Outdoor Survival Tips: Filtering Water for Safe Drinking
Survival Guide: Shelter, Water, Food
Being stranded in the woods can be a daunting, frightening experience. Your first duties are to establish a safe base camp, -a place where you can remain safe, warm and dry. In other articles I have written about natural wildfoods you can gather, ways to build a fire and how to build modest tools from stone and rocks.
Your first and most pressing need however, would be for water. You can endure without food for days in an emergency but thirst can render you to a dire situation within hours. If you are fortunate, there might be a stream, creek or pond nearby. But in all likelihood, these waters will be impure and contain bacteria and protozoan that will quickly make you very sick. You need to create an ad hoc biologic filtering system to make the water safe and drinkable.
Depending upon your resources, you may have at hand a strong plastic bag to begin our water filter device. A plastic tablecloth can be folded and tied to produce a parachute-like configuration. You might even have an automotive inner tube that can be cut (using a stone knife that you created?) to make the basic filtering bag.
If you have shelter (a tarpaulin, for instance. Or, you might be stranded in your car in which case, you already have shelter) you could sacrifice a raincoat sleeve to create the water filter chute. -Your imagination must be used.
Survival School: The Basic Set-up of the Survival Water Filtering Bag
(primitive graphic by author)
Tie one end of the water filtering bag tightly closed, and the other end is tied to hold the bag-like device from a low-hanging strong tree limb.
Place several inches of new medium-ground charcoal (cold, from your campfire pit) into the bag first. Layer-in several inches of clean sand. This will hold the charcoal in place.
A next layer is small-to-medium gravel and pebbles. Again, this hold the sand in place. Another primary layer of clean filtering sand and a primary layer of pebbles and small gravel complete the water filter. Study the image to know the sequence.
Finally, using a can or bottle, add the raw water to the open end of the water filtering bag. This will take quite some time for the water to percolate down through the layers before you begin to see drippage. You will need to add more water a few times before you see any results, but eventually clean drinkable water will come through the layers and leak out of the bottom where the bag is tied-off.
This water will be fit to drink, having been filtered by the multiple layers of sand and charcoal. Once the filtering layers have been wetted the first time, adding more water will cause filtered water to come out more quickly to satisfy demand.
For it is worth mentioning, if you are stranded in your car without these provisions to build a water-fitlering system, you still have options. Removing the hubcaps from your car (especially metal hubcaps) and wipe the interior clean with your shirt or a cloth. Leave them out overnight where condesation and ice crystal might form. Early in the morning, check these. You might have enough frost and dew to provide a swallow of water. Even this little bit is better than nothing at all in a survival situation.
(all lmages, incl. thumbnail, by author)