International Journal of Applied Environmental Sciences ISSN 0973-6077 Volume 4, Number 2 (2009), pp. 165–172 © Research India Publications http://www.ripublication.com/ijaes.htm Assessment of Hydrochemistry of Groundwater in Muthupet Coastal Region, Tamilnadu, India S. Venkatramanan*, T. Ramkumar, S. Vasudevan, G. Ramesh, I. Anitha mary and V. Vijayakumar Department of Earth Sciences, Annamalai University, Annamalainagar-608002. *Corresponding author E-mail: earthvenkat@gmail.com Abstract This paper intends to assess the water quality with reference to domestic, irrigational and drinking uses in the Muthupet coastal region, Tamilnadu. This area underlain by quaternary sediments like alluvium, sandy clay, silt and fluviomarine sediments. The data were used to compute physico-chemical parameters. The groundwater nature of the samples falls in Na-Cl segments of the diamond shaped field. According to USSL classification of water quality of the samples belong to C3 S1, C3 S2, and C4S2 classes water are also found in the area which moderately suitable for irrigation. Keywords: Major ion chemistry, Hydrogeochemical facies, Drinking water quality, Muthupet, Introduction Water source have always been a precious commodity for human life. Water is used for a wide variety of purposes, chief among which are domestic, industrial, irrigation, hydroelectric power generation, navigation, recreation and fisheries development. The extent of a water use for any one purpose varies from one country to another and is dependent on a variety of factors like state of economic development, including standard of living; importance and extent of a specific sector like industry or agriculture in the national economy; efficiency of water use; socioculturar practices, and so on (Venkatesh et. al, 2005). An estimate by World Bank report that the year 2025, about 3.25 billion people in 52 countries will live in conditions of acute water shortage (Serageldin, 1995). Indian sub-continent is one of the wettest places on earth (Subramanian, 2000). The groundwater is the major source for domestic and agricultural activities in this study area.