The Sabarmati river is one of the biggest rivers of Gujarat. It originates in Dhebar lake in Aravalli Range of the Udaipur District of Rajasthan and meets the Gulf of Cambay of Arabian Sea after travelling 371 km in a south-westerly direction. The Sabarmati basin has a maximum length of 300 km. and maximum width of 105 km. The total catchment area of the basin is 21674 km2 out of which, 4124 km2 lies in Rajasthan State and the remaining 18550 km2 in Gujarat State.It is believed that earlier the river used to flow from Manek Chowk.
The National Water Quality Programme led by Central Pollution Control Board (CPCB) positions Sabarmati River as one of the most polluted rivers in India. Sabarmati River Basin is situated in the mid-southern part of Rajasthan. To its east lie the Banas and Mahi Basins, to its north the Luni Basin and to its west the West Banas Basin. Its southern boundary is the border with Gujarat State. The Sabarmati river basin extends over parts of Udaipur, Sirohi, Pali and Dungarpur Districts. Orographically, the western part of the Basin is marked by hilly terrain belonging to the Aravali chain. East of the hills lies a narrow alluvial plain with a gentle eastward slope.
The main tributaries of the Sabarmati river are Wakal river and the Sei Nadi, which also rise in the Aravali hill range west of Udaipur city and flow south-westwards in courses generally parallel to the Sabarmati river, up to their confluence with the river (in Gujarat).
The origin legend is that Shiva brought the goddess Ganga to Gujarat and that caused the Sabarmati to come into being.Ahmedabad and Gandhinagar, the commercial and political capitals of Gujarat, were established on the banks of Sabarmati river. The legend is that Sultan Ahmed Shah of Gujarat, resting on the bank of Sabarmati, was inspired by the courage of a rabbit chasing a dog to the extent of establishing Ahmedabad in 1411. The soils of the Sabarmati area on the banks of the river are rich.
The area covering upper sub-basin and the catchment of the main river up to Dharoi dam is designated as Dharoi sub-basin. Constructed in 1978, Dharoi dam is located about 165 km upstream Ahmedabad in village Dharoi of Mehsana district. This covers drainage area of the main river up to Dharoi dam. Catchment area of the sub basin is 5540 km2, out of which about 2,640 km2 lies in Gujarat state.