Now I am going to take you a bit back in time, and to a place very far from India. Last March as I walked down Thayer Street, bracing against the cold wind that was the last gasp of a long New England winter, one of the many academic flyers vying for attention caught my eye. It announced a lecture about water purification in a series entitled “Innovative Approaches to Global Health.” As I was (and still am) looking for social applications of earth science, I did a quick web search on the speaker, Geology Professor Tom Boving at the University of Rhode Island. He has received funding from the World Bank and the Bill and Melinda Gates Foundation to develop a novel technique for water filtration in the tropics.
The process of riverbank filtration (RBF) involves pumping river water through a riverbank. Both physical and microbial processes help to remove organic and inorganic contaminants from the surface water. This technique has actually been used in the Rhine river valley in Germany for hundreds of years, but never in a monsoon climate like in India. Professor Boving and his colleagues have adapted this low-cost method to serve 2000 people in a rural area of Karnataka state near the TERI office in Goa.
I plan to spend three weeks working with TERI, including one week taking water quality measurements at the field site in Karnataka. I look forward to learning more details of the science and management involved in the project. Some questions I plan to investigate include:
- What specific geochemical reactions occur as the river water moves through the soil?
- Which contaminants is RBF best at removing?
- Does the riverbank have a finite filtration capacity?
- What challenges does the tropical monsoon climate regime pose for RBF, and how has TERI modified the traditional RBF technique to address these challenges?
- I know that there is a small charge for villagers to use the water. Who do they pay, and how did TERI decide that?
Stay tuned to hear about my findings!