The Tamur River is a major river in eastern Nepal

Nepal

Nepal , officially the Federal Democratic Republic of Nepal, is a landlocked sovereign state located in South Asia. It is located in the Himalayas and bordered to the north by the People's Republic of China, and to the south, east, and west by the Republic of India...

, which begins around Kanchenjunga. The Tamur and the Arun join the Sun Kosi

Sun Kosi

The Sun Kosi or Matsang Tsangpo is a trans-boundary river and is part of the Kosi or Sapta Kosi river system in Nepal. It originates in Tibet Autonomous Region of China.-Etymology:...

 at Tribenighat

Triveni, Nepal

Triveni is a village development committee in Udayapur District in the Sagarmatha Zone of south-eastern Nepal. At the time of the 1991 Nepal census it had a population of 6015 people living in 1105 individual households.-External links:*...

 to form the giant Saptakoshi

Koshi River

The Kosi River or Koshi —also Saptakoshi for its seven Himalayan tributaries—is a trans-boundary river flowing through Nepal and India. Some of the rivers of the Koshi system, such as the Arun, the Sun Kosi and the Bhote Koshi, originate in the Tibet Autonomous Region of China...

 which flows through Mahabharat Range on to the Gangetic plain

Kosi river system

The Kosi or Sapt Kosi drains eastern Nepal. It is known as Sapt Koshi because of the seven rivers which join together in east-central Nepal to form this river. The main rivers forming the Kosi system are – the Sun Kosi River, the Indravati River

Indravati River, Nepal

-Kosi river system:The Kosi or Sapt Kosi drains eastern Nepal. It is known as Sapt Koshi because of the seven rivers which join together in east-central Nepal to form this river. The main rivers forming the Kosi system are – the Sun Kosi River, the Indravati River, the Bhola Koshi, the Dudh Kosi,...

, the Bhola Koshi, the Dudh Kosi

Dudh Kosi

-Kosi river system:The Kosi or Sapt Kosi drains eastern Nepal. It is known as Sapt Koshi because of the seven rivers which join together in east-central Nepal to form this river. The main rivers forming the Kosi system are – the Sun Kosi, the Indravati River, the Bhola Kosi, the Dudh Kosi, the Arun...

, Arun River

Arun River (Nepal)

The Arun River is a trans-boundary river and is part of the Kosi or Sapt Koshi river system in Nepal. It originates in Tibet Autonomous Region of People's Republic of China where it is called Bum-chu.-Name:...

, Barun River

Barun River

The Barun River is a tributary of the Arun River and is part of the Kosi river system in Nepal.-Kosi river system:The Kosi or Sapt Kosi drains eastern Nepal. It is known as Sapt Koshi because of the seven rivers which join together in east-central Nepal to form this river...

, and Tamur River. The combined river flows through the Chatra gorge in a southerly direction to emerge from the hills.

The Sun Kosi contributes 44 per cent of the total water in the Sapta Koshi , the Arun 37 per cent and the Tamur 19 per cent.