Sydney

The following tables provide a summary and breakdown of the allocation diversion of regulated flows by urban water utilities in the Sydney region.

The above table is based on supply records of the bulk supplier, SCA. However, the water receivers, in the form of the Shoalhaven City Council, Sydney Water Corporation and Wingecarribee Shire Council, record differences in received volumes. The differences have been attributed to limits in meter accuracy. In order to maintain consistency in calculations, the above table, as well as the accounting statements, show the volumes recorded by the bulk supplier.

The Fish River Water Supply Scheme delivered 520 ML to Lithgow City Council’s distribution system within the Sydney region. This volume was not diverted from surface water sources in the Sydney region. Therefore, it is not included in the above table, but instead included in Line item 19.5.6 Other lumped delivery of water transferred-in to water distribution system.

This line item comprises four different data-sets. The method for each data-set is shown below.

Note a: Goulburn Mulwaree Council

Data source

Data spreadsheets.

Data provider

Goulburn Mulwaree Council.

Method

Diversions to the water treatment plants (WTPs) were measured at the plants. At Goulburn WTP, inflow from the plant was measured using a flow meter.

Uncertainty

The volume is based on metered data. Estimated accuracy based on meter accuracy and professional judgment is +/–20%.

Approximations, assumptions, caveats/limitations

Nil.

Note b: Lithgow City Council

Data source

Data spreadsheets.

Data provider

Lithgow City Council.

Method

The flow diverted from Farmers Creek No. 2 Reservoir to Oakey Park WTP was measured by the height of the water over the weir in the channel. The outflow from the WTP was measured by an ABB Magflow meter.

Uncertainty

The volume is based on measured data. Estimated uncertainty based on meter accuracy is +/–2%. Meters are calibrated annually by ABB (meter supplier).

Approximations, assumptions, caveats/limitations

Nil.

Note c: The Sydney Catchment Authority

Data source

• Invoices.
• Daily Return System (DRS) database.
• Integrated Instrumentation Control Automation and Telemetry System (IICATS) meter readings.

Data provider

The Sydney Catchment Authority.

Method

Full-bore magnetic flow meters and ultrasonic flow meters were used to measure water diversions to urban utilities.

Uncertainty

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

Approximations, assumptions, caveats/limitations

There are minor differences in the supplied volumes recorded by the Sydney Catchment Authority and its recipients. In order to maintain consistency, the values provided by the Sydney Catchment Authority have been used for this line item.

Note d: Wingecarribee Shire Council

Data source

ABB Magflow meters based at raw-water pump stations, supervisory control and data acquisition (SCADA) system and Wingecarribee Shire Council data spreadsheets.

Data provider

Wingecarribee Shire Council.

Method

Volumes were derived from ABB Magflow meter data received through the SCADA system and transferred into spreadsheets.

Uncertainty

The volume is based on measured data. Estimated accuracy based on meter accuracy is +/–7%. External flow verification audits for the flow meters are conducted annually by Hydrometric Consulting Services.

Approximations, assumptions, caveats/limitations

The quantification method used in this note only applies to the council’s water diversions from Medway and Bundanoon storage reservoirs to their respective WTPs. Supplies to the council’s Wingecarribee WTP are made by the Sydney Catchment Authority.