Dredging Outer Harbor

consisted of national and international water experts, state and local government representatives, community and environmental organisations, and a number of universities.

WACRA played a significant role representing the community. Our collective role was to provide a report to the government minister on recommended actions, responsibilities and findings by March 2007 (Torrens Taskforce Final Report, May 2007).

The determination of WACRA to seek out funding and commitment from the federal, state and local governments to complete the third stage of the wetland has been a standing item on our agenda. In 2015, many meetings, submissions and presentations resulted in the Natural Resources Management (NRM) Board working with key stakeholders to develop a concept plan for this section of the waterway. Although things went quiet due to changes in government, we were nevertheless relentless in pursuing funding commitments from the three levels of government.

Things started to move when the City of West Torrens closed off the horse facilities at Lockleys Oval and agreed on a plan to shift them to a new modern facility in Apex Park on the southern side of the Torrens riverbank. An additional funding commitment of $12 million was promised by the federal and state governments, City of Charles Sturt and City of West Torrens to complete the final stage of the wetland.

In November 2020, the concept plan is being finalised. It is promised that work will commence in spring 2021. Breakout Creek wetlands will be an environmental and ecological showpiece which will have met its vision and objectives.

Stage 1 Breakout Creek (east of Tapleys Hill Road)

Dredging Outer Harbor

Peter Schultz

In May 2018, the state government granted the Flinders Ports corporation development approval to widen the Outer Harbor shipping channel. Larger ships are being used by international shipping companies and Post-Panamax vessels have a width of 49 metres. Currently vessels 35 to 42.2 metres have restricted accessibility to the port at Outer Harbor.

Widening involved increasing the width of the 7 kilometres channel from 130 to 170 metres, and dredged materials were to be dumped 29 kilometres offshore in Gulf St Vincent. WACRA opposed the application before the State Commission Assessment Panel (SCAP), arguing strongly for land-based disposal of the dredged material, and that stance has never changed. There was a community and stakeholder engagement period for permit and licence applications and WACRA was one of the most active organisations involved in the discussions. Among the WACRA suggestions adopted in the final licence agreement were real-time monitoring of turbidity and GPS tracking of all vessels disposing of dredging spoil. We also sought real-time access to this data. Land-based disposal was rejected, as was a monitoring location within the Port River.

WACRA acknowledged that the channel needs to be widened but is concerned about seagrass loss in Gulf St Vincent as well as biosecurity. South Australian oyster growers are currently free of Pacific Oyster Mortality Syndrome (POMS), but POMS occur within the Port River area in local bivalves, as does the feral algae species Caulerpa taxifolia that has not yet reached Gulf St Vincent.

In 2019, WACRA and many other interested bodies attempted to promote dredging methods that cause the least harm by ensuring that licence conditions are stringent, limits are set on turbidity, seagrass health is monitored, and that Flinders Ports have monitoring, recording and reporting systems in place. The final licence included two complex running median levels of turbidity with triggers to reduce turbidity implemented when they exceeded levels set by the Environment Protection Authority (EPA).

WACRA (and other community groups) undertook to watch and see how the monitoring systems were working. We understand that the EPA stopped dredging whenever the turbidity increased beyond trigger levels. The scientists in this organisation monitor seagrass health independently using satellite technology. In terms of monitoring data, public access in real time has only been partly delivered, with running medians upgraded hourly but no access to actual recent data. We await an update on monitoring for the deadly POMS, a role being undertaken by the Fisheries and Aquaculture Division of Primary Industries and Regions SA (PIRSA). Flinders Ports was responsible for monitoring the seagrasses for at least three years after the dredging, not only for the three months during the dredging process.

The placement area of dredged materials is the same as the 2005 channel deepening project, and at that time significant seagrass was lost. The dredge plants arrived at Outer Harbor in June 2019, and channel widening will be completed for the 2019-20 cruise season, which commences in October 2019. A total of 79 cruise ships are expected to visit South Australia 2019-20. The new channel will allow the largest container vessels afloat unrestricted access to Outer Harbor in the future.