Cuddalore District, East Coast of India

The study area enjoyed artesian conditions few decades back but at present frequent failure of monsoon and over exploitation threatens the quantum of groundwater. Further, urbanization, extensive agricultural and industrial activities has deteriorated the quality of groundwater. The study was carried out to identify the sources responsible for the change in quality of groundwater as well as to evaluate the suitability of water to irrigation. Results of the study illustrates that the seasonal effect does not change the order of abundance of both cations and anions, but it changes the concentration of various ions present in the groundwater. Geochemical nature of water is determined using piper diagram wherein the results show the predominance of CaMgCl and CaHCO3 types. Equiline diagrams were applied to evaluate the relationship between various ions present in these waters. Results of Gibb’s diagram show that the mechanism of the chemical budget of this water is mainly due to rock-water interaction. The geochemical data was interpreted using Kelly’s ratio, Magnesium ratio, SAR and Wilcox diagram and the results shows that about 70 % of the groundwater is suitable for irrigation