Northern Victorian Resource Manager Releases 2021/22 Seasonal Determination Outlook
The Resource Manager for northern Victorian water systems today released the first outlook for 2021/22 seasonal determinations.
Resource Manager Mark Bailey said improved water availability in 2020/21 provided the opportunity to build reserves for 2021/22.
“The Murray, Goulburn, Campaspe and Loddon systems have reserves available for 2021/22,” Dr Bailey said. “Opening seasonal determinations in these systems are likely to be less than 25 per cent of high‑reliability water shares (HRWS) without average flows into the major storages before the end of June 2021.”
“We currently expect the Broken and Bullarook systems to start 2021/22 at zero per cent,” Dr Bailey added. “Carried over allocation volumes and catchment conditions will influence early season availability in these systems.
“Carried over allocation is fully deliverable in all systems from July 1,” Dr Bailey added.
“All of the northern Victorian systems are expected to have seasonal determinations of 100 per cent HRWS by mid-December 2021 under average inflow conditions,” Dr Bailey said.
The Resource Manager used climate-adjusted flow records and assumptions about water use to the end of the water year to determine the initial risk of spill in the Murray, Goulburn and Campaspe systems.
“The Murray system risk of spill is currently about 40 per cent,” Dr Bailey said. “The risk is also around 40 per cent in the Goulburn and about 30 per cent in the Campaspe system.
“Customers in these systems may wish to factor this into their plans for the remaining months of 2020/21.”
Further Detail on Outlook for the 2021/22 Season
The outlooks for 2021/22 seasonal determinations are based on historical flow records that have been adjusted to match climate conditions observed since 1975. The outlook scenarios presented are:
Wet Inflow volumes to major storages that are greater in 10 years out of 100
Average Inflow volumes to major storages that are greater in 50 years out of 100
Dry Inflow volumes to major storages that are greater in 90 years out of 100
Extreme Dry Inflow volumes to major storages that are greater in 99 years out of 100
The following tables summarise the estimated high-reliability water share seasonal determinations through the season for each scenario in the Murray, Goulburn, Loddon, Campaspe, Broken and Bullarook systems.
Murray System Outlook for Seasonal Determination of High-Reliability Water Shares
| Wet |
49% |
78% |
100% |
100% |
| Average |
25% |
37% |
74% |
100% |
| Dry |
5% |
20% |
37% |
56% |
| Extreme Dry |
0% |
10% |
14% |
19% |
Goulburn and Loddon System Outlook for Seasonal Determination of High-Reliability Water Shares
| Wet |
56% |
100% |
100% |
100% |
| Average |
32% |
53% |
100% |
100% |
| Dry |
19% |
33% |
45% |
59% |
| Extreme Dry |
15% |
20% |
27% |
33% |
Campaspe System Outlook for Seasonal Determination of High-Reliability Water Shares
| Wet |
100% |
100% |
100% |
100% |
| Average |
14% |
60% |
100% |
100% |
| Dry |
4% |
10% |
21% |
22% |
| Extreme Dry |
4% |
4% |
4% |
4% |
Broken System Outlook for Seasonal Determination of High-Reliability Water Shares
| Wet |
48% |
53% |
100% |
100% |
| Average |
0% |
53% |
100% |
100% |
| Dry |
0% |
0% |
16% |
35% |
| Extreme Dry |
0% |
0% |
0% |
0% |
Bullarook System Outlook for Seasonal Determination of High-Reliability Water Shares
| Wet |
73% |
100% |
100% |
100% |
| Average |
0% |
100% |
100% |
100% |
| Dry |
0% |
0% |
18% |
41% |
| Extreme Dry |
0% |
0% |
0% |
0% |
Additional outlook scenarios for each system are available from the Northern Victorian Resource Manager website ( www.nvrm.net.au/outlooks ).
Outlooks for low-reliability water shares (LRWS) will be prepared during the 2021/22 season if seasonal determination are 100% HRWS and there is the possibility of LRWS being allocated.
Upcoming Resource Manager announcements
- The next 2020/21 seasonal determination announcement will be released on Monday March 15, 2021.
- The 2021/22 seasonal determination outlooks will be updated on Monday May 17, 2021.
- The first 2021/22 seasonal determination announcement will be released on Thursday July 1, 2021 and will include an updated outlook and an assessment of the probability of spill in the Murray, Goulburn and Campaspe systems.