Designing sustainable estuarine intertidal habitats Available to Purchase

The creation of intertidal habitats, especially in estuary areas, has become increasingly popular in the UK over the last ten years. The complexities of artificially creating sustainable natural habitats means that the design of schemes requires an appreciation of a number of interrelated parameters. Morphological considerations are particularly important and include the site elevation, gradient and presence or absence of creek networks. Other important design considerations relate to hydraulic factors such as the exposure to wave action and tidal currents, the tidal prism and the inundation period. Relevant hydrological factors encompass aspects of water quality such as salinity and pollutant levels. Sedimentological considerations comprise sediment supply, particle size, consolidation rates, organic content, sediment chemistry and sediment quality. Since natural habitats are dynamic features, this paper also describes the tools available for investigating the short-and long-term evolution and stability of proposed schemes. Over the long term these tools include the analysis of historical charts, photographs and maps; the use of regime theory and various empirical relationships. Over the shorter term numerical modelling of tides, waves and sediment transport can be used. The scale of assessment and the approaches which are adopted are likely to be influenced by the size of the scheme and the number of associated issues. However, the complexity of processes within estuary systems means that it is often beneficial to use a range of techniques and synthesise the results to reduce uncertainties.