The Convention on Wetlands, signed in Ramsar, Iran, in 1971,  is an intergovernmental treaty which provides the framework for national action  and international cooperation for the conservation and wise use of wetlands and  their resources. There are presently 158 Contracting Parties to the Convention,  with 1831 wetland sites, totaling 170 million hectares, designated for  inclusion in the Ramsar List of Wetlands of International Importance.

East Calcutta Wetlands. 19/08/02. West Bengal.  12,500 ha. 22°27’N 088°27’E. World-renowned as a model of a multiple use  wetland, the site’s resource recovery systems, developed by local people  through the ages, have saved the city of Calcutta from the costs of  constructing and maintaining waste water treatment plants. The wetland forms an  urban facility for treating the city’s waste water and utilizing the treated  water for pisciculture and agriculture, through the recovery of nutrients in an  efficient manner – the water flows through fish ponds covering about 4,000 ha,  and the ponds act as solar reactors and complete most of their bio-chemical  reactions with the help of solar energy. Thus the system is described as  “one of the rare examples of environmental protection and development  management where a complex ecological process has been adopted by the local  farmers for mastering the resource recovery activities” (RIS). The wetland  provides about 150 tons of fresh vegetables daily, as well as some 10,500 tons  of table fish per year, the latter providing livelihoods for about 50,000  people directly and as many again indirectly. The fish ponds are mostly  operated by worker cooperatives, in some cases in legal associations and in  others in cooperative groups whose tenurial rights are under legal challenge. A  potential threat is seen in recent unauthorized use of the waste water outfall  channels by industries which add metals to the canal sludge and threaten the  edible quality of the fish and vegetables. Ramsar site no. 1208.

For  detail information about RAMSAR Convention go to the official website of RAMSAR: www.ramsar.org