Bellandur Lake is located in the suburb of Bellandur in the southeast of the city of Bengaluru. It is the largest lake in the city. It is a part of Bellandur drainage system that drains the southern and the south-eastern parts of the city. The lake is a receptor from three chains of lakes upstream, and has a catchment area of about 148 square kilometres. Water from this lake flows further east to the Varthur Lake, from where it flows down the plateau and eventually into the Pinakani river basin.

Lakes and tanks in the metropolitan area of Greater Bangalore and the district of Bangalore Urban are reservoirs of varying sizes constructed over a number of centuries by various empires and dynasties for rainwater harvesting. Historically, these reservoirs were primarily either irrigation tanks or for the water supply, with secondary uses such as bathing and washing. The need for creating and sustaining these man-made dammed freshwater reservoirs was created by the absence of a major river nearby coupled with a growing settlement. As Bangalore grew from a small settlement into a city, both of the primary historical uses of the tanks changed. Agricultural land witnessed urbanization and alternate sources of water were provisioned, such as through borewells, piped reservoir water and later river water from further away.