Chapter 13 - Potential tools for identification of saltwater intrusion into the coastal aquifers: A case study from East Coastal Regions of India

Abstract

Saltwater intrusion into coastal aquifers has now become a global problem. In the present study, potential tools for its identification have been discussed and tested on a saltwater-intruded area along the Eastern coast of India. Subsequent to collecting and analyzing water samples, hydrochemical tools such as hydrochemistry, ionic ratios, and evolution of hydrochemical facies have been applied to extract useful information on the impact of saltwater intrusion on coastal water quality. Further, the degree of seawater mixing with the coastal groundwater has been estimated by calculating seawater fractions and seawater mixing index. The multivariate statistical analysis showed a close association among various water quality parameters and provided a confirmative insight of geochemical processes controlling the coastal groundwater quality. Furthermore, geospatial methods helped in understanding the spatial distribution of saltwater in coastal regions leading to identification of potential freshwater pockets in saltwater-affected regions. Therefore, the application of geochemical, statistical, and geospatial techniques in an integrated fashion can effectively be used for the identification of saltwater intrusion and potential freshwater zones in coastal aquifers.