Water filtration is a common household practice in developed countries, but not all denizens of the planet are afforded such luxuries. A random water source can harbor all sorts of pathogens, chemicals, and particulates, any number of which have the potential to cause serious health problems — waterborne illnesses account for the deaths of 1.7 million people annually worldwide. Water filtration is not just a matter of taste, it’s a matter of survival.
Fortunately, creating your own water filtration system is surprisingly elementary, using items that are easily found in nature but can also be purchased from a store. The main ingredient in many commercial water filters, as well as the DIY model in this post, is activated charcoal. Charcoal that has been treated with oxygen is referred to as “activated” charcoal, in which the oxygen works to create millions of tiny pores in the charcoal, allowing it to absorb tastes, odors, and particulates. More importantly, activated charcoal will also absorb volatile organic compounds (VOC) and chlorine, making it a heavyweight in the filtration arena.
It is crucial to differentiate between filtration and purification, however. Carbon-based filters will not remove microbes, nitrates, or most heavy metals. In order to ensure you have treated your water enough to safely drink it, you’ll want to purify it in some way after it’s been filtered.
There is a variety of ways you can accomplish this, including the use of purification tablets, tinctures, or even household hydrogen peroxide. Because many bacteria and viruses are anaerobic, the hydrogen peroxide overwhelms them with oxygen and destroys them. There are conflicting opinions on whether boiling is an acceptable option, as studies have shown that boiling found water actually helped release some toxins!
The following instructions for your own DIY water filtration system are easy enough for a child to understand, and would therefore make a great educational activity for the whole family. Construct a few of them so you have one for home, one for your camp gear, and one for the car, so that you always have ready access to filtered water!
• Plastic bag – a shopping bag, wastebasket liner, or large freezer bag
• String or twine to hang the bag
• Activated charcoal
• Container to collect the filtered water
1. Place a relatively thin layer of activated charcoal along the bottom of the bag.
2. Pour a thick layer of sand on top of the charcoal.
3. Place a layer of rocks on top of the sand.
4. Add another thick layer of sand, and then top with more rocks. Make certain there is ample room remaining at the top of the bag.
5. Hang the open bag from something, such as a tree limb, with the charcoal on the bottom.
6. Place your container below the bag, and snip a small hole in the bottom of the bag.
7. Add water to the top of the bag, and as gravity takes it down through the layers it is filtered, leaving you with water free from sediments, odors, and odd tastes.