Subansiri River

{{Use dmy dates|date=May 2018}} {{Use Indian English|date=May 2018}} {{Infobox river | name = Subansiri | source1_elevation = | discharge1_location = | discharge1_min = | discharge1_avg = | discharge1_max = | discharge2_location = | discharge2_min = | discharge2_avg = | discharge2_max =  | source1 = Mount Porom | source1_location = | source1_coordinates = | mouth = Brahmaputra | depth_avg = | mouth_location = | mouth_coordinates = | mouth_elevation = | progression = | waterfalls = | river_system = | basin_size = | tributaries_left = | tributaries_right = | custom_label = | custom_data = | depth_max = | depth_min = | native_name = | pushpin_map_caption =  | name_other = Chayul Chu | name_etymology =  | image = Subansiri.jpg | image_size = 300px | image_caption = Subansiri | map = Ganges-Brahmaputra-Meghna basins.jpg | map_size = | map_caption = Map of the combined drainage basins of the Ganges (yellow), Brahmaputra (violet) and Meghna (green) including the Subansiri River | pushpin_map = | pushpin_map_size = | subdivision_type1 = | width_max = | subdivision_name1 = | subdivision_type2 = | subdivision_name2 = | subdivision_type3 = | subdivision_name3 = | subdivision_type4 = | subdivision_name4 = | subdivision_type5 = | subdivision_name5 = | length = | width_min = | width_avg = | extra = }} The '''Subansiri'''{{efn|{{langx|hi|सुबनसिरी नदी|Subansirî nadî}}; {{zh|t=西巴霞曲|p=xībā xiá qǔ}}}} ('''Chayul Chu''' in Tibet){{sfn|Huber|1999|p=146}} is a trans-Himalayan river and a tributary of the Brahmaputra River that flows through Tibet's Lhuntse County in the Shannan Prefecture in Southwestern China, and the Indian states of Arunachal Pradesh and Assam. The Subansiri is approximately {{convert|518|km|mi}} long, with a drainage basin {{convert|32640|km2|sqmi}}.<ref>{{cite book|last=Rao|first=K.L.|title=India's Water Wealth|url=https://books.google.com/books?id=DZNrXuA2y3MC&pg=PA78|access-date=1 May 2011|year=1979|publisher=Orient Blackswan|isbn=978-81-250-0704-3|page=78}}</ref> It is the largest tributary of the Brahmaputra contributing 7.92% of the Brahmaputra's total flow.<ref name="SinghSharma2004">{{cite book|last1=Singh|first1=Vijay P.|last2=Sharma|first2=Nayan|last3=Ojha|first3=C. Shekhar P.|title=The Brahmaputra basin water resources|url=https://archive.org/details/springer_10.1007-978-94-017-0540-0|access-date=1 May 2011|year=2004|publisher=Springer|isbn=978-1-4020-1737-7|page=[https://archive.org/details/springer_10.1007-978-94-017-0540-0/page/n94 82]}}</ref>

== Name and etymology == [[File:North-East Frontier in 1954 Political Map of India.jpg|thumb|right|250px|1954 map of the North-East Frontier Agency]]

Originally the name applied to the river only after the confluence of the Chayul Chu and Tsari Chu rivers at Gelensiniak.{{Sfn|Goyal|Gupta|Sarma|Singh|2017|p=523}} In early maps of independent India, Tsari Chu was marked as the main Subansiri river. However, over time, the name has been transferred to Chayul Chu.{{Citation needed|date=September 2023}} Within Tibet, the rivers are named after the locations they flow from such as Loro Chu, Nye Chu, '''Char Chu''' and Chayul Chu, all of which apply to the Subansirir or its tributaries.

And also in the Mising language, the river is referred to as Obonori. This name is distinct from the Sanskrit-derived Subansiri and has its roots in the indigenous Tani language. Obonori reflects the community's deep connection with the river, which is central to their culture, economy, and spiritual life. The exact etymology of Obonori is tied to the Mising people's unique linguistic and cultural heritage.

== Course == === Chayul Chu === Chayul Chu is formed near Chayul Dzong with the merger of '''Nye Chu''' and '''Loro Chu.'''

