The role of green and blue infrastructure in supporting liveability, including cooling urban spaces, requires clear and consistent acknowledgement. Green and blue infrastructure includes natural, managed and constructed green spaces, waterways, wetlands, lakes and marine environments.

It plays a vital role in supporting liveability by having a positive impact on health, productivity, culture, ecosystem services and property values. Importantly, it also cools urban spaces, a role that must be considered in land use planning and infrastructure plans.

Cooling makes Australia more liveable as it mitigates extreme heat, a complex stress that can trigger shocks. Extreme heat kills more Australians than any other natural stressors.52 An estimated 2% (36,000) of total deaths were associated with heat between 2006 and 2017.53

The impact of heat on Australian cities is expected to continue growing due to our changing climate, the urban 'heat island' effect (where an urban area is warmer than the surrounding environment) and changing settlement patterns.

Responsibility for addressing extreme heat in urban design and designing, delivering and maintaining green and blue infrastructure sits across state and territory governments, local governments and the property industry. Collaboration will be necessary to ensure a nationally consistent approach and realise the liveability and health benefits.

What should governments do?

Green and blue infrastructure should be categorised as an asset class and an agreed methodology developed to quantify the benefits it delivers. The methodology should also consider costs, including ongoing maintenance costs to enable resourcing.

Addressing extreme heat and promoting and protecting green and blue infrastructure must be embedded as objectives for strategic planning. These should also be codified in regulations, building and design codes and standards.

Green and blue infrastructure should be prioritised as a risk mitigation and adaptation intervention, with targets for reducing extreme heat in urban areas by increasing or maintaining green and blue infrastructure.

There also needs to be a consistent approach to developing high-quality data:

•  Data on the quantity, quality and spatial distribution of green and blue infrastructure should be analysed to identify the baseline performance of places during heatwaves.

This can help develop priorities, enable monitoring and progress evaluation.

•  Performance data should identify the people and places most exposed to extreme heat, including the health status, demographic structure and vulnerability of local populations. This will create a map of where heat and community vulnerability intersect.

For more information about measuring the economic impact of green and blue infrastructure, see the Social infrastructure chapter.