Perth
14.1 Adjustment and forfeiture of groundwater allocation

Supporting information

This line item refers to total forfeiture of groundwater allocations for all groundwater supply in the Perth region not related to urban water systems or irrigation schemes.

The volume recognised in the water accounting statements (18,134 ML) represents the total volume of terminated groundwater licences during the 2011–12 year.

Quantification approach

Data source

Water Resource Licensing database.

Provided by

Department of Water.

Method

The portion of groundwater allocation that has not been extracted at the end of the 2011–12 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 extraction is estimated to be the full allocation (see line item 18.11), this component of the forfeiture is assumed to be zero.

Entitlements that are terminated during the 2011–12 year are also considered to be forfeitures.

Assumptions, limitations, caveats and approximations

Given that the extraction data are estimated, the forfeiture is subject to the same assumptions and limitations of the extraction data (refer to line item 18.11).

Uncertainty information

The uncertainty estimate was not quantified.