Abstract:
Negombo estuary. which is 3170 ha in extent, serves important economic functions
including fishing and tourism. It is characterized by high secondary production rates
reflected in important biomass values for benthic and pelagic organisms. Estuarine plants
and animals are adapted to high environmental variability and possess potentially valuable
genetic characteristics. However it is under heavy and increasing pressure li'0111 human
activities since it drains water carrying nutrients, organic matter and toxic. materials [rom
the terrestrial environment .and the river system to the sea. The disposal of waste oil from
the fishing anchorage located at the inlet and the direct discharge of partially and untreated
effluents from the Ekala and Katunayake industrial zones are the major contributors of
.pollution. The ad-hoc expansion of piers and landing points has lead the alterations in the
flow patterns and thus the sedimentation in the channels. Newly formed sand shoals have·
obstrncted the previously navigable areas. Unplanned development, unauthorized
encroachments to the water body and the siltation have reduced the effective water area by
791 ha during the last three decades. The eventual fate of this basin estuary would be
degradation by sedimentation and pollution.
