Sydney
9.9 Discharge from urban water system
Supporting Information
The volume of treated water from wastewater treatment plants and water recycling plants discharged to surface water during the 2010–11 year is 64,591 ML made up of flows that reached the sea (58,402 ML), and flows that reached downstream storages (6,189). Details of discharge volumes are provided in the following tables.
Sydney Water Corporation released 15,989 ML of recycled water from St Marys Water Recycling Plant to Boundary Creek (a tributary of the Nepean River). In the future, such releases are intended to replace outflows released for environmental purposes from Lake Burragorang (Warragamba Dam) to the river. The date for these releases is yet to be determined.
Description |
Plant |
Discharging to watercourse |
Volume discharged during 2010–11 (ML) |
Sydney Water Corporation – treated wastewater from water recycling plants
|
Castle Hill |
Cattai Creek |
2,991 |
Glenfield |
Georges River |
156 |
|
Liverpool |
Georges River |
1,434 |
|
Penrith |
Boundary Creek |
1,526 |
|
Picton |
Stonequarry Creek |
220 |
|
Quakers Hill |
Breakfast Creek |
6,946 |
|
Richmond |
Rickabys Creek |
501 |
|
Rouse Hill |
Second Ponds Creek |
3,887 |
|
St Marys |
South Creek |
3,662 |
|
St Marys |
Boundary Creek |
15,989 |
|
West Camden |
Matahil Creek |
1,805 |
|
Sydney Water Corporation – treated wastewater from wastewater treatment plants
|
Brooklyn |
Hawkesbury River |
94 |
Fairfield |
Orphan School Creek |
740 |
|
Hornsby Heights |
Calna Creek |
2,250 |
|
North Richmond |
Redbank Creek |
317 |
|
Riverstone |
Eastern Creek |
561 |
|
Wallacia |
Warragamba River |
227 |
|
West Hornsby |
Waitara Creek |
4,840 |
|
Winmalee |
Nepean River |
7,339 |
|
Shoalhaven City Council – treated wastewater from wastewater treatment plant
|
Berry |
Broughton Creek |
200 |
Bomaderry |
Abernathy's Creek |
844 |
|
Nowra |
Shoalhaven River |
1,873 |
|
Total |
58,402 |
The volumes shown in the previous table reached the sea. They did not become inflows to downstream storages.
Treated water released from wastewater treatment plants to streams reaching downstream storages are detailed in the following table. The volume reported below has been deducted from 9.4 Rainfall runoff.
Details of discharge volumes to downstream storages are also available in line item 19.5.
Operator |
Wastewater treatment plant |
Discharging to watercourse |
Reservoir receiving the discharge |
Volume discharged during 2010–11 (ML) |
Comments |
Goulburn Mulwaree Council |
Goulburn and Marulan |
No |
No |
0 |
The plants received 2,517 ML Treated water was used for irrigation |
Lithgow City Council |
Lithgow |
A tributary of the Coxs River |
Lake Lyell |
2,036 |
Metered inflows to the plants |
Wallerawang |
Coxs River |
Lake Wallace |
177 |
||
Palerang Council |
Braidwood |
A tributary of the Shoalhaven River |
Lake Yarrunga (Tallowa Dam) |
87 |
Estimated volume from metered inflow to the plant |
Wingecarribee Shire Council |
Berrima |
Olbury Creek |
Lake Burragorang (Warragamba Dam) |
101 |
Recorded from outflow meters |
Bowral |
Wingecarribee River |
1,594 |
|||
Braemar |
Iron Mines Creek |
1,013 |
|||
Bundanoon |
Reedy Creek |
283 |
|||
Moss Vale |
Whites Creek |
Medway |
898 |
||
Total |
6,189 |
|
Quantification Approach
Shoalhaven City Council
Data Source
Provided by
Method
Outflows from wastewater treatment plants were measured as follows:
- Berry Wastewater Treatment Plant: Vega-type ultrasonic flow meter
- Bomaderry and Nowra wastewater treatment plants: a Parshall flume with a venturi flow meter at each site.
Assumptions, Limitations, Caveats and Approximations
Uncertainty Information
The volume is based on measured data. Estimated uncertainty based on meter accuracy is +/– 5%.
Sydney Water Corporation
Data Source
Provided by
Method
Total metered volume of treated wastewater discharge to surface water from SWC's wastewater treatment plants and water recycling plants is provided. Water from St Marys Recycling plant was measured using SWC's Water Efficiency Report 2010–2011.
The flow of wastewater and recycled water from plants was measured using flow meters. These measured data are continually monitored and recorded using the Integrated Instrumentation Control Automation and Telemetry System (IICATS). The data are stored within a complex data management system. Adjustments are made to the data (if necessary) to correct any interruptions, errors and so on. Data have been extracted for 2010–11 from the data management system.
Assumptions, Limitations, Caveats and Approximations
The main difference between treated wastewater and recycled water produced by SWC is quality, and quality is determined by the level of treatment. Recycled water is produced by treating water generated from sewage, greywater or stormwater systems to achieve high quality as required. Information on SWC's wastewater treatment levels in producing recycled water is available on their website.
Uncertainty Information
The volume is based on measured data. Estimated uncertainty based on meter accuracy is +/– 2%.
Comparative year
The following table compares the value for the 2009–10 year reported in this account with the corresponding value reported in the 2010 Account.
2011 Account line item |
2010 Account line item |
Value reported in the 2010 Account (ML) |
Value reported in the 2011 Account (ML) |
Additional information |
9.9 Discharge from urban water system |
13.7.1 Discharge of urban wastewater to connected surface water |
54,576 |
56,556 |
Restatement: these two line items have been merged in the 2011 Account |
13.7.2 Urban recycled water discharge to connected surface water |
1,980 |