Understanding the socio-ecological impact of urbanization in the transformation of lakes and wetlands - a case studu of east Kolkata wetlands, West Bengal

Urban commons including wetlands constitute important socio-ecological systems providing valuable ecosystem services. However, unplanned rapid urbanization has resulted in largescale decline and transformation of commons, adversely affecting the traditional and vulnerable users. East Kolkata Wetlands (EKW), a network of natural and manmade wetlands, constitutes an important but neglected ecosystem of Kolkata on its eastern fringe. Traditionally maintained by the conventional scientific wisdom of the urban poor, EKW provides a range of valuable ecosystem services. Often considered as the kidneys of Kolkata, the dual benefits of natural sewage treatment of Kolkata, and wastewater fed aquaculture, thereby ensuring livelihood of thousands, makes EKW indeed a unique system. Rapid urban sprawl, constant pressure from real estate have brought about significant changes in the system, its use and management leading to large-scale shrinkage over the years thereby threatening its ecosystem services. In the process of such transformation, the study examines the perceptions of different stakeholders of EKW over the value of wetland, their response to such change and its impact on human-water resource relationship

A new imagination for waste and water in India’s peri-urban interface

Cities are often seen as incubators for enterprise and innovation. However, in this urbanization era, we seem to suffer from a lack of imagination on how to handle the many environmental problems associated with expanding cities. This is especially true in the case of the peri-urban interface (PUI), a geographical and conceptual landscape with which the city core often has a contentious relationship. In this chapter, we look at the complex linkages between water and waste in the PUIs of two metropolitan cities: Bengaluru and Kolkata. We look at two water systems: Kannuru lake in Bengaluru and Kolkata’s wetlands. Kannuru is a freshwater lake that supported traditional livelihoods and subsistence use by local communities, while Kolkata’s peri-urban wetlands not only served as the city’s natural sewage treatment plant but also enabled agriculture and aquaculture. Urbanization has adversely impacted both these water systems. Kannuru lake is threatened by a landfill on its periphery, while sewage-based farming and fisheries in Kolkata’s wetlands have been impacted by changes in land use and composition of sewage. We unravel the complexity in the waste-water relationship, where waste is seen as a pollutant in one and as a nutrient in the other. We attempt to understand how we can re-envision waste and water linkages in the PUIs of expanding cities if India needs to move towards a sustainable future