1. The Coast 1

2. The Sea 2 Wind Waves

3. The Sea 3 TidesCurrents 1.Long-Shore 2.Cross-Shore

4. The Sea 4 Currents

5. Shore protection structures 5 Groins A groin is a shore protection structure designed to build a protective beach or to retard erosion of an existing beach by trapping littoral drift Groins are usually perpendicular to the shore and extend from a point landward into the water far enough to accomplish their purpose

6. Shore protection structures 6 The effect of groins on the coast Groins interrupt the longshore transport. As a result accretion occurs at the updrift side and erosion at the downdrift side The re-orientation of the shoreline between the groins results in local retreat of the shoreline relative to the original position. This can be restored by applying some sand nourishment between the groins.

7. Shore protection structures 7 Groins A system of groins may be an effective coastal protection scheme, and it can be considered as a proven technology for which the effects on the coast can be reasonably well predicted.

8. Shore protection structures 8 Jetties Jetties are structures used at inlets to stabilize the position of the navigation channel, to shield vessels from wave forces, and to control the movement of sand along the adjacent beaches so as to minimize the movement of sand into the channel.

9. Shore protection structures 9 Jetties The sand transport into an inlet will interfere with navigation and will usually necessitate more frequent dredging to maintain the navigation depth. Because of the longshore transport reversals common at many sites, jetties are often required on both sides of the inlet to achieve complete channel protection

10. Shore protection structures 10 Breakwaters 1.Shore Connected 2.Offshore Shore Connected Breakwaters Shore connected breakwaters are used to shelter commercial harbors and small craft marinas by creating calm water in a harbor area, and provide protection for safe mooring, operating and handling of ships, and for harbor facilities

11. Shore protection structures 11 Breakwaters 1.Shore Connected 2.Offshore Offshore Breakwaters An offshore breakwater is a structure that is designed to provide protection from wave action to an area or shoreline located on the leeward side of the structure. This system is usually built approximately parallel to the shore or to the predominant wave train.

12. Shore protection structures 12 Offshore Breakwaters Detached Breakwaters have many advantages over other conventional forms of shore protection. Unlike groins, they allow sand to be transported alongshore, protecting the local beach, but not depriving downdrift beaches of sand.

13. Shore protection structures 13 Nourishment (Beach fill) Beach fill is a traditional and increasingly popular method of shore protection and flood control, and nourished beaches also have value for recreational, commercial, and environmental purposes.

14. Shore protection structures 14 Nourishment (Beach fill) Nourishment is a process of feeding a beach periodically with the amount of sand that was lost during this period. Fill is commonly placed together with the building of coastal structures such as groin fields and detached breakwaters

15. Shore protection structures 15 Nourishment (Beach fill) When the natural protection system fails during large storms, the first solutions frequently chosen are quasi-natural methods such as beach nourishment or artificial sand-dune building. Such solutions retain the beach as a very effective wave energy dissipater and the dune as a flexible last line of defense.

16. Shore protection structures 16 Seawalls and Revetments Seawalls and revetments are structures placed parallel or nearly parallel to the shoreline to separate a land area from a water area. They do not attract the sand or prevent longshore transport, but they only hinder the transport and protect the backshore.

17. Shore protection structures 17 Seawalls and Revetments Seawalls are simply retaining the beach material behind them, so they can be assumed as a retaining wall that should be maintained stable. They can be built so high that no water would overtop the crest of the structure and wing walls must be designed to prevent progressive failure that may be found at the ends of the structure

18. Shore protection structures 18 Seawalls and Revetments If they are permeable, they absorb part of the energy of the incoming waves and reflect the other part back to the sea.