The coastal waters west of Adelaide are part of Gulf St Vincent.
Gulf St Vincent contains the water north to Port Wakefield, west
to the shores of Yorke Peninsula and south to Cape Jervis.
A large part of the Gulf St Vincent shoreline is sheltered, with
shallow slopes creating safe swimming beaches. Adelaide's metropolitan
foreshore is typically made up of sandy beaches, with seagrass
meadows spreading more than 5 km out to sea. Central to these
beaches in summer are the jetties, which provide shade on the
beach and a base for anglers.
Ecologically, the waters of Gulf St Vincent are quite varied,
with seagrass, sand and reef
environments supporting important feeding grounds and nurseries
for fish, crustaceans, molluscs and marine mammals. Good water
quality is essential for the maintenance of these marine habitats,
and endangering them may risk biodiversity, wild and commercial
fisheries, and aquaculture.
Pollution in coastal waters may put recreational users at risk,
particularly swimmers. This could result in beach closures for
public safety. Pollution may also reduce the attractiveness of
the water and can cause algal blooms and fish kills.
Wastewater treatment plants and stormwater outlets discharge
into Gulf St Vincent. These discharges are high in nutrients and
suspended solids and can contain heavy metals such as copper and
zinc. The biggest problem is the large quantity of nutrients,
which are causing algal blooms, seagrass loss and other effects.
The loss of more than 50km²of seagrass along the Adelaide
metropolitan coast has been attributed to this pollution.
