Water Safety

I live and hike mostly in the Olympic Mountains. Sometimes I drink from streams that I know don't pass through commonly traveled areas. one of my friends commonly does that. We have never been sick from that. I carry coffee filters but if the water is crystal clear I don't even bother with them. I almost always is. Typically coffee filters are made up of filaments approximately 20 micrometres wide, which allow particles through that are less than approximately 10 to 15 micrometres. So it is far from perfect. What do you do? Boil, filter with a real filter? Drink directly from the stream if you know the source and feel safe about it? Ever been sick from drinking wilderness water?
I grew up decades ago hiking in the Cascade Mountains and no one ever considered ever filtering or boiling the water then. Maybe things have changed.

I drank directly from mountain streams for decades before I ever purchased or used a water filter. During that time I personally had one bout of illness I directly attributed to bad water, in Rocky Mt. National Park, when I was about 17 years old. It was a miserable experience, but I survived. My brother and his wife also fell prey to giardia once. They also survived, but it was not a happy experience either.

These days I will still drink directly from a mountain water source, even though I carry a water filter, but only when I can see that the water is emerging from a clear, cold and copious spring a short distance from where I collect the water. I regard filtering clear, fast running water to be mostly an overabundance of caution, but it isn't entirely a baseless superstition.

I'm with Aimless on this one. We filter our water in the Sierra unless it is right out of a spring. humans and animals upstream from where you are drinking can contaminate the water, and bacteria is a lot smaller than 20 microns.

I've had Giardia once, probably from a large river in the Sierra.

I filter almost all water (when I say filter I'm talking about using a Steripen) regardless of how clean it looks. I had amoebic dysentery once which pretty much scared me off from ever drinking untreated water. Granted it was in Saudi Arabia years ago, but the experience is something I don't ever want to have again.

I’ll drink straight from snowmelt and springs or seeps. But we boil most other sources. Some of the silty streams in canyon country will plug any filter almost immediately. The issue there is boiling might not be enough because of Cyanobacteria. The toxins are not removed by boiling and might be increased by rupturing the Cyanobacteria. So along our routes we look for springs and seeps and tend to carry more water than most folks do.

If you have the time, you can let silty water settle...or we strain it through a banana...to try to keep that filter working. Sometimes it does.

True and as you probably know collapsible buckets are sometimes carried for this purpose and folks relate “funny” stories about the buckets collapsing and loosing the water sometimes. But on the same idea stream we do look for small pools or potholes where the silt has settled somewhat.

The silt in canyon country can be so fine that it is very hard to clean it from a ceramic filter at all and usually plugs up after the first time very quickly.

With or without the peel? :-)

Just went back and reread this thread. To be honest, we've never tried filtering water through a banana.

But a bandana often works.

even "ground water" came from someplace. Only a microporous filter can remove giardia etc, besides filtering makes bad water taste cleaner. Boiling works but can still taste bad. Jim