Author(s): Reza Ahmadian; Roger Falconer; Bettina Bockelmann-Evans
Keywords: Severn Barrage; Hydro-environmental Modelling; Marine Renewable Energy; Severn Estuary; Barrage Operation
Abstract: The Severn Estuary located between South Wales and South West England has a tidal range of around 14 m which makes it the third highest tidal range in the world. With marine renewable energy becoming more significant in many parts of the world, due to its predictable nature and the increasing cost of natural resources, there have been a number of proposals for various marine renewable energy schemes to be built in the estuary, including several tidal barrages. The CardiffWeston (or Severn) barrage is considered to be one of the most favourable of these proposals. This barrage, which will be the world's biggest tidal renewable energy scheme if built, will have a significant environmental and ecological impact on the estuary, whilst generating about 5% of the UK's electricity. This study mainly focuses on investigating the hydro-environmental and ecological impacts of the proposed barrage by modelling the structure using linked 1-D/2-D hydro-environmental models with the capability of modelling several key environmental and ecological processes. To investigate the importance of the different operational schemes on the environmental and ecological impacts, a twoway generation scheme was also used in this study as well as the commonly investigated ebb-only generation scheme.