5.1 Surface water allocation remaining

Supporting Information

The volume recognised in the Statement of water assets and water liabilities represents the volume of surface water allocation remaining for entitlements holders for individual holders for stock and domestic, and other lumped holders.

As the remaining allocation at the end of the 2010–11 year is forfeited, the opening and closing balance is 0 ML. Reconciliation of this line item is shown in the following table.

Calculation of the surface water allocation remaining for the 2010–11 year
Line item
Volume (ML)


5.1 Opening balance (as at 1 July 2010)



21.1 Surface water allocation announcements



17.11 Surface water allocation diversion



13.1 Adjustment and forfeiture of surface water allocation



5.1 Closing balance (as at 30 June 2011)



Quantification Approach

Data Source

Draft Water Sharing Plan — Greater Metropolitan Unregulated River Water Sources; entitlement data recorded in databases and water management licences for Goulburn Mulwaree Council, Lithgow City Council, Shoalhaven City Council and Wingecarribee Shire Council.

Provided by

Bureau of Meteorology: calculated opening and closing balance; NSW Office of Water, Shoalhaven City Council, Goulburn Mulwaree Council, Palerang City Council and Sydney Water Corporation provided entitlement data.


Mapping entitlement values stated in the Draft Water Sharing Plan—Greater Metropolitan Unregulated River Water Sources, water management registers, and licence and trading statistics to the relevant categories of entitlements. Diversion data were obtained from the relevant authorities as shown in line item 17.11.

For each water management licence, the licensed water management year is from 1 July to 30 June. At the end of the water management year, any unused allocation is forfeited. Therefore, the allocation remaining on 30 June of the reporting year is zero, as shown in the previous reconciliation table.

Assumptions, Limitations, Caveats and Approximations


Uncertainty Information

NSW Office of Water – values associated with this line item were estimated. Estimated uncertainty is +/– 30% to 50% based on professional judgment and established practice within the NSW Office of Water.

Goulburn Mulwaree Council – the volume is based on metered data. Estimated accuracy based on meter accuracy and professional judgment is +/– 20%.

Sydney Water Corporation – the volume is based on measured data. Estimated accuracy based on meter accuracy is +/– 2%.

Comparative year

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 5.1

2011 Account line item

2010 Account line item

Value reported in the 2010 Account (ML)

Value reported in the 2011 Account (ML)

Additional information

5.1 Surface water allocation remaining 

Not applicable

Not applicable


Line item presentation: water rights associated with this line item were not recognised in the 2010 Account. In order to reconcile this line item and recognise the water rights, this volume has been included.