Retaining walls
A retaining wall is a wall that holds back or supports soil when the natural ground level has been altered. When a person ‘cuts' into the natural ground level, the soil on the high side is to be prevented from collapsing with the use of a retaining wall.
Alternatively, when a person ‘fills' or provides extra soil where the natural ground slopes downwards (to make it level), then the additional fill needs to be prevented from moving further down the slope. This again is achieved with the use of a retaining wall.
Most commonly, retaining walls are required between neighbours who build on sloping sites.
Responsibility for Construction
The owner who alters the natural lie of the land is responsible to provide a retaining wall. However, where both property owners alter the land, they would be considered jointly responsible. The sharing of costs for the retaining wall is a civil matter that must be negotiated between neighbours.
Council has no authority to act in boundary disputes between neighbours.
If you are unable to reach agreement on any proposed work, contact the Legal Services Commission of South Australia for civil advice.
Location of Retaining Walls
Should only one property owner require a wall to be built on a boundary, the retaining wall itself must be entirely on one side with only the outside face of the wall on the boundary. Alternatively, if both neighbours share in the construction of the wall equally, the retaining wall should be built straddling the boundary.
Is Council Approval Required?
A development application for a retaining wall is only required to be submitted to Council for assessment where the height of the retaining wall is one (1) metre or greater.
However, note that when the combined height of a retaining wall and fence exceed 2.1m in height, development approval is required – see information on Fencing.
Where approval is required, Council will seek to minimise the visual impact of retaining walls and fencing, especially when viewed from neighbouring sites or the street, while balancing visual privacy expectations for occupants.
The documents to be provided to Council for approval should include:
- a detailed site plan indicating the location of the wall
- elevation drawings showing materials, finishes and height of the wall
- construction details of how the wall will be constructed
- engineer's design documentation including calculations for the footings and connection details
Easements
Building work is generally not permitted over easements. If you need to construct a building over an easement, approval must be obtained from the authority that has control of the easement. The Certificate of Title will detail which authority has the benefit of the easement.
To obtain a copy of your Certificate of Title, visit Land Services SA - Get a copy of your Title | Land Services SA