Unsung Guardians: The Vital Wetlands of Kolkata

Photo Story Published : Aug 31, 2022 Updated : Sep 30, 2023
The wetlands that surround Kolkata support great biodiversity and provide it with numerous ecological benefits (including acting as an organic sewage treatment plant for the city’s wastewater)
Unsung Guardians: The Vital Wetlands of Kolkata
The wetlands that surround Kolkata support great biodiversity and provide it with numerous ecological benefits (including acting as an organic sewage treatment plant for the city’s wastewater)

The East Kolkata Wetlands (EKW), a 125-sq-km naturally occurring wetland, lies on the eastern fringes of the Kolkata Metropolitan Region. “These waterbodies are important. They impact the microclimate of the local area and act as carbon sinks, says Dr Mohit Ray, an environmental activist who has campaigned extensively to save Kolkata’s waterbodies. By absorbing atmospheric carbon emissions, they reduce the greenhouse effect and human-induced climate change.

Besides the EKW, the other important waterbodies in and around the city are the Rajarhat wetlands, Santragachi Jheel, and Dankuni wetlands. While Rajarhat, an extension of the EKW, lies within the city limits, the other two are a short drive away. Santragachi Jheel is about 30 kilometres west of Rajarhat in the Howrah district. Dankuni, an extensive marshland interspersed with continuous patches of reed beds and vegetation, is 20 kilometres north of Santragachi in the Hooghly district.

Among all these wetlands, only the EKW and Santragachi Jheel are directly protected by law. However, the West Bengal Inland Fisheries Act, 1984 (amended in 1993) states that if any waterbody can be used for pisciculture and aquaculture, then it must be used for that purpose only. Additionally, “the West Bengal Land Reforms Act says that if you fill up any waterbody (with rock, debris, or other solid materials), then you have to create a compensatory waterbody. These laws help protect waterbodies at the state level,” says Meghna Banerjee, lawyer and co-founder of the Human & Environment Alliance League (HEAL).

Protecting these wetlands is important because they provide Kolkata with numerous ecological benefits and support diverse populations of insects, birds, and animals. “Not only do wetlands support waterfowl like ducks, but also birds that breed in the reeds and grasses, like munias and buntings,” says Sujan Chatterjee, secretary of Birdwatchers’ Society, who also leads the East India Birding tour company. 

Central Kolkata is bowl-shaped, with the Hooghly River flowing on its western side and the city’s natural topographical slope tilting towards the east. All excess waste and rainwater from the city drain out towards the EKW, which acts as a natural outlet. “EKW works as a safety wall for Kolkata city against flooding,” says Ray.
Cover photo: An aerial image of Rajarhat wetlands.
In 2002, the EKW was declared a Ramsar site, thanks to the efforts of Dhrubajyoti Ghosh, a civil engineer who has dedicated four decades to conserving these wetlands. Fifteen years later, the Ramsar Convention declared it “one of the two natural resources of wastewater treatment areas in the world” (the other is in Uganda). The EKW is often called the “kidneys of the city” since it naturally cleans out the wastewater generated by the city. The city produces an estimated 900 million litres of sewage daily. Underground sewers take this sewage to pumping stations, push it into open channels and canals, and further to fishponds. Here it rests until it breaks down organically into recycled water (used in paddy fields), algae, and plankton (used as fish fodder). The remaining organic waste is used to grow vegetables on a nearby hillock. 
The Rajarhat wetlands were not originally wetlands. Farmers owned these rice fields and sold them to private companies for industrial, residential, or commercial uses. In some barren plots, water accumulated over the years—turning them into waterbodies that harbour a healthy population of birds, dragonflies, and damselflies. 
Santragachi Jheel lies an hour’s drive from Rajarhat wetlands. Sandwiched between Santragachi railway station, residential colonies, and factories, this lake is protected not only by law but also by the people around it. The South Eastern Railway and the forest department own and maintain this waterbody. Residents help keep it free of pollution and make it a conducive environment for visiting migratory birds. 
The unique area around Santragachi Jheel hosts about 8,000 birds every winter. These include cormorants, gadwalls, pintails, shovelers in small numbers, and large flocks of lesser whistling ducks (Dendrocygna javanica). “It is a tiny place, and the ducks feel very safe. Even people without binoculars and cameras can see these birds at very close quarters,” says Chatterjee. 

Travelling 30 minutes north of Santragachi Jheel, the vast contiguous stretches of Dankuni wetlands were, until recently, not legally protected. “During our inspection and visits, in addition to rampant encroachment of the Dankuni wetland complex, our team came across numerous bird trapping nets. We did a local campaign and worked with the forest department to curb poaching and hunting here,” says Banerjee.

But encroachment remains Dankuni’s main challenge. “We have seen thousands of dumpsters filling up these wetlands. A carcass of the golden monitor lizard (Varanus flavescens), a species protected under Schedule I, Wildlife Protection Act, 1972, was crushed by a dumper truck here,” says Banerjee. These wetlands were being converted for the construction of factories and real estate at a tremendous pace. People United for Better Living in Calcutta (PUBLIC) filed a lawsuit to stop the illegal reclamation of these wetlands, and the court directed a government-appointed committee to protect the Dankuni wetlands. But PUBLIC is not satisfied with the working of this committee. It involved the National Green Tribunal (NGT), which has granted interim protection to these wetlands and placed an embargo on filling activities. The NGT also directed the District Magistrate and the Superintendent of Police of Hooghly district to prevent any reclamation of waterbodies in the area identified by the petitioners. In its final order of May 2022, the NGT has granted protection to all wetlands in the state, having an area of over 2.25 hectares, including Dankuni wetland.

Since the covid pandemic, there has been rampant encroachment on Kolkata’s wetlands. The EKW has been an easy victim of real estate companies illegally filling ponds and constructing buildings. In Rajarhat, canals have been filled up to allow access to parking areas for high-rise buildings. It is only a matter of time before this water canal (seen in the photo) in Rajarhat wetlands is filled, completing the connecting concrete road we can see. 


About the contributors

Amrita Das

Amrita Das

is the photo editor at Roundglass Sustain. When not at work, she invests her time travelling and hiking, in creative pursuits, reading and learning a new skill.
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Dhritiman Mukherjee

Dhritiman Mukherjee

is one of India's most prolific wildlife and conservation photographers. His work has been featured in leading publications. He is also a RoundGlass Ambassador, and an RBS Earth Hero awardee.
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