Managed aquifer recharge by a check dam to mitigate the problem of fluoride rich groundwater a case study

Abstract

The water demand is globally increasing due to the growing population. This increasing demand is obviously reflected by the use of groundwater, leading to negative environmental effects such as overexploitation and groundwater pollution. In many regions around the globe including India degradation in the quality of groundwater is of great concern. Groundwater with ionic constituents beyond the recommended levels is not fit for domestic purpose as prolonged use is harmful to human health. Groundwater with fluoride concentration above the recommended limits are widespread in several regions of the world. This is of great concern as more than 200 million people in the world, including India, have been affected by dental and skeletal fluorosis due to consumption of fluoride-rich groundwater. In India, 2% of children are affected by dental fluorosis. Krishnagiri district in the western part of Tamil Nadu, India is one such region where groundwater has fluoride concentration greater than the permissible limits of domestic use. Many studies have reported the locations in which the concentration of fluoride has exceeded the permissible limits, the sources and the geochemical processes responsible for the release of fluoride from rocks. However, these studies have not attempted to assess the feasibility of increasing recharge to mitigate the problem of fluoride rich groundwater. Hence the present study was carried out with the aim of assessing the efficacy of check dam as a method of managed aquifer recharge to reduce concentration of fluoride in groundwater and improving its quality for domestic and agricultural use in Pambar River sub basin in Krishnagiri District, Tamil Nadu, India. For this purpose, the collection and analyses of soil, rock and groundwater samples were made around a check dam located across Pambar river in the study area. newline