It is "non potable" for one of 3 reasons:
1. The provider does not want the legal liability (a common and understandable reason).
2. It has high mineral or chemical content. Nothing you can easily do about that but it is unlikely to be a problem for your intended usage except in very rare circumstances which include a radioactive source or similar.
3. It is or might be biologically contaminated (for example sources that come from creeks rivers and "rainwater"). Adding some chlorine will make it biologically safe and safe for your intended usages. Might not taste too good, but that won't matter. Add about 10 to 20ml of common household bleach per 100L.
Cheers,
Peter

Possum3 wrote:

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 Never consume water classified as non potable next to Dump Points, not even boiled. The bacteria in taps and hoses can cause serious injury even death.

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I have no qualms in treating such water with chlorine followed by filtration via 0.5um active carbon.

I understand that London's water is recycled 5 times on average.

Cheers,

Peter

For many years I have rough camped in the bush and used dam water (often very cloudy) and river water for hand and dish washing and showering - I have never suffered ill effects. In the shower I keep my eyes and mouth closed when washing my face/hair.

Depending where I am I nowadays treat river/dam water with 5mL of Milton (sodium hypochlorite) per 10L bucket, the increased incidence of e-coli due to farmed animal run-off make this a simple and sensible precaution.

Your gut has a significant ability to destroy "bad" bacteria and the amount which would collect on plates, cutlery and the like is well within your fighting range, indeed there is much to be said for a few e-coli to keep the immune system on its toes :)

 

Hi 

Two comments. First I would agree with Mike and have camped around over the years and used common sense to assess the water available. No problems. I have lived in third world countries also and again used common sense. But if on bottled water for drinking we showered and washed up using the normal water carefully. 

second the councils now will only label water non potable everywhere if it is not from their reticulated system and has not been tested to the standard. That's the way it is now. Even home tanks etc have to have 'non potable' signs on them. The lawyers have decreed it so 

Jaahn  

SO WHAT IS THE BEST WAY TO PURIFY WATER?

The surest method of purifying your water is to boil it. If youre camping with a gas cooker or open fire, it doesnt require any extra equipment. People will tell you different things about how long you need to boil water, one minute, three minutes, even as long as 15 minutes. In reality, you just need to bring the water to the boil. This will kill just about everything. It won't, however, remove toxins or chemicals which may be present.

The downsides to this method are obvious. If youre moving quickly its a pain to stop, set up a cooker, wait for the water to boil, and then wait another half an hour for it to cool enough to put in a bottle. Then you have several hours of drinking hot or warm water, which is no fun in the summer.

This is where water purification systems come in. Most work almost instantly.

A simple and popular option is water purification tablets. These are really just for short trips or emergencies. They work quickly and effectively but they often give the water a bit of a chlorine taste. You can purchase better-tasting pills that use other chemicals such as iodine. In any case, if you use them continuously they will start to take a toll on your health.

UV water purifiers are very quick, they dont change the taste of the water, and they scramble the DNA of any little buggies in your water so they wont reproduce and poison you. But these devices require a battery, and they tend to be a bit delicate. Theres nothing worse than getting caught on a long hike in a foreign country with a broken purifier.

Carbon filters are an excellent option, especially for camping. As well as removing bacteria, they take out dirt and sediment and actually improve the flavour of the water. Its entirely unnecessary, but for those extra-careful types, filters can be used in conjunction with tablets and will remove a lot of the chlorine flavour. Many filters wont be convenient for hiking, as they can weigh up to 1kg.