Overview
'Coastal environments are central to our culture and lifestyle.

South Australia has 4000 kilometres of coastline, ranging from cliffs, rocky shores and sandy beaches in the South East and West Coast to mud flats, seagrass, samphire and mangrove habitats in the upper St Vincent and Spencer Gulf regions. Our marine environment is an extremely valuable resource. Coastal and marine waters support large commercial and recreational fisheries, as well as aquaculture worth approximately $500 million a year to the State's economy.

South Australians are predominantly coastal dwellers and users. As a large proportion of our population lives near the coast, the health of coastal and marine environments is essential to our quality of life. Equally, a clean image is valuable to our seafood and tourism industries and maintaining biological diversity is also important in its own right. However, coastal and marine environments are placed under pressure by the concentration of population near the coast.

Adelaide's metropolitan coastal water quality ranges from good to poor (in certain locations). The discharge of wastewater and stormwater with high nutrient concentrations into the coastal environment has impacted significantly on the quality of our coastal waters. High nutrient levels in coastal waters compromise marine biodiversity by causing seagrass and mangrove dieback. Seagrasses and mangroves provide important nursery areas and habitat for many marine species. Large areas of these plant habitats have been lost in the past century, particularly in Gulf St. Vincent, but also Spencer Gulf and other select regional locations.

The natural movement of sand along the coast has been altered significantly in many locations along South Australia's coastline by building on the sand dunes, building hard structures along the foreshore and by the loss of seagrass. These historical changes have increased the natural erosion rates and the ability of the coast to absorb the erosion, leaving us with beaches that need to be maintained through manual beach replenishment programs or other methods.

The marine and freshwater fisheries of South Australia are renewable, but they are also limited and vulnerable. Our fisheries must be cautiously managed to ensure that commercial and recreational fisheries remain sustainable and that marine biodiversity is not adversely affected by overfishing or damaging habitats through fishing practices. Most of South Australia's fisheries are fully exploited (being fished at their maximum sustainable limit).

Aquaculture is the commercial growing of marine and freshwater animals and plants for the purposes of trade, business or research. The aquaculture industry in South Australia has developed very rapidly over the last decade and is diversifying and becoming increasingly economically significant. If inappropriately managed, aquaculture operations can have a significant impact on the environment. The aquaculture industry is now subject to much greater controls via licensing and environmental monitoring required under the Aquaculture Act 2001.