Assessment of Groundwater Quality of East Coastal Region in Tamilnadu, India

Abstract

Assessment of groundwater quality studies was carried out in the east coastal region (ECR) from Bamban to Thiruvanmiyur in Tamil Nadu, south India., to find the suitability of groundwater for drinking and irrigation purposes. Totally, 36 groundwater samples were collected randomly from bore well, dug well and hand pumps during summer, post monsoon, pre monsoon and monsoon periods of 2011. It has been made by estimating pH, electrical conductivity, total dissolved solids, total hardness, alkalinity, major cations of Na⁺, K⁺, Ca²⁺, and Mg²⁺ and major anions of CO₃^2-_, HCO₃^-  Cl^-, SO₄^2- and NO₃^-. Comparison with WHO standards Water Quality Index (WQI) in relation to drinking water quality proved that most of the water samples were found not suitable for drinking purposes. Domestic water quality parameters like, hardness and corrosives ratio revealed that most of the sampling locations were found unfit for domestic purposes. Chemical indices such as sodium percent, sodium adsorption ratio, residual sodium carbonate, permeability index, Kelley’s ratio and magnesium hazard / ratio used for evaluating the water quality for irrigation suggested that the majority of the groundwater samples were found not suitable for irrigation. Chemical indices indicated that groundwater quality in the study area was chemically unsuitable for drinking purposes, classified as unsuitable category for domestic purposes and 50% of sampling locations were unsuitable for irrigation purposes.