Depositional coastal Depositional coastal featuresfeatures

BeachBeach BarBar BarrierBarrier DuneDune Spit Spit TomboloTombolo

Tombolo- tied island

TomboloTombolo

Coastal formation of beach material Coastal formation of beach material developed by developed by refractionrefraction and and longshore driftlongshore drift to form a ‘neck’ to form a ‘neck’ connecting a coast to an offshore connecting a coast to an offshore island or breakwater island or breakwater

Shallow Inlet spit - aerial oblique photograph Shallow Inlet spit - aerial oblique photograph

Spit

groyne

Training wall

SpitSpit

Spits are long narrow ridges of sand which Spits are long narrow ridges of sand which project from the coastline into the sea.project from the coastline into the sea.

The formation of a spit begins due to a The formation of a spit begins due to a change in the direction of a coastline - the change in the direction of a coastline - the main source of material building up a spit main source of material building up a spit is from longshore drift which brings is from longshore drift which brings material from further down the coast.material from further down the coast.

DunesDunes

Beach dunes are formed by sand that is Beach dunes are formed by sand that is blown to the back edge of the beach. The blown to the back edge of the beach. The winds that blow off the ocean bounce sand winds that blow off the ocean bounce sand grains along the ground and also carry grains along the ground and also carry them through the air. them through the air.

Dune building is a gradual process and Dune building is a gradual process and plants play an important role in dune plants play an important role in dune formation. Roots stabilize the dune and formation. Roots stabilize the dune and above ground plant structures intercept above ground plant structures intercept and trap more sand. and trap more sand.

Coastal ManagementCoastal Management

Throughout the world there is a great Throughout the world there is a great concern about coastal environments. concern about coastal environments. There has been an increase in the damage There has been an increase in the damage caused by human actions that interfere caused by human actions that interfere with natural processes. with natural processes.

Foreshore development, especially where Foreshore development, especially where buildings are constructed on the dunes buildings are constructed on the dunes systems, are in danger of being washed systems, are in danger of being washed away. Even the construction of away. Even the construction of boardwalks, jetties and breakwaters have boardwalks, jetties and breakwaters have impacts on natural processes. impacts on natural processes.

Coastal management strategiesCoastal management strategies Construction of protective barriers and Construction of protective barriers and

walls to reduce erosion egg sea walls. walls to reduce erosion egg sea walls. These can detract from the appearance of These can detract from the appearance of the beach. Although they are designed to the beach. Although they are designed to reduce erosion they often increase the reduce erosion they often increase the removal of sand in front of the wall as removal of sand in front of the wall as energy scours the sand. energy scours the sand.

Breakwaters are constructed at the Breakwaters are constructed at the entrance of rivers to stop sand depositionentrance of rivers to stop sand deposition

Groynes are constructed at right angles to Groynes are constructed at right angles to the beach to catch sand moving with the beach to catch sand moving with longshore drift. longshore drift.

Replanting of dunes to stabilise sandReplanting of dunes to stabilise sand Removal of introduced species e.g. Removal of introduced species e.g.

bitou bushbitou bush Fencing off areasFencing off areas Beach nourishment- replacing sandBeach nourishment- replacing sand Buying houses on the coast and Buying houses on the coast and

removing the structures to enable removing the structures to enable the dunes to redevelopthe dunes to redevelop

Summary of coastal management Summary of coastal management techniquestechniques

Brief Brief description of description of management management strategystrategy

Advantages Advantages DisadvantageDisadvantage

Coastal managementCoastal management

YouTube - Coastal ManagementYouTube - Coastal Management

Different perspectivesDifferent perspectives

YouTube - A MESSAGE TO GOLD COAYouTube - A MESSAGE TO GOLD COAST CITY COUNCILST CITY COUNCIL