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Everything that flows from the catchment into Port Phillip Bay affects its health. When it rains, water runs off our streets, gardens, and farms, carrying soil, rubbish, and chemicals into the Bay. By reducing these pollutants, we can help keep the Bay cleaner and healthier for everyone.
Protecting the Bay means looking at the whole system. Stormwater from the catchment and treated water from the Western Treatment Plant reach the Bay in different ways, but both influence its long-term health. That’s why our work spans everything from wetlands and waterway restoration to major treatment plant upgrades.
Recent water quality monitoring results from EPA Victoria show significant progress near the Western Treatment Plant: ammonia levels have fallen substantially over the last 30 years. Upgrades at the plant made a big difference, but it’s a collective effort; Melbourne Water has been working with its partners to improve waterway and catchment health across the whole region for decades. By building wetlands, improving how we treat stormwater, and running cleanup programs, we’re reducing pollution before it reaches the Bay.
Our Healthy Waterways Strategy, launched in 2018, guides this work. Good water quality matters not just for wildlife but also for people who swim, fish, and relax by the water. The Strategy sets clear targets to reduce contaminants such as sediments, nutrients, bacteria, and industrial chemicals. When our rivers and creeks are cleaner, Port Phillip Bay is healthier too.
Since the Strategy began, we’ve planted more than 3,190 hectares of new streamside habitat along important waterways. These plants act as natural filters, slowing rainwater and trapping pollution before it reaches our rivers. In just the past year, 643 more hectares were planted across the region, with a recent focus in the Maribyrnong and Westernport areas to accelerate progress against targets in these areas. All the major river catchments are on track to hit their goals for improved water quality from farm runoff. This success is thanks to working closely with local landowners and farmers.
Across Melbourne, we run a network of stormwater wetlands to capture run-off and pollutants, especially excess nutrients, before they reach Port Phillip Bay and Western Port. Last year alone, these wetlands removed 479 tonnes of nitrogen from the water, beating our annual target by a solid margin. This shows that our investments are making a real difference for the Bay.
But as Melbourne grows, managing stormwater is becoming tougher. More people mean more roads and concrete, which leads to more polluted runoff. Plus, climate change is bringing more intense storms heavier rain, with longer dry spells in between, making stormwater runoff even more complex. Some of our targets are ambitious and becoming harder to meet, but that’s why teamwork matters more than ever. We’re finding new solutions with councils, developers, and local communities.
Dealing with sewage is also getting trickier. While things have improved near the Western Treatment Plant, a growing population brings new challenges. We need flexible solutions that can keep up as Melbourne and our climate continue to change.
Protecting Port Phillip Bay is a long-term project, and the improvements near the Western Treatment Plant are just the beginning. By investing, partnering, and using the best science, we’re making stormwater cleaner. Together, we can keep the Bay healthy today, tomorrow and for generations to come.
