This information has been developed to help property owners understand their roles and responsibilities when living in Redland City’s canal and lakeside estates. It includes information on important issues regarding revetment walls and protecting residential amenity, as well as neighbourhood etiquette.
What is a revetment wall?
A revetment wall is a permanent, engineered structure on a lake or canal front that protects an embankment of earth. It is designed to maintain the slope and protect it from erosion. It has a limited life and requires regular inspection and maintenance.
Where are revetment walls located on Redlands Coast?
There are revetment walls in the canal estates of Raby Bay at Cleveland, Aquatic Paradise at Birkdale and the lakeside estate of Sovereign Waters at Wellington Point.
Issues associated with revetment walls
Revetment walls are designed for a specific engineering purpose, so have limited capacity to support additional loading, which may cause premature wall failure.
Because of the significant costs of repairing and maintaining revetment walls, residents should ensure they don’t do anything to undermine their structural integrity.
This includes attaching structures to the wall (e.g. cleats), planting vegetation or installing landscaping materials within nine metres of a revetment wall.
Property owners are responsible for ensuring all development within nine metres of any revetment wall is approved by Redland City Council, which refers developments to other authorities if required, eg. State Government.
How often does Council inspect the walls?
Council does regular on-site inspections and on-the-ground monitoring in all canal and lake estates. In addition, annual aerial surveys are carried out in Raby Bay. These inspections inform annual maintenance and repair activities.
Landowners should also monitor the condition of revetment walls adjoining their properties and report any signs of defects to the Council, which will arrange a site visit in response to any report. This can help prevent further damage and reduce the costs of future repairs.
Setback requirements for revetment walls
To limit revetment wall damage in Raby Bay, Aquatic Paradise or Sovereign Waters, certain types of development on an adjoining canal or artificial water body are assessable, or subject to planning requirements.
This means the development will need to be designed to comply with the standards in the City Plan before it can be constructed, and will require planning approval.
Property owners who wish to carry out work on a house, including decks, gazebos and pools, don’t need planning approval if the structure will be set back nine metres from the property boundary adjoining a revetment wall.
However, work on a house within nine metres of a revetment wall requires planning approval.
The property owner must demonstrate that the development will not have an adverse impact on the structural integrity of the wall. This requires certification from a registered professional engineer.
In addition, visual amenity and the character of the canals are considered in the approval process.
How are canal and lake estate works funded?
Redland City Council has introduced differential rating categories for Raby Bay and Aquatic Paradise canal properties to fund revetment wall repairs in the estates.
Council will contribute 10 per cent of the cost of works on revetment walls at Raby Bay and six per cent of the works at Aquatic Paradise. This reflects the percentage of revetment walls that are owned by Council, which border public facilities such as parks.
Canal and lake maintenance activities like dredging are funded by Council through general rates.
Who is responsible for managing revetment wall and canal/lake maintenance?
Council manages the canal and lake maintenance programs, including dredging and revetment wall repairs. This provides residents with assurances that revetment walls will be fixed should problems arise, and any repairs will be of a high standard.
How are revetment walls maintained at Sovereign Waters?
Historically, there is no or limited revetment wall work needed in Sovereign Waters. In the event of an emergency, Council would carry out any emergency work required.
Differential rates could be introduced in future for revetment wall repairs in these estates if required; this will be determined by Council’s annual operational and capital works programs.
Dredging is not needed at Sovereign Waters either because there has been no build-up of silt.
Why does Council manage revetment wall maintenance?
It was decided that Council will continue managing revetment wall maintenance following city-wide community consultation in 2018 with residents and the city’s first Citizens’ Advisory Panel.
Council listened to representatives from the Raby Bay Ratepayers’ Association and others who wanted Council to continue to manage revetment wall repairs.
With Council managing the maintenance, there is an assurance that repairs will be completed to a high standard if required and not left to individual property owners’ discretion.
What can property owners do to prevent damage to revetment walls?
In addition to regular maintenance inspections by Council, property owners should ensure that revetment walls are not inadvertently damaged, i.e.:
- avoid placing landscaping materials such as pavers, sleepers and fill near the revetment wall
- don’t plant vegetation, particularly trees, close to the wall
- don’t attach any fixtures to the revetment wall, including cleats, ropes and rails
- don’t modify the revetment wall in any way, including removing the rocks (e.g. to establish a jet ski dock)
- inspect your pool or irrigation systems for leaks
- ensure pool overflows and roof water drainage is directed to the street drainage system
- ensure landscaping improvements do not concentrate storm water flows over the wall, as this can scour the canal bank, particularly at low tide.
For further advice about building near revetment walls, please call Redland City Council on 07 3829 8999 and ask to speak to the Engineering and Environmental Assessment Team.