5.3 Surface water allocation remaining – irrigation scheme

Supporting information

This line item volume (6,510 ML) represents the volume of surface water allocation remaining for irrigation supply licence entitlements in the Perth region at the end of the 2012–13 year.

The irrigation scheme licences relate to the Harvey and Waroona irrigation districts within the Harvey Water Irrigation Area.

Quantification approach

Data source

Department of Water, Water Resource Licensing database; Harvey Water, Supervisory Control and Data Acquisition system.

Provided by

Department of Water; Harvey Water.


Prior to the 2012–13 year the licenced water management year for surface water supply to the Harvey Water Irrigation Area has been 1 July–30 June. Harvey Water is in the process of changing the water management year to 1 October–30 September to better reflect the irrigation season.

To make this change in licence water year, the current licence period for Harvey Water is 1 July 2012–30 September 2013. As a consequence, no forfeitures occurred during the 2012–13 year. The allocation remaining at 30 June 2013 is the volume remaining on the current 15-month licence, as shown in the following table.

Volume of surface water allocation remaining for the irrigation scheme at the start and end of the 2012–13 year



Volume (ML)


Opening balance (at 1 July 2012)



21.3 Surface water allocation announcements



17.13 Entitled diversion of allocated surface water



13.3 Adjustment and forfeiture of surface water allocation



Closing balance (at 30 June 2013)



Assumptions, limitations, caveats and approximations


Uncertainty information

The uncertainty estimate was not quantified.