Impact of Municipal and Industrial Liquid Wastes on Water Quality and Its Importance as Potential Water Resources

Abstract

The results obtained amply establish the fact that systematic management of wetland fed by municipal wastewater and industrial runoff not only solves the problem of environment pollution but also balances the ecosystem. The major adverse impacts of sewage on water quality are deoxygeneration, high biochemical oxygen demand (BOD) load, rapid eutrophication, and accumulation of heavy metals in the environment. A study of water quality in a purified fish cultivated pond of Mudially wetlands near Kolkata city was undertaken in respect of physico-chemical properties and heavy metal content in sediments,water, fish, and water-hyacinth in different years.The quality of effluent, as well as sediments, fish and water-hyacinth in respect of pollutant was much better in the year 1998 in respect to 1994. This is due to effective purification of polluted effluent in different stages of pond and tank by both natural and in chemical ways. The effluent contains high amount of protein rich compound which is a good food for fishes. The yield of fish is high and it is expected that such a system will be able to satisfy the improvement of wastewater quality, fish production, and ecological balances in environment.