Shoreline Evolution, Erosion and Flooding
The coastline is a complex and dynamic environment, continually changing and evolving due to the prevailing conditions, extreme events, natural processes and anthropogenic influences that operate there. Variations in the rate, scale or frequency of these coastal processes can have serious implications on the communities, land use and natural environments affected, often resulting in erosion of beaches and cliffs, or extensive tidal flooding.
Within the Solent, beaches have generally declined in front of defences over the past 100 years, a process that has been attributed to defences that have slowed or halted barrier transgression preventing reworking of gravel deposits of the coastal plain and reduced landward inputs from ebb tidal deltas potentially related to major dredging activities. Shoreline stability has been achieved only by continued management of coastal defences.
The scale and rate of historic and projected loss of saltmarshes and inter-tidal mudflats throughout the Solent has been identified and quantified through the Solent Dynamic Coastal Project, and Solent Coastal Habitat Management Plan (CHaMP) research projects. Rates of narrowing are likely to increase due to sea-level rise and increased wave energy associated with climate change; trends of saltmarsh and mudflat erosion are likely to continue into the future and total losses should be anticipated in the medium to long term on the exposed frontages. As these inter-tidal areas are lost, the upper shores will become exposed to increasing wave energy and erosion and low lying land will become increasingly vulnerable to flooding.
Monitoring of the shoreline and nearshore zone aids managers, planners and politicians in identifying and understanding the importance of existing and future requirements for coastal erosion and flood risk measures, and to determine, control or prevent development at or near the coast.
