Coastal Erosion in Selsey
The long battle against the sea
Coastal erosion has been a defining challenge for Selsey throughout its history. The town sits on a low-lying peninsula composed of soft clay, gravel and sand, and the exposed position at the tip of the Manhood Peninsula means that the coastline is subject to the full force of storms from the south-west and the relentless action of tides and waves.
Historical records and maps show that Selsey has lost significant areas of land to the sea over the centuries. The original site of the Saxon cathedral is believed to lie beneath the waves south of the present coastline. Streets, houses and farmland have been claimed by erosion, and the shape of the peninsula has changed markedly since medieval times. The submerged forest visible at extreme low tides off Selsey Bill is a reminder that the land once extended much further into the Channel.
The sea defences at Selsey have been built, repaired and strengthened many times. Rock armour, concrete walls, groynes and shingle recharge have all been used to protect the coastline and the properties behind it. The defences are maintained by the Environment Agency and Chichester District Council, and the cost of upkeep is substantial. The great storm of October 1987 tested the defences severely, and subsequent storms have caused damage that requires ongoing repair.
The Medmerry managed realignment scheme, completed in 2013, represented a different approach to the erosion problem. Rather than continuing to defend the old shingle sea wall on the western side of Selsey, the Environment Agency chose to retreat the defence line inland, allowing the sea to flood the farmland in front while building a new embankment to protect the properties behind. The scheme reduced the flood risk to over 300 homes and created new wildlife habitat, demonstrating that managed retreat can be a viable alternative to hard defence.
Climate change and rising sea levels are expected to increase the pressure on Selsey's coastline in the coming decades. The Shoreline Management Plan for this stretch of coast identifies different policies for different sections, ranging from hold the line where properties are at risk to managed realignment where the coast can be allowed to retreat. The balance between protecting homes and accepting natural coastal change is a sensitive issue in a community where many people live close to the sea.
For Selsey residents, coastal erosion is not an abstract environmental issue. It is a daily reality that affects property values, insurance premiums, planning decisions and the physical landscape of the town. The sight of waves breaking against the sea defences during a winter storm is a powerful reminder of the forces that have shaped this coast for millennia.