Advice on water filter systems

[Nomad]

What's the deal with cross-contamination with filters? I just got a sawyer mini and have been thinking of making a little pouch to keep all the bits together, bit it seems to me that the squeeze pouch and straw/tube will get wet with unfiltered water, which could transfer to the syringe or the clean side of the filter. Is it okay to shake off the dirty water, such that there are insufficient remaining nasties to worry about? In other words, are the nasties an issue when you're drinking the unfiltered water, but not when a drop (or less) gets onto the clean side of the system - or is it important to be fastidious about keeping them separate or cleaning off the dirty-side bits after use?

 

[Goatboy]

Nomad, I was taught and taught others always to avoid cross contaminating stuff, came from working with nasty chemicals for a while.
I always kept the bits of my filters in different pouches as yes you can recontaminate the clean parts. Silimarly I've seen folk get sick when using treatment tabs by sterilising the water in the bottle they scooped it from the dirty source from. The water inside was safe but there was untreated water on the lip and threads of the bottle.
If you can as well try to leave the parts out to dry if its sunny as when dried and exposed to UV it's less likely to harbour something to make you ill.

Sent via smoke-signal from a woodland in Scotland.

 

[Bluffer]

It's basic hygiene really.

Keep your clean stuff clean - water, food, etc.

Keep anything wet or dirty separate.

I've never understood the obsession with cooksets where the burner is stored inside the pot. Far better to keep the burner in a separate pouch and use the pot to store food?

I was working yesterday, advising a group going to Borneo, the main point of my lecture was that the next few weeks will be a test of their personal logistics and skills, this sort of thing takes on a life of it's own when in the bush.

 

[Quixoticgeek]

The general advice I've seen is that if you are using chemical treatment in a bottle, turn the bottle upside down, loosen the cap half a turn so some water runs out, this should clean the threads area of the bottle.

I store my sawyer in the outside pocket of my pack, the straw goes in there along with the pouches. But, most importantly, I keep the cap on the clean side.

J

 

[Bluffer]

The general advice I've seen is that if you are using chemical treatment in a bottle, turn the bottle upside down, loosen the cap half a turn so some water runs out, this should clean the threads area of the bottle.

This would be inadequate in most of the world where the real nasty bugs live.

It's an attempt at hygiene that would work some of the time, but there are no shortcuts with hygiene.

One or two bugs on their own can cause illness.

All of the bottle filters will become mouldy and manky inside; and there is no safety margin when you drink straight from the bottle, there is no 'contact period' to allow disinfection of any bugs migrating through the device.

Much of the advice in lonely planet type books is for people in hotels and hostels, with a dodgy but partially treated water source.

In terms of water hygiene, it is vital to filter AND disinfect effectively.

Always have more than one means of water treatment, even more important when you don't know what your source will be.

 

[K813ZRA]

My advice is always use chemicals or boil, as contaminating water isn't particularly difficult, and just a little juice from something rotting I'd enough to ruin your time. As for the water to go it seems pretty handy as it attemts to remove all the chemicals and sediments. Remember that in Spain you can't drink the tap water purely because you are not used to the minerals there in!

I have been drinking the tap water here in Spain for about 3 years and have never had an issue. I had no issues in Portugal either.

 

[sunndog]

This would be inadequate in most of the world where the real nasty bugs live.

It's an attempt at hygiene that would work some of the time, but there are no shortcuts with hygiene.

One or two bugs on their own can cause illness.

All of the bottle filters will become mouldy and manky inside; and there is no safety margin when you drink straight from the bottle, there is no 'contact period' to allow disinfection of any bugs migrating through the device.

Much of the advice in lonely planet type books is for people in hotels and hostels, with a dodgy but partially treated water source.

In terms of water hygiene, it is vital to filter AND disinfect effectively.

Always have more than one means of water treatment, even more important when you don't know what your source will be.

+1 to all that
really not keen on those bottle filters or survival straw type things for anything but water that fairly clean/safe to start with (i like my clean water containers CLEAN)
Using one of those in say rural india for example is asking for trouble imo

Always use two different means of treatment....filter and disinfect, but if in doubt go for a third and stick some more chemicals in there

 

[Quixoticgeek]

On a related note, I filter water from the Sawyer water pouch into my evernew water pouch. I like the idea of sticking a Chlorine dioxide tablet in to the mix to give a belt and braces setup.

