Eutrophication of water bodies like lake, pond, shallow stretches of river, etc. is the phenomenon where excess growth of vegetation on the surface of the water takes place. This excess growth results in the clouding of the water, depletion of dissolved oxygen in water, and the death of aquatic organisms. The primary reason for the cause of eutrophication is the presence of nutrients in excess amounts in the water. The nutrients B. come from fertilizer and sewage runoff.