Sydney
19.7 Wastewater discharge outside of region

The total metered volume of treated wastewater discharged to the sea at wastewater treatment plants and water recycling plants managed by Shoalhaven City Council and Sydney Water Corporation during the 2011 Account is 428,215 ML (see the following table).

Total wastewater discharged out of region

Managing authority	Plant type	Plant	Discharge volume to sea (ML)
Shoalhaven City Council	Wastewater treatment	Shoalhaven Heads*	213
Sydney Water Corporation	Wastewater treatment	Bellambi	504
		Port Kembla	790
		Warriewood	6,815
		Shellharbour	7,031
		Cronulla	20,643
		Bondi	46,165
		North Head	143,815
		Malabar	185,499
	Water recycling plant	Gerroa	310
		Bombo	1,814
		Wollongong	14,616
Total			428,215

*Discharge occurs via sand dunes to the sea

Data managed and maintained in an internal data management system by Sydney Water Corporation's (SWC) Operations Division (Systems Assurance).

SWC.

The number represents the total volume of treated wastewater discharged to the sea, based on flow meter readings from wastewater treatment plants and water recycling plants managed by SWC.

The flow of wastewater from the 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 an internal data management system. Adjustments are made to the data (if necessary) to correct any interruptions, errors and so on. Data have been extracted for the 2010–11 year from the data management system.

Nil.

The volume is based on measured data. Estimated uncertainty based on meter accuracy is +/– 2%.

NSW Water Supply and Sewerage: 'Performance Monitoring' Report 2010–11. (Access through the 'Performance monitoring' webpage of the NSW Office of Water. The report will be included on the webpage from June 2012.)

Shoalhaven City Council.

Outflow volumes from Shoalhaven Heads Wastewater Treatment Plant were measured using an Elster meter and a Parshall flume with a venturi flow meter.

Treated wastewater was discharged to the sea via sand dunes, which act as natural sand-bed filters.

The volume is based on measured data. Estimated uncertainty based on meter accuracy is +/– 5%.

The following table compares the value at 30 June 2010 reported in this account with the corresponding value reported in the 2010 Account.

 

Comparative information from the 2010 Account for line item 19.7

2011 Account line item	2010 Account line item	Value reported in the 2010 Account (ML)	Value reported in the 2011 Account (ML)	Additional information
19.7 Wastewater discharge outside of region	20.4.2 Wastewater discharge out of region	395,186	395,186	Change in line item name