MODELLING THE EFFECTS OF A TIDAL LAGOON ON THE MORPHOLOGY OF SWANSEA BAY, WALES, UK

Abstract

The Severn Estuary (west coast of UK) is a highly dynamic environment and thus understanding of sediment transport under both natural and man-made changes is vital to the sustainable use of the coastal area in this region. The area is likely to be the site of the world's first tidal energy lagoon. The construction and operation of the lagoon will result in some localised changes to hydrodynamic processes, leading to some potential changes in sediment transport and depositional processes at identified receptors within Swansea Bay (Fairley et al., 2014, Fairley et al., 2016, TLSB, 2016). There are some concerns about the possible impacts on the Site of Special Scientific Interest - SSSI (Blackpill and Crymlyn Burrows) and Kenfig Special Area of Conservation - SAC (not shown on figure), located Southeast of the tidal lagoon. A three dimensional hydrodynamics model (DELFT3D) of the Swansea bay area has been set up to investigate the sediment transport dynamics within Swansea Bay and longer term hydrodynamics of bedform features in the area. This project will underpin improved environmental understanding and coastal management in the Swansea Bay region because the models produced will also provide input data for other projects reliant on tide, wave and sediment transport information in the area.