Northern Victorian Resource Manager updates 2026/27 Seasonal Determination Outlook
The Resource Manager for northern Victoria today updated the outlook for 2026/27 seasonal determinations.
Northern Victorian Resource Manager Mark Bailey said rainfall since the initial outlook was published in February 2026 had prompted an earlier than scheduled update to the outlook.
“This update is intended to give water users more information about the impact of the rain in late February and early March,” Dr Bailey said.
“At the time, the rain supported improved seasonal determinations this season in the in the Goulburn Broken, Loddon and Bullarook systems. In the Campaspe and Murray system, the improvements secured some additional reserves for 2026/27.”
Dr Bailey confirmed the February and March rainfall had little influence on seasonal determinations in 2026/27.
“Without further follow-up rainfall and an increase in the stored volumes, opening seasonal determinations in the Murray, Goulburn, Campaspe and Loddon systems remain likely to be low," he said.
“There are small improvements in the outlooks for the Murray and Campaspe systems, which reached 100 per cent HRWS this year and had started building reserves for 2026/27. The Goulburn and Loddon systems have changed little.
“Early season announcements in the Broken and Bullarook systems will be influenced by the volumes carried over and the catchment conditions. Each system is likely to start at zero per cent HRWS."
The risk of spill in the Murray, Goulburn and Campaspe systems at the start of 2026/27 will depend on how much water is released from the storages in the next few months.
The risk of spill in the Murray system is expected to be about 35 per cent at the start of July 2026. In the Goulburn system, the risk is currently close to 10 per cent, and 30 per cent in the Campaspe system.
“Customers in these systems should factor the risk of spill into their plans for the remaining months of 2025/26,” Dr Bailey said.
Further Detail on Outlook for the 2026/27 Season
The outlooks for 2026/27 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, Campaspe, Loddon, Broken and Bullarook systems.
Murray System Outlook for Seasonal Determination of High-Reliability Water Shares
| Wet |
2021/22 |
49% |
79% |
100% |
100% |
| Average |
2023/24 |
37% |
49% |
92% |
100% |
| Dry |
2024/25 |
17% |
38% |
54% |
73% |
| Extreme Dry |
2006/07 |
12% |
32% |
38% |
41% |
Goulburn System Outlook for Seasonal Determination of High-Reliability Water Shares
| Wet |
2010/11 |
40% |
81% |
100% |
100% |
| Average |
2023/24 |
12% |
41% |
77% |
100% |
| Dry |
2018/19 |
0% |
15% |
35% |
44% |
| Extreme Dry |
2006/07 |
0% |
1% |
7% |
12% |
Campaspe System Outlook for Seasonal Determination of High-Reliability Water Shares
| Wet |
2016/17 |
100% |
100% |
100% |
100% |
| Average |
2023/24 |
24% |
76% |
100% |
100% |
| Dry |
2018/19 |
16% |
22% |
34% |
40% |
| Extreme Dry |
2006/07 |
16% |
16% |
16% |
16% |
Broken System Outlook for Seasonal Determination of High-Reliability Water Shares
| Wet |
2022/23 |
46% |
55% |
100% |
100% |
| Average |
2023/24 |
0% |
45% |
100% |
100% |
| Dry |
2024/25 |
0% |
0% |
0% |
12% |
| Extreme Dry |
2006/07 |
0% |
0% |
0% |
0% |
Loddon System Outlook for Seasonal Determination of High-Reliability Water Shares
| Wet |
2016/17 |
40% |
81% |
100% |
100% |
| Average |
2000/01 |
12% |
41% |
77% |
100% |
| Dry |
2018/19 |
0% |
8% |
30% |
44% |
| Extreme Dry |
2015/16 |
0% |
0% |
0% |
0% |
Bullarook System Outlook for Seasonal Determination of High-Reliability Water Shares
| Wet |
2016/17 |
0% |
100% |
100% |
100% |
| Average |
2021/22 |
0% |
100% |
100% |
100% |
| Dry |
2008/09 |
0% |
0% |
0% |
0% |
| Extreme Dry |
2024/25 |
0% |
0% |
0% |
0% |
Additional outlook scenarios for each system are available from the NVRM website Additional Scenarios webpage.
Upcoming Resource Manager Announcements
- The 2026/27 seasonal determination outlooks will be updated on Friday, May 15, 2026.
- The first 2026/27 seasonal determination announcement will be released on Wednesday, 1 July 2026 and will include an updated outlook and an assessment of the probability of spill in the Murray, Goulburn and Campaspe systems.