2022-23 River Murray flood event
The 2022-23 River Murray flood event occurred between November 2022 and February 2023, as a result of heavy rain and flood events interstate.
This flood event was the largest since 1956, and the third highest flood ever recorded in South Australia, with an unprecedented number of impacted homes, shacks businesses and infrastructure.
The flow rate at the South Australian/Victoria border peaked at 186GL per day on 22 December 2022, with approximately 4,000 hectares of agricultural land and 3,500 private residences affected over the course of the event.
River Murray flood information and maps
Where can I find information to help me with flood recovery?
You can find a range of information and links for flood recovery assistance on the State Government'scentral website.
What is the current and forecast flows and water levels for the River Murray?
The latest flow information is available on the Flows and daily water levels webpage or view the weekly River Murray Flow Report.
Are there any maps available that show where flooding has occurred?
No, however DEW’s online Flood Awareness Map is available for the community and shows the inundation areas that were expected at a range of flows.
How do I receive updates on river flows?
You can keep up to date on SA River Murray flow rates, water levels, barrage operations, navigation issues and construction activities by subscribing to, or accessing current and previous issues of, the SA River Murray Flow Report.
The public are encouraged to regularly check the SA Government Recovery website and the South Australian State Emergency Service Service (SES) website, which includes information on current warnings, with near real-time information.
Levee banks
Levee recovery updates
For updates on the status of levees, visit the dedicated Lower Murray Reclaimed Irrigation Area (LMRIA) levee banks page.
What happened to levees during the 2022-23 River Murray flood event?
The Government of South Australia maintains a number of agricultural levee banks along the Lower Murray, between Mannum and Wellington. There are also a number or privately owned levees.
There are 26 irrigation areas (involving 142 landholders) that support agriculture production in the LMRIA. These agricultural levees were constructed to contain water within the main river channel, to reclaim land for agricultural activity and to house irrigation infrastructure.
While these levees provide some flood protection by withstanding flows equivalent to those experienced during the 1974 flood, it is not their primary purpose, and they can only perform their role up to their design level, above which, they are likely to overtop (when water levels exceed the levee crest elevation and flow into the area behind).
During the 2022-23 River Murray flood event, 20 of these areas were inundated and required assistance to dewater and recover.
It’s important to note that only 2 levees were breached during the 2022-23 flood event, the rest were overtopped.
The Department for Environment and Water (DEW) and Department of Primary Industries and Regions South Australia (PIRSA) worked closely with trusts and landholders to stabilise and dewater levees, and return agricultural land to production as soon as possible.
DEW proactively engaged the assistance of independent consultants and subject matter experts, to advise on safe and appropriate methodologies for stabilisation and consultation with the community.
What assistance is available?
Primary producers impacted by the River Murray flood are encouraged to access the Primary Producer Recovery Grants and the Primary Production Irrigation Grants along with other services.
For more information visit www.pir.sa.gov.au.
Is there a guide for earthen levee embankment inspection and repairs?
An 'Earthen Levee Embankment Inspection and Repair Guide’ has been developed to assist councils and landholders with the inspection and repair of levee embankments. It is not intended to replace expert advice and it is recommended that landowners obtain advice from an experienced levee embankment or dam engineer, or other relevant expert.
Now that the flood event has passed, is it safe to access government owned levees?
While flood recovery works are taking place, levee banks along the Lower Murray from Mannum to Wellington are closed to the public for recreational activities. This includes for walking, fishing and mooring of river vessels.
To ensure the safety of yourself and others, you should not:
- enter or remain on an engaged levee except as provided for an emergency response or inspection, maintenance, and repair (including inspection, maintenance and repair of the levee, power lines or other infrastructure).
- moor, anchor, attach, or secure any vessel to an engaged levee.
- operate a vessel on the River Murray exceeding a speed of 4 knots within 250 metres of an engaged levee.
Local Irrigation Trust members and contractors will have continued access for inspections, maintenance, and emergency repairs. Members are encouraged to take all necessary precautions when working on the levees.
As privately owned levees along the Lower Murray are managed and maintained by private landholders, access to their levee banks may be closed at the discretion of the landholder.
Waste disposal stations
Are River Vessel Waste Disposal Stations still closed?
As at 7 July 2023 all River Vessel Waste Disposal Stations (excluding Lock 3) are online and operational. Additional minor repair works will be required across the stations over the next couple of months. This is expected to have a minimal impact on the operational status of the stations.
The Lock 3 River Vessel Waste Disposal Station has been out of commission since January 2020 due to a significant infrastructure failure. The nearest alternative waste facility is located at Waikerie. Normal boat waste (domestic or galley waste) can still be deposited at the Lock 3 facility at the present time.
Please report any River Vessel Waste Disposal Station issues on 1800 799 065.
If you have any questions, please contact the DEW Engagement Team on DEW.WIOCommunications@sa.gov.au
Managing River Murray locks and weirs in South Australia
How were River Murray locks and weirs managed during the 2022-23 floods?
