Improving waterway health across Sydney

Putting more life in our waterways

The health of our waterways and wetlands is essential to the liveability of Sydney, and the investment approved by IPART (the Independent Pricing and Regulatory Tribunal) in the Waterway Health Improvement Program as part of our 2020–24 price review. As part of the price review process, we asked customers if they'd be willing to pay more for particular projects. For waterways health, customers said yes. So from 1 July 2021, all stormwater customers are contributing a modest 86 cents a year, included in their stormwater service charge, to fund this sweeping program. 

Keep up to date on progress
Each year, we’ll report on the progress of this project on our website and through information included with your bill. You can visit our prices for homes and businesses for your stormwater service charges. 

We're working to plant naturally vegetated stormwater treatment areas, also known as Water Sensitive Urban Design (WSUD) across Sydney. We hope to benefit communities by creating enjoyable spaces that also improve water quality.

By improving waterway health in the Georges, Cook and Parramatta River catchments, we're also creating new habitat for wildlife to thrive and revitalised spaces for the community to enjoy. Together with local councils, we're exploring locations where we can reduce the amount of rubbish and other pollutants in our waterways.

The result will be natural, planted vegetation areas that filter stormwater through physical and biological processes. Pipes divert water from rivers and creeks into a treatment area (known as a bio-retention system) where native vegetation filters the stormwater and allows sediment to fall.

Microorganisms growing on these plants absorb the pollutants in the water, and then another pipe diverts water back into the catchment.

We're making Sydney more liveable by improving its wetlands.

We're engaging with the community at the following sites:

  • Parkside Drive Reserve, Kogarah Bay – Georges River Catchment
    We're working with Georges River Council to improve the health of water entering Kogarah Bay and create new habitat for wildlife in the area.
  • Mackey Park, Marrickville – Cooks River catchment
    We're working with the Inner West Council to expand stormwater treatment areas in Mackey Park. This is aligned with the Cooks River Parklands Master Plan.
  • Mildura Reserve, Campsie – Cooks River catchment 
    We're working with City of Canterbury Bankstown to ensure cleaner water enters Cooks River. This will provide a beautiful and usable space for the community to enjoy.
  • Ruse Park, Bankstown – Cooks River catchment
    We're working to improve waterway health and improve pedestrian and cycle connections on behalf of the City of Canterbury Bankstown.
  • Milson Park, Wentworthville/Westmead – Parramatta River catchment
    We're working with the City of Parramatta to finalise the upgrade plan for Milson Park, which will revitalise a currently grassed open area. We consulted with the community about this project in late 2017.

Visit to keep track of these projects.


What are the expected impacts of the work?

Waterway health in these catchments will be improved. There may be opportunities to explore additional seating, picnic or nature play areas.

The works all support a balanced ecosystem and the stormwater treatment areas will look like natural, planted vegetation.

Some impacts are expected during construction, such as noise and vehicle movements. 

How will the stormwater treatment affect the presence of mosquitos and other insects?

Stormwater treatment areas create a balanced ecosystem. Most treatment areas are designed to dry after rain so insect presence will be low. It will also be balanced by the attraction of frogs and dragonflies to these spaces, limiting mosquitos.

In periods of heavy rain, we can manually drain the areas to reduce the presence of mosquitos.

What happens if the water in the treatment area becomes stagnant?

The water won't be stagnant as we use gravity pipes to maintain the flow of water across the treatment area and out to the catchment.

Treatment areas may sometimes be dry as the system is designed to drain after rain.

During periods of rainfall, the water may reach a shallow depth of 30 centimetres.

How many trees will we remove during this work?

These projects involve thousands of native plantings to create the new stormwater treatment area, which will greatly improve the overall environmental health of the ecosystem. 

We’ll only remove specific trees if it's really necessary. We always do a case by case assessment of what's needed and always avoid removing trees. If we do need to remove a tree, we'll always try to replace it.

How can we prevent weeds growing in the area?

As part of our planning process, we choose native plants to ensure our natural vegetation can thrive. Once the treatment area is planted, the community will need to avoid dumping garden waste or rubbish into the area, as this contaminates the water and can damage native plants and waterways.

When will the work happen?

We're likely to start construction over the next 2 years, but this depends on the outcome of consultation with the local council and the community.

Who will be responsible for the areas once they're built?

We'll be responsible for the ongoing maintenance of the stormwater treatment system. The reserve and open space next to the stormwater treatment area will continue to be maintained by the council.

How will rubbish and litter be captured?

Rubbish and litter will be captured in an underground tank which has a screen to capture any litter.

To learn more about improving waterway health in Sydney, call us on 13 20 92.