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November 2014 Issue
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Making sure your water’s safe

A sock filled with sand, stones and charcoal, can be used to filter water.
You can survive for weeks without food, but only about three days without water. So being able to access clean, safe water is extremely important when in the outdoors. But what is the best source of drinking water and how can you treat it? Nathan Watson explains

Picking a source

It is important to find the cleanest possible source of drinking water. Even water that looks perfectly clear may harbour a variety of bacteria and parasites that can make you ill.

The best source of water is likely to be a stream, creek or spring that has clear flowing water. Make sure it is not below a track or near any area where livestock may be kept.

Lakes and ponds are less ideal – stay away from stagnant pools of water. If you must take water from a lake, try to access it from the inlet rather than the outlet. Avoid recently flooded rivers, swimming spots or areas where animals may live.

A sock filled with sand, stones and charcoal, can be used to filter water.

Boiling water

If you’re boiling water for cooking, then the water will be sterilised. It is not necessary to use filtering or chemical treatment after boiling.

If you need to boil water but don’t have a container you can use a supermarket plastic bag on the embers of a fire (no flames!) Fill the bag half-way with water, remove as much air as possible, securely tie the top and place it onto the embers. It will slowly start to boil and if done properly, the bag will not melt!

Filtering water – the sock and charcoal method

If you can’t boil your water, an alternative option is to create a makeshift water filter to remove some of the contaminants. One way is to gather up a piece of cloth (or use a sock), fill with sand, stone and charcoal (this can be taken from an old fire). Over a container, pour the water into the cloth-charcoal mix. You should then be left with (reasonably) good drinking water. You can also purchase water filter systems at most outdoor retailers.

Nathan Watson is the former Outdoor Land Safety Manager for the Mountain Safety Council