Potential for River Bank Filtration in Arsenic-Affected Region in India: Case Study

AbstractHigh concentrations of arsenic in groundwater, affecting the districts lying on either side of the Ganga River in India, are reported as a serious environmental issue. Groundwater that is dominated by the presence of arsenic is not suitable for domestic consumption. Recharge of abstraction wells using river water may dilute the arsenic concentration in groundwater. Experiments were conducted to monitor arsenic concentration in the river and an abstraction well for a period of more than six months at a study site located near Patna, Bihar, India. A model to explain the variation of arsenic concentration in the abstracted water is developed. The model assumes that no arsenic is picked up from the porous media as river water travels through the porous media to reach the abstraction well. The contribution of groundwater or river water to the abstraction water is found to be related to the depth of water in the river. Such an approximate relationship is utilized in simulating the arsenic concentration. The simulated values appear to be in good match with observed values.