Riverbank filtration in India – using ecosystem services to safeguard human health

Abstract

India has great potential to use riverbank filtration (RBF) for drinking water production as an ecosystem service for human health, principally through effective removal of common waterborne pathogens, even during monsoon. Water quality results from site investigations in North India have shown a removal of total and faecal coliform (indicator) bacteria in the range of 1.3 to >5.2 log for total coliforms and 2.3 to >4.2 log for faecal coliforms at the bank filtration schemes of Haridwar, Nainital, Patna, and Mathura. At rural RBF sites, where bank filtrate is collected and supplied by Koops (‘well’ in Hindi), a removal of 1.0–3.4 log and 0.3–2.8 log was observed for total and faecal coliforms respectively. At the RBF sites in Haridwar and Patna, there was only minimal breakthrough of coliforms during monsoon floods, for which disinfection using conventional chlorination was sufficient.