Filtering Silty Water

I hiked Paria Canyon years back.  I took a couple of empty milk jugs with me as a hard sided container to let the water settle.  I was able to use about 2/3 of the settle water.  Bulky, but light; I just strapped them to the outside of my pack.  my 2 cents

This worked for me –

https://backpackinglight.com/forums/topic/98322/#post-2159480

. FILTERING THE COLORADO .

Just ran across this a while back, a newish product called Water Wizard for River Runners that seems really good.

The video is a bit too long but full of info.

Unlike rafters (who pack beach chairs and 200-quart ice chests), you have a desire to keep your weight low.  And yet relying on the Colorado for water will save you many pound-miles of hauling water.  So while for rafters, I’d advocate a fair bit of gear (belt & suspenders), as a UL hiker, I’d say 1) lots of UL containers – at least twice, better yet, three times the volume of water you hope to settle and treat, 2) a very small pinch of alum for each container of river water to be settled, 3) UV for treating the settled water and 4) chemical – iodine or chlorine – as backup treatment.

If you have the volume, sturdier than Jon’s gallon HDPE milk jugs are the 1-gallon HDPE container that windshield wiper fluid comes in.  I’d cock it at 30 degrees off vertical Wilhelm settling to get the sediment down in one corner of it, avoiding the sediment sliding to one corner so much when you start to pour from it.

Anytime there is agricultural run-off, I want a carbon filter in the purification system. I used this one at Paria: https://www.rei.com/product/830746/katadyn-hiker-microfilter. We did ok on the 5 night 3 person trip with just one filter, but it’s smart to bring a replacement cartridge just in case.

Like others, I found it essential to have lots of extra plastic water bags to let most of the silt/clay settle out. You can destroy a filter pretty quick if you just pump out of the river. The Platypus are great. The 2 liter Sawyers are way cheaper (Zpacks), but the caps leak; still good enough for settling. I found an hour settling before pumping to be ok.

I try to restrict my aluminum intake, so after seeing the alum dissolve in water I decided I didn’t need it. Turned out to be right.

BTW the Katadyn went back to Paria a couple years later, and worked well again.

The 2-liter platypus bottles are ideal for this purpose, for 3 reasons:

(1) They are very light (about 1.5oz) for the volume they hold.
(2) They are small enough that you can shake them thoroughly to ensure that the alum has dissolved thoroughly, which is critical – much more effective than stirring in a bucket.
(3) They have a tall/thin aspect ratio that makes it easy to decant off the clean water when the sediment has settled to the bottom.

Alum is ideal for this purpose, there is no reason to consider a filter.  You need a very tiny pinch for two liters, shake the bottle thoroughly to ensure that it has dissolved, and you can turn mud into crystal clear water in 30 minutes.

Alum in the tiny amounts involved here is not at all harmful:  it’s a baking and picking ingredient, that’s where you find it in grocery stores.   And bear in mind that in the Grand Canyon there will only be heavy sediment that requires it less than 5% of the time;  and that if you have no time constraint, you can just often just leave it overnight without the alum to settle.

I try to restrict my aluminum intake, so after seeing the alum dissolve in water I decided I didn’t need it. Turned out to be right.

You don’t need it except on the rare occasions when you do need it.   In which case, on the Escalante Route in the GC, you are shit out of luck for a potable water supply.

If the alum doesn’t dissolve, it won’t work.  The whole point of alum as a flocculating agent is that the aluminum ions in solution have a high charge density.   But you need only an unbelievably small amount, and some of that precipitates out with the flocculating sediment.   I think your health concerns are unfounded, and ensuring a potable water supply is vastly more important.  This can be done with minimal weight penalty – a few ounces for some collapsible platypus bottles, and the amount of alum you need will likely not register on your scale.  It’s kit that’s always in my pack in the Grand Canyon, even though I have needed it only a couple of times in hundreds of nights below the rim.

And again, I can’t emphasize strongly enough – after adding the alum, shake the bottle very thoroughly to ensure that the alum dissolves and that the sediment is mixed thoroughly with water containing the aluminum ions.   This seems a bit counterintuitive to some people, because you ultimately want the sediment to settle to the bottom.  But you can think of it intuitively as the dissolved aluminum ions “coating” the small sediment particles, which allows them to stick together to make bigger heavier particles that settle out faster.

I’m an advocate of using alum, but if you don’t want to, more time works, too.  But it may be a few hours instead of 20-30 minutes.  That’s fine for where you’re camped overnight (if you have enough containers).

Also, research the clear-water side streams in the area of your hike.  The rafters try to fill up their containers there and skip all the flocculation, settling and decanting steps.  If your hiking guide doesn’t address those location, look at the rafting guide books – they certainly do.

There are no side streams on the Escalante Route until you reach Hance Creek.

This forum amazes me as to the depth of knowledge shared here.

Thanks all for the thoughtful responses.

I think Ill go with the alum and the CNOC/Platypus containers then the Sawyer and a drop of aquamira.   I picked up some Alum at the grocery store and played with a bucket of dirty water over the weekend.   That stuff works!

John, just a warning, there seem to be some people going up the little Papago climb in the wrong place, around to the right in a spot that’s pretty much vertical, and then foolishly posting videos of themselves doing this to youtube.

This is the WRONG place, around to the right side.   I mean, it’s still not difficult, but it’s unnecessary exposure to a nasty fall.

And these guys probably watched the video above and are also going up the WRONG place and posted their video:

This young lady is closer, but still too far right.  I mean, you can see looking at the video that there are much easier big ledges to her left.  She eventually does come back left.

Here’s the RIGHT place, you can see how easy it really is.

I guess this is the modern media version of people getting off route and foolishly putting cairns there, so that a bunch of other people all start going the wrong way too.  Don’t put cairns and don’t post videos unless you are familiar with a route!

I think Ill go with the alum and the CNOC/Platypus containers then the Sawyer and a drop of aquamira.

Bear in mind that although there is rarely enough sediment in the river that you actually need to use the alum technique, there’s often enough that it may eventually build up to clog a filter.   So I tend to favor non-filter purification methods.   I routinely drink river water without purifying it at all, it’s extremely cold and the volume of water is so massive that I don’t think bacterial or viral contamination is of any concern.   Side stream water I’d always purify, of course, especially where there are other humans around.   At Hance Creek, you can get water just above the trail crossing right where the spring comes out of the ground.

Keep in mind that if you are going to take the time to let the sediments settle out, chemical treatmentment is proably one of the better options.  Both take time anyway and filter can get easily clogged.

If you are going to rely on a filter, I would take one that can be cleaned in the field.  For trips with a lot of sediment, I take my MSR MiniWorks, I would not take a Sawyer.  My 2 cents.

Settle / alum first, then decant, then add chemicals to clear water (if you choose to use chemicals).

You don’t want chemicals binding to random gunk in the sludge instead of killing bacteria.

— Rex

Wow.  Thanks Ralph!