Murray–Darling Basin: Statement details
- Dry conditions contributed to very low runoff and storage inflows across the region.
- End of year storage volume dropped to 32% full, the lowest since 2010.
For further information on the region's water accounting statements scroll down this page or click on the links below:
Water assets
- Water asset volumes in the region at 30 June 2019 were 12,692 GL, around three quarters of which are surface water assets.
Storages
Figure S1 Total storage volume in the region at 30 June 2019 compared with the previous 9 years
- Storage volumes decreased from 52% full at 30 June 2018 to 32% full at 30 June 2019, the second consecutive annual decrease in storage.
- The end of year storage at 30 June 2019 was the lowest since 2010.
Figure S2 Percentage-full volume on 30 June 2019 for each storage and total storage volume from 2013–2019 (inset)
- Storage volumes peaked in mid-September 2018 following rainfall during the winter months and then generally declined for the remainder of the year.
- Percentage full volumes in major storages in the northern part of the region were generally lower than those in the southern part, which reflects the drier conditions experienced across the north.
- Many storages in the region's north were less than 10% full and at their lowest levels in more than 10 years.
- More detailed information on the individual storages within the region is available on the Bureau of Meteorology's Water Storage website.
Rivers, lakes and wetlands, and other assets
- The volume of water in rivers at 30 June 2019 was well below average, similar to last year, reflecting the very dry conditions across the region over the last two years.
- The volume of water in the region's lakes and wetlands and other assets generally changes little from year to year.
Groundwater assets
Figure S3 Groundwater sustainable diversion limits in the Murray-Darling Basin region
- The groundwater asset volume for the region represents sustainable diversion limit volumes as provided by the Murray–Darling Basin Authority.
- The groundwater asset volume at the end of the year was similar to last year reflecting negligible change to the region's sustainable diversion limits.
Water liabilities
- Water liabilities in the Murray–Darling Basin region refer to the volume of allocation remaining on licence entitlements at the end of the 2018–19 year.
| Description | Individual users (ML) | Urban system (ML) | Environmental purposes (ML) | |
| Opening balance at 1 July 2018 | 3,004,880 | 0 | 898,886 | |
| add | Allocation | 3,863,343 | 574,978 | 1,489,314 |
| less | Allocated diversion | 4,856,869 | 500,364 | 1,237,192 |
| less | Adjustment and forfeiture | 394,537 | 74,614 | 622,407 |
| Closing balance at 30 June 2019 | 1,616,817 | 0 | 528,601 | |
| Description | Individual users (ML) | Urban system (ML) | Salinity and water table management (ML) | Environmental purposes (ML) | |
| Opening balance at 1 July 2018 | 596,403 | 0 | 0 | 15,834 | |
| add | Allocation | 2,086,252 | 80,825 | 39,031 | 54,468 |
| less | Allocated extraction | 1,598,698 | 49,775 | 19,538 | 0 |
| less | Adjustment and forfeiture | (154,416) | 31,050 | 19,493 | 57,365 |
| Closing balance at 30 June 2019 | 1,238,373 | 0 | 0 | 12,937 | |
- Water supply licences for individual users and environmental purposes have carryover provisions, which means a portion of water allocation that has not been abstracted at the end of the water year can be carried over into the next water year.
- There are no carryover provisions for urban system supply, and salinity and water table management licences. 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 Murray–Darling Basin region is given in the Water access and use note.
Water flows
- Total surface water flows into the region's storages was 12,496 GL. The key item contributing to surface water inflows was runoff, which made up almost two thirds of the total surface water inflows.
- Runoff was much lower than average (based on modelled data from 1971–2019) and the lowest in more than 10 years due to the relatively poor rainfall across the region. This was the second successive year of below-average runoff across the region.
- The key item contributing to surface water outflows was evaporation, which made up about a quarter of the total surface water outflows.
- Outflow to sea is typically one of the larger flows but in 2018–19 it only made up 10% of the total surface water outflows. Outflow was well below average due to the dry conditions and low runoff across the region.
- A detailed description on all the water flows associated with the surface water and groundwater stores, including consumptive water use, 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.
| Description | Volume (ML) | |
| Closing water storage balance at 30 June 2019 | 12,692,436 | |
| less | Total inflows | 13,204,785 |
| add | Total outflows | 15,415,860 |
| less | Opening water storage balance at 1 July 2018 | 17,270,185 |
| Unaccounted-for difference | (2,366,674) | |
- The unaccounted-for difference value is primarily attributed to uncertainties associated with the runoff estimate and modelling natural groundwater movement (see Methods), as well as the exclusion of aquifer storage volumes in the account.