East Kolkata Wetlands: The world's largest organic sewage management system

Last Modified: Tue Apr 04 2017 12:48:13 GMT+0530 (India Standard Time)
  • 12,500 hectares
    Spread of the East Kolkata Wetlands site. World-renowned as a model of a multiple use wetland, the site’s resource recovery systems have been developed by local people through the ages. The wetland not only treats the city’s sewage but the treated water is utilised for pisciculture and agriculture, thus saving the city of Kolkata from the costs of constructing and maintaining waste water treatment plants.
  • 1,000 million litres
    of sewage which enters the East Kolkata Wetlands (EKW) each day. In 2016, the cost of setting up a Sewage Treatment Plant to handle similar quantities of sewage in Malad, Mumbai was estimated to be Rs. 4,500 crore.
  • 254
    fish ponds - or bheris as they are known locally - feed off the incoming sewage water that undergoes a process called bioremediation. Organic matter from the sewage along with sunlight cause the growth of planktons, which in turn is used to feed the fish and in the process the water is purified. Purified water is then utilised to grow vegetables in adjoining fields. (Click Engage and Interact to watch video).
  • 10,500 tonnes
    of fish produced in the bheris each year - that meets close to 33% of the city's needs.
  • 150 tonnes
    of fresh vegetables produced each year - approximately 40% - 50% of the city's requirement.
  • 50,000
    Number of people who's livelihoods depend directly on the wetland and a further 50,000 indirectly supported.
  • 2002
    East Kolkata Wetland declared as a Ramsar site.
  • $38.54 million
    estimated annual economic value of the wetland.