|Son River (Sone सोन)|
|States||Madhya Pradesh, Uttar Pradesh, Jharkhand, Bihar|
|- left||Ghaghar River, Johilla River|
|- right||Gopad River, Rihand River, Kanhar River, North Koel River|
|Cities||Sidhi, Dehri, Patna|
|- elevation||600 m (1,969 ft)|
|Length||784 km (487 mi)|
The Son originates near Amarkantak in Madhya Pradesh, just east of the headwater of the Narmada River, and flows north-northwest through Madhya Pradesh state before turning sharply eastward where it encounters the southwest-northeast-Kaimur Range. The Son parallels the Kaimur hills, flowing east-northeast through Uttar Pradesh, Jharkhand and Bihar states to join the Ganges just west of Patna. Geologically, the lower valley of the Son is an extension of the Narmada Valley, and the Kaimur Range an extension of the Vindhya Range. Dehri on sone and Sonbhadra are the major cities situated on Son River.
The Son river at 784 kilometres (487 mi) long, is one of the longest Indian rivers. Its chief tributaries are the Rihand and the North Koel. The Son has a steep gradient (35–55 cm per km) with quick run-off and ephemeral regimes, becoming a roaring river with the rain-waters in the catchment area but turning quickly into a fordable stream. The Son, being wide and shallow, leaves disconnected pools of water in the remaining parts of the year. The channel of the Son is very wide (about 5 km at Dehri on sone) but the floodplain is narrow, only 3 to 5 kilometres (2 to 3 mi) wide. In the past, the Son has been notorious for changing course, as it is traceable from several old beds near its east bank. In modern times this tendency has been checked with the anicut at Dehri, and now more so with the Indrapuri Barrage.
Sir John Houlton, the British administrator, described the Son as follows, "After passing the steep escarpments of the Kaimur range, it flows straight across the plain to the Ganges. For much of this distance it is over two miles wide, and at one point, opposite Tilothu three miles wide. In the dry weather there is a vast expanse of sand, with a stream not more than a hundred yards wide, and the hot west winds pile up the sand on the east bank, making natural embankments. After heavy rain in the hills even this wide bed cannot carry the waters of the Son and disastrous floods in Shahabad, Gaya, and Patna are not uncommon."
The first dam on the Son was built in 1873–74 at Dehri.
The Bansagar Dam in Madhya Pradesh was commissioned in 2008.
The 1440-metre rail and road lattice-girder concrete and steel Abdul Bari Bridge (previously but widely still called the Koilwar Bridge and before that the Son Bridge) near Arrah was completed in 1862. It remained the longest bridge in India, until the Nehru Setu bridge at Dehri was opened in 1900.
The modern Son bridge built in Deolond, Shahdol district of Madhya Pradesh was inaugurated by Motilal Vora and Pandit Ram Kishore Shukla then Chief Minister and Finance Minister of Madhya Pradesh on 13 February 1986.
- "Baburnama". 1590s.
- Sir William Wilson Hunter. Imperial gazetteer of India, Volume 23. pp. 76–78. Retrieved 2014-06-06.
- Houlton, Sir John, Bihar, the Heart of India, pp. 47–48, Orient Longmans, 1949.
- "Performance Evaluation of Patna Main Canal" (PDF). ICAR Research Complex for Eastern Region,. Retrieved 2011-07-08.
- "Bridges: The Spectacular Feat of Indian Railways" (pdf). National Informatics Centre. Retrieved 2011-07-05.
- "Longest railway bridge in Kochi". ForumCo.com. Retrieved 2011-07-07.
- "Arwal". The Bihar, 31 March 2010. Retrieved 2011-07-03.
- "Four-lane connector over Sone, Ganga". The Telegraph, 8 April 2011. Retrieved 25 June 2011.
|Wikimedia Commons has media related to Son River.|