This online engagement was hosted on YourSAy from 23 August to 31 October 2019. Below is a record of the engagement.
We have identified four target areas and priority actions:
- On-ground works
- Scientific trials and investigations
- Water resource optimisation
- Investigation of long-term infrastructure options.
Recognising the need to avoid the permanent loss of ecological values, the government will work with scientists, First Nations and the local community to implement a series of ‘no-regrets’ on-ground actions that address immediate threats to the Coorong.
Actions, which aim to improve the availability and quality of waterbird habitat while the longer-term rehabilitation of the Coorong is undertaken, will include:
- restoration of priority aquatic plants that provide habitat and a food source for fish and waterbirds
- physical removal of filamentous algae
- enhanced management and/or restoration of wetland habitat within the Coorong and Lower Lakes region, and potentially the South East, to provide an immediate refuge for Coorong waterbird species.
In addition, modifications to irrigation system offtakes between Lock 1 and the barrages that enhance operational flexibility for the delivery of environmental water to the Coorong will be pursued.
All on-ground works will be designed and delivered to have low impact on the surrounding locations and foster partnerships with First Nations and the community.
Scientific trials and investigations
Through years of monitoring and research, we have built a good understanding of the Coorong and its role in supporting a unique diversity of fish, plants and waterbirds.
However some elements of the Coorong have now undergone a number of long-term changes and a number of new threats to the system present novel management challenges for which we need to find solutions.
It is important that work to restore a healthy Coorong is based on the latest science.
Trials and investigations will be designed to fill key knowledge gaps and provide the scientific evidence-base to inform what management actions might be required to:
- reduce nutrient loads and algae abundance in the Coorong
- switch the South Lagoon back to an aquatic plant dominated system rather than an algal dominated system
- provide the food resources that are required to support waterbirds and fish populations
- increase the abundance and distribution of waterbird populations at local and regional scales within the Coorong
- identify the adaptation pathways that are required to ensure that the ecological values of the Coorong are maintained into the future under a changing climate
- incorporate cultural knowledge and values of the First Nations into decision-making.
Water resource optimisation
Providing water to the Coorong is vital for restoring its ecological values. To improve certainty that the delivery of water to the Coorong will achieve its intended purpose, sophisticated forecasting and modelling tools are necessary. These tools allow site operators to effectively plan and manage the use of water for environmental purposes and ensure that the water available is used in an efficient manner.
Healthy Coorong, Healthy Basin proposes developing:
- a hydrological forecasting model to enable short and long-range scenario testing
- a Management Action Database to coordinate the storage and retrieval of vital water management information.
For these tools to be accurate and empower water managers to use water effectively and efficiently, they need to be informed by targeted monitoring.
Targeted monitoring, which will also help evaluate on-ground actions, will include:
- extensive water quality sampling
- improvements to existing Coorong monitoring stations
- Coorong flow gauging and bathymetry assessments.
Investigation of long-term infrastructure options
The hydrology of the Coorong, Lower Lakes and Murray Mouth system has been dramatically altered. 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. The current tools available to manipulate flows and water levels in the south lagoon include:
- River Murray environmental flow provisions
- barrage operations
- Murray Mouth dredging
- flows from the South East.
Additional management options may be required, particularly in the face of climate change.
A number of potential major infrastructure and management options have been identified over the years to potentially improve water delivery to, and enhance the ecological health of, the Coorong.
Noting the close engagement with First Nations and community that will need to occur, the Healthy Coorong, Healthy Basin project will assess the technical feasibility and the environmental, social and cultural benefits and impacts of long-term management solutions to improve flows to the Coorong.
Options to be consulted on, and potentially investigated to feasibility assessment, could include:
- a connecting pipe or channel between Lake Albert and the Coorong to improve environmental water delivery to the Coorong
- improvements to connectivity between the North and South Lagoons and the Lower Lakes
- options to maintain an open Murray Mouth, mitigate the need for dredging and provide greater seawater exchange with the Coorong
- augmenting the South East Flows Restoration Project with additional water from the South East that currently flows out to sea
- options to regulate and maintain water levels in the Coorong South Lagoon.
In addition, consideration will be given to ‘up-scaling’ management options from the scientific trials and investigations and ‘no regrets’ on-ground works.
For those long-term operational infrastructure options deemed feasible, business cases will be developed to support their implementation under the Healthy Coorong, Healthy Basin investment, or future funding.
Download the Healthy Coorong, Healthy Basin Action Plan.