The MDB Basin Plan - Need for a Classification and Regionalisation

The MDB Basin Plan (Basin Plan) is intended to be a strategic plan for the integrated and sustainable management of water resources in the Murray-Darling Basin. The Murray-Darling Basin Authority (MDBA) is tasked with the responsibility to prepare the Basin Plan and is working to a timetable that will produce a proposed Basin Plan by mid 2010, and a formal inaugural Basin Plan in 2011.
The high level purpose of the Basin Plan is to provide for the integrated management of the Basin water resources in a way that promotes the objectives of the Water Act 2007 (Cth).

Main Functions of the Basin Plan

Some of the main functions of the Basin Plan include:

  • Giving effect to relevant international and national agreements / obligations – especially as they relate to environmental assets [e.g. the RAMSAR Convention on Wetlands, Biodiversity Convention, and the Environment Protection and Biodiversity Conservation Act 1999 (Cth)];
  • Setting and enforcing environmentally sustainable limits on the quantities of surface water and groundwater that may be taken from Basin water resources;
  • Setting Basin-wide environmental objectives, and water quality and salinity objectives;
    Developing efficient water trading regimes across the Basin;
  • Setting requirements that must be met by state water resource plans; and
  • Improving water security for all uses of Basin water resources.

In this regard, section 21 of the Water Act 2007 (Cth) regarding the ‘General Basis on which the Basin Plan is to be Developed’ requires that the MDBA and the Minister, in exercising their powers and performing their functions in relation to the Basin Plan must:

  • Take into account the principles of ecologically sustainable development which includes the principle that if there are threats of serious or irreversible environmental damage, lack of full scientific certainty should not be used as a reason for postponing measures to prevent environmental degradation; and
  • Act on the basis of best available scientific knowledge and socio-economic analysis.

The environmental objectives incorporated in the Basin Plan include ‘The Conservation of Key Environmental Assets and Water-Dependent Ecosystems and Biodiversity of the Basin’ by:

  • Maintaining and improving key ecosystem functions and services;
  • Improving their ecological resilience to threats and risks in a changing environment;
  • Setting enforceable limits on the quantities of surface water and groundwater that can be taken from the Basin water resources so as to provide for an environmental sustainable level of take; and
  • Setting environmental watering requirements at a whole of Basin level.

In this respect, a key requirement for the Basin Plan, as specified in the Water Act 2007 (Cth) is to set environmentally sustainable limits on the amount of water that can be taken from the Basin water resources – known as the ‘Sustainable Diversion Limit’ (SDL). The SDL must reflect an environmentally sustainable level of take which must not compromise key environmental assets, key ecosystem functions of the water resource, the productive base of the water resource, or key environmental outcomes for the water resource.

The above paradigm speaks of the need to have a transparent and rigorous process for both the identification and prioritisation of ‘environmental assets and ecosystem functions’, and their associated environmental watering requirements. In this regard the Environmental Watering Plan will contain:

  • Overall environmental objectives for water-dependent ecosystems;
  • Targets to measure progress against these objectives;
  • A management framework for environmental water;
  • The methods used to identify environmental assets that require environmental water;
  • The principles and methods which will set priorities for applying environmental water; and
  • The principles to be applied in environmental watering