Coorong Infrastructure Investigations Project

Project objective

The objective of the Coorong Infrastructure Investigations Project (CIIP) is to investigate the feasibility of multiple long-term operational infrastructure options to improve the ecological health of the Coorong.

The problem

The hydrology of the Coorong, Lower Lakes and Murray Mouth system has been dramatically altered over time.

Maintaining the long-term ecological health and resilience of the Coorong may not be achievable through improved knowledge and water resource optimisation alone.

Operators have very few tools to manage flows efficiently and effectively within the Coorong and in particular the Coorong South Lagoon.

Additional management options may be required, particularly in the face of climate change.

What we are doing

CIIP is investigating the feasibility of long-term infrastructure and management for improving the health of the Coorong.

The below timeline shows the various project milestones throughout the investigations process, including:

  1. Identifying and shortlisting options (May to September 2020)
  2. Investigating the feasibility of the options (November 2020 to December 2021)
  3. Putting together a business case for the consulted option (January 2021 to June 2022)
  4. Implementing the decided option (2022 to 2024)

DEW is committed to involving the community in every step of the process and will be consulting with the community throughout the project.

 ciip-timeline.jpg

What have we done so far?

During the first stage in the engagement process for CIIP, options identification and shortlisting, a survey was circulated to the community to measure what they thought was important in evaluating options for the Coorong. They were also given an opportunity to offer any new ideas that they thought should be considered.

From this survey, a group of interested community members came together on behalf of the broader South Australian community, to decide on a list of things that they felt were important in determining the best option.

The community members determined that the most important, essential outcome, is finding:

“the option/s that best contributes to improving the ecology of the South Lagoon as determined by scientific evidence, given water availability and constraints.”

In June 2020, we then asked the community to evaluate and prioritise the options, with the community determined values in mind. View community survey results.

What was decided?

Following analysis of all the feedback gathered, and combined with a technical multi-criteria analysis, the following five infrastructure options have been shortlisted for a detailed feasibility assessment investigation:

  • Permanent connection between the Coorong South Lagoon and Southern Ocean, including temporary pumping from the Coorong South Lagoon to the Southern Ocean (salinity reset)
  • Targeted dredging of Coorong flow constrictions to improve connectivity
  • Further augmentation of South East Flows to the Coorong (SEFA)
  • Coorong Lake Albert – connector
  • Additional automated barrage gates.

See details on how the decision was made and read the announcement.

Where to from here?

Feasibility investigations will now be conducted for the prioritised options, including combinations of the options. These investigations include but are not limited to:

  • Hydrodynamic, biochemical and ecological modelling
  • Ecological assessments and analysis
  • Engineering technical feasibility assessments
  • Concept designs
  • Social/economical assessments
  • Risk assessments
  • Cost/benefit analysis

Feasibility investigations will help us determine the options that are likely to have the best benefit for the Coorong. For those options deemed feasible and desirable, business case(s) will be developed for consideration by the Commonwealth for further investment, including implementation.

How can you get involved?

We are going to be involving First Nations, local communities and the broader South Australian community at each assessment phase of the project. Find out about current opportunities.

Additional resources

A technical review of previously identified and investigated infrastructure options, including the provision of a high-level summary of each option.

Alongside this, DEW initiated a series of internal workshops to develop a State of the Coorong discussion paper to describe:

  • the current state of the Coorong
  • the potential “do nothing” future state of the Coorong
  • the desired ecological state of the Coorong
  • how we might reach the desired state.

The discussion paper provides a useful introduction and rationale for what long-term management options, like those introduced in this process, might need to achieve.

Ongoing information

To receive Healthy Coorong, Healthy Basin updates and opportunities, including citizen science activities and community consultations, please email projectcoorong@sa.gov.au.

 

Read more about our related priorities