CONSERVATION PLAN FOR ADYAR RIVER A DISSERTATION Submitted in partial fulfillment of the requirement for the award of the degree of MASTER OF TECHNOLOGY in “ENVIRONMENTAL MANAGEMENT OF RIVERS AND LAKES” by KARTHIK KUMAR.C ALTERNATE HYDRO ENERGY CENTRE INDIAN INSTITUTE OF TECHNOLOGY ROORKEE-247667 MAY 2015 ABSTRACT The origin of Adyar River can be traced to a point near Guduvancheri village, in Adanur Tank, though it assumes the appearance as a river only after receiving the surplus water from Chembarampakkam Lake as well as the drainage from the areas in the South West of Chennai. It flows through several villages of Kancheepuram and Chennai district for a distance of 42 km, collecting surplus water from surface drainages and many tanks and lakes, with a total catchment area of 1142 sq.km, to finally drain in the Bay of Bengal. The Adyar river has low velocity and discharge and does not carry enough water to sustain organic life in the river except during the North-West monsoon season. In the upstream of the river, there is less settlement along the banks and is not affected much by domestic sewage. It receives untreated agricultural runoffs. The use of fertilizers and pesticides for agriculture leads to contamination of soil, eventually they reach river through runoff generated by the rainfall as well as agricultural runoff. This leads to the increase in both nitrates as well as phosphates pollution and also contaminates groundwater of the river basin. Adyar River also has an estuary at its mouth, covering 149 Ha of area. About 23.5 ha of its part known as Adyar creek, an estuarine wetland, which is part of the ‘green lungs' of the city, provides a habitat for migratory birds and aquatic animals. Tamilnadu government has developed an ecological park. A conservational plan to restore from the ongoing deterioration activities was undertaken by Tamilnadu Government 2010 and works are still undergoing. However some important works like River front development, checking of industrial pollution, estimation of environmental flow, social assessment, and solid waste management for the project. The present study is a comprehensive conservation plan for river Adyar river. The water quality and quantity were measured during post and pre-monsoon. The analysis of collected samples of water showed that river faces serious pollution due to anthropogenic activities. The WQI of the river was calculated for both post and pre-monsoon. The water quality index of the river clearly shows that it’s unfit for drinking. iii Hydraulic model study of river was performed and results showed that river has significant chances to cause floods in the future. Interventions have been planned to improve the river channel and reduce the chances of flood. The requirement of sewage treatment plant has been studied and a proposal has been made to install STPs at few locations. A proposal also has been worked out to intercept these drains and to reduce the direct release of pollutants into the river. Common effluent treatment plants for the industries within the city limit or to follow the zero liquid discharge techniques has also been worked out. The cost involved in the various proposed conservation activities such as solid waste management, sewage and sanitation, river channel improvements have been estimated as Rs. 573.93 Crores over and above Tamilnadu Government plan for Rs. 350 Crores. iv .