Final 2020/21 seasonal determination update
The Resource Manager for northern Victoria today announced the final 2020/21 seasonal determinations.
The seasonal determinations in the Murray, Goulburn, Campaspe and Loddon systems remain unchanged at 100 per cent of high-reliability water shares (HRWS).
The Broken and Bullarook systems remain at 100 per cent HRWS and 100 per cent of low‑reliability water shares (LRWS).
Resource Manager Mark Bailey said while seasonal determinations were unchanged, recent rain provided small improvements to reserves for next season.
“Storage evaporation and river losses reduced and there was a small increase in flows into the major storages following rain in the past fortnight,” Dr Bailey said. “These improvements contribute to the reserves for seasonal determinations in 2021/22.”
"The outlook for 2021/22 seasonal determinations will be next updated on Monday May 17, 2021."
The Bureau of Meteorology seasonal rainfall outlook favours slightly above-average rainfall across northern Victoria for the three month period from April to June.
“The Bureau says most El Niño–Southern Oscillation indicators have returned to neutral levels,” Dr Bailey said.
The seasonal determinations for northern Victorian water systems on Thursday, April 1 are:
Murray |
100% |
0% |
Broken |
100% |
100% |
Goulburn |
100% |
0% |
Campaspe |
100% |
0% |
Loddon |
100% |
0% |
Bullarook |
100% |
100% |
Trading opportunities
Allocation trade from New South Wales to Victoria is limited to the lesser of a net annual volume of 200 GL or a volume that keeps the risk of spill in the Victoria’s share of the both Hume and Dartmouth reservoirs below 50 per cent. The current risk of spill in the Murray system allows 200 GL of net trade from New South Wales to Victoria. Customers can find out more about trade adjustments on the Water Register website.
The Goulburn system’s inter-valley trade (IVT) account owes about 178 GL to the Murray system. Deliveries from the Goulburn IVT account to the River Murray will continue in April, at varying rates depending on demand. The Goulburn, Campaspe and Loddon systems can trade to the Victorian Murray system, New South Wales and South Australia while the total volume owed to the Murray system is less than 200 GL.
Conversely, the Goulburn, Campaspe and Loddon systems can trade from the Victorian Murray system, New South Wales and South Australia while the total volume owed to the Murray system is greater than zero. Customers participating in the water trading market can monitor trade availability on the Water Register website.
The Murray-Darling Basin Authority (MDBA) is restricting trade of water allocations from above the Barmah Choke to downstream of the Choke to protect the delivery of downstream water entitlements. Customers can monitor trading opportunities across the Barmah Choke on the MDBA website.
Upcoming Resource Manager announcements
- The outlooks for 2021/22 seasonal determination will be updated on Monday May 17, 2021.
The northern Victoria Resource Manager today updated 2018/19 seasonal determinations.
The Murray system moves from 94 per cent of high-reliability water shares (HRWS) to 100 per cent HRWS.
The Goulburn system and the Loddon system increase from 88 per cent HRWS to 93 per cent HRWS.
The seasonal determination in the Broken system increases from 24 per cent HRWS to 30 per cent HRWS.
The Campaspe system remains at 100 per cent HRWS and the Bullarook system remains at 100 per cent HRWS and 100 per cent of low‑reliability water shares (LRWS).
Resource Manager Mark Bailey said recent rain helped to improve water availability.
“Most of northern Victoria received some rainfall during the first half of December,” said Dr Bailey.
“The rainfall across the northeast catchments increased the flows into the storages and in the downstream rivers,” said Dr Bailey. “The flows were higher than our conservative estimates, and together with lower evaporation from the storages, provided additional resource to allocate.”
Dr Bailey noted these factors will influence seasonal determination improvements in the coming months.
“The seasonal determination outlook to 15 February 2019 is based on historical flows into the major storages under different scenarios,” said Dr Bailey. “These flows are generally low at this time of year. Seasonal determination assessments include estimates of evaporation and river losses.
“As we have seen, if actual losses are lower than these estimates, more water is available to allocate.”
Dr Bailey noted the climate outlooks for summer rainfall did not favour wetter or drier conditions.
“The latest Bureau of Meteorology seasonal outlook indicates there is an even chance of receiving above average rainfall during the December to February period,” Dr Bailey said. “The Bureau has issued an El Niño Alert, meaning the chance of an El Niño forming in the coming months is around 70 per cent. It is likely that the positive Indian Ocean Dipole is nearing its end, but it has little influence on rainfall from December to April.”
Dr Bailey urged water users to continue planning their water needs carefully. “Websites such as the Resource Manager (www.nvrm.net.au), the Victorian Water Register (www.waterregister.vic.gov.au) and the Murray-Darling Basin Authority (www.mdba.gov.au) provide information about water trends and availability, which can help users plan their use.”
The seasonal determinations for northern Victorian water systems on Monday, December 17 are: