Hume Dam airspace management and pre-releases (Vic/NSW) Description Consideration of future airspace management in Hume Dam in which pre-releases could provide enhanced environmental outcomes. When environmental water releases are anticipated, the revised airspace evacuation and filling rules impact on timing of releases and both target airspace volumes and pre-releases. The revised rules create more spill events from Hume Dam than observed in the benchmark model outcomes. Project type Rule changes to both storage targets and release trial. Key criteria and stocktake assessment Confidence Environmental More frequent inundation of larger floodplain-wetland in Upper High outcomes Murray Reach and increase in flows downstream at key times. Environmental outcomes scores are significantly increased above benchmark scores. Information Sufficient but no discussion on water accounting. Reliability of rights Moderate modelled but not reported in documentation adequacy Project progress Business case submitted. Stakeholder engagement delayed, subject to High in-principle approval of business case. Dependency on No direct dependency but will influence RMIF and Barmah-Millewa Moderate submitted account and other downstream project release strategies. projects to achieve outcome Significant Potential adverse downstream landholders’ reaction identified. Moderate identified issues Comprehensive plan for stakeholder engagement strategy required. likely to be Potential for a contingent liability if a challenge as result of flooding. resolved This is likely a risk but needs consideration. River Murray operators have identified the potential to modify Significant issues Moderate not identified in proposed rules to improve outcomes and reduce risks. Further documentation proposed enhancements may require rights reliability to be can be managed underwritten by the Commonwealth Environmental Water Holder. An accounting and rights impact assessment is still required. External risks External risks identified risk mitigation strategy proposed. High – managed for supply The project was modelled as part of initial pack package’ included High ‘10 contribution in the MDBA’s June advice. 70 GL is an Initial estimate directly inferred estimate from MDBA modelling. Further iteration of modelling may potentially boost the project’s supply contribution potential by 5 GL based on expert judgment. Plausible supply 70GL*. High contribution range
Hume Dam airspace management and pre-releases (Vic/NSW) Description Consideration of future airspace management in Hume Dam in which pre-releases could provide enhanced environmental outcomes. When environmental water releases are anticipated, the revised airspace evacuation and filling rules impact on timing of releases and both target airspace volumes and pre-releases. The revised rules create more spill events from Hume Dam than observed in the benchmark model outcomes. Project type Rule changes to both storage targets and release Key criteria and stocktake assessment Confidence Environmental outcomes More frequent inundation of larger floodplain-wetland in Upper Murray Reach and increase in flows downstream at key times. Environmental outcomes scores are significantly increased above benchmark scores. High Information adequacy Sufficient but no discussion on water accounting. Reliability of rights modelled but not reported in documentation Moderate Project progress Business case submitted. Stakeholder engagement delayed, subject to in-principle approval of business case. High Dependency on submitted projects to achieve outcome No direct dependency but will influence RMIF and Barmah-Millewa account and other downstream project release strategies. Moderate Significant identified issues likely to be resolved Potential adverse downstream landholders’ reaction identified. Comprehensive plan for stakeholder engagement strategy required. Potential for a contingent liability if a challenge as result of flooding. This is likely a risk but needs consideration. Moderate Significant issues not identified in documentation can be managed River Murray operators have identified the potential to modify proposed rules to improve outcomes and reduce risks. Further proposed enhancements may require rights reliability to be underwritten by the Commonwealth Environmental Water Holder. An accounting and rights impact assessment is still required. Moderate External risks managed External risks identified – risk mitigation strategy proposed. High for supply contribution estimate The project was modelled as part of initial ‘10 pack package’ included in the MDBA’s June advice. 70 GL is an Initial estimate directly inferred from MDBA modelling. Further iteration of modelling may potentially boost the project’s supply contribution potential by 5 GL based on expert judgment. High Plausible supply contribution range 70GL*. High trial.
SDL-Adjustment-Stocktake-Report.docx