The real-estate aggression on waterbodies has prompted the Calcutta Metropolitan Planning Committee (CMPC) to ask the civic authorities to protect and preserve all wetlands in the city.

A survey by the Institute of Wetland Management and Ecological Design (IWMED) has pegged the total number of waterbodies in Calcutta at 1,931. The survey lays special emphasis on the preservation of the East Calcutta Wetlands, which has been notified as a Ramsar site.

The CMPC discussed at its meeting last week the five-year development plan, and decided that no part of the East Calcutta Wetlands would be allowed to be filled under any circumstance.

The committee also decided that every development proposal relating to the wetlands has to be approved by the environment department.

Mayor Subrata Mukherjee said on Thursday that the definition of wetlands, as adopted at the 1971 Ramsar convention (in Iran), has been accepted by India. Accordingly, 19 wetlands in the country, including the one in east Calcutta, have been incorporated into the Ramsar list.

The IWMED report states that the Calcutta Metropolitan Area, spread across 41 municipal bodies, has over 10,000 waterbodies, each measuring not less than five cottahs.

However, the wetlands taken together barely constitute six per cent of the total metropolitan area.

Mayor Mukherjee said the Calcutta Municipal Corporation would carry out a ?ground verification? of the 12,500-hectare East Calcutta Wetlands, to be followed by a detailed mapping of the micro-level land-use pattern of the region.

The land-use pattern will be recorded under five major heads: wetland, agriculture land, garbage farming, urban and rural settlements and added peripheral sectors.

The objective of the survey, Mukherjee explained, is to maintain the ?integrity of the system? and promote its proper utilisation.

The CMPC has highlighted eight basic purposes that waterbodies serve:

Recreational activities in congested areas

Sources of water for a large number of people, including fire-fighters

Aquaculture or farming

Flood-control basin in areas prone to waterlogging

Domestic waste-water receptors

Habitat for waterfowl

Resource recovery from waste-water

Source of various scientific information.