Water Treatment

I use the sawyer inline filter as a gravity filter. It takes about 1.5 minutes to filter a liter of water. It is small and light (not as light as tablets, but…).

This is basically what I am talking about:

"In general, what's your favorite/lightweight way to purify your water?"

Chris, you really need to outline where it is that you will be traveling. There are some places where the water is already very clean. Other places, you want to get rid of Giardia. Other places, you might worry more about bacteria or viruses (like in Nepal). You really want to assess the risks where you will be, and then you can select the best method of minimizing those risks. Where the risks seem greatest, you may even want to use two methods. It also depends somewhat on your own body. Some people are very sensitive about water, and it really needs to be clean. Others of us have been drinking mountain water for a long time, and we just need to be moderately cautious.

Thirty years ago, I used iodine for water treatment. By twenty years ago, I was using various filters that had to be pumped. Now I use a gravity feed filter. It seems lightweight and cheap and effective and quick.

–B.G.–

I have owned:

Katadyn Hiker Pro
– Good Filter – Horribly Bulky – Not Quick to Clean
Steripen
– Requires Batteries – Can Be Finicky – No Way To Sterilize Bottle Threads/Mouthpiece – It's Electronic
Sawyer Squeeze
– Just as fast as a Steripen – No Moving Parts – Exceptionally Easy To Clean – You Must Sleep with it if near freezing weather is to occur (freezing will damage the filter) – Can be used as a gravity filter with the additional $5 tube adapters – Can drink straight from it

If you have any questions on any of these products, fire away.

Bob is spot on – treatment will vary by where you need to treat. I used the Steripen Adventurer Opti for all 2,181 miles for 5 months along the A.T , and when doing the New England trail used both my Steripen and then tried the Sawyer Squeeze Filter for a few days (which also worked great). Both have benefits and possible down-sides, just really a matter of preference. Gravity filters are also popular.

Sawyer Squeeze – 3 ounces – filter – but there are some peculiarites – look at other threads on this site

I've use Katadyn Pro which works okay, but it's heavy

I've used Steripen and have mixed feelings – I like the weight – I've used it reliably on a number of trips – but then on other trips it failed – I think it's just too complicated – if you use it, always carry an extra set of batteries

Some treatment systems are better for a group to use, and others are better for solo use.

I can think of some very expensive expedition-size filter systems that turned out to be very expensive piles of junk once the internal ceramic filter froze and then shattered.

–B.G.–

Sawyer says they haven't tested the Squeeze below freezing

They should test it because what good is a filter that can't tolerate freezing temperatures? About half my trips are below freezing at some point.

I will probably just shake out the water real good if it's going to be below freezing and ignore their warnings

Here is the best thing about the steripen, or a filter if you don't mind the weight… you don't have to wait long. That might not seem like a big deal, but in hot weather it's really nice to sterilize and gulp down a full liter or more of water and fill up again before you start hiking. To save weight or because you don't have enough storage capacity. With tabs you would have to wait or not be able to "camel up" on water.

Some people have noted that steripens are unreliable, so most carry backup tabs. I know that you can't sterilize the threads, but that's a really small amount of water. You probably end up with more exposure when you wash your face. Could be an issue though in bad water where you wouldn't even want to wash your face with it.
Also, gross/dirty water is still going to be nasty. If you have any chance of running into that kind of water with no other choice, then a filter it is.

Here's what I have learned from various posts on BPL. I took notes; hopefully I got it right.

Katadyn Vario Filter
15 oz
0 wait time
Use case: can be used when water source is small and not easy to get into a large container (i.e. you can't dip your water bottle into a small shallow source).

Platypus Gravity Filter
15 oz.
0 wait time
Use case: When water is plentiful (streams/lakes) and is easy to fill the dirty water bag. Best for in-camp use. Good for groups.

Steripen Opti
3.6 oz.
Wait time: 90 seconds per Liter. One liter at a time.
Use case: When the water is plentiful, clear, and it is easy to fill a container. Best for on-the-go filtering, when there are plenty of water sources and you don't want to carry a lot of water. Good for 1-2 people. Bring backup batteries and backup treatment.

Katadyn Micropur Tablets
Weight: whatever tablets weigh
Wait Time: 30 minutes for clear water to 4 hours for dirty water
Use Case: Good when water is clear and it's easy to fill up containers. Best when light weight is the most important water treatment criteria.

Aqua Mira Drops
Wait time: 15 minutes to 4 hours
Use Case: Good when water is clear and it's easy to fill up containers. Good for one or more people. Need to mix two solutions together.

Mike

Thank you very much for the insights
I'm mostly backpacking in Utah-lots of streams, lakes, etc
I imagine myself going to Montana,Wyoming, California-but pretty much western rockies type of backpacking

"brought some Katadyn water tablets-the light weight aspect was fantastic-the after taste and having to wait 4 hrs not so much (I've heard people say they've only waited 1/2 hour but I was paranoid)"

The 4 hour wait time is for cysts only. Viruses and bacteria will be killed in 15miutes. http://www.katadyn.com/usen/technical-support/micropur-support/chemical-water-treatment/

No filter will take care of viruses. However they will take care of cysts. The sawyer in line water filter can be connected directly to your water bladder It will filter as you drink and it has minimal effect on flow. You can drink as you hike through the bladder hose. If you are concerned about viruses put a Katadyn tablet in the bladder after you fill it. In 15 minutes the viruses and bactera are gone and then the in line filter will cysts as you drink. ^The filter weighs about 3 oz. Enough tables to last through the hike will probably only add less than a oz. Wait time is 15 minutes for the tablets and zero for the filter.

"Sawyer says they haven't tested the Squeeze below freezing"

No, Sawyer says you should replace it if it freezes. This is because water expands when it freezes. The expansion can damage the filter. In fact any filter with water in it could be dammaged by ice. You can avoid ice damage by draining the water from it before you go to sleep at night. For Sawyer you can drain the filter by sucking on the clean output side of the filter until no more water comes out. Or you can put the filter in your sleeping bag.

I use sawyer's in line filter, around 2 oz., with a ULA bag as a gravity feed/scoop into a platypus. I like this because the screw on aspect keeps the clean water from being polluted under most circumstances by the dirty reservoir above. I hike in the sierras mostly and on the nor cal coast. This has been a fine solution for me. I don't think I like tablets but will take a few if I think backup is required or a questionable source is likely.

Is it fair to say that Sawyer's inline version that would attach straight to your water bladder is better for just one person and that the squeeze would be better for group situations? Or does the inline go from dirty water bag to a new clean bag source?

I was reading about issues with the sawyer squeeze bags-that they might be prone to damage/holes-any experience with that? If you use a Platypus style bag will it thread properly to a sawyer filter?

You can set up the inline filter so that water goes from your bladder, through the filter to your mouth. Or you can use it as a gravity filter where dirty water in one bag goes through the filter to clean bag. Or You could stick the dirty end of the filter into a water source and suck out clean water from the clean side (no storage bages).

Which is better for one or a group or individual will depend on the individual or the individuals in a group. I don't own a sawyer squeeze but there have been a number of comments in other post on BPL about the squeeze bag failing. Also some posts about problems attaching a squeeze to platpus bags and others that have attached them. Apparently the threads are close but may not perfectly match. However apparently Everclear bags do thread on correctly.

Everclear is drinkable alcohol fuel! Evernew (a Japanese company) makes backpacking pots and pans and the water bladders we're discussing. I can understand the former name sticking in memory more than the latter! :-)

I had already switched to Evernew bottles a couple of years ago after losing I don't know how many Platypus caps. Evernew has the caps attached to the bottle with a plastic thong.

For the OP: You'll have to buy a membership to read them, but the series of articles by Roger Caffin, et al, "A Survey of Water Hazards and Water Treatment Methods," currently being published here on BPL, will answer all your questions!

AFAIK, no water filter will stand up to freezing unless it's fully dry (probably not possible under field conditions). That's why it's good to have a sleeping bag that is a trifle longer than you need! Filter goes in zippered plastic bag in the foot of the sleeping bag on freezing nights.

I understand the worry about freezing a filter, drying it as much as you can, and putting it in your sleeping bag. What I do not understand is why it won't freeze during the day. What do you do with it after using it during the day if the temperature is well below freezing?

(Disclaimer — I've never used a filter in freezing weather — just melted snow.)

If it's below freezing during the day, you use something other than a filter.

You might be able to put it into an insulated container or garment with a chemical hand warmer packet, but then you're relying on the insulation and packet for drinkable water, which is another potential point of error or failure.

Edit: Regarding the original post, I use:

1. nothing
2. Sawyer Squeeze filter above freezing if the water in the area is questionable
3. Steripen Opti below freezing (daytime) if the water in the area is questionable

From Sawyer website:

Q. Can the filter be frozen?
A. While we have no proof that freezing damages the filters we have no proof that it does not. Therefore we must recommend replacing the filter if you suspect it has been frozen.

If you shake it out real well then there'll still be a little water in the hollow tubes of the filter. So they'll enlarge a bit when frozen. Plastic will stretch.

I think I just won't worry about it.

Like someone said somewhere (and I've seen) when you melt snow, sometimes you can see little wriggly things in the water. I don't think you can assume melted snow ater doesn't need treating. Depends on snow.

Both sawyer and first need make filters that filter viruses. Most of use will never need that level of filtration, but it is a available.

"Both sawyer and first need make filters that filter viruses."

Sawyer already does:
http://www.sawyer.com/sawyersaves/products-pointtwo.html

Yes, that is what he said… BOTH SAWYER and FIRST NEED make filters that filter viruses,and indeed they do.

You should never trust a frozen filter if it uses hollow fiber technology like the Sawyer, Platypus or MSR HyperWorks, etc. If the tube is ruptured it no longer stops the baddies.

The Katadyn Hiker uses a paper filter element that is the best in sub-freezing temps. Many trips I have used one to filter melted snow (rather than bring it to a boil) for Dave and I. I pump it clear of water and keep it in a ZipLok in my bag at night, and just buried between my sleeping bag and extra clothes in the pack during the day.

Ha! My brain added the word "to"…"…and first need to make filters that". My bad. :O)

Again, thank you for all the info