15. Environmental Impact Assessment: A Case Study on East Kolkata Wetlands

Wetlands are renewable and cost-effective complex nature of integrated natural biological resources. The wise use of aquaculture in the form of sewage-fed fishery provides a multitude of ecological functions such as flood reduction, groundwater recharge, habitat and biodiversity restoration, employable opportunity, etc. Wetlands are classified into 19 categories to include all varied nature of wetlands starting from plain land to high altitude as well as man-made to natural. Sharp decline or destruction of these ecosystems due to serious human intervention poses a threat to environmental sustainability. The present study highlights the steps of impact assessment, its different processes, evidences of impact assessment, impact analysis using diverse parameters to establish a report on management and monitoring of wetlands with special reference to East Kolkata Wetlands (EKW). The US Environmental Protection Agency (USEPA) has adopted three tiers or levels of methods for assessment system. East Kolkata Wetlands are unique ecological sensitive areas and are established as wise use of wetlands where the city sewage is used by mastering the activities of resource recovery. It also focused on the process of initial environmental examination (IEE) and strategic environmental assessment (SEA) which are recognized as the outcome of Agenda 21. Finally, impact analysis of biological organisms, especially fish through histological, histochemical, topological, enzymological and hormonal studies would be the important and added methods and techniques for future workers in the process of conceptual modelling on wetlands.