Topic

Filtering glacial lakes water

Viewing 21 posts - 1 through 21 (of 21 total)
jimmy b BPL Member
PostedAug 4, 2015 at 11:19 am

Looking forward to a couple short trips in Glacier park in a bit and maybe just obsessing but how will the sawyer squeeze handle the "rock flower" mineral deposits found in glacial lakes up there. I really cant imagine this would be much of an issue but just checking. I normally don't run into much but clear water sources here. Sometimes a bit of tannin but mostly free of sediment.

Thanks, jimmyb

PostedAug 4, 2015 at 11:28 am

Lakes will probably be fine since a log of the sediment will have, well, settled; however I have found that glacial rivers will clog of that thing in no time. I had a bad experience a couple of years ago at Mt Rainier where my sawyer gravity filter clogged to a painfully slow trickle in a very very short time. Field back flushing did zero to improve it. I have stopped filtering from glacial streams / rivers and also carry a bit of aqua mira as backup.

David Chenault BPL Member
PostedAug 4, 2015 at 11:42 am

It's a very minor issue, and only really applies to a handful of lakes. Generally Glacier NP water is very good and very clear.

jimmy b BPL Member
PostedAug 4, 2015 at 12:03 pm

Thanks guys for such a quick response. I will try to stay away from filtering from flowing sources possibly containing sediment. I am now wondering if a few coffee filter would be worthwhile cheap insurance or would they be non effective. Also planned on Aquamira backup but I have stayed away from chemicals (edit: for normal use) with my kidney disease as I really never checked it out with the docs. Probably should soon.

thanks again jimmyb

Justin Miller BPL Member
PostedAug 4, 2015 at 12:41 pm

I was using an MSR Miniworks the last time I visited Glacier. Most of my filtering was done in flowing streams and was amazed at how clean the water was compared to the Appalachians or other areas in the east/midwest. I only cleaned the ceramic filter once over the course of two weeks. Something I often had to do every 2 or 3 days in the east to maintain good flow rate for 2 people.

Well I should say I wasn't amazed how clean Glacier was but how dirty back home is…

chris smead BPL Member
PostedAug 4, 2015 at 12:54 pm

I used the regular sawyer squeeze when I was in Alaska.
The glacial water looked like watery milk. I had to backflush every 4-5 liters or so….but it worked.

Jerry Adams BPL Member
PostedAug 4, 2015 at 1:31 pm

Sometimes you can find a sidestream that is clear even though the main stream has a lot of glacier silt

Sometimes you can let the water sit for a couple hours and let the silt settle. Just make sure you don't disturb the settled silt

PostedAug 4, 2015 at 4:12 pm

You can also prefilter with a 1 micron filter. The filters weight about 1.5 ounces once the metal ring is removed. But once wet they go up to about 5.5 oz. I'm currently experimenting with cutting most of it out and just using the bottom portion.

Filter

PostedMay 31, 2016 at 2:13 pm

Any further ideas here on how to pre-filter glacial water? Has anyone done the coffee cone/filter? How did that work? Just bring a large bottle and let the sediment settle and then filter from the bottle? Dig a small trench to a hole and divert some river water into it slowly to make a natural settling basin (a strategy for camp only due to the time involved…)? Other ideas?

David Thomas BPL Member
PostedMay 31, 2016 at 2:40 pm

“Sometimes you can let the water sit for a couple hours and let the silt settle.

“Other ideas?”

If you want the same settling action in a fraction of an hour, use alum (it’s in the spice section or sometimes next to the salt / baking soda but check the bulk spice section first – cheaper per ounce there).  A pinch in a few gallons is plenty.  Then, once settled, decant the clear water off the top VERY GENTLY.  Or use a short length of tubing to siphon the upper clear water to a lower basin.  If you’re rafting, just bring one or two 5-gallon buckets.  When backpacking with only small pots, you can line a hole in the ground with your tent or poncho or trash bag to make a several-gallon basin without carrying any additional gear.

Not only does the clarified water not clog your filter so fast, but chemical (AquaMira, Iodine) treatment is more reliable after clarification because chlorine/iodine can react with the sediments and not leave enough concentration x time for potentially infectious organisms.  And for UV treatment to work, the water has to be pretty clear.

+1 on looking for side streams.  In the Grand Canyon, where the Colorado River is very turbid, many side streams run clear.  In glacial areas, there will be some streams that originate in springs and seeps rather than from glacial melt water.  Also, lakes serve as sedimentation basins, so a lake’s outlet will typically be clearer than its inlet.  If taking water from a lake, go the leeshore (the upwind side) so there is less nearby wave action stirring up bottom sediments.

PostedMay 31, 2016 at 9:07 pm

I spoke with a hunting guide who worked in the Brooks Range and he said just drink the glacial water. :^) Glacial flour is a non-soluble fiber and aids in digestion. Typical Alaskan.