SA Water operates the locks and weirs in South Australia on behalf of the Murray-Darling Basin Authority and in consultation with DEW.
During periods of normal river flow, the locks and weirs are operated to maintain relatively steady upstream water levels for irrigation, water supply and navigation.
During high flow and flood events it is not possible to operate the locks and weirs, so stop logs and navigation passes are removed. This allows the increased river flows to pass through, to ensure that there is no damage to the infrastructure, which is reinstated as the flow returns to normal operating conditions.
During November 2022, all relevant weir sections were removed at all of 6 locks and weirs on the River Murray in South Australia as water levels increased. As the flows continue to recede they will be reinstated to assist in regulating the water levels once again.
Given we knew the flood was coming well in advance, why weren’t the water levels in the weir pools reduced to provide capacity for the increased flows?
During the 2022-23 flood, lowering the weir pools would have made very little difference to reduce the risk of flooding due to the significant volumes of water that came from upstream parts of the catchment. In normal conditions, the flow ranges at the South Australian border are generally between 3 GL/day to 10 GL/day depending on the time of year.
Flood protection works undertaken by property owners
Do I need approval to remove temporary flood protection measures undertaken prior to and during the flood event?
DEW supported temporary flood mitigation measures on Crown land to assist in protecting infrastructure and assets from the River Murray flood waters. Temporary measures included the construction and/or use of sandbags, water bladders or plastic sheeting.
Now that flood waters are receding and when safe to do so, temporary flood mitigation measures can start to be removed. Should removal involve earth disturbing activities or the removal or introduction of soil or fill to remediate the land, permission may be required from DEW prior to commencing. This ensures
- activities do not impact sites of cultural significance and native title
- appropriate approvals can be obtained such as development approval and
- works undertaken on Crown land is not detrimental to the environment and communities.
Emergency provisions were implemented for temporary flood mitigation activities. Should any of temporary measures now be considered permanent, retrospective approval for these works will be required. Those seeking retrospective approval should discuss their proposal with DEW’s Crown Lands Program and their local Council.
Retrospective approvals are an important part of recovery and remediation. It ensures permanent flood mitigation measures are appropriately constructed and fit for purpose, and do not have a negative impact on the environment, adjoining neighbor's property and the community.
How do I ensure my activities do not impact on Aboriginal Heritage located on Crown land?
Land surrounding South Australia’s waterways and rivers are of high importance to Aboriginal people and their communities and often contain material from the activities of elders and descendants.
Native Title rights continue to exist and land adjacent the River Murray and within its floodplains hosts numerous culturally significant sites, some dating back as far back as 40,000 years.
It is important that any activity occurring along the River Murray does not adversely impact on these sacred sites that are of high value to Aboriginal people and their communities.
For further information please visit the DEW website for Crown lands.
What if my infrastructure was damaged by the flood event or receding flood waters?
Should you have experienced any damage as a result of rising or receding flood waters, if it is safe to do so, you should make immediate attempts to secure your infrastructure to assist in preventing any further damage to it along with other structures and/or visitors within the vicinity.
Your insurance company will be able to assist with repairs and/or removal of the damaged infrastructure.
Should an emergency situation arise as a result of infrastructure located along the river you should call 000 for life threatening situations or SA State Emergency Service on 132 500.
Environmental benefits
What was the environmental benefits for the River Murray channel and floodplains
High flows are important for native fish spawning, bird breeding and plants thriving.
This flood event has provided much needed water to areas of floodplain that have not received water for over 60 years. Black Box woodlands and other native vegetation that have been struggling in recent years will receive a much-needed boost.
When stressed lignum shrublands and red gum and black box woodlands receive water, it improves the condition of the plants which in turn provides better feeding and breeding habitats for many species of frogs, fish and birds.
Reconnecting the floodplains and wetlands to the main river will allow plants and animals to move throughout the new areas. Temporary habitats created by the floodwaters provide habitat for many species of birds, frogs and invertebrates. Connectivity also supplies organic matter and nutrients to the river system, which increases productivity and the transfer of energy up through the aquatic food web.
Higher flows also stimulate or support breeding by native fish species such Murray cod, silver perch and golden perch, and will improve the chances of successful recruitment by improving habitat availability and food resources.
What were the environmental benefits for the Coorong, Lower Lakes and Murray Mouth
The Coorong, Lower Lakes and Murray Mouth form an internationally significant Ramsar listed wetland, which continues to recover from the impacts of the Millennium drought.
This flood event will had great benefits for this part of the river system. The flushing flows have helped scour out the Murray Mouth halting the need to dredge for a period of time. Flow through the Murray Mouth is important to flush salt and pollutants from the entire river system and keep water levels and salinity in the Coorong at healthy levels.
It will also support habitat for native frogs such as the southern bell frog, small-bodied fish such as the southern pygmy perch and boost invertebrates that are food for wetland birds.
