IMPACT OF URBANISATION ON WATER QUALITY PARAMETERS – A CASE STUDY OF ASHTAMUDI LAKE KOLLAM

Nagaraj Sitaram

Abstract: The Ashtamudi Lake in the Kollam District of Kerala lies in between 76.53°and 76.63° longitude and 8.93° and 8.83° latitude. It is a palm-shaped extensive waterbody with eight prominent arms, adjoining the Kollam town. This extensive estuarine system has a length of 16 km with a maximum width of 14 km and maximum depth up to 6.4m covering an area of 64.2 km2 . The Ashtamudi Lake has been designated as a Ramsar Site (No.1204) in November 2002 and is also a major tourist place. It supports around 43-marshy mangrove species, 57-species of birds, 97-species of fishes and some unique copepod species which are important sources of food. More than 20,000 waterfowl visit the lake annually. Coconut husk retting, fishing, inland navigation and a fishing harbour at Neendkara are other benefits provided by this lake. The case study describes the effect of urbanisation on water quality parameters and suggest for its improvement. The water spread area for Ashtamudi Lake in these three years are found to be shrinking (1999 – 6424 ha, 2003 – 6140 ha, 2006 – 5734 ha). The detailed physico-chemical and biological examinations are collected for three years (1999, 2003, and 2006) made during pre-monsoon season for various locations and their average values are reported. A comprehensive plan is prepared to restore the water quality of Ashtamudi Lake near the Kollam City

Keywords: WATER QUALITY

DOI: https://doi.org/10.15623/ijret.2014.0318023