The Goulburn to Murray trade review Scientific Advisory Panel (the Panel) has completed the 2021-22 annual report describing the environmental outcomes from the first year of a three-year environmental monitoring program. The monitoring program is designed to assess the environmental performance of the new long-term Operating Rules for the Lower Goulburn River, to determine whether the rules are working as expected to prevent the kinds of environmental damage seen in previous years due to sustained high flows over summer and autumn. 

The 2021-22 results provide some early indications of positive environmental response in the absence of sustained high flows on the river in each of the core themes described below:

Bank condition: Less erosion was observed and there was evidence of repair to past erosion following deposition of sediment and establishment of vegetation at some sites surveyed. While some notching was observed, highlighting the importance of flow variability, the initial results suggest that the baseflows specified in the operating rules are likely to limit further damage to bank condition and may lead to longer term repair.

Bank vegetation: There was a marked increase in the cover of native inundation-tolerant vegetation along the lower bank zones. Further monitoring is required to see how the vegetation will respond to the delivery of summer pulses however the initial results suggest that the baseflows specified in the operating rules are likely to facilitate a recovery of bank vegetation.

Native fish: Increases in the number of native fish suggest lower summer baseflows may provide more favourable conditions for the spawning and recruitment of the Murray River rainbowfish and Australian smelt species, however further research is required to understand if the new operating rules are facilitating the recovery. 

Macroinvertebrates: An increased abundance of shrimp and prawns was observed in 2021-22 compared to previous years, suggesting a positive response by macroinvertebrates to low summer baseflows. Further research is required to understand this trend and the impact of the new operating rules.

Platypus: There is little information on platypus numbers in the lower Goulburn River, but early survey results suggest that platypus may be more widely distributed downstream of Goulburn Weir than previously thought (albeit in very low numbers), supporting the importance of understanding the impact of the new operating rules, particularly during the critical summer platypus reproductive period.

Baseline monitoring of the environmental condition of the lower Broken Creek was also undertaken. The Panel recommends further monitoring and investigations be undertaken in the lower Broken Creek in combination with the Goulburn to Murray trade review monitoring program to better understand what impacts the new trade and operating rules may be having on the lower Broken Creek. 

For more information about the 2021–22 results and analysis, see the full reports below:

Download PDF Scientific Advisory Panel Annual Report Number 1—Overview of the 2021–22 Lower Goulburn River Research and Investigations Program (3,003 KB)

Download PDF Scientific Advisory Panel Annual Report Number 1-A—Detailed Results from the 2021–22 Lower Goulburn River Research and Investigations Program (9,011 KB)

Download PDF Scientific Advisory Panel Annual Report Number 1-B—Detailed Results from the 2021–22 Lower Broken Creek Research and Investigations Program (3,475 KB)

Download PDF FAQs—The 2021–22 Scientific Advisory Panel Reports (80 KB)

The Panel will continue to use monitoring results to assess the environmental performance of the long-term operating rules over the next two years of currently funded monitoring, gathering evidence to support any recommendations regarding future refinements and improvements to the rules. 

You can read more about the Goulburn to Murray trade review and the Victorian Minister for Water’s decision on long-term trade and operating rules here.