Managing our Metropolitan Beaches
There are locations along the Adelaide metropolitan coast which now have very unhealthy beaches, from Seacliff to Henley South and in particular West Beach, which has eroded to the point of virtually no sand.
Each significant storm event we experience wreaks more and more havoc on our beaches.
The loss of public access to the shoreline, and associated decline in revenue from coastally-dependent commercial activities, if not addressed appropriately, will result in significant environmental, social and economic costs.
SA-BEST proposes to establish an independent coastal management authority to manage our metropolitan beaches, including a specialist team with marine ecology, oceanography, coastal geology, coastal engineering and surveying expertise.
The authority will investigate the historical data of the coast, along with future hazard assessment, separated into sections or ‘cells’, to identify high risk areas requiring urgent action.
Each cell must be addressed individually as there will not be a ‘one size fits all’ solution. Strategies to counter the effects of structures, for example the Adelaide Shores boat ramp, on our loss of beaches, will need to be specifically considered.
Overall, each local analysis will then contribute to a collective plan and a progressive restoration of our metropolitan coast.
We must undertake an initial assessment within the first six months and commence implementation of solutions within the first year, to stop further erosion and increase public safety.
SA-BEST also supports stronger community participation in regular monitoring and updates on the health of our coastlines and reporting any damage and hazards resulting from weather events.
The Adelaide Coastal Waters Study of 2007 recommended, as a matter of priority, that steps must be taken to reduce the volumes of wastewater, stormwater, and industrial inputs into Adelaide’s coastal environment. This should be done within the context of an overarching strategy designed to remediate and protect the metropolitan coastal ecosystem.
Effluent and stormwater being discharged along the coast is changing the biology of the water in the gulf, which in turn is having a detrimental effect on the seagrass. Once seagrass becomes lost offshore, the seabed becomes scoured, water depth increases, and higher energy wave action occurs closer to shore which then causes significant damage to our beaches.
SA-BEST supports investigating emerging technologies and alternative treatments to decrease the harm caused by effluent and stormwater to seagrass; and trialling of seagrass seeding to increase the density and coverage of seagrass along our coastline. This, in turn, should improve sand retention and water quality, and promote aquatic biodiversity.
SA-BEST also proposes a review and upgrade of the metropolitan sand pumping system as a priority, as the current system is just not working. Sand pumping and trucking needs to continue until systems are in place, then this should need to occur less and less frequently.