Murray–Darling Basin
13.2 Adjustment and forfeiture of surface water allocation – urban water system

Supporting information

The volumetric value for the line item for the 2011–12 year was 285,743 ML. The line item includes adjustment and forfeiture of surface water allocation for urban water systems in the Murray–Darling Basin (MDB) region.


Adjustment and forfeiture of surface water allocation

The following two tables provide a summary and breakdown information on adjustment and forfeiture of surface water allocations for urban water systems within the region. 


Summary of adjustment and forfeiture of surface water allocation for urban water systems in the MDB region
Water Resource Plan (WRP) area

State/Territory

 Volume (ML) for the 2010–11 year 
 Code

Name

SW19 Warrego–Paroo–Nebine Qld 0
SW18 Condamine–Balonne Qld 0
SW17 Moonie Qld n/a
SW16 Qld Border Rivers Qld 0
SW15 NSW Border Rivers NSW 175
SW11 Barwon–Darling Watercourse NSW 0
SW12 NSW Intersecting Streams NSW n/a
SW14 Gwydir NSW 2,202
SW13 Namoi NSW 18,076
SW10 Macquarie–Castlereagh NSW 9,568
Sub-total Northern Basin 30,021
SW9 Lachlan NSW 10,474
SW8 Murrumbidgee NSW NSW 15,319
SW7 NSW Murray and Lower Darling NSW 26,711
SW3 Northern Victoria Vic. 55,627
SW2 Vic. Murray Vic. 6,469
SW4 Wimmera–Mallee Vic. 41,669
SW6 Eastern Mount Lofty Ranges SA n/a
SW5 SA Murray SA 71,243
SW1 ACT ACT 28,210
Sub-total Southern Basin 255,722
Total for the region 285,743

 

 

Details of adjustment and forfeiture of surface water allocation for urban water systems in the MDB region
Water resource plan area

Sustainable diversion limit (SDL) area

State/Territory

Entitlement class

 Volume (ML) for the 2011–12 year 

Code

Name

SW15 NSW Border Rivers  SS23 NSW Border Rivers  NSW Local water utility 175
SW14 Gwydir  SS22 Gwydir  NSW Local water utility 2,202
SW13 Namoi  SS21 Namoi  NSW Local water Utility 18,076
SW10 Macquarie–Castlereagh  SS20 Macquarie–Castlereagh  NSW Local water utility 9,528
NSW High security – town water supply 40
NSW Sub-total  9,568
SW9 Lachlan SS16 Lachlan NSW Local water utility 10,474
SW9 Murrumbidgee NSW SS15 Murrumbidgee NSW NSW Local water utility 15,319
High security – town water supply 0
Sub-total  15,319
SW7 NSW Murray and Lower Darling SS18 Lower Darling NSW Local water utility 9,029
SS14 NSW Murray NSW Local water utility 17,682
High security – town water supply 0
Sub-total  17,682
Sub-total New South Wales 82,525
SW3 Northern Victoria SS4 Ovens Vic. Urban–regulated 4,319
SS5 Broken Vic. Urban–regulated 1,041
SS6 Goulburn Vic. Urban–regulated 15,429
SS7 Campaspe Vic. Urban–regulated 35,482
SS8 Loddon Vic. Urban–regulated -644
SW2 Vic. Murray SS2 Vic Murray Vic. Urban–regulated 6,469
SW4 Wimmera–Mallee SS9 Wimmera–Mallee Vic. Urban–regulated 41,669
Sub-total Victoria 103,765
SW6 Eastern Mount Lofty Ranges SS13 Eastern Mount Lofty Ranges SA Urban

SW5 SA Murray SS11 SA Murray SA Class 2 – Other urban (country town) water supply

Class 6 – Metro-Adelaide water supply scheme

Combined classes urban 71,243
Sub-total  71,243
SS10 SA Non-prescribed areas SA Urban

SW6 Eastern Mount Lofty Ranges SS12 Marne Saunders SA Urban

Sub-total South Australia 71,243
SW1 ACT SS1 ACT ACT Urban–regulated  28,210
Total for the region 285,743

– = Data not available

 

