Coastal areas face problems of erosion and flooding due to rising sea levels and increased storm activity. This threatens homes, businesses and tourism. Coastal defenses use hard engineering like seawalls and groynes, or soft engineering like beach nourishment and managed retreat, to protect coastlines. However, all methods have disadvantages such as visual impacts or increasing erosion elsewhere. Coastal resorts also struggle with declining visitor numbers from overseas competition and require solutions like improving attractions to revitalize their economies.

1. Problems and Solutions in Coastal Areas Coastal Erosion & Decline in Coastal Areas

4. There are 2 types of Coastal defence techniques. 1. HARD ENGINEERING - this is where man made coastal defence structures are used to reflect large amounts of wave energy and hence protect the coastline. 2. SOFT ENGINEERING - this is where beaches or naturally formed materials are used to control / re-direct erosion processes. You need to know examples of coastal management techniques and their advantages and disadvantages:

5. What do you know about coastal defences?

7. Sea Wall A concrete wall which is curved on the underside to deflect the power of the waves These can be very expensive (up to £1-2 million per km) and the deflected waves can scour material at the base of the wall causing them to become undermined These are however a very effective means of preventing erosion and they reflect rather than absorb wave energy.

8. Rock Armour/Rip-Rap 2. Rip Rap Large boulders on the beach absorb wave energy and break the power of the waves Although movement of the boulders is expensive this can be a much cheaper method than some other solutions The boulders can however be undermined easily by waves washing away sand and shingle beneath them. They also can be quite ugly, changing the appearance of a coastline.

10. How do groynes work? Groynes trap the sand which is carried along the coast by longshore drift . The sand acts as a natural protection against the force of the waves. The waves break onto the beach and not the cliffs.

11. Gabions These cages of boulders are built into cliff faces to protect the cliff from the force of the waves; they are cheaper than sea walls and can be very effective where severe erosion is a problem They are however visually intrusive

12. Revetments These wooden structures break the force of waves and beach material builds up behind them They are cheap and effective at breaking waves As well as being visually intrusive however they do need replacing more frequently than most other defence methods.

14. Beach Nourishment Beach material is added to provide a "natural solution". Environmentally this is a preferred option as it maintains the beauty of the landscape and avoids visual intrusion, however it can be expensive to maintain as longshore drift continues to move beach material down the coast and therefore regular replenishment is required. Sand Dunes and salt marshes can also be encouraged to act as natural barriers to the waves.

15. Managed Retreat Managed retreat is also known as managed realignment. It involves breaching an existing coastal defence, such as a sea wall, and allowing the land behind to be flooded. This land is then left to be colonised by saltmarsh vegetation. When established, the vegetation disperses wave energy, reduces erosion rates and provides new habitats. The first attempt at managed retreat in the UK was on Northey Island, located in the Blackwater Estuary in Essex.

16. Study the photo and map extract. Is this Peveril or Ballard Point? pier Swanage Bay

17. What has been done to protect Swanage?

18. What is the best method of coastal protection? There are strong feelings about what should be done to protect Seaview!