I do the same as Wayne -- dip and drink. However, water treatment is a personal matter, and many will never drink without treating. That is certainly their option.
All the cases I have seen or read regarding intestinal trouble with hikers has been due mainly to tainted food, caused by improper storage. Things like summer sausage not refrigerated, allowed to warm in a backpack, etc. I recall coming upon a PCT hiker along the trail, dehydrated and nearly incapacitated due to his food poisoning.
Here are links from the "
Links to important Whitney information" thread in the Reference forum:
Water discussions (Drink untreated, or filter/treat/boil/etc.)
Water and Giardia around Mt. Whitney 60,000 Liters of Water Consumed -- Untreated Filter question (links to studies, etc.)
I used to filter the water, but reading the studies and the lack of finding anything that could possibly infect a person convinced me I do not need to treat the water.
Recent studies by a doctor (Robert Derlet) from UC Davis who has sampled water from lakes and streams throughout the Sierra have shown that the only places where the water is contaminated is caused by runoff from cattle grazing areas or stock corral operations. He also found that lake water is more pure than the streams, possibly due to UV from sunlight sterilizing the water in the lakes.
