Harvard professor and author Sunil Amrith speaks to Rishita Roy Chowdhury about his latest book, Unruly Waters, which looks at the role water has played in South Asian history.

Sunil Amrith is an acclaimed historian and professor of South Asian Studies at Harvard University. He won the MacArthur “Genius” Grant in 2017. His latest book, Unruly Waters: How Mountain Rivers And Monsoons Have Shaped South Asia’s History, explores a continent’s history in connection to its rivers, seas and rains.

In this exclusive interview with Guardian 20 Amrith talks about his book, the damaging effects of water politics and our looming climate crisis.

Q. What was the vision behind putting together a historical account of South Asia as shaped by its waters, as you do in your new book, Unruly Waters?

A. The vision emerged slowly, pieced together from many, initially disparate, experiences. Working on my previous book, Crossing the Bay of Bengal, I had spent a lot of time in coastal Tamil Nadu, researching the small port cities from which many migrants left for Southeast Asia in the 19th century—Nagapattinam, Cuddalore, Nagore, Karaikal, places like that. It became clear to me that coastal regions in India face a combination of threats: sea level rise, more intensive cyclones, coastal erosion, pollution, and reckless coastal development. At the same time, travelling further inland, I could see the scars of prolonged drought wherever I went. Farmers and fishers told me that they could no longer “trust” the monsoon. Water’s excess and its absence were everywhere on people’s minds.

These observations cohered into something more tangible as a result of the inspiration I drew from scholarship I was reading at the time: China historian Kenneth Pomeranz’s vital 2009 article on what he called the “great Himalayan watershed”; Annu Jalais’s book on the Sundarbans; my Harvard colleague Diana Eck’s book on India’s sacred rivers; the classic work of Mike Davis on the water history of California. I was also reading lots of fiction and poetry that made me think about water in the broadest sense, from Amitav Ghosh’s The Hungry Tide to Alice Oswald’s beautiful poem, “Dart”, which tries to tell the story of the Dart river (in Devon, England) through multiple voices.

Q. Tell us about the symbolism behind the word “unruly”, which appears in your book’s title.

A. The image of “unruliness” encapsulates one of the book’s key arguments: despite concerted and even desperate attempts to control it, despite the apparent success of many of those attempts, water transcends human schemes and human borders. Climate change illustrates the power of human activity to shape the climate, yes—but it also reminds us of the power of nature, and the fragility of every scheme to conquer it.

Q. In your view, how have the monsoons changed in India? What are the factors leading to such changes?

A. What I say in the book about how the monsoons are changing isn’t based on my own primary research—I’m a historian and not a climate scientist. I draw my knowledge of changes in the monsoon from reading the very important research currently being done by climate scientists and tropical meteorologists both within and outside India; those works are cited in the book for readers who wish to delve more deeply into the science.

What seems apparent is that the monsoons have become more erratic and more prone to extremes of wet and dry over the last few decades. There are many contributing factors at work—one is planetary warming. But there are also regional drivers of the change. Aerosols and changes in land use have both been pinpointed as altering the thermal and pressure contrasts that drive monsoon circulation. What is most interesting to me, as a historian, is that these changes in the monsoon in some ways reflect the particular trajectory of Indian economic history over the past 50 years or more, including the deep inequalities in access to energy and types of energy use that continue to characterise India.

Q. How did the reshaping of India’s hydraulic infrastructure take place during the colonial era? Does it still impact our political independence and economic development?

A. The British were certainly not the first rulers of India to try to reshape the hydraulic landscape. Different regions of India had very sophisticated systems of irrigation and water control from the earliest times: from the tank irrigation of the Deccan and the south to the stepwells of Gujarat and Rajasthan, from the anicuts of the southern rivers to the large waterworks of Mughal-era north India. Having said this, India’s pre-modern history of water control was never as elaborate or as centralised as China’s. In earlier times the benefits of hydraulic infrastructure resided at the local, or at most the regional, level. In this sense, perhaps the most far-reaching change that British imperial engineering brought was its spatial expanse—in the imagination of British engineers and administrators and investors, the irrigation of a particular district of the Godavari delta or the Gangetic plain would have repercussions across the globe, as more and more of the products of India’s soil found their buyers in the markets of London and Liverpool, Hamburg and New York. This legacy continues to impact economic development in India and elsewhere in Asia.

Q. How extensive was your research for this project?

A. It was very extensive! I was glad finally to finish it, having lived with this project through many life transitions. To tell a story on this scale, I had to delve into many different kinds of archives and materials. I spent a lot of time looking at the archives of the India Meteorological Department, going back to its foundation in the 1870s. I immersed myself in official discussions on water and irrigation. I also spent a lot of time travelling, talking to people—meteorologists, fishers, cultivators, urban planners. Visual repositories were important too: maps and photographs. The cinema, too; in one of the chapters of the book, I point out how central the theme of water is to many of the classics of Hindi cinema, including, of course, Mother India. I then had to read as much as I could of contemporary climate research—and to make sure I understood it, given that I’m not trained as a scientist, I spent time talking to colleagues in that field.

Q. Your book explores how climate change and shifts in monsoon patterns could affect the availability of water in the future. Tell us more about that.

A. The situation now appears even more worrying than I indicated when I finished writing Unruly Watersin the middle of 2018. The recent Hindu Kush Himalaya Assessment suggests that, even with a drastic reduction in carbon emissions, a third of the Himalayan glaciers are doomed to melt by the end of this century; without a reduction in emissions, that grows to two-thirds. The livelihoods of well over a billion people are directly at risk from this. Most studies predict that, after an initial period of augmented river flow due to glacial melt, the rivers will begin to dry up for part of the year from 2050 or 2060. To this we must also add changes in the monsoon’s patterns—which, as I mentioned earlier, appear to be growing more erratic. This will pose a real challenge to cropping patterns in India and beyond—especially in a context where groundwater reserves are critically depleted.

Q. Your book establishes that “water is politics”. Could you elaborate?

A. Water is so essential to life, to food security, to economic prosperity, that every attempt to control or to capture it is inherently political. The control of water bestows power on some groups and denies it to others. Water is both an index and a driver of inequality, not only in India but everywhere. Access to clean water is as good an indicator of any of the fault lines of inequality and exclusion in a society. The ability to monopolise water deepens inequalities—as we see in rural India with the rise of “water lords” who exploit groundwater to the exclusion of others’ needs. One of the arguments in Unruly Watersis that the control of water has long been central to many competing ideas of freedom in India and Asia, as “the” basic material precondition that underpinned many dreams of prosperity and autonomy.

Q. In an age of climate change, how can we mitigate environmental damage? And what does the future hold for humanity?

A. Collective action has been, and remains, vital. India is fortunate in this regard, in the depth and sophistication of its environmental movement. There is a deep wellspring of ideas to draw upon—Gandhian ideas, ideas rooted in India’s local and regional traditions, broader ideas about environmental justice forged through the interaction of activists from across the Global South. Having said that, the hostility towards environmentalists shown by successive Indian governments, and most especially by the current government, is dismaying.

I think activism around environmental protection must appeal to the ways in which environmental damage threatens us all with a profound sense of loss, in our most quotidian and intimate lives—a loss of the landscapes we love and depend on; a loss of language, as the names we have for things no longer accurately describe them; a loss of livelihood for those who depend most directly on the rains, the rivers and the oceans; a loss of our bearings, as the climate that has shaped our culture in profound ways begins to shift.

Given that many of the water-related crises transcend national borders, it is especially important to forge alliances on a wider regional level. Without that, state policies towards the control and exploitation of water, for instance, will remain a zero-sum game.