Assessment of Pesticides Contamination in Surface Water and Development of Nature-Based Treatment Technology: A Case Study of Rural Area of West Bengal, India

The aim of the chapter is to present the status of contamination level of surface water source and performance of the nature-based sustainable cost-effective water treatment technology developed in arsenic affected rural region at Rasui Village, Chatra Panchayat, North 24 Parganas District, West Bengal, India. It is observed that during the post-monsoon, the water quality of river named Padma is deteriorates with several pollutants such as pesticides, ammonia, and phosphate including turbidity. The surface water-based treatment involves modified multistage filtration (MSF), which comprises horizontal roughing filter (HRF) followed by slow sand filter (SSF) and activated carbon filter (ACF) for supplying treated water to local community. The treatment process consistently achieved higher removal efficiencies, ranging from 90 to 98% for turbidity, 80 to 90% for ammonia-N, 70 to 80% for iron, about 85% for nitrate, 60 to 90% for phosphate, and average different pesticides removal efficiencies vary from 70 to 85%.