Coasts- Sandbanks Dorset CS Flashcards
Where is Sandbanks located?
-Sandbanks is a narrow, sandy peninsula located on the southern coast of England
-It is situated at the entrance of Poole Harbour, which is a large natural harbour on the English Channel
Why does sandbanks need managing?
-It has a large number of high value commercial properties built on it including sandbanks hotel and haven hotel which provide employment opportunities and generate spending in the local economy
-Beach is a major tourist attraction
-It provides protection and shelter from waves for poole harbour which is a popular and safe place for wind surfing sailing and water skiing
-home to numerous yacht clubs and marinas such as salterns
-Poole harbour is used by cross channel ferries and catamarans as well as commercial ships carrying goods such as timber (LSD could cause harbour entrance to become clogged and shallow)
-Residential properties are high in demand and command premium prices (large detached houses command prices in excess of £10m with many luxury apartments costing over £2m)
-Climate change means that sea levels are predicted to rise here by about 0.6m in the next 100 years which would cause flooding to properties but could breach the peninsula at its lowest and narrowest point
What management strategies have been used?
-In order to maintain a deep and wide beach rock groynes have been constructed to minimise the movement of sediment along the beach at sandbanks by LSD
-In addition beach recharge is used to conserve the beaches. Sand dredged from offshore is sprayed onto the beach, a process known as ‘rainbowing’ adding to its size
What are the impacts of using rock groynes and beach recharge?
-An impact of using rock groynes is it not only restricts sediment from entering the harbour entrance, thereby keeping access free from shipping but also absorbing wave energy and reducing rates of erosion. It is estimated that without this action, erosion rates would be about 1m per year
-An impact of using beach recharge would be the current cost is £20/m cubed. However in 2015 a trial of dumping sediment dredged from the harbour just offshore involves a much cheaper alternative, costing only £3/m cubed. Natural currents will eventually transport this sand onshore where it will help to build up beaches. However a review in 2018 suggested that only 3% of the 30,000 m cubed of sediment dumped off-shore had reached the beach after 18 months. In total over 3.5m m cubed of sediment have been added to poole bay beaches
