Coastal Management Northern Beaches Sydney Collaroy to Dee Why Case Study The Geographical Processes and Human Impact (involving development, beach replenishment, etc.)

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The coastline is a major part of an Australian's life. There is over 30,000km of coastline, and with 85% of people living within 50km of the coast, the management strategies of the coast is extremely important. This report will investigate Dee Why and Collaroy Beach's coastal management and the subsequent consequences.

Dee Why and Collaroy beach are part of the northern beaches, located on the Collaroy Plateau, approximately 20km from the Sydney CBD. Dee Why beach is 1.2km long, while Collaroy Beach is 3.4km long, both located at approximately 33S 151E.

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The accretion-erosion cycle is caused by destructive and constructive waves. Beaches undergo submersion as a result of destructive waves, and accretion as a result of constructive waves. Submersion is where sand is moved from the visible part of beach to a submerged nearshore region. Accretion is when the sand moved during submersion is moved back to the visible section of beach. This is known as the accretion-erosion cycle.