A bustling city — Kolkata produces almost 750 million litres of wastewater and sewage every day. Yet, the city’s main area does not have a single sewage-treatment plant. So where does all of Kolkata’s waste go?
The answer is the East Kolkata Wetlands, the world’s only fully functional organic sewage management system.
What Is The East Kolkata Wetlands?
The East Kolkata Wetlands (EKW), designated a UNESCO World Heritage Site in 2017, is spread over 12500 hectares and includes the infamous Dhapa Dumping Ground. However, it is more than just that – it is a unique ecosystem that is famous all over the world as the largest natural recycling centre for solid waste and sewage.
For more than a hundred years, these wetlands have been an example of how to successfully utilize the vast amounts of waste that gets disposed of on a daily basis. The local communities living in the region make judicious use of the wastewater that flows through the arterial channels from the pumping stations located at different zones in the city to practice pisciculture and the cultivation of paddy and vegetables.
The East Kolkata Wetlands and Waste Recycling Region (EKWWRR) is made up of numerous intertidal marshes, bheris (wastewater treatment areas), sewage canals, vegetable and paddy farms, oxidation basins, and a dumping ground that collects the city’s ever-growing solid waste.
An architectural feat, this region has been sustained by the local communities that have been involved in the conservation of the fragile eco-zone. But as the city continues to grow, the East Kolkata Wetlands – neglected by the city and its inhabitants – has been under threat from rapid encroachments from all sides. The lack of appropriate awareness amongst the people in the city has only made it much easier to encroach on this zone.
A Brief History Of The Wetlands
Though the East Kolkata Wetlands were declared a Ramsar site in 2002, followed by the EKW Management Act in 2006, its history goes back to the 18th century when it was an area of intertidal marshes between the two rivers – Hooghly on the west and the now non-existent Bidyadhari river on the east.
Since then, the area has seen many changes in terms of the land use pattern. As the Bidyadhari started to dry out, the sewage outfall was redirected from the southeast to the eastern edge of the city, while the suburban township of Salt Lake was created by reclaiming land from the bheris on this side of the city.
The earliest example of using waste generated from the city for vegetable cultivation can be traced back to 1879 when Mr Bhabanath Sen designed a unique system of agriculture in the zone – he recommended using alternate rows of water bodies followed by subsequent highlands (which was constructed from layers of the garbage disposal).
A similar line of thought was employed for the generation of sewage-fed fisheries in the wetlands and the first wastewater fish pond was constructed in 1929. Much later in 1983, Dr Dhrubajyoti Ghosh – an engineer turned environmentalist – led the efforts to measure and map the entire wetland region. He named it the East Calcutta Wetlands. Involved in the conservation and protection of the zone since then, Dr Ghosh had been vocal about protecting this fragile ecosystem till the time of his death in 2018.
The Wetlands And The City It Serves
Situated on the fringe, the wetlands have for the longest time acted as the garbage bin of the city of Kolkata. However, it offers a case study of the appropriate utilization of sewage and solid waste. Put to use in one manner or the other, a majority of what is received in the EKW is redirected towards recycling and re-utilization amongst the community that resides and works in the region. The sewage water flows through pipelines to the saltwater meadows where they aid in the production of fresh fish.
The barren lands make way for growing edible vegetables that are then sold in the markets. A cheaper supply of edible food is made available in the city through the efforts of the communities in the wetland region. It also generates employment for the locals, who reside nearby.
Along with sewage and solid waste, in recent times, there have also been instances of industries in the region dumping their toxic effluents into the wetlands. These effluents contain hazardous materials like sulphate and nitrate that, in turn, pose a threat to the unique biodiversity of the East Kolkata Wetlands. Two other problems plaguing the zone are–urban encroachments from land sharks and siltation of the saltwater bheris.
As the city’s population and real estate sales boom there has been blatant ignorance of the laws that prohibit urban developmental projects in the zone. The lack of adherence to appropriate rules has only been made worse by the willful ignorance of the governmental agencies responsible for the upkeep of the wetlands.
In 2017, it came to notice that a governmental proposal for a flyover through the East Kolkata Wetlands was quietly passed and was in an advanced stage of planning. What’s more, it was introduced by then-Mayor Sovan Chatterjee, who was not only the chairman of the East Kolkata Wetlands Management Authority but also the environment minister in the state.
The motive – to reduce commute time to the airport situated on the northern flank of the city. Environmentalists involved in the upkeep of the region protested the decision and a subsequent PIL, filed by the NGO People United for Better Living in Calcutta (PUBLIC) led to the project being stalled by the Supreme Court.
While the government till now had made only meagre efforts to preserve this Ramsar site, on World Environment Day this year, the government has pledged more resources and action to protect the region. A Rs. 120 crore action plan has been chalked out that is to be executed over the next five years for the conservation of the ecological pocket.
Some of the action items on its agenda is said to include putting in place measures to stop encroachments, preventing contamination of the water that flows to the region from tanneries near the wetlands, and creating more awareness of the East Kolkata Wetlands and Waste Recycling Region.
Given the unique biodiversity of the wetlands, it is home to a diverse range of flora and fauna. It is also home to the thousands of people who have been involved in the upkeep of the zone. However, the East Kolkata Wetlands are now under threat from various different sources. Two back-to-back climate-change-induced cyclones have ravaged the region significantly. On the other side, land encroachments and illegal dumping of effluents only add to the problems in the ecologically fragile pocket.
What’s needed is more awareness about the unique properties that make this zone one-of-a-kind and a greater interest in the issues plaguing the wetlands by the inhabitants who in one way or the other benefit from this region.