Penrith, Australia

Image by Penrith City Council

Sustainability and Resilience

What efforts have been made to reduce the carbon footprint of the initiative?

As part of Council’s sustainability work, the organisation has goals and targets to reduce our carbon footprint.

Within the Cooling the City program, this has been demonstrated by the design of the Jordan Springs Community Hub, which opened in 2018. In addition to creating a quality community space, the Community Hub was designed and built to be climate adaptive and reduce emissions. The Hub features the use of light-coloured materials for the carpark and building, water infiltration in the carpark, passive solar design principles, and maximises cross flow ventilation. Additionally, Cross Laminated Timber was chosen for the main building material, being close to carbon neutral in manufacture. The building features geothermal heating and cooling, which is far more energy efficient than traditional HVAC systems. It also features high performance glazing, insulation, efficient lighting, and solar to ensure emissions are minimised.

As another example, when tree planting projects are undertaken, they are planned in a way to cluster sites together. This makes establishment and maintenance more efficient and reduces transport and fuel use. Other examples include the City Park project in Penrith’s CBD, with a key aim of reducing urban heat by creating greenspace. The Park will utilise recycled materials such as brick from an on-site building, reducing the need for new materials, reducing the carbon footprint.

Council’s Buildings Policy for new and refurbished building assets includes objectives around cooling the city, resource efficiency, circular economy, renewable energy, net zero emissions with the aim of improving environmental performance.

How have the anticipated impacts of climate change been considered?

Resilience to future climate conditions is a core component of delivering Council’s Cooling the City program. The organisation is constantly looking for opportunities to increase the resilience of the program and future proofing it.

Council has been a formal supporter of the Which Plant Where project, coordinated by Macquarie and Western Sydney Universities. The project seeks to determine the future resilience of a wide variety of tree species, and their susceptibility to heat and drought conditions. The results of this project are being incorporated into Council’s work, including the development of a recommended Tree List of highly resilient species suitable for the Penrith area, enabling appropriate species selection for current and future tree planting initiatives. This Tree List will also be incorporated into Council’s Development Control Plan to ensure development across the Penrith area includes considered planting of appropriate trees for the Penrith climate.

Council is an active supporter of a project to pilot different approaches to passive irrigation of street trees. The project, which is currently in the planning stages, will monitor tree growth rates and success rates of different approaches and how they compare to each other. These results will be used to improve planting initiatives and ensure we maximise resilience to predicted future climate conditions.

Another key action has been a reinvestment in Council’s nursery, to maximise its capacity to support future tree planting projects. By doing so, we have increased our capacity to collect locally endemic seed stock, and grow plants adjusted to our local climate.

What processes does the initiative include for it to be considerate in its use of soils and other natural resources?

Council’s Cooling the City program seeks to work efficiently and in sync with the natural environment, in order to maximise cooling outcomes and the long-term success and growth of green infrastructure installed.

When planning tree planting initiatives, key consideration is given to how to work with and improve existing soil conditions. In suitable situations, such as a mass planting within a park or reserve, heavy mulch beds are laid down in advance of tree planting. This helps to suppress the existing grass, but more importantly improves the soil health and biodiversity in the lead up to planting. In the instances where pre-mulching of a site is not feasible, such as nature strip planting, mulching takes place after the trees have been planted, helping to trap and retain soil moisture, leading to long term health outcomes for the planted trees. Additionally, at an even earlier stage, careful consideration is given to species selection, ensuring that all tree planting initiatives utilise species suited to our local conditions, particularly our soils and climate, maximising the chances of success and reducing the need for artificial measures to keep trees healthy.

Care is also given to how water is managed as part of Council’s Cooling the City initiatives. The Jordan Springs Community Hub features Water Sensitive Urban Design features in the carpark, water efficient fittings, as well as a 16,000L water tank. Combined these were calculated to achieve a 22% reduction in stormwater leaving the site and a 25% reduction in overall potable water usage.