Recently bio-nerd, fast guy, and friend of B&P Ethan Linck published an essay in Slate calling into question the empirical reasons behind blanket water filtration in the backcountry, writing: “The idea that most wilderness water sources are inherently unsafe is baseless dogma, unsupported by any epidemiological evidence.” Slightly more recently, clickbaiting mugwump hack Wes Siler published a rebuttal to Linck’s article in Outside, arguing that “The outdoor community made filtration a must for a reason.” As he has been for a number of years, Siler makes a compelling argument for how simple and intentional mis(re)statements can drive traffic while at the same time doing the broader argument a disservice.
Linck is clearly (the above quotation is the last sentence in the first paragraph) referring exclusively to wilderness or backcountry water sources, and a review of his citations (especially this one) shows that his thesis is quite air tight. Siler’s rebuttal, strongest when he contends that the evidence against water filtration is somewhat thin, relies largely on his, one has to assume intentional, conflation of what Linck has to say about backcountry water with frontcountry camping. I am happy to admit that one undergrad meta-analysis, which is 18 years old and drew on a small body of research, is not the most compelling source. But in the end Siler can’t argue against Lincks thesis without ceding his point at the same moment; if there isn’t much knowledge proving the safety of backcountry water, there can’t be much knowledge (beyond the anecdotal) proving its danger either.
The ideal solution would be a doctoral-level project collecting and analyzing a broad range of samples from a broad range of backcountry locations. Stating what agents were present and in what concentrations would be enough information for informed decisions, though speculation on where they might have come from would be welcome. Getting enough longitudinal data to make such an investigation statistically significant would make it a mammoth undertaking.
While I think ascribing malfeasance to folks like MSR is ridiculous, there can be little question that the folks who make and sell water treatment have little incentive to promulgate such research. Water treatment has been on the list of essential backcountry gear for at least 50 years. I can’t recall it not being mentioned in anything published during my lifetime. It isn’t a subject much mentioned in books written around the turn of the 19th century, and I haven’t read much outdoor literature which spans these two eras. I can’t recall for example of Colin Fletcher worried about water treatment much while hiking the Grand Canyon, but it’s been a while since I read A Man Who Walked Through Time. These would be a good historical masters thesis to accompany the above dissertation.
Anecdotally, I’ve had serious GI distress seemingly from unfiltered water only once, when I lazily and knowingly drank half a bottle of water straight from a cow trough before climbing up North Beaver Mesa during the Kokopelli Trail race 11 years ago, but those problems could have easily been from the massive stress I put on my gut during that 20 hour ride. Tests in two different clinics were both inconclusive. The effects were severe and highly unpleasant, but passed quickly enough. Since moving to Montana I’ve become exceedingly lax about treating water, and probably go 4-6 months without doing so on any of my personal trips. I’ve been more careful with M along, as she prefers as much, and with LB, as that seems the responsible thing to do. I’m much more rigorous outside the mountains, in placed like the Colorado Plateau and the Missouri River breaks. Long stagnant water or a river with lots of people and agriculture upstream seem like the right places to treat water, though I have no direct empirical evidence that this is best practice. When I encounter water like that pictured at top (the North Fork of the Flathead, which is used at its headwaters to benchmark water clarity) I find the notion of tasting it in anything other than it’s original form insulting.
In the end, Siler’s article moves me to name calling for much the same reason I’ve long wanted to push back against the urgency with which water treatment has always been depicted. Siler starts his article with a cautionary tale, to breed fear and thus caution, as well as doing what I did in the above paragraph, establish personal authority the cheap way. I was moved to recall the magazine ad ~20 years ( I think from MSR) which depicted a duck pooping midflight into a lake. The woods are unclean and disorganized, something which on the face of it is something to be managed with water filters and tents and sleeping pads, things which keep us “safe” by mimicking as close as possible the civilized environment which is our default. The more actively problematic, even pernicious, aspect of this dynamic is the extent to which we humans allow concern to be a substitute for thought. How we conduct ourselves in the woods has broader import, along with everything else we do, and the way in which water treatment for the backcountry is usually discussed does not reflect well on us* as a culture.
*And by us I mean richish pale people from the global North, for whom things like diptheria are an abstraction when they need to be considered at all.