Topic: Rivers & Coasts Case Study:Coastal Management Case Study Location: The Holderness Coast, East Yorkshire Geographical Keywords • Hard engineering • Rock Armour (Rip-Rap) • Sea Wall • Revetments • Gabions • Groynes • Soft Engineering • Longshore Drift • Boulder Clay • Shoreline Management Plan • Erosion • Slumping • Economic value Case Study Detail Background The Holderness Coast is located on the east coast of England. It extends km from Flamborough in the north to Spurn Point in the south. It is one of Europe's fastest eroding coastlines. The average annual rate of erosion is around 2 metres per year. This is around 2 million tonnes of material every year. Underlying the Holderness Coast is bedrock made up of Cretaceous Chalk. However, inmost place this is covered by glacial till deposited over 18,000 years ago. It is this soft boulder clay that is being rapidly eroded. The shoreline management plan of this coast varies as you move along it. Areas that have economic value have hard engineering in place to prevent coastal erosion, while areas of coastal farmland have little protection. Hornsea Management The seaside town of Hornsea has hard engineering to protect the town from coastal erosion. Anew concrete lipped seawall protects most of the town with an older stepped seawall further south. Along the beach are numerous timber groynes which trap sand, protecting the coastline and providing an attractive beach for tourists. More recently rock armour and a steel reventment has been erected to the south of Hornsea. This helps protect the caravan park. South of the caravan park where the protection ends, the coastline is noticeably more eroded with lots of evidence of slumping of the boulder clay. Mappleton Situated approximately km south of Hornsea lies the village of Mappleton. Supporting approximately 50 properties, the village has been subject to intense erosion at a rate of m per year, resulting in the access road being only m from the cliff edge at its closest point. In 1991 almost £2 million was spent on two rock groynes and rock armour along the coastline to protect Mappleton and the B coastal road. Blocks of granite were imported from Norway for the sea defences. The purpose of the two rock groynes was to trap beach material. As the result of the coastal management a substantial beach accumulated between the groynes halting erosion. However, like Hornsea, the coastline south of Mappleton has no protection, and because it is starved of sediment (trapped at Mappleton) it experiences far worse erosion. Many residents blame the rock groynes at Mappleton for the loss of their land.
