The East Kolkata Wetlands (EKW) are unique yet complex system of natural and human-made wetlands in West Bengal. The wetlands cover 125 sq km comprising of salt marshes, salt meadows, sewage farms and settling ponds. They are used to treat Kolkata’s sewage, and the nutrients contained in the waste water sustain fish farms and agriculture.
Devised by local fishermen and farmers, these wetlands served, in effect, as the largest natural sewage treatment plant (STP) for the city. And using the purification capacity of wetlands, Kolkata by transforming nearly one-third of the city’s sewage into a rich harvest of fish and fresh vegetables daily, has pioneered an environment-friendly system of sewage disposal. Because of this, the EKW were designated a “wetland of international importance” under the Ramsar Convention on August 19, 2002. https://en.wikipedia.org/wiki/East_Kolkata_Wetlands
However for past many years, these wetlands are under threat due to exponential expansion of real-estate projects. Recently illegal landfills are on the rise and unprecedented land development and urbanization have been creating concerns about the impact on EKW environment. 2017 has seen the situation turning only worse for EKW.