Murray–Darling Basin
18.18 Other groundwater decreases

Supporting information

The volumetric value for the line item for the 2011–12 year was 24,271 ML. The line item represents the reduction of supplementary entitlements during the 2011–12 year in New South Wales as stipulated in water sharing plans (see the following table). New South Wales supplementary access licence volumes are included in line item 2.5 Other groundwater assets as groundwater assets. These licence volumes are set to decrease each year until they disappear completely to bring all groundwater entitlements to a level of extraction that is sustainable.

 

Other groundwater decreases in the Murray-Darling Basin region in the 2011–12 year
Groundwater resource plan area

Groundwater sustainable diversion limit area

State

Volume (ML) for the 2011–12 year 

Code

Name

GW15 Gwydir Alluvium GS24 Lower Gwydir Alluvium NSW 1,992
GW14 Namoi Alluvium GS29 Lower Namoi Alluvium NSW 2,087
GS47 Upper Namoi Alluvium NSW 4,022
GW12 Macquarie–Castlereagh Alluvium GS26 Lower Macquarie Alluvium NSW 240
Sub-total Northern Basin 8,341
GW10 Lachlan Alluvium GS25 Lower Lachlan Alluvium NSW 2,124
GW9 Murrumbidgee Alluvium GS28 Lower Murrumbidgee Alluvium (deep; Calivil formation and Renmark Group) NSW 4,120
GW8 Murray Alluvium GS27 Lower Murray Alluvium (Deep: Renmark Group and Calivil formation) NSW 9,686
Sub-total Southern Basin 15,930
Total for the region 24,271


Quantification approach

Data source

Data was sourced from jurisdictional groundwater sharing plans.

Provided by

Bureau of Meteorology (the Bureau).

Method

Values were extracted from jurisdictional groundwater sharing plans.

Assumptions, limitations, caveats and approximations

It has been assumed that groundwater basic right is included in the permissible consumptive volume provided in relevant water sharing plan if no information is available to decide otherwise.

Uncertainty information

The uncertainty estimate was not quantified.

Comparative year

Availability of updated information resulted in the restatement of the 2010–11 year volume. Updated information was available for supplementary entitlement volumes for Lower Gwydir, Lower Macquarie and Lower Lachlan alluviums.  As a result, asset volume for these three alluviums has been reduced by 204 ML for the 2010–11 year. This volume is included in this line item to reflect the asset change.

 The respective volumes associated with the change are detailed in the following table.


Restatement of comparative year information made for the line item 18.18 Other groundwater decreases
Segment 2012 Account volume for the 2010–11 year (ML) 2011 Account volume for the 2010–11 year (ML) Difference due to updated information(ML)
Northern Basin

8,575

8,380

195

Southern Basin

6,254

6,245

9

Whole region

14,829

14,625

204