Australian Government

MURRAY-DARLINGBASIN AUTHORITY

Ref: EC19-000688

Bryce Wilde GPO Box 5341 SYDNEY NSW 2001 nrc@nrc.nsw.gov.au

Dear Mr Wtl'de

Thank you for the opportunity to provide comment on the review of the water sharing plan for the Barwon-Darling Unregulated & Alluvial Water Sources 2012 undertaken by the Natural Resource Commission (NRC). The Murray-Darling Basin Authority (the Authority) welcomes the review and acknowledges the work undertaken by the NRC.

The Basin Plan requires basin state and territory government to develop water resource plans (WRPs) consistent with the requirements set out in the Basin Plan. All WRPs demonstrate how connected water resources are managed and, where required, include specific rules so highly connected resources are managed together. In New South Wales (NSW), water sharing plans are a key component of WRPs.

In February 2019 the Authority issued a statement to reinforce the need for critical reforms to be implemented through accredited WRPs. These reforms are consistent with the recommendations of the NRC in relation to:

enhancing and protecting low flowsimplementing continuous active management to all flow classes at all times toachieve the full range of benefitsimproving Aboriginal engagement and outcomesimproving the management of connectivity across the Northern Basin to support environmental watering events.

To this end, we are working closely with the NSW government to implement commitments in the Barwon-Darling and other northern basin WRPs. The Authority has resolved that prior to making a recommendation to the Minister to accredit WRPs, it will need to be satisfied that these Basin Plan commitments are met.

Office locationsAdelaide, Albury-Wodonga,Canberra, Goondiwindi, Toowoomba(*^) mdba.gov.au

Peta Derham Page 1

Changes to A class pump levels and flow rates

As noted in our submission, the social, cultural and environmental condition of the Barwon- Darling is at its most stressed during and immediately after a dry period. Our assessment has indicated that, since approximately 2000, there has been a step change in the characteristics of flow through the Barwon-Darling, especially towards the downstream end of the river. Cease-to-flow periods are occurring more frequently and are lasting for longer periods.

Not all of this change can be attributed to Barwon-Darling water management. There have been relevant changes made in upstream tributaries that are affecting inflow to the Barwon-Darling. However, our work demonstrates that the changes made to A-class access conditions as part of the 2012 water sharing plan has larger volumes of water to be extracted more rapidly, which has contributed to less water passing downstream of Bourke during dry and low flow periods.

The changes to commence-to-pump thresholds and daily extraction limits for A-class entitlements, recommended by the NRC, would address some of these concerns. The MDBA supports these recommendations as a necessary step towards a sustainable Barwon-Darling river.

Long-Term Average Annual Extraction Limit (LTAAEL)

I draw your attention to some possible improvements in terms of how compliance with the LTAAEL is described in the draft report (for example, section 3.1.4, page 42). We think a useful clarification would be to provide an explanation in relation to how the LTAAEL operates over the long term, and also in a climate-adjusted way on an annual basis. This could be expected to, over time, lessen the misunderstanding that is apparent in some commentary that only a long-term average is used.

Related to this is the choice of tributary inflows that are used to determine each year's annual expression of the LTAAEL (for example, page 97). This is an issue that has been raised by the MDBA in the annual water take reports (refer section 7.2.2 ofhttps://www.mdba.gov.au/publications/mdba-reports/transitional-sdl-water-take-reports)and the recently released "SDL Health Check" report (refer section 7.2, issue number 8, at https://www.mdba.gov.au/publications/independent-reports/sdl-accounting-%E2%80%98health-check%E2%80%99-independent-panel-review). Application of the appropriate Barwon-Darling inflows (i.e., those correcting for any enhancements in actual inflows from environmental flows) for the purpose of calculating the annual expression of the LTAAEL is a key risk to Basin Plan outcomes in the Barwon-Darling.

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Aboriginal Engagement

The MDBA supports the draft findings regarding Aboriginal engagement and outcomes. In particular, we support engagement for water sharing plans that complements engagement being undertaken in the development of state water resource plans. We also acknowledge the challenges and further work required to improve access (including physical access) to water resources by Aboriginal people. The MDBA acknowledges that it takes time to realise these matters and encourages the New South Wales state government to continue its efforts.

Thank you again for the opportunity to comment on the review. I look forward to continuing a positive and collaborative relationship with the NRC.

Yours sincerely

Peta Derham / August 2019

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