Subdivision design for a sustainable future

What’s included in this fact sheet:

EcologyThis fact sheet explains how subdivisions can retain and enhance ecology by responding to, protecting and improving the biodiversity within a development plan or subdivision site.

Although the existing conditions on any new greenfield subdivision will vary, the subdivision process should aim to retain and enhance the natural environment as much as possible. This will not only provide a positive environmental outcome, but offer significant liveability benefits to residents and capture the economic benefit of healthy ecosystems.

These benefits are known as ecosystem services. Key ecosystem services include: habitat for wildlife, urban temperature regulation, runoff mitigation, food supply and recreational and aesthetic benefits.

The cooling effects from trees has been shown to reduce the need to cool homes and provide comfort in public places, even during extreme heat.

Enhanced ecology begins with the subdivision design process. By assessing existing conditions, recognising existing natural features and biodiversity, the design process can then seek to protect and improve them.

Natural features include existing trees, areas of native vegetation (that might include grasses and shrubs, not just trees), waterways and wetlands, wildlife habitat such as rocky outcrops, logs and fallen timber. In some case man made features, such as dams, might also be considered valuable for biodiversity.

Why do subdivisions need to retain and enhance ecology?

Benefits of retained and enhanced ecology

What should be considered to improve ecology

• Canopy cover• Biodiversity conservation• Enhance biodiversity value

Where can I find out more?

Benefits of retained and enhanced ecology

Why do subdivisions need to retain and enhance ecology?

Sustainable Subdivisions Framework7 Key Sustainable Subdivision Categories 4.0

Developers can take advantage of:• Enhanced market appeal of the

subdivision to prospective purchasers• The economic benefit of ecosystem

services• Demonstrating best practice

environmental management and creating climate resilient neighbourhoods

A new resident can expect:• Improved comfort with a cooler surrounds• A healthy urban environment that supports

local wildlife• The opportunity to interact with nature in

your immediate neighbourhood

Where can I find out more?

Large canopy trees are a key contributor to urban cooling however, also benefit the overall biodiversity value of the site.

Canopy cover objectives include:• To provide lots with areas and

dimensions that enable the retention and establishment of trees

• To promote early delivery of medium and large trees

With targets for projected canopy cover at 15 years set at 25% for the public realm, ensuring that trees can establish within the subdivision is key. This includes ensuring integrated water management provides trees with adequate access to water, particularly as they are establishing.

This first step to enabling large canopy trees is to design around existing mature trees and implementing tree protection measures during construction.

Accelerating the process of planting medium and large trees, will ensure that even the first residents will have improved amenity and access to significant greening.

Other Fact Sheets in this series are also available to provide guidance on the 7 Sustainable Subdivision Categories. For further information on Ecology, see the Fact Sheets entitled:• Streets and Public Realm• Integrated Water Management• Urban Heat

Sustainable Buildings Fact Sheetsimap.vic.gov.au

Rating ToolsGreen Star Communitieswww.gbca.org.auEnviroDevelopment: www.envirodevelopment.com.au

Sustainable Infrastructure GuidelinesProvides alternative design and construction initiatives to achieve greater sustainability outcomeswww.designmanual.com.au

DISCLAIMER: This Fact Sheet has been created for general information purposes only. While the Fact Sheet has been created with all due care, no warranty is given as to its suitability for any particular purpose and users should obtain their own advice relevant to their situation and specific needs. This Fact Sheet has been created with thanks to IMAP who have developed the Fact Sheet series for the SDAPP (Buildings) Framework.

Canopy cover

Enhancing Ecology in Subdivisions

Biodiversity conservation focuses on ensuring that existing flora, fauna and habitat within and in close proximity to the subdivision is protected. It also considers how biodiversity will be maintained through the life of the subdivision.

Biodiversity conservation objectives include:• To protect, retain and enhance native

vegetation and habitat over the long term• To promote a best practice and

risk management approach to the management of biodiversity assets which aims to avoid or minimise environmental degradation and hazards

• To ensure consistency with any native vegetation precinct plan

Effective biodiversity conservation requires an effective implementation pathway including maintenance plans, biodiversity management plan and adequate tree protection zones through the construction.

Developing and implementing programs to increase resident involvement in biodiversity asset maintenance will also support biodiversity conservation.

Biodiversity conservation

Enhance biodiversity value

Considering how the siting and design subdivisions can minimise the impact on the natural environment from the outset will enable the subdivision design to retain and enhance ecology while also setting the conditions for this to be maintained and enhanced through the life of the subdivision.

A subdivision design and construction needs to do more than protect existing biodiversity. It should also outline key strategies to increasing or enhancing biodiversity value.

Enhancement of biodiversity value objectives include:• To promote the creation of habitat

corridors and movement of flora and fauna • To avoid the planting and spread of

environmental weeds• To promote the delivery of any vegetation

offsets locally to the subdivision

Strategies to enhance biodiversity include using native species in landscaping, layering of plantings to create diversity of habitat and novel habitat creation such as hollow creation for birds and mammals.

These strategies combine to create high species diversity, connections between key ecological assets and ensure that streets, parkland and environmental buffers to waterways are optimised to deliver the full range of ecosystem services including recreation, food production and place value - the key to liveability.