The coastline of Norfolk and Suffolk has been the site of many coastal defence schemes for a number of years. Various local councils have put up all types of defence in order to stop cliff tops being eroded away and also beaches from disappearing and this is a battle that is still being fought today. The area is under threat due to two major issues. Firstly the land is highly susceptible to coastal erosion. The cliffs comprise of permeable rocks such as sandstone and chalk lying on top of impermeable rocks such as Clay. Water gets stored between the rock types and produces slip zones. Most coastal erosion has occurred after periods of heavy rainfall. This produces a situation where waves attacking the bottom of the cliff are helped by sub aerial processes such as rainfall destabilizing the insides of the cliff.
The whole area is in one large sediment cell. This means that whatever material is eroded from a cliff is later deposited somewhere else along a coastline. The coastline is kept in a balance and this results that the large beach at Great Yarmouth is reliant on a cliff further down the coastline being eroded. If one council defends a cliff what is likely to happen is that some beaches close by will start to disappear as they no longer receives any new sand. The best way to protect a cliff from erosion is to have a large beach. Firstly it physical stops the waves eroded the base, and secondly it dissipate’s the waves energy. This means that by the time the wave gets up the beach the energy to erode has disappeared.
The whole region now has a management plan as experience has shown that councils working alone do not fix the problem, they just pass it on to a council further down the coastline. Managed retreat is a favored option of defending the line. This method involves protecting the most valuable land with defences while at the same time allowing low grade land to be eroded by the sea.
The coastal towns in the region have used a wide variety of defence schemes to protect their land. The most popular form of defence used when councils want rural areas to be protected, is by using groynes. The aim of the groyne is to capture and hold sand that is being transported along the coast by long shore drift. This new beach then defends the bases of the cliffs and erosion stops. An easy way to see to if a cliff is being eroded is to check its color. If it is green then it isn’t as vegetation has been able to grow and if no vegetation is present then it is likely that the cliffs are being eroded.
The towns in the area have used other methods to protect their most valuable land. The use of a seawall is the most expensive sea defence but is also the most effective. The sea wall at Sheringham was built in 1895 and acts as a promenade for tourists as well. At the bottom of the wall is rock armory which stops the base of the cliff being attacked by the waves. In 2013 the wall was breached by waves and large areas of the town was flooded. The main problem is now rising sea levels that have occurred as a result of global warning. In 2014 plans were unveiled to stop the flood from occurring again and this has come at a cost of 804,000 pounds. This will see the promenade being widened, steel reinforcements being installed at the base of the wall and general repairs upgrading the condition of the wall.
The authorities hope that these new repairs will stop the town being flooded for another 50 years. Whether this holds true if sea levels continues to rise is another matter. What is important is that the area to the west of the town is left to erode naturally so that it can replenish Sheringham’s beaches.