Murray–Darling Basin
17.17 Decrease of inter-region surface water claim on water

Supporting information

The line item applies only to the Southern Basin of the Murray–Darling Basin (MDB) region. The volumetric value for the line item for the 2011–12 year was 625,000 ML. The value represents decreases to the required annual release (RAR) by Snowy Hydro Limited (Snowy Hydro). More details about RAR are available in Line item 1.5 Inter-region claim on water. Decreases to the RAR include:

  • relaxation volume reduction (due to irrigators entitlements reaching full allocations and fullness of downstream storages
  • the volume reserved as directed by the New South Wales Office of Water under clause 13.2 of Snowy Water Licence to facilitate a potential inter-valley transfer  
  • the allocated volume for the drought account.

The following table provides information on the decrease of claims against Snowy Hydro from 01 July 2011–30 June 2012 and related to the Snowy Water Year of 01 May 2012–30 April 2013.

Decrease of claims against Snowy Hydro for the 2011–12 year
Description

 Volume (ML) for the 2011–12 year 

Tumut River (ML)

Murray River (ML)

Total (ML)

Repayment of water deals  0 0 0
Reduction in RAR for Snowy River deals (Mowamba) 0 0 0
Snowy Water Licence–reduction agreed between parties for the 2011–12 year 0 0 0
Relaxation volume reduction (due to irrigators entitlements reaching full allocations and fullness of downstream storages)

226,000

262,000

488,000
Reserved as directed by the New South Wales Office of Water under clause 13.2 of Snowy Water Licence to facilitate a potential inter-valley transfer

78,000

0

78,000
Allocated for the drought account

0

59,000

59,000
Decrease of claims against Snowy Hydro 304,000 321,000 625,000

Events that increase the claims against Snowy Hydro are shown under line item 9.15 Increase of inter-region claim on water.

Quantification approach

Data source

New South Wales Office of Water's water accounting section; and Snowy Hydro: Snowy Hydro Limited Water Operations Report.

Provided by

Bureau of Meteorology (the Bureau), NSW Office of Water and Snowy Hydro.

Method

  • Snowy Hydro required annual release at the beginning of the Snowy Water Year (1 May) is based on the calculations in the Snowy Water Licence.
  • Quantification method was not available for the water audit monitoring data received for this line item.

Assumptions, limitations, caveats and approximations

Snowy Hydro Claim: numbers were estimated at the commencement of the water year, and subject to revision and confirmation at the end of the year.

Uncertainty information

The uncertainty estimate was not quantified.

Comparative year

This line item corresponds to line item 17.17 'Decrease of inter-region claim on water' reported in the 2011 Account.