Each of the projects put forward by Basin state governments, as part of the sustainable diversion limit adjustment mechanism package were subject to rigorous feasibility assessments by all Basin states, the Commonwealth and the Murray–Darling Basin Authority (MDBA).
The status of these projects vary, with some projects at the early stages of project design and community consultation, with others already fully operational. Regardless of the status of the project, each measure underwent the following phased assessment process set out in Schedule 1 of the Intergovernmental Agreement on Implementing Water Reform in the Murray–Darling Basin 2013 as agreed to by all Basin states and the Commonwealth.
Phase 1 – Feasibility
During the feasibility phase, Basin state governments identified and submitted potential proposals with the most potential to achieve effective outcomes for further evaluation. The proposals were assessed for technical feasibility, feasibility within the estimated cost, and the likelihood of achieving the stated outcome. Based on these assessments, the Basin Officials Committee (BOC) approved viable proposals to progress to Phase 2, Business Case development.
Phase 2 – Business case
Basin state governments prepared a high-level business case for each proposal. Business cases were assessed on their likelihood to achieve the intended outcomes of the project, as well as their assumptions, benefits, costs and risks. Additional evidence such as extensive technical analysis and documentation were also considered. A risk profile for each project was developed, and where relevant, technical analysis and documentation were provided.
Phase 3 – Confirmation
Phase 3 required the proponent to demonstrate that Commonwealth and/or state funding for each project was agreed in principle, with final funding arrangements for new projects subject to the delivery of project outcomes.
The confirmation statements will also provide evidence that all works approvals, environmental approvals, cultural heritage management plans and other regulatory requirements are in train.
Sustainable diversion limit adjustment mechanism process
The MDBA's role in the assessment process
The MDBA provided a technical analysis of projects to support Basin governments in their assessment of project feasibility studies and business cases.
The MDBA also administered the sustainable diversion limit adjustment assessment framework, designed in collaboration with Basin governments and the Commonwealth Scientific and Industrial Research Organisation (CSIRO), to determine the environmental equivalence from the final package of state projects and recommend an adjustment volume for sustainable diversion limits. The framework was trialled and thoroughly reviewed by independent experts, and found to be scientifically rigorous and fit for purpose. Basin governments were also extensively involved in the development of the framework.
Based on the package of measures notified by Basin state governments to the MDBA, the MDBA determined the sustainable diversion limit adjustment volume in September 2017. In December 2017, this adjustment was proposed and adopted as an amendment to the Basin Plan by the Commonwealth Minister responsible for Water.
Review of the SDL adjustment assessment process
In May 2018, Australian Senator Rex Patrick requested that the MDBA obtain and provide independent advice on the process to assess the individual projects that contribute to the adjustment of sustainable diversion limits in the southern Basin. The MDBA appointed an independent panel to review this process for consistency with the requirements of the Water Act 2007, the Basin Plan 2012 and the Intergovernmental Agreement on Implementing Water Reform in the Murray–Darling Basin.
The panel found that the processes established and followed were consistent with the requirements of the relevant legislation and agreements. The panel presented its findings at the first technical workshop and provided recommendations on the implementation of the sustainable diversion limit adjustment mechanism projects going forward.
