A key component of Boroondara’s environment strategy involves the catchment, cleansing and deployment of rain water, through the following three projects.
Water tank
One of Australia’s largest underground water tanks sits beneath a popular local reserve in the City of Boroondara. The five million litre detention tank was constructed under Jacka Reserve in the suburb of North Balwyn, to prevent flash flooding of several houses that sit in a natural gully nearby.
Council will use the stormwater retained in the tank to nourish adjacent playing fields, saving about $40,000 a year in irrigation costs.
The $1.2 million project involved excavating an area equivalent to five basketball courts, to a depth of about four metres. The large rectangular dig was lined with heavy plastic and packed with 43,000 Australian made recycled plastic crates to stabilise the water mass it would contain.
Drainage pipes were connected to the tank before it was covered with a top layer of plastic, soil and grasses.
Rain gardens
Rain gardens are a key component of the City of Boroondara’s Water Strategy, Stormwater Environmental Management Plan and overall Environment Policy.
The City of Boroondara has installed several stormwater biofilters around the municipality. The beds of sandy loam soil planted with native grasses cleanse rainwater of chemicals and heavy metals from road runoff, before releasing it into the drainage system or channelling it for irrigation.
The first City of Boroondara rain garden, built in Marwal Avenue in the suburb of North Balwyn, received a Water Sensitive Urban Design Innovation Award and an Australian Institute of Landscape Architects Award in 2007. Since then, another seven rain gardens have been established at various locations around the municipality.
Wetlands
The City of Boroondara has allocated $500,000 for the design and landscaping of a wetland in the suburb of Glen Iris.
The wetland, on the 1.7 hectare site of a former bowls club, will improve the quality of stormwater entering Gardiners Creek.
An underground water storage tank will also be installed to allow the treated water to be collected for use on many surrounding sports grounds. This will reduce the need to transport recycled water from outside the municipality.
A second wetland, the Koonung Creek wetland in the suburb of North Balwyn, will be upgraded and improved to make it a permanent landscaped water feature that will also filter stormwater runoff.
Melbourne Water and property group, Stockland, are also contributing to this $1.79 million project.
