In December 2012, the Murray Darling Basin Plan was signed into law. The Goyder Institute has been involved with the analyses of the consequences of this Plan from very early on. In November 2010, we undertook a science review of the Guide to the Proposed Plan. The draft Basin Plan was subsequently released for consultation in November 2011 and the Goyder Institute established an Expert Panel to review the science underpinning this assessment for the South Australian environmental assets. The Expert Panel recommended that a wider range of possible scenarios be evaluated, including additional volume and the relaxation of constraints, to identify potential opportunities in achieving the water requirements for South Australian environmental assets. Following the modelling of additional water recovery scenarios by the Murray Darling Basin Authority, a detailed evaluation of the model outputs was undertaken by SA Government scientists, and peer-reviewed by the Goyder Institute.

This work by the Goyder Institute provided the South Australian Government with the necessary confidence about the quality of the assessments and the science that was used to underpin policy development, to support the negotiations with the Federal Government for a better plan that delivers enough water for the health of the river and its floodplains. However, the real work has only now just begun. The implementation of the Plan needs to be supported by the best available science, monitoring and modelling tools. The Goyder Institute will continue to support the State Government where appropriate during this important implementation phase of the Plan. 

Peer Review of the South Australian Government Eco-hydrological Assessment of Additional Model Scenarios for the Basin Plan (Project E.1.6)

The Murray-Darling Basin Authority has undertaken new modelling of additional water recovery scenarios that include recovering 3200 GL of water for the environment when key constraints on delivering overbank flows to environmental sites are relaxed. South Australian Government scientists have analysed the MDBA’s new modelling and compared outcomes for key environmental and water quality indicators against the proposed Basin Plan scenario of 2750 GL. The analysis focused on the South Australian River Murray floodplain (including the Riverland-Chowilla Floodplain Ramsar site) and the Coorong, Lower Lakes and Murray Mouth Ramsar site.

The government comparative analysis was peer reviewed by experts from the Goyder Institute for Water Research which found that the analysis and interpretation by the South Australian Government scientists were fit-for-purpose and scientifically defensible.

The findings of the Goyder Institute peer review are available by downloading the Goyder Institute peer review memo.

A summary of the outcomes of the South Australian Government analysis can be viewed at:
South Australian Government Science Analysis of Additional Basin Plan Modelling

   Expert Panel Assessment of the Likely Ecological Consequences in South Australia of the Proposed Murray-Darling Basin Plan (Project E.1.4)

Upon release of the Proposed Basin Plan in November 2011, the South Australian Government sought advice from the Goyder Institute for Water Research on the likely ecological consequences for South Australia of the proposed Plan. Given the very limited time available to formulate and provide advice, the Goyder Institute assembled an Expert Panel to provide (largely qualitative) advice based on interim reports of the South Australian Government evaluation of the proposed water recovery scenario.

In its report, the Expert Panel:

• Provides advice on the adequacy of the methods used by the South Australian Government to evaluate performance of the proposed Basin Plan against EWRs;
• Evaluates the likely ecological consequences of the modelled 2800 GL water recovery scenario relative to a baseline scenario;
• Provides advice on how ecological risks could be mitigated to enhance ecological outcomes from the proposed Basin Plan.

The overall conclusion of the Expert Panel was that there were important benefits identified under the proposed water recovery scenario, however, for much of the area of the floodplain environmental assets that require medium to high flows, the environmental water requirements are not met. Thus, the ecological character of the South Australian environmental assets, as defined in current water management plans, is unlikely to be maintained under the proposed scenario. The Panel recommended that a range of options should be explored that support management of the environmental assets such that their ecological function in the longer term is protected.

The report of the Expert Panel Assessment (Technical Report Series Nr. 12/2) can be downloaded here from our website.

The technical reports of the South Australian Government Basin Plan Science Review can be found on the Water for Good website. [external site]

Science Review of Implications to South Australia of the Guide to the Proposed Basin Plan (Project E.1.1)

Prior to the release of the Guide to the Proposed Basin Plan in October 2010, the South Australian Government invited the Goyder Institute to determine whether the proposed sustainable diversion limits would meet the Government’s environmental water requirements and improve or maintain water quality. The review was also to assess the socioeconomic implications of reductions in diversion limits to the major water users within South Australia.

The review used the Murray-Darling Basin Authority’s modelling over 114 years and assessed:

• Whether the environmental water required to meet specified environmental objectives could be delivered under the three Guide scenarios
• Whether water quality and salinity targets set by South Australia and the MDBA could be met under these scenarios
• How best to deliver flows that could meet the state’s environmental water requirements
• The socio-economic impacts for South Australia of the three proposed scenarios

The review found that there are environmental, social and economic benefits for South Australia under the Guide’s three proposed scenarios through increased flow volumes in the lower River Murray. It also found that although two of the proposed scenarios had potentially sufficient average annual volumes to meet environmental water requirements, there are existing physical and operational constraints that at times prevent the delivery of environmental water at the required frequency, timing, magnitude and duration for key environmental assets.

The project produced a synthesis report (Technical Report Series Nr. 11/1) that describes the findings of the Science Review. There are four accompanying peer-reviewed technical reports (Technical Report Series Nrs. 11/2, 11/3, 11/4, and 11/5) that describe the methods and findings of the work undertaken. These reports can be downloaded here from our website.

The South Australian Government may use these reports to inform policy and respond to the Murray-Darling Basin Authority's proposed Basin Plan. Indications of how the South Australian Government may use this research can be found in the SA Government background paper to the Synthesis Report [external site]

Technical report 11/5 reviews the science behind the development of Environmental Water Requirements for the CLLMM, which has been published by the South Australian Department for Environment, Water and Natural Resources. [external site]