Chilka Lake is a brackish water lagoon, which is the largest brackish water lake in India. It is spread over Puri, Khurda and Ganjam districts of Odisha state on the east coast of India, at the mouth of the Daya River, flowing into the Bay of Bengal, covering an area of over 1,100 square kilometre. Brackish water or briny water that has more salinity than fresh water, but not as much as sea water. It may result from mixing of sea water with fresh water, as in estuaries, or it may occur in brackish fossil aquifers.