Perth

The volume recognised in the Statement of Water Assets and Water Liabilities represents the volume of groundwater allocation remaining for urban supply licence entitlements at the end of the reporting period (30 June 2010).

Data source

Western Australian Department of Water: Water Resource Licensing database.

Data provider

Western Australian Department of Water.

Method

For all but one of the 10 bore fields within the Perth region, the licensed water management year is from 1 July to 30 June. For these licences, any unused allocation at the end of the water management year is forfeited and, therefore, the allocation remaining at the end of the reporting period is zero.

The groundwater supply licence for the Gingin bore field has a water management year that ends on 30 September. Therefore, the allocation remaining at the end of the reporting period (30 June 2010) for the Perth region is the unused component of the annual allocation for the Gingin bore field.

The allocation remaining was calculated as shown in the table below.

Uncertainty

Ungraded.

Approximations, assumptions, caveats/limitations

Nil.