A study on groundwater quality and its characteristics in Tuticorin coastal region using geo-statistical approaches, Tamil Nadu, India

The aim of the present research is to identify the factors and processes to manage groundwater susceptibility using geostatistical techniques. Shortage of freshwater and drinking water are the major problems in the southeast coast of Tuticorin district, Tamil Nadu, India. Due to the different landscape and geological frame work across the coastal area, ever increasing population and manmade activities there is a necessity to check the groundwater quality in drinking and domestic water supply. Geostatistical analysis has been carried out through the field samples (24 nos) which were analyzed and visually interpreted in a graphical representation. The quality characteristics of the samples analysed using multivariate statistical analysis in the study area have been identified to be abnormal (EC, TDS, Cl and Na). The values are approximately 3 times exceeding the WHO standard for the villages of Sahupuram, Kayalpattinam, Arumuganeri, Vaalasamuthram and Arasadi spread over 300 km(2). Principle Component Analysis (PCA) indicates that the field of groundwater quality is predominantly associated with geogenic (rock-water interaction) and anthropogenic sources and domestic sewage. Findings of factors, cluster analysis (CA) and correlation matrix (CM) were also found to be consistant with the PCA results. It has been evident from the statistical analysis that the major groundwater quality is significantly influenced by EC, TDS, Cl and Na due to the inland salinity caused by seawater intrusion. Results of the study are expected to provide insights into taking effective action for groundwater quality protection by decision-makers on the Tuticorin coast of southern Tamil Nadu.