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National Water Account 2018

South East Queensland: Statement details

  • End of year storage volume increased to 79% full from 75% full last year, despite marginally below-average annual rainfall.
  • The increase in storage volume is mainly due to inflows from rainfall events in October and late February.

Diagram showing  rainfall, runoff, and storage volumes for the South East Queensland region for the 2017–18 year compared to the previous year.

For further information on the region's water accounting statements scroll down this page or click on the links below:

Water assets

Surface water assets

  • Surface water asset volumes in the South East Queensland region were 2,128,225 ML at 30 June 2018.

 

Figure S1 Total storage volume in the region at 30 June 2017 compared with the previous 8 years

Figure S1 Total storage volume in the region at 30 June 2018 compared with the previous 8 years

 

  • Five storages (Wivenhoe, Somerset, Hinze, North Pine and Wyaralong) provide more than 80% of the region's total surface water storage.
  • Storage volumes increased from 75% full at 30 June 2017 to 79% full at 30 June 2018.

 

Figure S2 Percentage-full volume on 30 June 2018 for each storage

Figure S2 Percentage-full volume on 30 June 2018 for each storage

 

  • By October 2017, storage volumes had decreased to 70% full; however, high rainfall in mid-October and February contributed to storages being 79% full by the end of the year.
  • Wivenhoe—the largest storage in the region—dropped below 70% full during the year for the first time since 2010.
  • More detailed information on the individual storages within the region is available on the Bureau of Meteorology's Water Storage website.

 

Water liabilities

  • Water liabilities in the South East Queensland region refer to the volume of allocation remaining on licence entitlements at the end of the 2017–18 year.

 

Table S1 Volume of surface water allocation remaining at 30 June 2018
Description Individual users (ML)Urban system (ML)
 Opening balance at 1 July 201700
addAllocation60,969484,117
lessAllocated diversion17,281320,949
lessAdjustment and forfeiture43,688163,168
 Closing balance at 30 June 201800

 

Table S2 Volume of groundwater allocation remaining at 30 June 2018
Description Individual users (ML)
 Opening balance at 1 July 20170
addAllocation11,115
lessAllocated diversion5,972
lessAdjustment and forfeiture5,143
 Closing balance at 30 June 20180

 

  • All water supply licences for the region have a water management year that ends on 30 June.
  • As there are no carry-over provisions for water supply licences in the South East Queensland region, the portion of water allocation that has not been abstracted at the end of a water year is forfeited and the allocation remaining at the end of the year is 0 ML.
  • A more detailed description of water allocations and associated water rights in the South East Queensland region is given in the Water access and use note.

 

Water asset increases

  • Total water asset increases for the year was 3,702,850 ML. 
  • The key item contributing to water asset increases for the region was runoff, which made up 68% of total water asset increases.
  • Runoff was approximately 30% below average due to the dry conditions for most months of the year.
  • Urban water system increases primarily represent claims:surface water and wastewater collected, which generally change little from year to year.

 

Water asset decreases

  • Total water asset decreases for the year was 2,985,930 ML.
  • The key item contributing to water asset decreases for the region was outflow, which made up 49% of the total water asset decreases.
  • Outflow was approximately 60% below average reflecting the relatively low rainfall for most months of the year.
  • Urban water system decreases primarily represents discharge: sea and supply system delivery: urban users.

 

Water flows

  • Total water inflows to the region was 3,539,682 ML, lower than the volume of water asset increases (3,702,850 ML). Total water inflows include allocated surface water diversions and groundwater extractions by the urban water system; total water asset increases include the annual allocation for surface water and groundwater for the urban water system.
  • Total water outflows from the region was 3,166,964 ML, higher than the volume of water asset decreases (2,985,930 ML). Total water outflows include the flows corresponding to the accrual transations–allocated diversions and allocated extractions. Total water asset decreases include the forfeiture of allocations. 
  • A detailed description on all the water flows associated with the surface water and groundwater stores, as well as the urban system, is provided in the Water stores note. 

 

Unaccounted-for difference

  • The unaccounted-for difference is the volume necessary to reconcile the opening water storage and closing water storage with the total water inflows and total water outflows reported in the water accounting statements.

 

Table S3 Calculation of unaccounted-for difference for the 2017–18 year
Description Volume (ML)
 Closing water storage balance at 30 June 20182,139,340
lessTotal inflows3,539,682
addTotal outflows3,166,964
lessOpening water storage balance at 1 July 20172,044,927
 Unaccounted-for difference(278,305)

 

  • The relatively high unaccounted-for difference value is primarily attributed to the fact that river losses are not quantified, as well as uncertainties associated with the runoff estimate (see Methods).