Constraints measures project
The South Australia Constraints Measures project is removing constraints, or barriers, to the delivery of environmental water, in order to improve the health of the South Australian River Murray’s floodplains and wetlands.
In 2013, the Constraints Management Strategy was produced by the Murray-Darling Basin Authority to identify the physical, operational and management constraints that are affecting delivery of water for the environment for 7 key areas across the Basin, including the River Murray in South Australia.
While the main goal of relaxing constraints is to provide greater scope for environmental flows to floodplains and end-of-system, the SA Constraints Measures project will also improve access to the river and facilities for water managers, communities and landholders during natural high flow events.
High flow events that enable flows over riverbanks are beneficial for the environment because they connect habitats along the floodplain with one another and the main river channel. Such connections enable species to access refuge habitat areas, find breeding partners, and recolonise suitable habitats, all of which are important for the species’ long-term survival. Flooding also increases food resources for species downstream of the flood location.
River regulation and water use for consumptive purposes have significantly altered the flow regime of rivers across much of the Murray-Darling Basin, reducing the volume and duration of high flow events. This has resulted in flow volumes greatly reducing, with the average annual flow volume now less than half the volume prior to development. Similarly, the length of time between high flow events has grown to more than twice that experienced prior to regulation and diversion of river flow.
Benefits to South Australia
Delivering water for the environment will enable high flows to reach floodplains on a more regular basis, which will aid environmental outcomes for South Australia. The SA Constraints Measures project aims to remove some of the constraints, or physical barriers, impacting the delivery of water for the environment in the South Australian River Murray.
Research shows that South Australia will benefit from having coordinated flows of up to 80,000 megalitres per day (ML/day) at the border for periods of one month, up to 3 times a decade. This flow is below the levels observed in 2016 (95,000 ML/day) and well below the 2022-2023 (190,000 ML/day) and 1956 (341,000 ML/day) flood levels.
Planning controls developed as a result of the 1956 flood event have guided the construction of infrastructure on the floodplain to minimise impacts of future high flows and flood events. However, during high flows, inundation of some riverfront land, jetties, banks, marinas, pontoons and public roads can occur.
The SA Constraints Measures project has investigated ways to mitigate the effects of high flows on infrastructure and communities, and additional strategies such as providing more culverts and upgrading roads, riverbanks, walls, boating and marina infrastructure have been considered in order to improve access for communities and landholders during natural high flow events.
High flows are not floods, however, individual property owners should prepare for high flows to minimise impacts to their land and infrastructure. Information and advice on high flows can be found on the River Murray Flows page.
What are we doing?
The SA Constraints Measures project is working to remove a range of barriers currently impeding environmental flows. This includes developing a government framework to support the management of environmental water delivery and an on-ground works program to remove physical barriers inhibiting environmental water from reaching the floodplains and wetlands.
The SA Constraints Measures Early Works project includes infrastructure upgrades that will contribute to building community resilience. The Early Works project is part of a package of initiatives that make up the Murray-Darling Basin Authority’s Sustainable Diversion Limit (SDL) Adjustment Mechanism.
The Department for Environment and Water has worked closely with stakeholders and members of the community on the Early Works project, to understand their priorities and needs and to identify infrastructure options that can be constructed as part of the SA Constraints Measures Early Works project.
The following works are now underway as part of the Early Works project:
- Channel clearing to improve flow and connectivity across Murray River National Park floodplains at Katarapko.
- Installation of gates and signage in the Murray River National Park at Chowilla and Morgan, to improve visitor management and safety during high flow periods.
- Modernising the Noora pipeline and Renmark Area Drainage Discharge Scheme (RADDS) infrastructure to reduce the risk of failure during high flow events and improve saline groundwater management.
- Upgrading surface water monitoring stations to ensure critical water flow, height and salinity monitoring during high flows.
- Detailed design of cultural facilities at Ngaut Ngaut Conservation Park.
- Upgrading infrastructure on the Loxton riverfront, including 3 toilet blocks, 3 sluice gate upgrades, bank stabilisation and upgrading the Community Waste Water Management System switchboard.
- Design of bank stabilisation at Pomberuk/Hume Reserve in Murray Bridge.
- Detailed design of upgrades to the Swan Reach boat ramp, South Punyelroo Community Waste Water System and roads in the Scott Creek shack area.
- Construction of a house boat mooring at Bowhill.
- Infrastructure improvements at Central Irrigation Trust drainage outlets to improve safety for workers managing irrigation infrastructure during environmental high flow events.
- Detailed design of upgrades to the Renmark rowing dock, Lock 5 marina and 21st Street Bridge.
These works are scheduled for completion by 30 June 2024 and will follow the below timeline.
Enhanced Environmental Water Delivery
The SA Constraints Measures project is closely aligned with the Enhanced Environmental Water Delivery project (EEWD). While the SA Constraints Measures project is focused on increasing regulated flow limits across the Southern Basin by mitigating third-party impacts, EEWD is concerned with developing tools and strategies to ensure river operators and environmental water holders can use this increased operational flow range effectively.
More Information
Fact Sheets
Contact us
Contact the SA Constraints Measures team at DEW.WIOCommunications@sa.gov.au
The South Australia Constraints Measures project is being delivered by the Government of South Australia and funded by the Australian Government, as part of the Murray-Darling Basin Plan.
Image gallery
