Sometime in the early 1980s, West Bengal’s finance minister wanted to find out how to gainfully use Kolkata’s sewage. Dhrubajyoti Ghosh, an engineer in the state’s planning board, was assigned the task. He was to travel across the country and prepare a report within a year. He got his ticket to visit India’s first sewage treatment plant at Dadar, Mumbai. Then came a moment of introspection. It occurred to me that they might ask me how Kolkata handles its sewage, Ghosh later recounted, I didn’t know. He searched high and low and found nothing. It seemed nobody knew what the city did with its sewage. So Ghosh did what officers aren’t encouraged to do in government policy: He went for a walk. He ambled along the 28-km channel that carried the city’s sewage eastwards, along the slope, to where the salt marshes once stood. Here, he saw shallow ponds that turned the city’s sewage into algae. Then, the algae-rich water was let into nurseries, to be eaten by fish, that was then sold in the city. A marvel of recycling, of turning waste into food. Shortly after, Ghosh wrote an account of what he’d seen and sent it to Richard Meier, a famous American ecologist. Meier was delighted; he wrote back to tell Ghosh that if he invested five years in the wetlands of east Kolkata, he’ll make history. Ghosh replied he was ready to invest 10. He ended up dedicating most of his working life to the wetlands, right up to his death at the age of 71 in a Kolkata hospital last Friday, February 16. That the East Kolkata Wetlands (EKW) exist today, spread over thousands of acres, owes to Ghosh’s untiring efforts. The fisherfolk here have grown fish in Kolkata’s sewage for the past 80 years, at least. Their craft has been fine-tuned over generations. Both the scale and nature of the operation has no parallel in the world. The wetlands, often called the city’s kidneys, treat its sewage and garbage for free, provide employment to thousands, and generate cheap food. Not to mention preventing floods, absorbing Kolkata’s runoff during the monsoon (are you listening Chennai, Mumbai, Bengaluru?). Another country might have been proud. Another country might have learned from Ghosh’s work, and found inspiration in EKW’s fisherfolk to clean its rivers and lakes saturated with untreated sewage. Not India. But for Ghosh, who retired in 2004 as West Bengal’s chief environment officer, land sharks with political connections would have developed the wetlands a long time ago. Perhaps nobody imagined Ghosh’s tenacity and the scope of his scholarship. Through years of effort, he documented the wetlands and its fisherfolk, surveyed the land, created a strong case for their protection, all in a way only a government official could have done. In 2002, the Ramsar Convention on Wetlands extended its protection to the EKW. Now, both the Union and state governments are bound by an international treaty to protect it from real estate developers. This made Ghosh unpopular in some government circles. He had to take early retirement. As an official, he worked from inside the government to protect the EKW. After his retirement, he became a full-time activist and a scholar of ecology. He started writing about the EKW widely. He brought out books based on his studies. He collaborated with numerous organisations and individuals, inspiring them, mentoring researchers, all the while keeping alive his relationship with the fisherfolk of the EKW. Among them, he was not a scholar who had come from outside to study them as his subject material. He was a friend, a go-to man, agony aunt, and a warm avuncular presence. There was a sweet irony in Ghosh’s ecological interest in sewage. Born in 1947, Ghosh began his career in the late 1960s as a junior engineer, making sewers for a monthly salary of Rs 100. He dabbled in the Naxal brand of Maoist politics, but was disillusioned soon. A book he read during a train journey mentioned, in the footnotes, an ecological study of West Bengal villages. He fell in love with the idea of ecology. He got in touch with Meiers, then a famous ecologist in the University of California in Berkely. Meiers became the external supervisor of Ghosh’s PhD from the University of Kolkata. He was still working as an assistant engineer in the city’s water and sanitation authority. The young engineer so impressed Meier that he would come to India on his own steam to guide Ghosh, later becoming his mentor. Our governments spend crores of rupees in contractor-heavy programmes to clean rivers. Ghosh’s life and work showed that the solutions are cheaper than we imagine. They lie in ordinary people. All that is needed is leaders and officials who are ready to go out for a walk. With an open mind, with a warm heart, with the commitment of sound scholarship.