Water is life !
Clean drinking water is vital everywhere. Simple low cost and passive water filtration systems can be set up using gravel, sand and biochar. These can remove not only naturally occurring harmful bacteria but also man-made chemicals such as pesticides, pharmaceutical’s and other toxins and can easily compete with more expensive filtration systems or the need to bring in water from outside sources.
This is a open source design solution from Jon Jandi’s Punpun in Thailand