Plastic bottle with a cap Craft knife Hammer and nail Coffee filter Large cup or mug (Either one works) Activated charcoal Sand Gravel Container to catch the water (jar, cup, mug, etc)

If you are a child, ask an adult to help you with this step Add handle so that you can hang it while it filters the water. Start by poking two holes near the cut edge of the bottle. Make the holes opposite of each other. Thread a piece of string through the two holes. Tie the string in a knot.

Charcoal can get very dirty. You can keep your hands clean by wearing some gloves.

Try using two types of sand: a fine grained sand and a coarse grained sand. The finer sand will go first, on top of the charcoal. The coarse grained sand will go next, on top of the fine-grained sand. This will create more layers for the water to pass through, and help make it cleaner.

Try using two types of gravel: a fine grained gravel and a chunky gravel. The fine grained gravel will go first, on top of the sand. The chunky gravel will go next, on top of the fine gravel.

If you are higher than 5,000 feet (1,000 meters) above sea-level, you will need to boil the water for at least three minutes. [2] X Trustworthy Source United States Environmental Protection Agency Independent U. S. government agency responsible for promoting safe environmental practices Go to source

If you don’t have a coffee filter, use a paper towel or a piece of cotton fabric instead. Make sure that the square is big enough to fit over the mouth of the cup. Try to use white fabric or a blank paper towel. Colored fabrics and paper towels contain dyes, which may bleed into the water.

Cut a 4 inch (10. 16 centimeters) long piece from a pine tree branch. Peel off the bark, and make sure that it can fit into the neck of the bottle. If it is too wide, shave it down using sandpaper or a pocket knife. Slide the first inch (2. 54 centimeters) or so of the stick into the neck of the bottle. Cut the bottom of the bottle off and turn the bottle upside down. Fill the bottle with water, and let the water drain through the stick. Do not let the stick dry out. If it dries out, it won’t be as effective. [7] X Trustworthy Source PLOS ONE Online peer-reviewed, open access scientific research journal Go to source