Stormwater Harvesting at Melbourne and Olympic Parks 2025 Update
Stormwater Harvesting Management
The long-awaited rain finally descended on Melbourne after a scorching weekend. It’s the second week of the new year, with the aftertaste of the festive season lingering and a gradual transition from holiday mode to mundane reality. Offices are half-empty, and phones are uncharacteristically quiet. It’s a good time to catch up on those "not-so-critical" tasks that were put on the backburner during the pre-Christmas rush. Today also marks the first day of the opening week of the Australian Open 2025 at Melbourne Park.
Last year’s tournament broke all previous attendance records, with 1,020,763 fans passing through the gates during the main draw and an additional 89,894 spectators attending during the opening week. This brought the three-week total to an impressive 1,110,657 attendees. In preparation for (hopefully) even larger crowds at AO 2025, our humble contribution has been ensuring that the stormwater harvesting facility at Melbourne Park is "all systems go" and ready to supply recycled water to the event venues’ busy bathrooms.
Stormwater harvesting at Melbourne and Olympic Parks is a cornerstone of sustainable water management, ensuring efficient use of resources during high-profile events like the Australian Open. The facility incorporates advanced infrastructure, including underground tanks, pump stations, gross pollutant traps, and a state-of-the-art filtration system with granular activated carbon (GAC) and UV disinfection. This system not only ensures stormwater quality but also provides a reliable supply of recycled water for high-demand applications, such as flushing toilets at event venues. Comprehensive maintenance, sediment removal, and water quality management efforts have proven effective, preventing pollution from entering local waterways like the Yarra River while delivering environmentally responsible solutions for water reuse.
Water Quality
We began preparations in late July 2024 with a thorough inspection and cleaning of the external infrastructure, including underground tanks, pump stations, diversion pits, and gross pollutant traps. A total of 32 tons of sediment was removed during the cleanout—32 tons of pollution prevented from entering the Yarra.
The UV disinfection unit underwent its first major service in August 2024 (two years after its installation), which included both hardware and software upgrades. Watching the unit being fully dismantled and reassembled by the manufacturer’s engineers was quite an experience.
The formidable challenge of replacing the granular activated carbon (GAC) media in the filtration plant, located in an underground bunker, required careful planning and coordination.
Site work began in the third week of November, with the GAC filters tested, backwashed, and the treatment plant commissioned on December 11, 2024. Subsequently, water quality samples were taken from both the raw water and clear water tanks and sent to the laboratory on December 13. Following the receipt of the laboratory analysis report, the results were reviewed, and the recycled water was confirmed to be compliant with relevant Australian standards, regulations, and site-specific LRV targets developed through risk assessment.
It was also noted that the recent replacement of GAC media in the treatment filters significantly improved the treated water’s turbidity. This improvement allowed the UV system to apply a higher dose due to enhanced transmissivity, as reflected in the water quality test results.
| Parameter | Location of Sampling (13 Dec 2024) | |
|---|---|---|
| Raw Water Tank | Clear Water Tanks | |
| E.Coli (Quantitative) CFU/100ml | 11 | <1.0 |
| Nitrogen, Total as N (Calculated as TKN + NOX) in mg/l | 1.1 | |
| Phosphorus – Total as P in mg/l | 0.11 | |
| Turbidity in NTU | <1.0 | |
| Iron in mg/l | 0.14 | |
| pH | 7.7 | |
| Colour True (456nm) | 38 | 15 |
| Total Dissolved Solids in mg/l | 550 | |
| Conductivity in uS/cm | 460 | |
| Hardness mg equivalent CaCO3/L | 150 | |
The confirmation of water quality compliance was delivered to Melbourne and Olympic Parks management on December 18, just in time for the festive season break.
It was a mad rush, but we’re glad we got it done—ensuring the toilets at Melbourne Park venues will be flushed with recycled water during Australian Open 2025.
Stormwater Reuse and Recycling
The stormwater reuse and recycling initiatives at Melbourne and Olympic Parks demonstrate a commitment to sustainability and efficient water resource management. By harvesting, treating, and repurposing stormwater, the facility reduces reliance on potable water while addressing environmental concerns such as pollution and resource depletion. These efforts highlight the importance of integrating innovative technologies, rigorous maintenance, and compliance with water quality standards to achieve sustainable outcomes. As Melbourne Park gears up for another record-breaking Australian Open, its stormwater recycling system exemplifies how environmentally conscious practices can support large-scale events while protecting local ecosystems and ensuring long-term water security.