Aqua (Jun 2022)
Assessment of dam-induced changes in ecogeomorphological behaviour and fluvial functionality in the Damodar River, West Bengal, India
Abstract
Anthropogenic interventions in the form of dams and barrages often alter the fluvial functionality and eco-geomorphological (geomorphology, hydrology, and ecology) behaviour of river systems. The present work examines the environmental flow, channel metamorphosis, and fluvial functionality of the Damodar River in the context of Damodar Valley Corporation (DVC) dams and development. Structural (dams, barrages, weirs, etc.) and non-structural (urban–industrial and agricultural disposal with effluents, sand mining, etc.) interventions hinder the ecological functionality of the river. This study portrays that the eco-geomorphological behaviour and fluvial functionality of the river have changed due to flow alteration and diversion by dams and barrages and due to rapid urban–industrial and agricultural growth in the basin area. These changes have affected riverine ecological integrity. The ecological functionality level of this study area ranges from 85 to 181, i.e. from poor to good–fair. The ecological functionality level in the sample channel sections (i.e., the immediate upstream and downstream of the Durgapur Barrage) is poor, and the value ranges from 61 to 100 due to the hydrological impact of the barrage and the Durgapur urban–industrial belt. This assessment work will help to restore the fluvial environment for humans as well as riverine biota. HIGHLIGHTS Dams and barrages have altered the hydrological flow regimes, affecting the eco-geomorphological behaviour of alluvial channels.; Dam-induced fluvial metamorphosis is evident in the channel morphological parameters and channel classification.; The fluvial functionality index has been applied to evaluate the ecological functionality level for the restoration of the riverine environment.;
Keywords
