About the Basin Plan

Purpose of the Basin Plan

The Commonwealth Water Act 2007² requires the Murray–Darling Basin Authority (MDBA) to prepare and oversee a Basin Plan. This plan is a legally enforceable document that provides for the integrated management of all the Basin’s water resources. Some of the main functions of the Basin Plan will be to:

• set and enforce environmentally sustainable limits on the quantities of surface water and groundwater that may be taken from Basin water resources
• set Basin-wide environmental objectives, and water quality and salinity objectives
• develop efficient water trading regimes across the Basin
• set requirements that must be met by state water resource plans
• improve water security for all uses of Basin water resources.

The Basin Plan will provide the foundation for managing the Basin’s water resources in a way that can be sustained through time and in the national interest.

What will be in the Basin Plan

The Basin Plan will be a single, consistent and integrated approach to managing all the water resources in the Murray–Darling Basin.

The plan will describe the Basin’s surface-water and groundwater resources and explain how they are currently used by industry, environment and all communities, including Indigenous communities, across the Basin.

The central legal requirement of the Basin Plan is to set environmentally sustainable limits on the amount of water that can be taken in future from the Basin’s water resources. Such a limit is known as a ‘sustainable diversion limit’ (SDL).

Using the best and latest scientific, social, cultural and economic knowledge, evidence and analysis, the SDL for the Basin will be set through a process (outlined later in this document) which involves and directly relates to two other key parts of the Basin Plan: the environmental watering plan, and the water quality and salinity management plan. These three elements of the plan will be closely interlinked, as each influences the others.

The Basin Plan will identify key environmental assets and ecosystem functions of water resources that must be protected. It will also identify risks to the condition or continued availability of Basin water resources and provide strategies for managing those risks.
These risks include issues arising from the taking and using of water, the effects of climate change, changes to land use, and lack of knowledge. Risks such as salinity, acid sulfate soils and other factors affecting water quality will also be taken into account. In developing the plan, MDBA will continue to identify new and emerging risks, and work out the best ways to manage them.

State governments remain responsible for securing and providing the volume of water required for critical human needs. However, the Basin Plan will specify arrangements such as the provision of conveyance water for meeting the critical human water needs of those communities dependent on the River Murray system (excluding the Edward–Wakool System downstream of Stevens Weir).

The Murray–Darling Basin Authority must report on the impacts of the Basin Plan as soon as possible after the end of the first 5 years that the plan has been in effect. The MDBA must review the plan at least every 10 years, but proposes to review the plan as part of an ongoing and dynamic process.

What the plan will be based on

As part of the preparation of the Basin Plan, the MDBA will act on the basis of the best available scientific knowledge and socioeconomic analysis.  This will include having regard to social, cultural, Indigenous and other public benefit issues. The MDBA will use the socioeconomic analysis to inform how, where and when water can be delivered to meet environmental requirements.

The MDBA must also consider the likely socioeconomic implications of any reductions in the long-term average sustainable diversion limits.  A report on the socioeconomic implications will be provided to the Murray–Darling Basin Ministerial Council when the proposed Basin Plan is provided to the council for comment.

Stakeholder input will be an important contribution to the Basin Plan, including through the formal consultation processes mandated in the Water Act.

Current scientific understanding and technical capacity vary greatly across the many different issues covered in the Basin Plan. In cases such as salinity, there is considerable scientific knowledge to be drawn on; in others — such as environmental response to changes in water availability, the extent of connections between surface and groundwater, or future climate conditions — far less information is available or the uncertainty is higher.

Climate change and variability over millennia mean that historical records cannot be relied on for predicting future conditions, so it will be necessary to draw on climate modelling scenarios, to understand possible impacts on the Basin’s water, and to develop adaptive water planning arrangements accordingly. All this calls for a strategic approach to consulting and gathering information on which to develop the first Basin Plan and provide the basis for future plans.

Much valuable information already exists that can be used to help develop the Basin Plan: for example, CSIRO’s Murray–Darling Basin Sustainable Yields Project, and MDBA’s Sustainable Rivers Audit.

Beyond these two major studies there are numerous datasets, reports and other information that will be useful in developing particular components of the Basin Plan. MDBA will draw on all these resources — from scientific and research groups, universities, state agencies and the cultural knowledge of Indigenous communities — for the best, most up-to-date information.

² All Acts referred to are Commonwealth Acts, unless otherwise specified.