Aquatic Pollution and Coastal Management

Unit 11 : Monitoring and control of pollution

11.3.3.Goa Coast
In general, the coast is sandy. The prominent river outfalls are Mandovi and Zuari. Only two pharmaceutical units are located at Panaji and Corlim. In addition, untreated and partially treated sewage is let into these rivers. One of the major concerns in the state is the contaminant load on the Mandovi and Zuari estuarine system from the mine rejects dumped along the shore which are ultimately transported into the coastal sea. It has been estimated that mining activity resulted in the accumulation of 300 million tons of tailings through rivers. This was responsible for the following changes in the ecosystem.

• Overall 66% reduction in the dissolved oxygen content.
• Increased suspended solids.
• Substratum is blanketed by red clay, lateritic soil and cobble.
• Reduction in shellfish population from 500 to 10 gm/m².
• More than 5% reduction of benthic population.