Overall, there has been some progress and some prudent, if somewhat ineffective, measures have been implemented. Government failure here has been in the familiar tradition of funds being hypothecated without due evaluation, perhaps as temporary fixes or on account of ulterior motives. A fundamental issue is the paucity of reliable scientific information against which to scrutinise decisions, blurring accountability and the cost-effectiveness of investments. Decisions backed by good science-based criteria and well defined trade-offs will improve transparency and help avoid politically-driven motivations (Connell and Grafton 2008). It will also justify difficult decisions that are needed to prevent environmental collapse in the Lower Murray.

Information on water use has been an area of neglect, but has gathered momentum in recent years, as reflected by the investment of $1 billion towards improving water-data quality and metering technology. The National Water Account will be based on a comprehensive ‘geofabric’ — in collaboration between the Bureau of Meteorology, the CSIRO and Geosciences Australia — which will tie together all water information including hydrological flows, water use, climate, and so on (Vertessy 2007). ^[17] The Bureau of Meteorology will also will build upon CSIRO work on the Murray-Darling Basin Sustainable Yields Assessment, commissioned in November 2006 and funded under the Australian Water Fund Raising National Water Standards Program (Vertessey 2008, personal communication). This involves building a ‘supermodel’ to estimate the current and future water availability, and the level of over-allocation, in all catchments within the Basin. A novel component of the model is that it makes use of existing State agency models (CSIRO 2007). This is an important move towards standardising the quality of hydrological information used in assessing land-use changes. It is logical that evaluations are based on a single, comprehensive basin-wide model which can capture whole-of-catchment effects and interdependencies consistently.

A useful extension may be to incorporate on-ground data to reflect tangible outcomes and environmental impacts. This will be possible as improved information of the system comes to hand, which should feed into overall water planning in order to maximise public benefits (Connell and Grafton 2008). For example, the Integrated Monitoring of Environmental Flows program in NSW has been in place since 1997 to monitor the effect of environmental rules in regulated systems in the Barwon-Darling River. Integrating data from such empirical studies would help verify outcomes and provide an indicator of environmental improvement. Data from airborne electromagnetic surveying (AEM) could also be used to supplement knowledge of surface and groundwater connectivity across landscapes at high risk of salinity, and to inform strategic decisions such as reforestation.

A particular challenge to current institutional arrangements relates to water sharing between the jurisdictions. As a condition of the States agreeing to the Basin Plan, existing water-sharing plans will remain in effect until its expiry, even if sharing rules are incompatible with the sustainability principles of the National Water Initiative. This incongruence limits the capacity for effective environmental-water management across the jurisdictions, given that future shifts towards dryer climates will require that water-sharing plans be revised and be responsive to such environmental threats. Adequate revisions will likely inflict major political and economic pain on all parties (Connell and Grafton 2008). However, without the necessary changes it is likely future water security will be compromised, leading to even greater social costs.