Upzoning scenario modelling

In 2013, the NSW Government rezoned the Austral and Leppington North Precincts to enable 17,350 new homes in the South-West Growth Centre. Planning controls encouraged higher housing density, with infrastructure designed for the original target. However, smaller lot sizes (now averaging 300m²) have increased capacity to 25,000 homes, straining resources.

Amid Australia's housing crisis, the precincts aim to support the National Housing Accord by enabling additional homes with matching infrastructure for sustainable growth. This project quantified the capacity of potential future upzoning and produced alternative population, household and dwelling forecasts along with key demographic indicators with which Liverpool City Council could accurately plan for infrastructure needs to 2041 and beyond.

How .id helped?

Our analysis for this project included:

• Micro-area residential development sequencing: Using our recently updated small area residential development assumptions from our National Forecasting Program, we were able to map out where development will occur within the Austral and Leppington North Precincts, when and at which rate of development.
  

  
  Development sequencing of the Austral and Leppington North Precincts

  
  
• Demographic composition of Austral and Leppington North: Calculating the future population, households and dwellings totals in Austral, along with characteristics such as average household size and dwelling occupancy rates, for each year from 2021 to 2041, and at ultimate buildout.
  
  
• Creation of an upzoning residential development scenario: In order to understand what impact a density upzoning would have on Austral and Leppington North Precincts' future population, capacity and therefore, infrastructure needs, .id was able to quantify potential yield from upzoning of a segment of Austral, when this scenario would realistically occur and how different the scenario would look (from a population, households and dwellings total, as well as average household size and occupancy rates) in the future.

The preparation of information for use in this project also required an update of residential development assumptions to ensure accurate residential development rates were assumed for 2024 and 2025. This was important, as rates of dwelling construction and completion have slowed down and a detailed verification was necessary.

Next steps

The output from this project allows Liverpool City Council to meet the broader project objective to identify the additional infrastructure and services required to unlock greater housing capacity within the Austral and Leppington North Precincts.

The Liverpool City Council also aims to support thriving and sustainable Western Sydney communities into the future, and the information provided is highly valuable and vital.

Scenario modelling as a means of testing your possible futures

.id has an in-depth knowledge of communities across Australia. Our National Forecasting Program is an up-to-date nationwide forecast, at micro area level, which provides a view of future population and housing growth and is backed by robust assumptions and expert knowledge of Australia.

However, sometimes organisations such as Councils need to test what impact a certain scenario, such as:

• The upzoning of an activity centre,
• Changes in policies which result in higher identified housing capacities,
• The release of more land currently not zoned as residential or
• Potential impact of economic drivers of future population growth. 

This is where .id can utilise our rich and detailed information and expertise in order to quantify and describe those scenario outputs with proven, detailed and robust scenario modelling analysis.

Work with us

We see a lot of potential for our scenario modelling capabilities. While we are actively contacting our customers to explore how we can help them understand future scenarios better, we also invite you to contact us if you have any project needs similar to ones described in this case study, or others where our scenario modelling methods could apply.

If you are interested in similar work, feel free to reach out at demographics@id.com.au or on +61 3 9417 2205.