Water & Catchments
Sydney Olympic Park has a locally-integrated approach to water conservation based on stormwater harvesting, wastewater reprocessing and reducing water demand. A whole-of-catchment approach has been built into the design of the Park and links management of potable water, recycled water, rainwater, irrigation water, building design, landscape plantings and aquatic habitats.
Stormwater runoff from Sydney Olympic Park drains to the Parramatta River via Haslams Creek, Powells Creek, Boundary Creek, and the Park’s freshwater and estuarine wetlands. Pollution-control devices including gross pollutant traps (GPTs), continuous deflective separation units (CDS units) and water quality control ponds have been installed throughout the Park to capture locally-generated pollutants and protect local waterways.
However the Park is situated at the lower end of highly-urbanised catchments and significant quantities of rubbish are carried into Haslams Creek, Powells Creek and Boundary Creek from upstream. Such rubbish can smother the Park’s endangered saltmarshes, pollute its mangrove forests, and pose a risk to wildlife that ingest or become entangled in it. Sydney Olympic Park Authority has installed stormwater litter booms where these creeks enter the Park, and in 2009-10, intercepted and removed over 125 tonnes of rubbish carried into the Park from upstream.
Three on-site water quality control ponds collect stormwater runoff from the pavements, roads and rooftops of much of the Town Centre. These ponds are planted with aquatic plants and are designed to collect the ‘first flush’ of stormwater – they allow sediments to settle and nutrients such as nitrogen and phosphorus to be removed. The stormwater is then either re-used for irrigation or in production of recycled water, or overflows into local creeks and wetlands. The ponds also provide important habitat for the endangered Green and Golden Bell Frog, and breeding habitat for a variety of waterbird species.
Stormwater runoff from the 14-hectare P5 carpark and from much of the suburb of Newington is collected into irrigation storage ponds in Narawang Wetland. From here it is used to fill the 22 wildlife habitat ponds within the wetland, and for irrigation of parkland landscapes and the Wilson Park playing field.
The Park’s Water Reclamation and Management Scheme (WRAMS) commenced operation in 2000 and was Australia’s first large-scale urban water treatment scheme.
WRAMS recycles water from sewage and stormwater to supply irrigation, ornamental fountain and toilet flushing applications across Sydney Olympic Park and in the suburb of Newington. Office buildings, sporting and entertainment venues and Newington residences are all connected to this recycled water, which is supplied to customers through separate meters and at a lower cost than potable water supplied by Sydney Water.
WRAMS saves more than 850 million litres of potable water annually by avoiding its use for non-drinking purposes. In addition, the sewer-mining function of WRAMS treats approximately 550 million litres of sewage each year, which would otherwise be discharged to ocean outfalls.
Reducing Water Demand
Less than 5% of all water used at Sydney Olympic Park is potable water –it is typically only used where recycled water or harvested stormwater cannot be used – such as for drinking water, showers and handbasins, and by the sports venues to top up swimming pools and to provide the correct surface moisture for hockey playing fields.
Design and management practices which reduce water demand include:
- Widespread use of drought-tolerant native plants in landscape plantings across the Park. These plants are already adapted to the rainfall patterns of the area and have little need for irrigation once established.
- Irrigation of lawns and plantings is generally undertaken at night, when evaporation is low
- Use of permeable paving and porous gravel in much of the Town Centre, to provide rainwater infiltration for street trees and to reduce the volume of stormwater runoff generated from hard surfaces
- Sub-surface irrigation of the Wilson Park playing field, installed because it requires significantly less water than a surface irrigation system.