Most of the lakes whether natural or man-made , are directly or indirectly associated with the river systems. There is an organic relations hip between the lakes and river systems. Lakes serve as an important life support system by helping in recharging of acquifers and regulating hydrological regimes. They also act as natural traps for sediments and nutrients thereby helping to regulate water quality and sedimentation of the river systems from the catchment area. They carry out a crucial role as breeding grounds for fish and other aquatic life.
Lakes also constitute habitats for a variety of birds, fishes and other aquatic life.
The lakes, particularly the urban lakes, are in varying degrees of environmental degradation. The main cause is rapidly increasing population in the catchment areas of lakes and industrialization. Both domestic sewage and industrial effluents have been causing serious pollution of these precious Water bodies. Besides encroachments, deforestation in the catchment areas leading to siltation and flow of pesticides from the agricultural wastes are the other major causes. The result is that the lakes are becoming increasingly unfit as a source of drinking water, recreational activities and habitats for aquatic life.