Across India and around the world, wetlands are increasingly being recognised as vital natural infrastructure. They help cities manage floods, recharge groundwater, store carbon and support biodiversity. But rapid urban expansion, encroachments and pollution are putting many of these ecosystems at risk, and the East Kolkata Wetlands (EKW) have now become a striking example of that struggle.
The wetlands have returned to the spotlight after residents called for a balance between ecological protection and the basic needs of long-settled villages and farming communities. The issue has also drawn attention after the Calcutta High Court criticised the state government and the Kolkata Municipal Corporation for failing to remove illegal constructions from the Ramsar site despite repeated orders. A fire at a warehouse in Nazirabad on January 26, which killed several people, further intensified concern over development inside the protected area.
What are the East Kolkata Wetlands?
The East Kolkata Wetlands are one of the world’s most unusual urban wetland systems and are often described as the largest natural wastewater recycling system on the planet. They were designated as Ramsar site in 2002.
Spread over about 12,500 hectares on Kolkata’s eastern edge, the wetlands absorb rainwater, recharge groundwater and support thousands of livelihoods. They also help protect the city from floods by naturally treating sewage and storing excess water.
Who mapped the East Kolkata Wetlands?
Ecologist and engineer Dhrubojyoti Ghosh mapped the wetlands over nearly three years. His work showed how Kolkata’s wastewater could be turned into an ecological and economic resource.
Why are the East Kolkata Wetlands called the kidneys of Kolkata?
They are called Kolkata’s “natural kidneys” because they filter and purify wastewater before it returns to the environment, much like human kidneys remove waste from the body.
How do the East Kolkata Wetlands benefit everyday life?
The wetlands include around 260 sewage-fed fish ponds, salt marshes and settling ponds. Every day, they naturally recycle nearly 910 million litres of untreated sewage through biological processes.
This reduces the need for costly treatment plants and also helps control floods, droughts and heatwaves. The wetlands support fisheries, store carbon and provide livelihoods to thousands of people.
Did the Nazirabad godown where 27 people died in a fire allegedly come up on EKW land?
Yes, the fire at the Nazirabad godown in Anandapur on January 26, which killed 27 people, mostly daily wage workers, allegedly took place on EKW land. The incident renewed concerns about illegal construction in the wetlands.
It also highlighted the ongoing violation of a 1992 Calcutta High Court order prohibiting land conversion in the protected area.
What do environmental experts say?
Experts blame administrative and political apathy, weak conservation planning, unchecked urbanisation and encroachments. A recent study found that more than half the wetlands have changed in character over the past two decades, while encroachments have risen by about 9%.
What is the economic value of wetlands?
Wetlands are among the world’s most productive ecosystems and provide services worth billions of dollars each year through flood control, water purification, fisheries, agriculture and climate regulation.
In India, at least 6% of the population depends directly on wetlands for their livelihoods. Yet the Union Environment Ministry says only 102 of the country’s nearly two lakh wetlands have been formally notified, leaving around 99% without legal protection. Rajasthan, Goa and Uttar Pradesh are the only states with notified wetlands.
How are livelihoods affected by the EKW?
Around 1.3 lakh people depend on the East Kolkata Wetlands. Fish farmers say declining sewage inflows have reduced fish production and forced many to sell their ponds.
Some blame changes in water management by the Kolkata Municipal Corporation. A study by the Central Inland Fisheries Research Institute also found a steady decline in fish production over the past 25 years.
What are the main demands of residents living in the habitable zones of the wetlands?
Residents want scientific zoning and fresh satellite-based demarcation of the wetlands so that environmental protection does not override the rights of long-settled communities.
They have asked for regional zoning under the Wetlands Rules, 2017, and say restrictions on repairs, sanitation and basic infrastructure have hurt Scheduled Caste and Scheduled Tribe families. They have also urged the state to consult all stakeholders.
Why did the Calcutta High Court pull up the Bengal government and the EKWMA?
In February, the Calcutta High Court expressed frustration over the state’s failure to remove more than 500 illegal constructions despite repeated directions.
Justice Amrita Sinha said the court was even considering deploying paramilitary forces and questioned why the statutory authority responsible for protecting the wetlands had not acted.
Is the EKW area shrinking?
Yes. Despite legal protection since 2006, the wetlands have reportedly shrunk from about 65 sq km to 41 sq km over the past three decades due to illegal land conversion, urban expansion, and infrastructure development.
Studies suggest that more than half the wetland area has undergone ecological change in the last two decades, while environmental groups estimate that nearly a quarter was lost between 1991 and 2001, with further losses since then.
What needs to be done to protect the East Kolkata Wetlands?
Environmentalists want the West Bengal government to treat the wetlands as an ecological and public policy priority. They have called for a high-powered task force, scientific mapping, satellite-based demarcation, time-bound removal of illegal structures and restoration of degraded water bodies.
They also want stronger coordination among the East Kolkata Wetlands Management Authority, the Kolkata Municipal Corporation and other agencies. At the same time, they stress that conservation must be balanced with the legitimate needs of long-settled residents through scientific zoning and planned development.