Would you put the Chlorine Dioxide tablet into the dirty pouch, or the clean pouch?

I am pondering adding an activated carbon stage to the sawyer setup, would you use that as a pre filter, or a post filter? Does this change the answer to the question about where to put the Chlorine tab?

Cheers

J

 

[sunndog]

How would you add the charcoal element to the sawer?

For me it would be charcoal, sawer, into clean bag, then the chlorine

 

[Bluffer]

As sunndog states - filter first, disinfect last.

It has to be that way around or else the chlorine is 'deviated' by the particulates in the unfiltered source water.

The best devices incorporate different grades of pre-filters and filters, then the carbon polish.

Bear in mind that your 'disinfect' bottle should ideally be one-litre (or multiples of one-litre, two-litre, three-litre, etc) because the tablets are designed to dose one-litre.

The best devices, in my opinion, are Katadyn and Lifesaver.

After a few months continuous use, disassemble your filter and inspect the insides, they will be mouldy and manky; and some are not designed to be cleaned (the Lifesaver membranes will be damaged by bleach/Milton, becoming dry or being frozen).

As ever, the simple designs are the best.

 

[Bluffer]

The survival-straw type filters look like a great idea and can be slipped into a pouch or pocket.

Great.

But you have lie flat on the ground and suck like crazy every time you need water.

Even then, you only get a mouthful and you'd have to spit that into your kettle or bottle.

I'm surprised that they have ever sold any, ever, to anybody?

 

[Goatboy]

They are aimed at the "survival" end of the market or in places where water will be really marginal. I.E. Where there's only.a little trickle and scooping up quantities would be out of the question.
Also their small packable nature means they can be slipped in a pocket/pouch and forgotten about 'till needed.
Personally I prefer something that can handle more volume.

Sent via smoke-signal from a woodland in Scotland.

 

[homesicksteve]

...you have lie flat on the ground and suck like crazy every time you need water.

Even then, you only get a mouthful and you'd have to spit that into your kettle or bottle.

I'm surprised that they have ever sold any, ever, to anybody?

A container can be used to drink from.

This guy here demonstrates :

https://www.youtube.com/watch?v=2lpnWrqQ788

 

[Bluffer]

Which proves that the only people using technology to make drinking water from sewage is

A. Astronauts.

B. Attention-seeking fools.

 

[Jared]

Came across this today off another forum...

http://www.aquamira.com/products/frontier-max-filtration-system/

Looks as though can be used as an inline or gravity filter.

In normal use it claims it'd get rid of significant amount of nasties making chem or boiling more effective.

Think it's relatively new, as reviews are thin on the ground.

 

[homesicksteve]

Which proves that the only people using technology to make drinking water from sewage is

A. Astronauts.

B. Attention-seeking fools.

...and that you don't have to "lie flat on the ground & suck like crazy" QED

 

[mikedefieslife]

Well a few weeks on and I'm actually getting on well with the Water2go bottle. Must have gotten used to it.

I haven't used it on known bad water with deadly parasites and the like yet though.

On a separate note, I guess bathing and washing clothes in lakes and rivers (using environmental soap) is a no no due to parasites, rat urine, bacteria etc..

 

[dragon32]

Hi Guys,
On the same subject but a different angle, has anyone tried a substance called "Poly-glu" from Japan. I saw a program on NHK world that appeared to show this stuff (which is made from soya) clearing water from a river in Bangladesh. It took twenty minutes to clear and remove chemicals, bacteria etc, and the people who tried the result said the water tasted like mineral water. Would love to know if anyone has tried it. I may try to get some from Japan myself to try.

Don

 

[PDA1]

Note that Sawyer have two standards. 1 the .1 filter removes all biologicals except viruses, 2 "point zero two" also removes viruses. 2 is more expensive and filters more slowly than 1. As others have pointed out, beware cross contamination, your clean side vessels must be totally isolated from dirtyside vessels. Same rules forcooking, cooked foods must not come into contact with surfaces or utensils used for prepping raw foods, particularly meats.
IMO, Sawyer provides the most effective systems re price and performance.

 

[PDA1]

Someone asked about floculant systems (polyglu?) here is a very goodlink.
http://www.cdc.gov/safewater/flocculant-filtration.html

More for stationary camp use than hiking