Environmental impact assessment for Tamiraparani river basin, Tamil Nadu, South India

Abstract

Monitoring the surface run-off of a river on a regular basis provides valuable information on the eco-hydrologic conditions of a river basin. Such data provide valuable insights into spatial and temporal variation in water quantity and quality, considered as a measure of the health of a river. Such data are also a measure of the reliability of water quality models and their predictability. The physicochemical characteristics of any aquatic ecosystem and the nature and distribution of its biota are directly related and to influence by each other and controlled by a multiplicity of natural regulatory mechanisms. Because of it man s exploitation of the water resources, the normal dynamic balance in the aquatic ecosystem is continuously disturbed and often results in each dramatic response as depletion of fauna and flora, fish kill, change in physicochemical character etc. The river Tamiraparani is one of the few perennial rivers of the southern peninsular India extending between the latitude 8°10´ and 9°13´ N and longitude 77°10´ and 78°10´ E. The river originates in the eastern slope of the Western Ghats at an altitude of 2000 m above mean sea level. The river wander through a distance of about 125 km with a drainage area of 5896 km2 and drains through three important geological formations, Archean rocks, Tertiary and recent sediments. The seven important tributaries of the river are Servalar, Karayar, Chittar, Manimuthar, Gadana, Pachiyar and Ramanathi. The present study focuses on greater details, of the spatial and temporal variations of river quality parameters such as physicochemical, organochlorine pesticides and pathogenic indicator microorganism loads of water and sediment constituents in the river. The first phase of the present study focuses on the spatial and temporal distribution changes of major ions, nutrients, and its transport characteristics within the river and its flux to the Bay of Bengal.