The Adyar River originates from the Chembarambakkam Lake and is an important river flowing through the city of Chennai. It merges into the Bay of Bengal at the Adyar Estuary. The Adyar Estuary is rich in flora and fauna. This river is 42 kilometers long.

It is possible to fish and boat in this River although most of the city`s waste is drained in this river. Migratory birds visit the Adyar Estuary and Creek and the Theosophical Society is on the Estuary`s southern side