Background

This section seeks to ensure that site planning for any proposed development takes into account the topography, geology, the soils of the site and surrounding land. It also aims to minimise disturbance to existing landforms, costly earthworks and to protect existing and proposed development from becoming unstable.  

Objectives

1. To allow for the construction of retaining walls on sloping land at the subdivision works stage of a development;
2. Minimise cut and fill through site sensitive subdivision, road layout, infrastructure and building design;
3. Minimise additional earthworks of lots during the construction phase;
4. Ensure land forming does not increase the potential for the inundation of water on any other land during the full range of flood events; and
5. Protect and enhance the aesthetic quality and amenity of the area by controlling the form, bulk and scale of land forming operations to appropriate levels.

Controls

General

1. Subdivision and building work should be designed to respond to the natural topography of the site wherever possible, minimising the extent of cut and fill (e.g. for steep land houses will need to be of a ‘split level’ design or an appropriate alternative and economical solution).
2. Subdivision and building work must be designed to ensure minimal cut and fill is required for its construction phase.

Retaining Walls and Engineering works During Subdivision

1. All retaining walls are to be of masonry construction (or the like).
2. All retaining walls proposed are to be identified in the development application.
3. The maximum height of a single retaining wall is 1 metre. A variation to the maximum height may be considered if in Council’s opinion, supporting information adequately demonstrates that the development will not have adverse impacts on adjoining properties and overall local amenity.
4. Where terraced retaining walls are proposed the minimum distance between each step is 1 metre.
5. Retaining walls may be built on the boundary provided that a section 88B instrument is created on the affected lots to support the walls. Retaining walls are to be designed and constructed to allow for installation of boundary fencing without impact on the structural soundness of the retaining wall and its footings.
6. Where retaining walls are not on the boundary the retaining wall and associated infrastructure are to be wholly contained within the allotment.
7. Retaining walls that front a public place are to be finished with anti-graffiti coating.

Steep/Unstable Land

1. Development on land having a natural gradient of 1:6.7 (15%) or greater must not be approved unless a geotechnical study, including guidelines for structural and engineering works on the land, has been considered by Council.

Note: Development on sites with a natural gradient of less than 15% may also require a geotechnical assessment depending upon site characteristics.

Use of Virgin Excavated Natural Material (VENM)

1. All land forming operations should involve the use of clean fill (also known as Virgin Excavated Natural Material or ‘VENM’). The VENM must also meet the same salinity characteristics of the receiving land. Council may consider alternatives to VENM on merit.

Further Information:

Schedule 3 of Environmental Planning and Assessment Regulation (Waste management facility or works)

Council’s Engineering Design Specifications

Protection of Environment Operations Act