Murray–Darling Basin
9.15 Increase 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 2012–13 year was 1,748,700 ML. The line item includes the increases in required annual release (RAR) that Snowy Hydro Limited (Snowy Hydro) was required to deliver to the Tumut and the Murray River (1,739,397 ML), and a claim by Grampians Wimmera–Mallee Water in the Glenelg catchment (9,303 ML) for the 2012–13 year.

Claim for Snowy Hydro releases:

The values shown in the following table was the increase in the RAR for the period 1 July 2012–30 June 2013 and related to the Snowy water year of 1 May 2013–30 April 2014. It also includes the dry inflow sequence volume (DISV) adjustments made to the RAR during the year on a month-by-month basis and other RAR adjustments.

 

Required annual release for the 2012–13 year and Snowy water year 2013–14

Description

 Volume (ML) for the 2012–13 year

Tumut River (ML)

River Murray (ML)

Total (ML)

Fixed annual calculated yield for development

1,026,000

1,062,000

2,088,000

less Snowy water allocation

137,356

114,247

251,603

less DISV increase over year

0

97,000

97,000

plus Other RAR adjustment

0

0

0

equals Increase of claims against Snowy Hydro

888,644

850,753

1,739,397

Glenelg River

 

 

9,303

Total

 

 

1,748,700

   

Claim by Grampians WimmeraMallee Water on water in the Glenelg River

Under a Victorian bulk entitlement, Grampians Wimmera–Mallee Water is able to transfer water from the Glenelg River upstream of and including Rocklands Reservoir, and the first and second Wannon creeks upstream of and including the weirs to the Wimmera–Mallee supply system, located within the MDB region's boundaries.

The total of the water transferred-in during the 2012–13 year was 9,303 ML reported under line item 9.11 Delivery of water under inter-region agreement to surface water.

 

Quantification approach

Data source

(1) Snowy Hydro Limited: internal database; (2) New South Wales Office of Water's water accounting section: Snowy deals with New South Wales irrigators; and (3) Murray–Darling Basin Authority: water audit monitoring (WAM) data received from Victoria (14 February 2014) and stored in the HYDRO database.

Provided by

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

Method

  • The Snowy Hydro required annual release at the beginning of the Snowy water year (1 May) was based on the calculations in the Snowy Water licence.
  • The quantification method was not available for the WAM 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.

Inflows to Lake Hume for the Murray River are subject to a formula for calculating the respective New South Wales and Victorian shares, which is 50% between New South Wales and Victoria with some adjustments.

Uncertainty information

The uncertainty estimate was not quantified.