FORESHORE MANAGEMENT PLANNING: A SEVERN ESTUARY CASE STUDY

Along the northern coastline of the Severn Estuary there is an extensive area of reclaimed land known as the Gwent Levels. This land is protected from flooding by 50km of sea defence embankment. The effectiveness of this structure is dependent on the degree of tidal and wave energy dissipation along the adjacent foreshore. The inter and sub-tidal areas of the Severn Estuary have witnessed major morphological change within the recorded past. Such changes have traditionally resulted in sympathetic sea defence reinforcements or realignments. The Gwent Levels Foreshore Management Plan (FMP) was tasked with the development of a strategy to sustain the existing and future sea defences and to optimize the use of resources via planned rather than reactive measures. This paper presents the innovative approach taken in the plan development and discusses details from the study inception through to the conceptual design of capital improvements. Technical advancement has been made in developing the understanding of the morphological evolution of such systems. This has been achieved by applying recently developed methods of data recovery, integrating mapping techniques and re-interpretation of historical data sets. The morphological response of the foreshore is highlighted in relation to the changing practices along the foreshore and the sea defences. Although described at an estuary specific level these methods may be utilized in other estuarine and open coast systems.