The Ennore estuary and Kosasthalaiyar River have long been affected by industrial effluents, sewage, thermal discharges, and fly ash from nearby industries and thermal power plants. Studies have shown that heavy metals and other pollutants are being released into the water, altering its quality and causing harm to aquatic life. These pollutants can lead to oxygen depletion and other changes in water chemistry, which are detrimental to marine ecosystems.