Riverbank collapse more likely to occur during times of low water in the lower River Murray. Riverbanks can be extremely sensitive to erosion and other soil effects. ‘Slumping’ is where a section of riverbank suddenly gives way, taking with it trees and whatever else is on the bank at the time. Slumping incidents have caused problems in some areas of the Murray in recent years.
Riverbank erosion can be caused or affected by natural actions like wind and wave action, heavy rain or soil cracking in the heat, but boating can also have an effect by raising wake and wash and stirring up sediments.
Reporting riverbank collapse
If you need to report signs of riverbank instability please contact the local council where it has occurred.
Signs of riverbank collapse are not always obvious so it's important to be aware of the risks and exercise caution at all times.
To spot a riverbank collapse, look for these signs:
- Cracking in the riverbank - both deep and shallow cracks are likely signs of bank instability and the area should be avoided on foot, in vehicles and by boat.
- Leaning trees - trees, including willows and gums, leaning towards the river can be a sign of bank instability.
The root systems of these trees are weakened by the unstable soil and their weight puts pressure on the riverbank.
- Bubbling in the water can be an indicator of soil movement below the water surface, and hence instability.
- Fencing and warning signs have been used where there has been a visible collapse, or where there is known potential for collapse or erosion. Please observe these measures and do not enter these areas.
- Steep riverbanks with deep drop off to deep water are considered to be at particular risk of collapse.
- Carry extra lengths of rope so you can secure your boat to trees set further back from the river's edge.
- Be aware that in areas where riverbank collapses have occurred, there may be submerged materials, including trees.
- Observe all warning signs and fencing put in place for public safety.
- Moor to trees close to the river's edge where weakened roots may not support boat weight.
- Approach areas by boat that have already collapsed or are identified as having the potential to collapse.
- Park vehicles, camp, picnic or walk on riverbanks where cracking is visible.