On the cusp of disaster and development

From the high Himalayas to the plains, one of the largest tributaries of the Ganga has the power both to unleash disaster and to transform the country’s economy

Scroll over the map and explore more stories about the Koshi basin
The blue dots = hydrological monitoring stations


The Koshi River drains a large part of east-central Himalayas, flowing from Tibet and through Nepal before joining the Ganga in northern Bihar in India, which eventually flows to the Bay of Bengal. As one of the largest tributaries of the Ganga, the Koshi drains about 75,000 square kilometres — almost the size of Bhutan. It is one of the largest sediment-carrying rivers in South Asia. The basin boasts the world’s tallest mountain peaks including Mount Everest. In Nepal, it is called the Sapta Koshi — or seven Koshis — because seven Himalayan rivers merge to create it. The Koshi  is well known for its floods and capricious behaviour, having displaced millions in Nepal and India in recent years.

thethirdpole.net’s Nepal Editor Ramesh Bhushal and photographer Nabin Baral travelled along the tributaries of the Koshi River from near Tibet to the Indian border to report on the challenges faced by people living in the region.

Part 1:

Hazards in the high mountains

Part 2:

Roaring rivers, thirsty people

Part 3:

Dreams of hydropower dollars

Part 4:

River on the floodplains — best friend and worst enemy

The Bamboo Rafters