Sydney

   

Quantification approach  

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

Note a: Delta Electricity

 

Data source

Level monitoring at the reservoirs, a radio telemetry system and data spreadsheets.

 

Data provider

The following storage reservoirs are managed by Delta Electricity:

• Lake Lyell
• Lake Wallace
• Thomsons Creek Reservoir.

 

Method

• Lake Lyell: manual level readings converted to a volume using a rating table in a spreadsheet.
• Lake Wallace: telemetered level data from ultrasonic level sensors and radio telemetry system converted to a volume using a rating table in a spreadsheet.
• Thomsons Creek Reservoir: telemetered level data from pressure sensors and radio telemetry system converted to a volume using a rating table in a spreadsheet.

 

 

Uncertainty

The volume is based on measured data. Uncertainty value based on meter accuracy is
+/–5%.

The NSW Office of Water conducts an annual verification review on Delta Electricity’s water data.

 

Approximations, assumptions, caveats/limitations

Nil.

 

Note b: Goulburn Mulwaree Council

 

Data source

Level monitoring at the reservoirs and data spreadsheets.

 

Data provider

The following storage reservoirs are managed by Goulburn Mulwaree Council:

• Pejar Reservoir
• Sooley Reservoir.

 

 

Method

Telemetered level data converted to a volume using a rating table in a spreadsheet. For Pejar Reservoir, manual level readings were used for some of the 2009–10 season, because level sensors were non-functional due to low water levels.

 

Uncertainty

The volume is based on measured data. Uncertainty value based on meter accuracy and professional judgment is +/–5%.

 

Approximations, assumptions, caveats/limitations

Nil.

 

Note c: Lithgow City Council

 

 

Data source

Level monitoring at Farmers Creek No. 2 Reservoir and data spreadsheets.

 

Data provider

Farmers Creek No. 2 Reservoir managed by Lithgow City Council.

Method

Manual level readings converted to a volume using a rating table in a spreadsheet.

 

Uncertainty

The volume is based on measured data. Uncertainty value is ungraded.

 

Approximations, assumptions, caveats/limitations

Information on dead storage volume is not available.

 

Note d: Shoalhaven City Council

 

Data source

Level monitoring at the reservoirs with hydrometric sensors linking to council’s radio telemetry system.

 

Data provider

Following storage reservoirs managed by Shoalhaven City Council:

• Bamarang Reservoir
• Danjera Reservoir
• Flat Rock Creek Reservoir.

 

 

Method

Telemetered level data were converted to a volume using a rating table.

 

Uncertainty

The volume is based on measured data. Estimated uncertainty based on accuracy of level sensors and other level measuring devices, and rating tables is +/–5%.

 

Approximations, assumptions, caveats/limitations

Nil.

 

Note e: The Sydney Catchment Authority

 

Data source

Level monitoring at reservoirs—visual and hydrometric sensors, daily returns database and storage tables for reservoirs.

 

Data provider

The following storage reservoirs are managed by the Sydney Catchment Authority:

• Cataract Reservoir
• Cordeaux Reservoir
• Avon Reservoir
• Nepean Reservoir
• Woronora Reservoir
• Lake Burragorang (Warragamba Dam)
• Prospect Reservoir
• Wingecarribee Reservoir
• Fitzroy Falls Reservoir
• Lake Yarrunga (Tallowa Dam)
• Blue Mountains reservoirs
• • Medlow Reservoir
  • Greaves Creek Reservoir
  • Upper Cascade Reservoir
  • Middle Cascade Reservoir
  • Lower Cascade Reservoir.

Method

Water level by visual inspection of gauging boards and from hydrometric sensors. Level readings converted to volume using rating tables. Storage tables for reservoirs are developed from bathymetric surveys and other methods.

 

Uncertainty

The volume is based on measured data. Estimated uncertainty based on accuracy of sensors and other level measuring devices, and professional judgment on rating tables is +/–5%.

 

Approximations, assumptions, caveats/limitations

Nil.

 

Note f: Wingecarribee Shire Council

 

Data source

Level monitoring at the reservoirs with Vega-type hydrometric sensors linking to council’s radio telemetry system and data spreadsheets.

 

Data provider

Following storage reservoirs managed by Wingecarribee Shire Council:

• Bundanoon Reservoir
• Medway Reservoir.

 

Method

Water levels received from level sensors located in the reservoirs through council’s radio telemetry system are converted to a volume using rating tables. In addition, water levels obtained by operation officers are loaded into a spreadsheet where rating tables produce storage volume.

 

Uncertainty

The volume is based on measured data. Estimated uncertainty based on sensor accuracy, organisational practice and professional judgment on rating tables is +/–10%. The data are externally audited.

 

Approximations, assumptions, caveats/limitations

Information on dead storage volume is not available.