Water quality of Adimalathura Estuary, a small brackish water biotope (80 0? - 80 24? N latitude and 770 01? ? 770 03?E longitude) on the southern part of Kerala, exposed to pollution from domestic wastes and coconut husk retting was studied for a period of one year. All the physico-chemical parameters (transparency, temperature, salinity,pH, dissolved oxygen) and nutrients (nitrate, nitrite, phosphate and silicate) showed significant spatial and temporal variations. The water temperature was mostly influenced by atmospheric temperature. Presence of suspended matter lowered the transparency at the polluted station. Salinity variations were more conspicuous than the variations in other parameters analysed. The sea-estuary interaction and land drainage influenced salinity distribution. Concentration of dissolved oxygen was low at polluted station. Nutrients (No3-N, No2-N, PO4-P and SiO4-Si) in general showed significant spatial and temporal variations and high values were observed at the polluted station.

Hydrography, Adimalathura Estuary, Kerala, coconut husk retting, pollution