Beach replenishment

Under natural conditions, some Adelaide beaches are constantly building up, some beaches are 'stable' and other beaches are eroding. Beach replenishment takes sand from beaches that are building up and places it at beaches that would otherwise erode away. There is only a finite amount of sand on Adelaide's beaches, so it must be spread in an equitable manner along the coast.

The sand put on a beach during replenishment is 'sacrificial'. It is intended that some of it be washed away during the next storm. If this replenishment sand weren't available to be eroded away, then beaches, dunes and foreshore reserves would be eroded instead. Much of the sand that is washed offshore during storms is washed back onshore during calmer periods, so it is not wasted.

Beach replenishment does limit the natural processes taking place on the Adelaide coastline to some extent. However, if beach replenishment weren't carried out, the natural processes would result in our southern beaches quickly losing their sand and the shoreline eroding inland. Storms would progressively erode dunes on the southern beaches, resulting in extensive damage to reserves, roads and buildings built on the foreshore.

There are numerous examples worldwide of successful beach replenishment programs. The success of Adelaide's beach replenishment program is demonstrated by the build-up of dunes and the increase in beach width at Brighton and Henley beaches. Previously in these areas, there were only seawalls and no beach at high tide.

Data from the monitoring program shows that the width of the beach at Brighton has built up by approximately 50 metres since 1975, despite an estimated 70,000 cubic metres of sand moving out of the area each year. Similarly, the width of the beach at Henley has built up by about 20 metres since 1975, despite an estimated 50,000 cubic metres of sand moving out of the area each year.

More information 

Refer to our reference material page.