Pollution in river Par and its abatement

Abstract

266-270Par River Estuary receives about 25,000 m3/day of effluent from a large chemical complex. The tidal effect at the present discharge point is weak and sufficient dilution water is not available except during spring tides. During monsoons, due to flushing, good water quality within the estuary is observed which, however, deteriorates after March when the river flow becomes negligible. The effluent does not mix well with sea water and flows downstream during the ebb tide. DO, BOD and pH show variation with the tidal stage. Flushing time computed employing tidal prism method is 1.4 tidal cycles while with fraction of fresh water method it is 4.4 days. Dye dispersion studies indicate that an appreciable fraction of the effluent would be washed to the sea during ebb tide if discharged about 3 km downstream