High Sierra Topix

I've read that it is not necessary to first filter the water intended to be boiled for rehydrating a meal or hot coffee? Do you agree?

I will have a filter anyway, for drinking water...

The process of boiling kills anything nasty in the water. No need to filter first.

Wikipedia: "Boiling for water sterilization"
"Boiling can be used as a method of water disinfection but is only advocated as an
emergency water treatment method, or as a method of portable water purification
in rural or wilderness settings without access to a potable water infrastructure.
Bringing water to the boil is effective in killing or inactivating most bacteria, viruses
and pathogens. Boiling is the most certain way of killing all microorganisms. According
to the Wilderness Medical Society[citation needed], water temperatures above 160 F
(70° C) kill all pathogens within 30 minutes and above 185° F (85° C) within a few minutes.
So in the time it takes for the water to reach the boiling point (212° F or 100° C) from
160° F (70° C), all pathogens will be killed, even at high altitude. To be extra safe, let the
water boil rapidly for one minute, especially at higher altitudes since water boils at a lower temperature."

When I collect water for boiling, I pour it through a zip loc baggie with a corner cut out and a handiwipe inserted in the baggie to act as a physical filter for sediment. Boiling does the disinfecting, but it won't remove the floatsam that often gets suspended into the collected water, even if collected from below the surface film.

There is quite a bit a research, I believe some on this website, that shows that filtering or boiling Sierra water is not necessary. I filter more for sediment than for sanitation and rarely filter drinking water along the trail. Bob Blakwell (Mr. Whitney) published an article 5+ years ago on this subject and Backpacker Magizine had an article around the same time (but waffled on their recommendation).

I never filter water.

Mike

I always filter drinking water. Giardia was bad enough once, I don't want to repeat the experience.

Mike M. wrote:I never filter water. Mike

Same here, mostly. There are places, highly impacted by people and stock, where I always bring a filter along. Mostly, clear water above 5000 feet with its origins somewhere above not impacted by people/stock is OK to drink and is far better than tap water. This has worked for me for over 20 years when I stopped automatically bringing a water filter. Be choosy about your sources.

Carne_DelMuerto wrote:I always filter drinking water. Giardia was bad enough once, I don't want to repeat the experience.

Me too...been there done that one time & it was enough to make me always filter my water.

Water Treatment in the Backcountry: http://www.highsierratopix.com/411_water_treatment.html" onclick="window.open(this.href);return false;