Straight from the Source A hiker gulps from a creek in the . Photo by Eric Winford ARE THE RISKS OF SWILLING SIERRA WATER OVERBLOWN? By Eric Winford

I’m alone in the Desolation with and my health with a nasty bout of intestinal Coliforms are present in the intestines of pose the greatest risk to Sierra backcountry water rushing around me. Draining from a warfare. every animal. While not every coliform hikers. You should not drink water from gleaming snowfi eld and veining together is harmful to humans, they serve as an such sources without treating it fi rst. into creeks, the water fi nally fl ows into Fortunately, my risk assessment analysis indicator of fecal contamination in water. glacier-cut lakes. But instead of enjoying has been made clearer due to the research of Just because a high country lake is the experience, my mind is occupied with Robert Derlet, a professor at the UC Davis Fourteen of 31 sites Derlet studied had emerging from a spring thaw does not an internal debate: Should I drink this water School of Emergency Medicine. evidence of coliform bacteria. These sites necessarily make it any safer. Depending straight or purify it? were below areas where cattle grazed, on available nutrients, the ph of the water Derlet has conducted several studies to close to sites used by pack animals or had and temperature, E-coli can survive years Drinking water straight out of a stream look at the presence of E-coli and other signifi cant human use. Another study done in cold water and can live an undetermined or lake appeals to the ancestral human bacteria in hundreds of water sources up in Yosemite, Kings Canyon and Sequoia amount of time in freezing water. “Many within me. It just feels good to cup my and down the Sierra. A survey of lakes and national parks showed that of samples people think that freezing kills germs, but hands and sip the waters of the earth. I feel streams ranging in elevation from 6,500 to taken from 15 sites in areas heavily used by this is not true,” Derlet says. more refreshed and energized with water 11,100 feet in six wilderness areas, from humans and 15 sites rarely used by humans, taken straight from a stream, almost as the Wilderness in the south only one instance of coliform was found in Giardia lamblia is another nasty microbe if by purifying the water I remove some to the near Tahoe, each. That study also showed that all the that backcountry travelers have been warned essential quality. Besides, I desperately found that more than half had no evidence areas where cattle grazed and 80 percent about for decades. But, according to Derlet, want to believe that there are still places in of contamination. of the areas that had pack animals were the threat of Giardia has been greatly this country that haven’t been tainted by the contaminated. exaggerated. heavy hand of humanity, places that aren’t Coliform is an umbrella term for several yet fouled by E-coli bacteria and Giardia. species of bacteria, such as E-coli, Thus, Derlet concludes, water in lakes and There are six different species of Giardia, Salmonella and Campylobacter, which streams below where cattle may graze or two of which cause harm in humans. But I also don’t want to sabotage my trip can potentially cause harm in humans. where there is evidence of pack animals Giardia is brought into the backcountry by

12 ASJ—July/August 2006 the same methods as E-coli: by cattle, pack after a thundershower,” Derlet says. Mid- animals and humans. Wild animals, such as summer is probably the safest bet. beavers and coyotes, can carry the microbe, but it is not known if the type wild animals In the high alpine regions of the Sierra, carry is the same species that can cause Derlet says you can be reasonably assured harm in humans. Dogs can also be a carrier that the water is safe to drink if no cows, of E-coli and Giardia. horses or pack animals have traversed the area, and it’s not a popularly visited area Yet several studies have shown that the where backcountry lavatory etiquette is levels of Giardia present in Sierra lakes suspect. and streams are too low to cause illness. Studies of backpackers who have developed Good hygienic and food preparation diarrhea and other symptoms have rarely practices can also greatly reduce the shown Giardia to be the cause. Rather, possibility of sickness. Washing hands researchers believe “traveler’s diarrhea” is frequently or using a water-free hand more likely the result of careless personal sanitizer, especially if a dog is in the camp, hygiene and food preparation. may be more important than treating water.

Overall, the risk of contracting a stomach Indeed, how we camp when we’re in the bug is low, if areas where cattle and pack backcountry has a big impact on the quality animals graze are avoided. But to entirely of water in the Sierra. Derlet’s research has remove the chance of slurping up some shown that most waters are in fairly good coliform, one needs to fi lter or treat the shape, thanks largely to improved camping water. That’s the only 100 percent way to practices. “The lectures given when

If you’re searching for the safest water, don’t go deep. The fi rst foot of a lake’s surface generally has the fewest microorganisms be- cause the UV rays from sunlight are profi cient germ killers, while heavy microbes, like Giardia, tend to settle to the bottom. be sure. Should you choose to take the risk, backpackers pick up their permits have you can reduce your potential exposure by made for a much better watershed,” he says. being aware of where you’re and taking certain precautions. Despite how enticing it is to camp right at the water’s edge, camps should be placed No matter what precautions you take, at least 100 feet from water sources. If you’ll be ingesting bacteria of some type you decide to go for a swim, rinse off or another. There is no body of water in the any sunscreen or bug repellant before Sierra totally absent of organisms. There are you enter the water. Don’t bathe in lakes an estimated 10,000-20,000 bacteria present and don’t wash your dishes in the lakes; in a liter of water from the Sierra, according even biodegradable soaps may contain to Derlet. These normal aquatic bacteria phosphates that induce excess algae growth. are not harmful to humans. They form the Finally, when the potty bell rings, answer basis of the food chain and are necessary to the call far away from creeks and lakes, sustain higher forms of life from frogs to farther than you think necessary, at least 300 fi sh. feet.

If you’re searching for the safest Swilling pure, cold mountain water is one water, don’t go deep. The fi rst foot of a of life’s simple pleasures. We can all help lake’s surface generally has the fewest to preserve this refreshing, life-sustaining microorganisms because the UV rays from practice for all who venture into the Take sunlight are profi cient germ killers, while mountains after us. heavy microbes, like Giardia, tend to settle Advantage to the bottom. Contamination levels also Eric Winford is a seasonal ranger in the fl uctuate with the season. “(Water is) more Desolation Wilderness (Eldorado National of 50% off polluted during spring runoff, as everything Forest) and freelance writer based in South in the soil is washed into the streams, like . Kayak rentals on Fridays.

Kayaks are welcome to launch from the visitor’s center and the launch ramp.

For fishing conditions and information go to: www.NorCalFishing.com

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