Author(s): William G. Bennett; Thomas J. Van Veelen; Tom P. Fairchild; John N. Griffin; Harshinie Karunarathna
Keywords: Delft3D; Vegetation; Coastal Flooding; Coastal Management
Abstract: Coastal management strategies in the UK are coming under increasing scrutiny, due to the declaration of a climate emergency, and the governments commitments towards it. Thus, there is additional pressure to consider more sustainable coastal management options, which involve the natural environment. In this study, a coupled Delft3D FLOW-WAVE-Vegetation model of the macrotidal Taf estuary in South West Wales, UK is used to investigate the role of salt marsh management on coastal flooding. The function mitigation function of saltmarshes within this estuary was modelled under two contrasting storm conditions, and with three management interventions implemented for comparison with the current condition ‘no-intervention’ scenario. Certain saltmarsh management interventions are shown to have widespread impacts on estuarine hydrodynamics. The effect of extensive salt marsh grazing by livestock caused an increase in wave height over the marsh areas, while tidal currents within the estuary were also found to have increased as a result of managed realignment of the marsh area. Thus, it is important to understand the impact of the management interventions considering the context in which they are implemented.