13.2 Adjustment and forfeiture of surface water allocation - urban water system

Supporting Information

The volume recognised in the water accounting statements (333 ML) represents the allocation forfeited for urban surface water entitlements in the Ord region during the 2010–11 year.

This refers to the licences to supply surface water to Wyndham and to Lake Argyle Village.

Quantification Approach

Data Source

Department of Water: Water Resource Licensing (WRL) database and Annual Reports/Meter Card readings from licensees.

Provided by

Department of Water.


Any unused allocation cannot be carried over to a subsequent licence year. For each licensee, the portion of an entitlement that has not been abstracted by end of its reporting period is forfeited.

That is, the portion of surface water allocation that has not been abstracted at the end of the 2010–11 year is forfeited. The forfeiture is calculated as the total annual allocation for each licence minus total allocation diversion. However, given that the volume of abstraction is estimated to be the full allocation (refer to line item 17.12), this component of the forfeiture is assumed to be zero.

Entitlements that are terminated during the 2010–11 year are also considered to be forfeitures.

Assumptions, Limitations, Caveats and Approximations

Forfeiture is calculated based on available abstraction data. Where the abstraction data are estimated, the forfeiture is subject to the same assumptions and limitations of the abstraction data. Refer to Line item 17.12 Surface water allocation diversion – urban system.

Uncertainty Information

The uncertainty estimate was not quantified.

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.

Comparative information from the 2010 Account for line item 13.2

2011 Account line item

2010 Account line item

Value reported in the 2010 Account (ML)

Value reported in the 2011 Account (ML)

Additional information

13.2 Adjustment and forfeiture of surface water allocation – urban water system Adjustment and forfeiture of allocation on regulated flows – urban holder



Volume restated due to subsequent availability of actual meter readings

This item has been restated because the Bureau of Meteorology reclassified the Lake Argyle Village licence (SWL166420) to urban supply. Also, availability of meter readings improved the accuracy of the volume presented.