Ord
5.2 Surface water allocation remaining – urban water system

Supporting information

The volume recognised in the water accounting statements (670 ML) represents the volume of surface water allocation remaining for urban water supply licence entitlements in the Ord region at the end of the 2011–12 year.

The urban water supply licences relate to the following surface water resources:

  • Moochalabra Dam for Wyndham town supply
  • Ord River channel for water supply to Lake Argyle Village.

Quantification approach

Data source

Water Resource Licensing database.

Provided by

Department of Water.

Method

The water supply licences for Wyndham and Lake Argyle Village have a water management year that ends on 31 March. Therefore, the allocation remaining at the end of the 2011–12 year for the Ord region is the unused component of the annual allocation for these two urban licences.

The allocation remaining at 30 June 2012 was calculated as shown in the following table.

 

Volume of surface water allocation remaining for the urban water system at the start and end of the 2011–12 year

 

Account

Volume (ML)

 

Opening balance (at 30 June 2011)

735

add

21.2 Surface water allocation announcement (on 1 April 2012)

775

less

17.12 Surface water allocation diversion (up to 30 June 2012)

422

less

13.2 Adjustment and forfeiture of surface water allocation (on 30 March 2012)

418

 

Closing balance (at 30 June 2012)

670


Assumptions, limitations, caveats and approximations

Nil.

Uncertainty information

The uncertainty estimate was not quantified.

Comparative year

An error was made in the 2011 Account when calculating the total allocation remaining for urban surface water entitlements in the Ord region. The allocation remaining for the urban licence related to water supply to Lake Argyle Village was not included in the published volume. This error has been corrected in the 2012 Account. Consequently, the comparative year value was restated in the water accounting statements from 670 ML (as published in the 2011 Account) to 735 ML.