How sand and gravel can clean your drinking water
  • 6 years ago
The system follows a four-step water filtration process -- predation, adsorption, mechanical trapping and natural die-off. Shivani Kumar, India representative of South Asia Pure Water Initiative Inc (Sapwii), has come to India to conduct training workshops to convince not-for-profits and government officials to adopt the BioSand Filter method for cleaning water.