What Shapes Our Coastline?

There are four processes that shape our coastline:

  • Erosion
  • Deposition
  • Transportation
  • Accretion

Erosion is where land is broken down by waves and the sediment is carried away.

Deposition is where waves drop sediment onto the beach.

Transportation is where waves and tides transfer sediment somewhere else.

Accretion is where material builds up on a beach. This can be natural, caused by deposition or artificial through depositing sand via beach nourishment activities such as those undertaken at the Beresford Foreshore.

More information on the coastal waves, water levels and beach dynamics here

Changes in the Coastline

Changes to the coastline can happen over hours or days due to storm activity or over weeks and months due to seasonal changes in the ocean.  They can also take place over years such as El Nino and La Nina events or over decades on millennia due to sea level rise. 

Human activities can also impact the coast on all of these timelines.

Climate Change and the Coastline

How can climate change affect coastal processes? More information on climate change and the coast here

Sea level rise may increase erosion and inundation. More information on flooding here

Wave climate changes could increase or decrease wave run-up on the beach, increase or decrease erosion and accretion, or change sediment transportation.

Changes in storm frequency and intensity or a change in the direction of storms could change wave and storm surge patterns.

Changes to rainfall and runoff could increase or decrease sediment supply to rivers.

More information on climate change coastal dynamics here

What shapes our Coastline graphic