Nye Chu originates in the Tsome County where it is called Sikung. After entering the Lhuntse County, it is called '''Nyel Chu''' or '''Lhuntse Shung Chu'''. Its valley, called Nyelto, includes important towns such as Ritang and Kyitang, the latter the capital of Lhuntse County.{{Sfn|Dorje|2004|p=206}} It flows for about 100 km before reaching Chayul Dzong.

Loro Chu is formed by the merger two headwaters: '''Loro Karpo Chu''' (or the "White Loro River") and '''Loro Nakpo Chu''' (or the "Black Loro River"). Both the rivers originate in the Tsona County, marked by passes that divide the waters of Subansiri from those of Tsona Chu. The two head streams merge near the town of Trathong. The combined river flows for about 40 km before reaching Chayul Dzong.

Chayul Chu flows for about 50 km in Tibet before entering Arunachal Pradesh near the town of Taksing. Before this, it is joined by '''Char Chu''' near the village of Lung, and Yume Chu just before entering Arunachal Pradesh.

=== Subansiri === It enters India near the town of Taksing and flows east and southeast through Miri Hills,{{Sfn|Goyal|Gupta|Sarma|Singh|2017|p=523}} then south to the Assam Valley at Dulangmukh in Dhemaji district,<ref>{{Citation|last1=Barman|first1=Swapnali|title=Future flow scenario of Subansiri River and its Impact on Power Potential of Subansiri Lower Hydro Electric Project|date=February 2020|url=https://www.iitr.ac.in/rwc2020/pdf/papers/RWC_75_Barman_S.pdf|publisher=IIT Roorkee and NIH Roorkee|last2=Bhattacharya|first2=R.K.|last3=Sharma|first3=S.K.|last4=Tirkey|first4=G.}}</ref> where it joins the Brahmaputra River at Jamurighat in Lakhimpur district. Small tributaries of the Subansiri include Rangandi, Dikrong and Kamle.{{Sfn|Goyal|Gupta|Sarma|Singh|2017|p=523}}

The Subansiri lends its name to two districts in Arunachal Pradesh: Upper Subansiri and Lower Subansiri.

The observed discharge of Subansiri is a maximum of {{convert|18799|m3/s|cuft/s}}, and minimum of {{convert|131|m3/s|cuft/s|abbr=on}}. It contributes 7.92% of the Brahmaputra's total flow.<ref name="SinghSharma2004" />

== Tributaries == === Char Chu === {{expand section|date=December 2022}}

=== Tsari Chu === left|thumb|Tsari Chu marked in cyan '''Tsari Chu''' ({{zh|t=洛河|p=Luò hé}}, "Lo River"; known as '''Lensi River''' in Arunachal Pradesh)<ref>[https://arunachaltimes.in/index.php/2021/01/19/satellite-images-show-chinese-building-infrastructures-in-arunachal/ Satellite images show Chinese building infrastructures in Arunachal], The Arunachal Times, 19 January 2021.</ref> rises near the village of Chosam in Tibet and flows east for about 25 miles till the town of Migyitun, where it turns south. It merges with the Subansiri at Gelensiniak.<ref>{{Cite web|last=Kapadia|first=Harish|author-link=Harish Kapadia|date=2006|title=Secrets of Subansiri: Himalayan Journal vol.62/7|url=https://www.himalayanclub.org/hj/62/7/secrets-of-subansiri/|access-date=2021-01-23|website=Himalayan Journal}}</ref><ref>{{Cite web|last=Bhat|first=Col Vinayak|date=2018-06-22|title=Despite Modi-Xi bonhomie, China moves into Arunachal Pradesh, builds new road and barracks|url=https://theprint.in/defence/south-china-sea-to-the-himalayas-chinas-salami-slicing-now-reaches-arunachal/73316/|access-date=2021-01-23|website=ThePrint|language=en-US}}</ref> The district of Tsari, consisting of the Tsari Chu valley and its vicinity, is considered holy ground by the Tibetans. No animals are killed and no food is grown in these areas, with the exception of Migyitun.<ref>{{citation |first=F. M. |last=Bailey |title=Report on an Exploration on the North-East Frontier, 1913 |publisher=Government Monotype Press |location=Simla |year=1914 |url=https://archive.org/details/ExplorationOnTheNorthEastFrontier1913 |via=archive.org |page=10}}</ref> The holiness comes from the Dakpa Sheri mountain peak at the centre of the Tsari district, considered the home of the Buddhist Tantric deity Demchok (Chakrasamvara) and his consort Dorje Phagmo (Vajravārāhī). The pious Tibetans used to carry out a wide circumabulation (called ''rongkor'' or "ravine circuit") around the mountain once every 12 years, during the monkey year. They traversed the valley of the Tsari Chu river until its junction with Subansiri, and returned via the Subansiri and Yume Chu valleys.{{sfn|Krishnatry|2005|pp=2–3}} The last such circumambulation took place in 1956, after which the Sino-Indian border conflict has put an end to the practice.

