Abstract

                                Contamination of the water resources has increasingly become a serious problem in many of the States including Tamil Nadu due the domestic and industrial waste waters. Only limited studies are available to comprehend the water quality of Noyyal river basin. Hence, this study was undertaken to characterise the quality of surface waters in Noyyal river and its adjoining tanks. The Noyyal river is continuously polluted due to many industries situated on its banks of the river. Textile and dye industries are the major industries that pollute the river. Twenty water samples were collected from various points of rivers and tanks during pre and post monsoon seasons of 2006 to 2007 and analysed for chemical parameters. The E.C. and pH values varied from 0.17 to 8.70 dSm -1 and 5.39 to 8.63 in river water. Cations were in the order of Na>Mg>Ca>K. Around 61.5 per cent of samples found to show RSC values of >2.5 m.e L -1 . SAR/SCAR values indicates that most of the samples (46 %) come under medium sodium class (S 2 ). The EC and pH values of tank water samples varied from 0.41 to 3.13 dSm -1 and 8.0 to 8.5 respectively. Majority of the samples (57 per cent) found to show RSC values of <1.25 m.e L -1 .SAR values indicates that most of the tank water samples (71.4 %) come under Low Sodium Class (S 1 ). Seasonal variations in water quality parameters were also observed in river and tanks.

Key words : Industrial pollution, surface water quality, Noyyal river basin, Tamil Nadu.