The Manas River
The Manas River is a transboundary river in the Himalayan foothills between southern Bhutan and India. It is named after Manasa, the serpent god in Hindu mythology. It is the largest river system of Bhutan, among its four major river systems; the other three are Amo Chu or Torsa, Wong Chu or Raidak, Mo Chu or Sankosh.

It is met by three other major streams before it again debouches into India in western Assam. The total length of the river is 376 kilometres (234 mi), flows through Bhutan for 272 kilometres (169 mi) and then through Assam for 104 kilometres (65 mi) before it joins the mighty Brahmaputra River at Jogighopa. Another major tributary of the Manas, the Aie river joins it in Assam at Bangpari.

Amo Chhu or Torsa
Bumthang River or Murchangphy Chhu
Dhansiri Nadi
Drangme Chhu
Eastern Bhutan
Ha Chhu
Jaldhaka River or Di Chu
Kulong Chhu
Kuru Chhu or Lhobrak
Manas River
Mangde Chhu or Tongsa
Mo Chhu or Sankosh River
Pagladiya River
Paro Chhu
Pho Chhu
Puthimari Nadi
Tang Chuu.
Tawang Chhu or Gamri
Thimphu Chhu
Western Bhutan
Womina Chhu
Wong Chhu or Raidak