Find out how stormwater harvesting and re-use was implemented to help to keep the Fitzroy Gardens green and sustainable.
As well as being beautiful, Melbourne's iconic parks and gardens help to cool the city, clean the air and provide recreation space. Every year, approximately 120 million litres of water is needed to keep the trees, plants and turf in Fitzroy Gardens healthy. This is enough water to fill 50 Olympic-size swimming pools.
In recent years, water restrictions and the impacts of climate change, such as drought and heat waves, have made it difficult to supply enough water to keep the gardens healthy. Instead of relying on mains water, the City of Melbourne has constructed a new system in Fitzroy Gardens to collect water from the city's drains to use for irrigation.
The Fitzroy Gardens stormwater harvesting system is located beneath the ground next to this visitor centre. The system collects, cleans and stores water from stormwater drains. This water is then used for irrigating the plants in Fitzroy Gardens, reducing the use of drinking water by 59 per cent.
Construction of the system took approximately 18 months and was partially funded by the Commonwealth Government's Water for the Future initiative.
The Fitzroy Gardens stormwater harvesting system:
- Saves 69 million litres of drinking water per year, worth over $180,000
- Provides a reliable alternative water source for irrigation, securing the health and longevity of this heritage landscape
- Reduces pollutants such as nitrogen, phosphorus, sediment and heavy metals entering the Yarra River and Port Phillip Bay
- Increases the resilience of the landscape to the impacts of climate change, such as heat and drought
How the system works
The stormwater harvesting system sits underground near the visitor centre and collects water that runs off urban surfaces, such as roads and roofs. Located at a natural low-point in Fitzroy Gardens, stormwater is diverted from the existing underground drainage pipes that carry water collected from the surrounding urban areas into the Yarra River.
When the stormwater is diverted from the drains, it passes through a pollution trap and sedimentation chamber to remove litter, leaves, fine sands and oils.
The water then flows into the first storage tank, which can store up to 4 million litres. This water is pumped back to the surface into the biofiltration bed outside the visitor centre which naturally removes pollution as the water seeps down through the soil and roots.
The clean water is stored in a second underground tank until it is needed for irrigation. Before the water is pumped into the Fitzroy Gardens irrigation network it is passed over Ultra Violet light tubes to kill any remaining bacteria.
The creek in Fitzroy Gardens is a water feature that follows a natural drainage line from north to south through a number of ponds and fountains. As a result of water restrictions, the creek now only flows intermittently, the fountains are dry and stagnant water is often evident in the ponds.
The stream has been reconstructed and runs with recycled water from the stormwater harvesting system.