwell, Welch and Derlet, with Derlet being by far the most scientific.) There is no evidence that wilderness waters in the United States…are unsafe for consumption. Thomas R. Welch, MD. (Source: Adirondack Explorer, May/June 2009.) I am not trying to impose choices, but I am arguing against demonstrably false statements like Welch's because they are the "facts" upon which many people base their choices.

Public health agencies are unanimous on the topic, or nearly so: there is significant risk in drinking untreated backcountry water, although the exact degree of risk is clearly unknown.

Treating is a personal choice. No one should allow themselves to become severely dehydrated if they run out of water and any reasonable looking source is available.

After researching the facts at length, my personal choice is to treat nearly all surface water. Others may do as they wish.

That said, I stand by the facts I've presented until proven wrong by documented evidence to the contrary.

"my personal choice is to treat nearly all surface water"

Exactly. I treat nearly all water. The possible exception is if I can see water dripping off a snow bank and I can't see the paw tracks of grubby little mammals.

–B.G.–