I’ll look for some alum. We will be hiking/packrafting from Lituya Bay to Yakutat (not my idea) and water along that stretch can be an issue at times due to the flat coastal plain and most of the larger rivers are glacial outwashes. It sounds like the incredibly fine nature of glacial silt keeps the stuff in suspension through Brownian motion (pedesis) and filtering with normal materials like cloth or paper is a waste of time.

No no real glaciers on Kodiak, so I’m not initiated.

David Thomas BPL Member
PostedMay 31, 2016 at 10:17 pm

Philip: Fred Meyers has Alum in the baking section if you’re provisioning in Anchorage.

From Wikipedia: “Between 30 and 40 ppm of alum for household wastewater, often more for industrial wastewater, is added to the water so that the negatively charged colloidal particles clump together into “flocs”, which then float to the top of the liquid, settle to the bottom of the liquid, or can be more easily filtered from the liquid, prior to further filtration and disinfection of the water.”

Since a liter of water weighs 1,000 grams, you’re looking to add >0.04 grams to it.  So one gram should treat 20 liters (5 gallons).  The weight of a penny (3 grams) should treat 60 liters.

If sourcing your own isn’t convenient, I can mail you some from Kenai.  Because it’s an “unknown white powder”, I wouldn’t put a return address on the envelope.

Arthur BPL Member
PostedJun 1, 2016 at 5:32 am

In the N Arizona area with some very high silt waters, i have used this combo.

10 liter folding water bucket Sea Summit.  1gram alum per 4 liters. Sit for about 20 minutes and water on top 3/4 of bucket is quite clear.  other option is to fill bucket and let sit overnight and it does the same thing. A small line from the handles up to a tree limb or similar helps to keep the bucket from tipping over. About 90 grams for the bucket

 

PostedJun 2, 2016 at 2:09 am

Safeway here in Kodiak had alum. I packed about 0.5 oz. and that should suffice for emergency water clarification. Thanks for the beta.

PostedJun 2, 2016 at 7:12 am

I’ve never filtered water here in MT, ever. I guess I just don’t get the obsession with filtering/treating water…

 

PostedJun 2, 2016 at 7:48 am

“I’ve never filtered water here in MT, ever. I guess I just don’t get the obsession with filtering/treating water…’

Continue that way and eventually you will get it…

Yes, most water will probably not make you sick. But a filter/treatment is an insurance policy against getting sick… all it takes in once an you will understand…

billy

PostedJun 2, 2016 at 12:37 pm

“Continue that way and eventually you will get it…

Yes, most water will probably not make you sick. But a filter/treatment is an insurance policy against getting sick… all it takes in once an you will understand…

billy”

 

How do you presume to know I haven’t had Hep A or Giardia?

In fact, I’ve had both. Hep A in India, Giardia after drinking from a midwest farm stream I absolutely knew not to drink from, but foolishly did.

Here in the mountains of Montana, after backpacking and living here for 24 years, I’ve never, ever needed to filter or treat water, and never have. On a 1,000 mile walk on the AT when I was 16 years old in 1977 I treated water no more than 3 or 4 times the entire trip when I wasn’t certain about the water quality. No harm no foul.

So, in other words, in 41 years of backpacking, and almost never having treated water from Georgia to Alaska, Maine to California, I’ve never been sick from a water borne source on a backpack trip.

HYOH…

Lawrence A BPL Member
PostedJun 2, 2016 at 3:41 pm

Nobody is saying you have to treat water, but a lot of Montana’s mountains are leased out to cattle ranchers. I’ve had lots of questionable water there that needed treatment.

PostedJun 2, 2016 at 5:01 pm

I rarely filter water here on Kodiak, but the mainland scares me a little.

Once in 25 years of drinking untreated water on Kodiak did I come down with bloody diarrhea. It cleared itself up in about a week. I’m guessing it was campylobacter or something (and I can’t say absolutely for sure it was from untreated water- it could have been food poisoning from town). It didn’t seem like such a big deal that I won’t drink untreated alpine water going forward.

David Thomas BPL Member
PostedJun 2, 2016 at 10:51 pm

It was refreshing, on multiple levels, to be told by NZ park rangers that (1) we didn’t need to treat the water, (2) they didn’t treat their own water, and (3) they didn’t recommend anyone treat their water.  It was one of those broadening experiences you get when you travel – maybe government employees don’t have to give the most ridiculously conservative recommendations at all times.

Between UV and iodine, I feel like I have fast (or light), convenient options.  But really – for a lot of my 20-30 mile trips – I’m back home at the end of the day/weekend and if I got a case of something, I could roll over in bed and ask a board-certified, internal-medicine physician for advice.  I’d fret more on an extended BPing or raft trip, but I may get more lax on extended day hikes and see what happens.

Viewing 21 posts - 1 through 21 (of 21 total)
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