A lake with an inflow of domestic sewage rich in organic waste may result in:
Drying of the lake very soon due to algal bloom
Death of fish due to lack of oxygen
Eutrophication is the excessive richness of nutrients in a lake or other body of water, frequently due to run-off from the land, which causes a dense growth of plant life. One of the negative impacts of eutrophication and increased algal growth is a loss of available oxygen, known as anoxia. These anoxic conditions can kill fish and other aquatic organisms such as amphibians living in the water bodies.