Arkavathy River is a river, which originates at Nandi Hills of the district of Kolar. The Arkavathy River is also considered to be an offshoot of River Cauvery. After flowing through the rural districts of Bangalore and Kolar, River Arkavathy merges at the Kanakapura confluence. The catchment area of River Arkavathy is about 4351 square kilometers. Although the origin of the Arkavathy River is traced to the southern foot of the Nandi Hills, which is 3000 meters above the sea level, the real source of the river lies in the two series of about 26 tanks that join the Nagara Kere tank in the town of Doddaballapur. It is from here that the Arkavathy River flows as one though the rural district of the Bangalore city. The Arkavathy River flows through a deep gorge here. The total length of the Arkavathy River is 190 kilometers. The big and small tanks that is there on its flow amounts to 150 and 1084 respectively. Arkavathy River is the only sub-basin in the present times. This sub-basin is again divided in three parts, that is Rural, Peri-Urban and Urban areas.