Queensland

In Queensland, the resource operation plans (ROPs) distinguish between high and medium priority of supplemented water allocation. The water audit monitoring (WAM) data, which are the data source for the 2012 Account, only distinguish between supplemented and unsupplemented entitlements. Both urban and non-urban entitlements are included within supplemented entitlement class. Supplemented urban and supplemented non-urban volumes on allocations, diversions and other attributes were received together and it is not possible for these to be separated out for two purposes. Therefore, adjustment and forfeiture of surface water allocation for both urban and non-urban supplemented entitlements are included in line item 13.1 Adjustment and forfeiture of surface water allocation.     

New South Wales

New South Wales volumes reported in this line item contain the adjustment and forfeiture made under major and local water utility classes as well as the high security town water supply class.

Victoria

Victorian allocation adjustment and forfeiture are shown in the source valley, even though the water was taken in a different destination valley. Therefore all entitlements in the Goulburn SDL area have their allocation adjustments and forfeiture shown in that area, rather than the destination valleys of the Loddon or the Campaspe.

South Australia

In this line item for South Australia, adjustment and forfeiture volumes include the classes 2 and 6 as a combined class urban. 

Australian Capital Territory

In the Australian Capital Territory, no formal allocation announcement is made to extract water from storages. The allocation announcement for the year is assumed to be equal to the total entitlement volume. The difference between the allocation announcement and the allocation diversion is considered as forfeited.

Quantification approach

Data source

(1) New South Wales Office of Water: water accounting section; (2) Environment and Sustainable Development Directorate of the ACT Government: water resource information database; and (3) Murray–Darling Basin Authority: WAM data received from Australian Capital Territory (10 January 2013), Queensland (4 February 2013), South Australia (15 March 2013), and Victoria (21 March 2013), and stored in the HYDRO database.

Provided by

Bureau of Meteorology (the Bureau).

Method

  • In Queensland allocation remaining is generally not available in the supplemented systems for urban holders and therefore all allocation remaining at the end of the year is forfeited. This does not apply in the St George (Condamine–Balonne SDL area), Border Rivers and Macintyre Brook (Queensland Border Rivers SDL area) water supply schemes which are continuous share schemes. Allocation adjustment and forfeiture is calculated using WAM data on a water balance approach.
  • The New South Wales Office of Water supplied data are prepared on a water balance approach. The forfeitures and adjustments have been checked to ensure that the closing balance reconciles.
  • Victorian adjustment and forfeiture was calculated applying a water balance approach to WAM data.
  • In ACT and South Australia unused urban allocation is not available for carry-over into the next year. The allocation adjustment and forfeiture is calculated as the difference between the allocation announced and the allocation diverted. Despite this, provision has been made under the Murray–Darling Basin agreement to store and support delivery of South Australian's critical human water needs for the forthcoming year (as a share of the South Australian's entitlement to River Murray water).

 

Assumptions, limitations, caveats and approximations

Uncertainty reported by New South Wales Office of Water accounts for possible errors in the quantification of diversion and in the data handling processes.

Information provided in this line item may have been based on Cap valleys in the HYDRO database, which may not align perfectly with SDL areas.

Uncertainty information

WAM supplied data are either measured, modelled or estimated. Uncertainty for volumes provided for New South Wales was estimated to be +/– 10%. The uncertainty estimate was not quantified for all other adjustment and forfeiture volumes included in this line item.

Comparative year

Availability of updated information resulted in the restatement of the 2010–11 year volume. For the 2012 Account, Adjustment and forfeiture volume for SA Murray SDL area reported in the 2011 Account has been increased by 17,700 ML for the 2010–11 year due to updated information. The respective volumes associated with the change are detailed in the following table.


 

Restatement of comparative year information made for the line item 13.2 Adjustment and forfeiture of surface water allocation – urban water system
Segment 2012 Account volume for the 2010–11 year (ML) 2011 Account volume for the 2010–11 year (ML) Difference due to availability of updated information (ML)
Northern Basin 26,606 26,606 0
Southern Basin 262,492 244,792 17,700
Whole region 289,098 271,398 17,700