Effects of domestic and industrial effluent discharges into the lake and their impact on the drinking water in Pandravedu village, Tamil Nadu, India

Increasing demand for water from agriculture, industrial and domestic sectors, resulted in stress on the water resources both from quantity and quality perspectives. Due to urbanization many of the dyeing units have shifted from urban to nearby rural areas. Here safe disposal of untreated effluent from the dyeing units is a challenge and is often let into nearby water bodies. Pandravedu Lake, located in Thiruvallur district of Tamil Nadu, India is one such case were the present study is carried out. Water samples were collected from twelve locations during premonsoon, monsoon and post-monsoon seasons, in pre-cleaned polyethylene cans and analyzed for physicochemical parameters like pH, total dissolved solids, electrical conductivity, total alkalinity, total hardness, calcium, magnesium, sodium, potassium, iron, nitrate, chloride, fluoride and sulphate following the standard analytical procedures recommended by American Public Health Association (2005). The analytical results indicated that 40% to 70% of samples exceeded the drinking water quality standards prescribed by Bureau of Indian standards (BIS, 2012). Water quality index computed indicate that both the bore wells that supply drinking water to the village falls in very poor category (101 - 150) across three seasons. Correlation analysis indicated that seasonal changes in correlation among the parameters are linked to the fluctuations of wastewater discharge and its characteristics.