Kolkata has got rich wetlands spread considerably towards its eastern edge. Kolkata is sloping eastwards. Kolkata's drainage system is releasing the waste water to these water bodies or otherwise most of the waste water is guided towards these scattered wetlands. The escaping water, which is gradually being cleaned up on its course naturally or by other means, used for fish firming & vegetation. The remaining water, if any was once being released through the river Bidhyadhari and its various tributaries..

Considerable number of people is engaged in this wastewater culture naturally or otherwise purifying the wastewater and then fish farming and vegetation in the adjacent stretch of lands. The wet lands supply appreciable amount of fishes and vegetables daily to cater for Kolkatas requirement, commonly called as Dhapa.

The wetland areas are no doubt engaged in keeping balance of nature of Kolkata by absorbing wastewater etc. and in return giving an ecosystem with wetlands and green, also providing essential fish and vegetables for Kolkata and adjoining areas.

The wetlands are now being threatened with building activities. A considerable stretch of wetland is gradually being filled up to make way for buildings, other industrial activities and habitations therein. Though there is standing law to protect wetlands and restrictions to fill them up, it is evident that law is not properly taking its course.

When the city of Kolkata is gradually being expanded, these wetlands are gradually being decreased. These wetlands should be safeguarded. The authorities may look into the possibilities of extending these wetlands or forming new wetlands eastwards adjacent to the surroundings. If policymakers and authorities fail to safeguard the wetlands it will be disastrous.