Retaining walls raise questions

Guidelines to establish consistent designs and character in new housing estates for Warragul and Drouin will include new rules for retaining walls.

The draft Warragul and Drouin Design Guidelines, prepared by Tract consultants, has been presented to Baw Baw Shire ahead of a six week community consultation period.

The detailed document includes guidelines for building and landscaping requirements on slopes, neighbourhood character and interface treatments between agricultural and residential developments.

When adopted, the guidelines will apply to new housing developments and infill residential developments.

A section of the report – slope design guidelines – focuses on addressing challenges to design new houses to respond to sloping land and avoid the need for substantial retaining walls.

The report stated 37 per cent of urban growth land in Warragul was categorised as steep or very steep sloping land. In Drouin it’s 18 per cent.

Steep land is classed as a 10 to 15 per cent gradients while very steep is 15 to 20 per cent.

“These areas will require careful design to ensure attractive neighbourhoods are delivered with a level of amenity for residents,” the report said.

The draft report states the guidelines aim to “ensure retaining walls do not dominate streetscape and views to new residential areas.”

Under the proposed guidelines, developers or property owners will be required to provide a slope management plan.

The guidelines address street layout and design of subdivisions; lot and building design; and, earthworks and retaining walls.

If adopted, retaining walls will be restricted to one metre high.

The draft document states where more than one retaining one is required they should be staggered with a minimum of one metre distance between each stagger to allow for landscaping.

The guidelines state retaining walls over one metre “should be avoided” and will require a building permit.

Landscape guidelines also are proposed to “reduce the visual impacts of roofing, fencing and retaining walls by allowing trees to be visible between dwellings.”

The draft guidelines also outline preferred lot sizes depending on the slope gradient with 450 to 600 square metre lots preferred in steep areas and 600 to 750 square metre lots preferred in very steep areas.

Lot sizes on extremely steep slopes (more than 20 per cent gradient), where split level excavation is recommended, should be more than 550 square metres.

“Where extensive retaining walls are required in new estates, they should be installed by land developers to provide a cohesive treatment for retaining walls across streetscapes,” the report states.

During an open community briefing on the draft design guidelines last week, Jana Group consultant project manager Jayman Prestidge asked if engineers had reviewed the ability of developers on steep and very steep land being able to achieve the recommended precinct structure plan yields.

He said on properties where all land had more than a 10 per cent slope, they suspected this would be difficult to achieve.

“If yield cannot be achieved on steep and very steep land how will council respond to applications?

“Some of these changes appear to be already being applied (with evidence as early as September 2020) to existing developments and applications.

“There must be transitional requirements for existing developments to pivot to new,” Mr Prestidge said.

Developers, who did not want to be quoted by The Gazette, also complained that new guidelines were already being imposed.

The Gazette was told a residential development in Waterford Rise, Warragul had been suspended because of a dispute over earthworks and retaining wall provisions.

But, planning and development director James Reid said guidelines, once adopted as part of a planning scheme amendment, would only apply to new applications.

He said the guidelines had not been enforced on existing subdivisions.

“The Warragul and Drouin Precinct Structure Plans, both introduced in 2014, contain requirements and guidelines that apply in relation to retaining structures on public and private land. It is these provisions that council officers have been applying in recent assessments,” he said.

Mr Reid said council was aware that site preparation works on a future stage of Waterford Rise were on hold.

“The decision to commence and later suspend those works is a business decision of the developer.

“Council is currently assessing detailed engineering plans for the relevant stage. This assessment is being based on the existing endorsed plans for Waterford Rise and the current PSP provisions.

“The proposed retaining wall guidelines are not being used in this assessment,” Mr Reid said.