== History == The 1950 Assam–Tibet earthquake caused landslides blocking the flow of Subansiri at Gerukamukh. After three days the blockade broke causing a massive flash flood. Over the years flooding of the river has caused loss to livelihood and life.{{Sfn|Goyal|Gupta|Sarma|Singh|2017|p=530}}

==Lower Subansiri Dam== The Lower Subansiri Dam or The Lower Subansiri Hydro-Electric Project is an under construction dam gravity dam on the river.<ref>{{Cite web|url=http://www.nhpcindia.com/Projects/english/Scripts/Prj_Introduction.aspx?Vid=23|title=एनएचपीसी-मिनी रत्ना कैटेगरी- I पीएसयू}}</ref> The dam is seen as a problem with environmental and social impacts and many organisations are protesting against it.<ref>{{Cite web|url=http://www.easternpanorama.in/index.php/component/content/article/60-2010/august/1103-anti-mega-dam-protests-vs-hydro-dollar-dream|title = Anti Mega Dam Protests Vs 'Hydro Dollar' Dream}}</ref> ''The River'' is a fiction book based on the issue and displays the issue as viewed by common Assamese people through its imaginary dolphins, fishes, and human characters.<ref>{{cite web |url=http://www.bubok.com/books/205665/THE-RIVER |title=THE RIVER - Ishan Kashyap Hazarika |website=www.bubok.com |url-status=dead |archive-url=https://web.archive.org/web/20141002030736/http://www.bubok.com/books/205665/THE-RIVER |archive-date=2014-10-02}}</ref>

==Notes== {{Notelist}}

==References== {{Reflist}}

== Bibliography == * {{citation |last=Dorje |first=Gyurme |title=Footprint Tibet Handbook with Bhutan |edition=3rd |url=https://archive.org/details/footprinttibet0000dorj |via=archive.org |url-access=registration |publisher=Footprint Handbooks |location=Bath |year=2004 |ISBN=1-903471-30-3 }} * {{Cite book |last1=Goyal |first1=Manish |last2=Gupta |first2=Shivam |last3=Sarma |first3=Arup |last4=Singh |first4=Dhruv |chapter=Subansiri: Largest Tributary of Brahmaputra River, Northeast India. |editor=Dhruv Sen Singh |title=The Indian Rivers: Scientific and Socio-economic Aspects |publisher=Springer |year=2017 |isbn=9789811029844 |pages=523–535 |chapter-url=https://books.google.com/books?id=ridFDwAAQBAJ&pg=PA522 |doi=10.1007/978-981-10-2984-4 |s2cid=187246753 |lccn=2017940312}} * {{citation |last=Huber |first=Toni |title=The Cult of Pure Crystal Mountain: Popular Pilgrimage and Visionary Landscape in Southeast Tibet |url=https://books.google.com/books?id=ac4PUrEtVtsC |year=1999 |publisher=Oxford University Press |isbn=978-0-19-535313-6}} * {{citation |last=Krishnatry |first=S. M. |title=Border Tagins of Arunachal Pradesh: Unarmed Expedition 1956 |publisher=National Book Trust |year=2005 |isbn=978-81-237-4460-5 |url=https://books.google.com/books?id=hXTaAAAAMAAJ}}

== External links == * [https://sandrp.in/2013/09/25/subansiri-basin-study-another-chapter-of-environment-subversion-in-northeast/ Subansiri Basin Study – Another Chapter of Environment Subversion in Northeast], South Asia Network on Dams, Rivers and People, 25 September 2013.

Category:Rivers of Assam Category:Rivers of Arunachal Pradesh Category:Tributaries of the Brahmaputra River