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East Kolkata Wetlands

Rainwater run-off and water discarded after being used for a wide range of human activities; every city of the world must find a way of dealing with its wastewater. But is this water a useful resource or a public health hazard? Should it be treated in conventional and costly treatment plants or are there ecological wastewater treatment schemes that recycle the water effectively and productively without hazard to those who are using it or who may ultimately consume what it has produced? One of the largest systems in the world for making use of this source of 'natural' city water is on the eastern edge of Kolkata (Calcutta), India. Here research is attempting to show municipal authorities, NGOs, development agencies, farmers, fishers and others directly or indirectly connected with the Wetlands, just how valuable these city waters are and what could be done to improve their use. The lessons learned here could be of interest to city authorities elsewhere.

Peri-urban fish market. Kolkata.
Credit: Stuart Bunting

The East Kolkata Wetlands have an interesting hydrological history. The area had been a brackish water lagoon swamp but as fresh drainage water came out of Kolkata it became suitable for raising fish. Local farmers stocked some of the ponds and then dug more. Currently, there are 300 or so large fish farms and ponds cover a total area of 3,500 hectares, some individual ponds extend to 70ha. Landlords, many of them absentee, let the majority of ponds to commercial managers, some others are managed by the government and some have been given to fishermen's groups and cooperatives. Vegetable production is a household activity with people renting small plots or sub-letting smaller plots for their own household sustenance and income. Apart from those people actually raising fish (about 8,000) or growing vegetables, there are porters, auctioneers, traders, retailers and people raising fish seed, making nets, maintaining drainage canals and reinforcing the banks. A great many people, many of them poor, depend on the Wetlands for their livelihoods. Many more, in Kolkata city, depend on the fish and vegetables produced; 13,000 tonnes of fish are produced annually in ponds managed for wastewater aquaculture and 150 tonnes vegetables per day are harvested from small-scale horticultural plots irrigated with wastewater. But there are a number of problems. Unless those are recognized and dealt with, the whole system, as it operates at the moment, could cease to function. Many would suffer.

The first problem is one of encroaching urban development. Rumours that the land, although officially protected by legislation, is subject to development speculation mean that people are wary of wasting resources on maintaining or possibly enhancing the system. Secondly, there is a major problem with silt. Some fishponds, that were initially six feet deep, have silted up to within two feet of the surface, cutting potential fish production by two-thirds. The dredging and transport that would be required to clean out such a big area of ponds is a huge undertaking, even given that the silt could be used with advantage for landfill to the north of the region where a new township is planned.

There is third problem that will also be widely recognized. The productivity and problems of the region have been known for many years. Research, mostly concentrating on the technical and financial aspects of pond management, has continued throughout. However, despite useful findings, little has changed. This is probably because those findings have never been formulated into a management plan that took proper account of the whole complexity of the system and the livelihoods of the people involved. Well aware of this, the present research team*, which receives funding from the UK Government's Department for International Development, has been determined not to fall into the same trap.

Great efforts have been made to work with farmers and fishers, with representatives of development agencies, NGOs, local government officials, farm managers etc., and with senior representatives of relevant government agencies. Existing knowledge has been consolidated rather than re-researched and the concentration has been focused on developing practical management plans that can be implemented by local authorities or development agencies. These have been widely disseminated and the result is a much wider and better understanding of the system and the opportunities that exist for improving production while mitigating environmental degradation and reducing health risks.

The East Kolkata Wetlands have been so important, both in terms of providing livelihoods and products as well as in making use of a natural source of water, that no-one wants to see the system collapse. Stuart Bunting, manager of the research project at the University of Stirling, is convinced that the strong local and international support for the Wetlands, and the people who depend on them, will deter developers. If the major technical problems can be overcome, the future looks good.

*The research team consists of members from both local and international organizations; from the Institute of Wetland Management and Ecological Design and from the Department of Fisheries in West Bengal and from the University of Stirling (Scotland), the Henry Doubleday Research Association (UK) and from the Asian Institute of Technology. For further information and to access recent outputs please visit the project website
This publication is an output from a project funded by the UK Department for International Development (DFID) for the benefit of developing countries. The views expressed are not necessarily those of DFID.

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