Brimbank, Australia

Photo by Emma Cross

The power of plants and natural ecosystems to deliver benefits

How is the initiative shaped by scientific evidence of the potential for plants and natural ecosystems to deliver benefits?

Australian bushfires in 2009 directly claimed the lives of 173 people in Melbourne, with an additional 374 people dying in the heatwave leading to the bushfire. Many of these people lived in the north and west of Melbourne and one reason attributed to this death rate is the lack of tree canopy cover.
Sunvale Community Park has an integrated blue/green infrastructure system that treats stormwater water from surrounding streets and an adjacent townhouse development. All the stormwater is directed to raingardens, treated and then stored underground in a 100,000-litre tank. This water is used for irrigation and to keep the park cool during heatwaves. Council can turn the irrigation before or during a heatwave to create a cool park.

This approach to designing parks that are green and cool forms part of a Council initiative called Oasis Parks where plants and water are integrated to create places of biodiversity and refuge for people and nature.

Council has also planted plants from warmer climates north of Melbourne such as Morton Bay Figs which are expected to grow well as the climate changes in Melbourne during this century. The tree canopy cover is expected at Sunvale to be at least 60% which exceeds Council’s Urban Forest Strategy that seeks a 30% canopy cover overall across Brimbank.

Plants are a vital component of the design of Sunvale as per the following breakdown:

• 101 advanced trees
• 9,000 smaller trees, palms, ferns, shrugs, groundcovers
• 725 raingarden plants

How has the city exploited the potential of plants and associated ecosystems to deliver more than one benefit?

As part of the community consultation, there was a strong desire for a Botanical Garden experience. The planting palette and design have sought to create this experience through a selection of indigenous, native and exotic plants. The following benefits will increasing develop overtime as the blue/green infrastructure evolves at Sunvale:

• Raingarden plants will filter and clean stormwater and provide habitat and food for urban birds and insects. Frogs are expected to be attracted to the raingardens over time. The vegetation in all raingardens is indigenous to the local area
• The expected 60-70% canopy cover will increase habitat and food supply for urban birds and insects while providing heatwave mitigation and supporting the physical and mental well-being of the local community through increased connection to nature
• Trees and plants have been chosen based on their water requirements. Some areas are not irrigated and in these areas native trees/shrubs have been selected
• A community orchard and herb garden provides ongoing urban harvesting for the local community
• Existing mature trees were retained to ensure no loss of existing ecosystem functions while a large eucalypt that was dying and considered dangerous has had its canopy removed but large limbs were kept to provide hollow nesting opportunities for birds and also perching opportunities for raptors.