Pollution Status and Conservation of Lakes in Coimbatore, Tamil Nadu, India

Economic development is accelerating the changes in the land use pattern and land-cover conversion almost throughout India at an unprecedented rate. Wetlands and lakes especially those situated in the vicinity of urban centres have been facing rapid degradation due to liquid or solid waste disposal, filling and reclamation, real-estate ventures and industrial development. Coimbatore, a rapidly developing city in the western part of Tamil Nadu, has several wetlands and lakes in and around its limits. This city wanting facilities for treatment of industrial, municipal, domestic and hospital waste has open drainage and sewerage systems which joining these lakes without any prior treatment. The present study undertaken in Coimbatore during May 2008 on four urban lakes / wetlands namely Ukkadam, Perur, Kurchi and Chinnakulam reports the water quality of these water bodies with reference to the pollution from various sources. The pH for water samples ranged between 7.64 and 8.62. EC and TDS ranged from 303.67 - 4456.7 μS/cm and 169 - 2079.3 mg/L respectively and were positively correlated with chloride and sulphate (P < 0.05). Ukkadam lake, surrounded by textile dyeing industries, municipal markets, dumped domestic wastes was the most polluted among the lakes studied. This lake receives sewage waste along with effluents from dyeing industries through various channels. In view of the findings, recognizing the various ecological services these wetlands offer to the city and its environs regular monitoring of disposal of solid / liquid wastes and sewage discharge is imperative for their conservation.