There are several solutions to water pollution that are low-cost, effective and sustainable that have already been successfully implemented throughout the world and are making a difference. Three of them are ceramic water purifiers, the SODIS method and in-situ filtration wells.
Potters for Peace Ceramic Water Filter Project
A Ceramic Water Purifier is a bucket-shaped vessel made from local clay, combustibles such as sawdust or rice husks, and colloidal silver. The clay and combustibles are mixed together and pressed in a two-piece aluminum mold and then fired at 860 degrees celsius, which burns away the combustibles leaving a porous surface. The filtration capabilities are tested and then the unit is coated in colloidal silver, and through both the small pores in the surface and the anti-bacterial properties of the silver it is able to filter out about 99.88% of water-borne disease agents. The filter can be placed in a five-gallon receptacle and water passed through it and the full cost for this system is between $15 and $25 and only $4 to $6 for a replacement filter. A production facility with 3-4 workers can produce about 50 filters a day and Potters for Peace works with local people to set up these facilities in countries around the world.
The SODIS Method
SODIS, or solar disinfection, is a simple method of using the sun to purify water by putting it in a transparent bottle and leaving it in direct sunlight for 6 hours. The bottles must be clean and it recommended that a PET (polyethylene terephthalate) bottle is used, but they can be reused as long as they remain transparent. Though this method requires low turbidity (cloudiness or haziness from suspended materials in water) and depends a bit on the weather, it is a low-cost and very sustainable method of purification.
In-Situ Filtration Wells
In-Situ Filtration Wells (ISF) are wells that combine hand constructions, low-cost hardware, minimal maintenance and the convenience and longevity of a drilled well. ISF wells contain more sand in their walls to enhance their filtration capabilities and can be made by local materials and local labor. Though the cost is a little more upfront ($400-$500 U.S. dollars) they cost 1/10th of a traditional well and are a great long term solution for providing clean water. They have been implemented successfully in Haiti and could be successful in other areas around the world.