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The Port Adelaide Seawater Stormwater Flooding Study concluded that floodwaters were able to be
contained within the wetlands and basins, even in high ocean conditions, due to their large storage
volumes. However this was based on the assumptions that the wetlands and basins were at their
operating levels or empty prior to the flood event. In terms of sea defence, the study showed that portions
of the Outer Harbour area are at risk of seawater inundation and have suggested various mitigation
infrastructure including seawalls and stormwater pump stations and stormwater detention basins.
Similarly the current water level of West Lakes may be below sea level if sea level rises are realised.
West Lakes currently relies on tidal systems to circulate water and an engineered solution may be
required if this no longer becomes possible (E Pikusa, pers com, 19/07/12).
12.2. Dry Creek
The Dry Creek catchment lies predominantly in the City of Salisbury Council area. Dry Creek is an
ephemeral stream which runs through PAE prior to discharge into the Barker Inlet. A weir has been
installed on the creek to create wetlands designed to capture 1000ML of water each year to be stored in
local aquifers.
A gauging station was installed on Dry Creek at Bridge Road, just downstream of the boundary of PAE, in
1994 and remains open.
Flood maps for the Dry Creek catchment are not currently available.
12.2.1. Climate Change Implications for Catchment Management
Dry Creek is an ephemeral watercourse which begins in the Adelaide Hills. The Dry Creek wetlands have
been designed to dry out in summer. The impact of climate change on these wetlands, with reduced
average rainfall and more frequent intense storms, is less likely to be severe due to their current
operations.
12.3. Torrens River
The Torrens River catchment spans over 637 km
2
from the Adelaide Hills to the Gulf St Vincent. Its
catchment varies from rural to urban developments. The main sub-catchments within the Study Area
include Henley-Fulham, Torrens East and Torrens West sub-catchments. Upstream of the Study Area,
notable major reservoirs within this catchment include Kangaroo Creek, Millbrook and Hope Valley.
The River Torrens is the major waterway in this catchment. It is a naturally occurring water course which
has been widened and lined with concrete and stone in sections. The Torrens Weir was built in 1881 to
create a recreational lake in the City of Adelaide. In 1934, Breakout Creek was constructed to give the
River Torrens a direct outlet to the sea. There is a gauging station on the Torrens River at Holbrooks
Road which was installed in 1978 and remains open.
There have been two wetlands constructed in the Torrens River catchment. These are the Breakout
Creek wetlands and the Apex Park wetland. Breakout Creek is located at the coastal end of the Torrens
River and receives stormwater from the surrounding suburbs in addition to stormwater from the upper
reaches of the River Torrens. Works on extending these wetlands are still in progress. The Apex Park
