Moore Reserve wetland
Filtering pollutants before they reach the Georges River
What has been achieved
An artificial wetland was constructed in 2001 which uses natural processes to treat 95% of all stormwater run off from the 125-hectare catchment before it enters Oatley Bay.
The 14.2 hectare Moore Reserve is the second largest public space in Kogarah. It was created in the 1960's by infilling with mud dredged from Oatley Bay. At the time the existing natural waterway, Renown Creek, was destroyed and ultimately replaced by concrete pipes.
Between 1964 - 1977, the area was used as a rubbish tip with an estimated 375,000 tonnes of waste deposited at an average depth of five metres.
Kogarah Council has been committed to rehabilitating the reserve to address issues such as methane gas, groundwater pollution (leachate), and stormwater run off.
How it Works
The Moore Reserve Draft Master Plan (1997) identified stormwater pollution as a major contributor to poor water quality and increased levels of sediment in Oatley Bay.
The construction of the wetland is the first stage in Moore Reserve's ecological restoration.
The wetland and filtering system treats stormwater from surrounding residential, industrial and commercial areas to remove litter, nutrients, heavy metals and sediments.
There are four key steps in the process:
Step 1 - Pollutant trap
Stormwater enters two underground pollutant traps in the reserve (CDS unit). Litter, oil and sediment are removed from the stormwater before it flows to the wetland. An average 2 tonnes of rubbish is collected every month from the units and is taken to a waste disposal facility.
Step 2 - Settling sediment
Stormwater enters the wetland near an island that slows down the flow of the water. It is 2 metres deep here so that sediment with heavy metals attached can settle and remain undisturbed.
Step 3 - Nutrient take up
Water moves slowly through the wetland into a shallower section (0.5 metres) filled with reeds and sedges (macrophytes). These plants take up nutrients from the stormwater and use them for plant growth. This shallow zone has the most aquatic life and includes turtles, invertebrates, birds and frogs. What appears as 'shaving foam' among the plants is actually frog eggs.
Step 4 - Removing bacteria
The final deep section of the wetland allows sunlight and wind to continue to break down bacteria that remains in the water. Cleansed water then flows to an outlet pipe and into Oatley Bay.
Benefits of the Wetland
- Removes pollutants such as nutrients, sediments , heavy metals and litter
- Improves water quality in Oatley Bay
- Creates habitat for aquatic life and birds
- Improves the aesthetic and recreational value of Moore Reserve
- Provides educational opportunities for local schools and community groups
Funding and Future Plans
The $1.5 million rehabilitation program at Moore Reserve is funded by Kogarah Council and the NSW Government.
The wetland is the first step in rehabilitating Moore Reserve.
To assist and guide Council in the recovery of Moore Reserve a Voluntary Remediation Agreement (VRA) was developed the Department of Conservation and Climate Change. This agreement outlined the stages of the remediation program including additional and ongong monitoring and a Moore Reserve Management Plan.
Promising Results So far...
Analysis of stormwater water quality entering Oatley Bay at Moore Reserve show dramatic improvements since rehabilitation began:
- In 1996, water samples show high levels of heavy metals such as copper (5 micrograms per litre) and zinc (55 micrograms per litre)
- By 2003 copper measured just 2 micrograms per litre, while zinc was 11 micrograms per litre
Moore Reserve Wetland Renewal
Kogarah City Council is committed to improving stormwater quality and recognises the importance of Water Sensitive Urban Design (WSUD) projects to promote cleaner stormwater entering the Georges River and its bays.
The Moore Reserve Wetland was one of the first large scale WSUD projects undertaken by Council in order to treat catchment stormwater while developing a new aquatic habitat. Since then, the wetland has matured and currently supports large areas of native aquatic vegetation, numerous fish, frog, macroinvertebrate and water bird species, as well as eastern long-necked turtles.
Kogarah City Council is currently undertaking an assessment and management works program to revitalize the wetland environment and ensure continued growth of this high biodiversity area while improving water quality entering Oatley Bay. The project is funded by the Lower Georges River Sustainability Initiative (LGRSI) as part of the Riparian Regeneration Initiative. It has been assisted by the NSW Government with funding through the Environmental Trust. The program allows works to be undertaken to improve riparian habitats within the lower reaches of the Georges River.
High biodiversity is something that people do not usually consider possible in urbanised environments like Kogarah. Most people would be surprised to know that the area is home to such a wide range of native plants and animals. This is why habitat areas like Moore Reserve Wetland are so important. Moore Reserve Wetland is a refuge habitat for many of the native animals that live in urban areas and is an important link to other local habitats. Many frogs breed and live within the wetland and migrate into other bushland areas, wetlands and even into residential backyards.
You can help maintain our natural habitats by volunteering with Council's Community Environment Programmes such as Bushcare and Streamwatch. For more information, contact Council's Customer Service Centre on 9330 9400.