Kolleru Lake is the largest freshwater lake and is located in Andhra Pradesh. Kolleru is located between Krishna and Godavari delta and covers an area of 308 km².  The lake serves as a natural flood-balancing reservoir for these two rivers. The lake is fed directly by water from the seasonal Budameru and Tammileru streams, and is connected to the Krishna and Godavari systems by over 68 inflowing drains and channels. It serves as a habitat for migratory birds. It supports the livelihood of fishermen and riparian population in the area. The lake was notified as a wildlife sanctuary in November 1999 under India's Wild Life (Protection) Act, 1972, and designated a wetland of international importance in November 2002 under the international Ramsar Convention.