Case study: coastal management in Holderness

The Holderness coast is in the north east of England. This is one of the most vulnerable coastlines in the world and it retreats at a rate of one to two metres every year.

The problem is caused by:

• Strong prevailing winds creating longshore drift that moves material south along the coastline.
• The cliffs are made of a soft boulder clay. It will therefore erode quickly, especially when saturated.

The village of Mappleton, perched on a cliff top on the Holderness coast, has approximately 50 properties. Due to the erosion of the cliffs, the village is under threat.

In 1991, the decision was taken to protect Mappleton. A coastal management scheme costing £2 million was introduced involving two types of hard engineering - placing rock armour along the base of the cliff and building two rock groynes.

• Mappleton and the cliffs are no longer at great risk from erosion.
• The rock groynes have stopped beach material being moved south from Mappleton along the coast. However, this has increased erosion south of Mappleton. Benefits in one area might have a negative effect on another.

The increased threat of sea level rise due to climate change, means that other places will need to consider the sustainability of coastal defence strategies for the future.