From Tibet to West Bengal, the Brahmaputra is the pulse of communities and ecosystems along its course. But what are the risks the river faces through human interventions, particularly dams, discusses journalist, author and filmmaker Sanjoy Hazarika in his new book, River Traveller. Excerpts from an interview with Down To Earth:
Rajat Ghai (RG): You have spent years criss-crossing the Brahmaputra basin and belong to Assam. What observations have struck you most?
Sanjoy Hazarika (SH): My earliest memories of the river are of its vastness and of seeing dolphins playing in it in Guwahati when I was a child. I have travelled along many rivers around the world, but this is the one I know well and have seen it from the upper reaches down to the Bay of Bengal. As a result, it carries not just symbolic meaning but a deep, anchoring presence in our lives, culture and history of Assam.
I have travelled through Tibet, Arunachal Pradesh, Assam and Bangladesh. For me, the most striking part of that journey was Tibet. It is alluring, mysterious, with a politically sensitive and challenging terrain; with a rich history, culture and religion. There was also the physical challenge of working at 12,000-14,000 feet [3,600-4,200 m] above the sea level. It remains one of the most enduring experiences of not just the book but also of my life. You meet all kinds of people. You step into a field, gather a handful of green and realise it is aromatic because it consists entirely of medicinal herbs. I remember standing in a small gorge and looking up, struck by the thought that over millennia, the river has carved its way through the rocks to flow from Tibet to Bangladesh. That is a long journey, and this has profoundly shaped my own thinking and understanding.
RG: Your journeys capture changes in climate along the river. What do these shifts mean for the river’s character, its ecosystems and its relationship with humans?
SH: Human interventions are altering the river across Tibet, Arunachal Pradesh, Assam and beyond. These include not just dams but also roads, bridges and widespread illegal sand mining taking place not just in the Brahmaputra, but also in the rivers that flow into it. Together, these activities are reshaping ecosystems in profound ways. In Assam, where I have travelled most extensively over many years, ordinary people are often unprepared for these changes. A farmer once told me, “Last year, the rains came late so I lost my crop. This year, they came early so I lost it again. How do we cope?”
For many young people, the only apparent way of adaptation is to leave. This is especially true for the river’s vulnerable island communities. The Brahmaputra has more than 2,000 islands, home to at least a couple of million people. Known as char chapori in Assamese, these communities are acutely vulnerable to not just the regular annual floods but also to prolonged dry periods and growing climate uncertainty. The conse-quences extend beyond to everyday life: how children go to school and how one gets access to health.
RG: China is building the Medog dam, set to be the world’s largest, at the Namcha Barwa Gorge on the great bend of the Brahmaputra. How do you view the project?
SH: The dam is a terrible idea. The project fails to account for the enormous impacts on water resources, people and ecosystems, many of which exist within the gorge itself, a place of remarkable natural beauty and ecological significance. I am sceptical of large dams in general. In Himalayan rivers, siltation occurs very rapidly. The life of a dam is diminished by the high level of erosion as rivers carry vast quantities of sediment.
The impacts downstream are also uncertain. Chinese authorities insist there will be none, but it is difficult to fathom how that can be the case. One fundamental aspect of a dam is that turbines require to be run by relatively clean water; they get damaged by rocks and sand in large quantities, making power generation unviable. Yet, water stripped of sediment, also loses the nutrients essential for ecosystems downstream. These fertile sediments are essential for fish species and river dolphins as well as for people whose livelihoods depend on fertile floodplains for agriculture.
RG: What does river-linking mean for the future of rivers?
SH: River interlinking goes against natural flows. Some interventions may be necessary, but there is a real risk in celebrating them or treating nature belligerently. Rivers need to run free. That is a fundamental right they have. Yet projects often rush in the name of corporate or urban benefit, paying little heed to the opinion of local people. Democracy, at its core, is about giving people that choice.
This article was originally published in the February 1-15, 2026 print edition of Down To Earth