The Australian constitution gives the Australian Government no express legislative power over water—management of water is vested in the states and territories. By 2006, all jurisdictions had agreed to the provisions and objectives of the National Water Initiative (NWI). The state and territory governments determine access to water resources through water plans and the issuing of entitlements, now under an agreed NWI framework that is intended to deliver:
- secure ecological outcomes, by describing the environmental and other public benefit outcomes from water systems and defining the appropriate water management arrangements to achieve those outcomes
- resource security outcomes, by determining the shares in the consumptive pool and the rules to allocate water during the life of the plan.59
For the most part, ‘water for the environment’ is secured by the rules set out in a water plan that in some way limits how much water can be diverted into the consumptive pool (allocated for human use). In a few highly hydrologically stressed systems like the Murray–Darling Basin, additional water for the environment has been sourced from within the pool of water entitlements (Box 4.5).
In addition, the NWI has set out guidelines for a more efficient and effective water market in Australia. The National Water Market System project will help improve water market operations, such that price signals reflect the scarcity of water in Australia. As a result, water should flow to the highest value economic, social and environmental uses.
Although Australian research has documented the ecological consequences of diminished flows of water, the challenge remains of quantitatively relating changes in flow regime (or the benefits of increased environmental flows) to the expected ecological response. Flow recommendations still mainly rely on expert ecological opinion, based on incomplete ecosystem models or limited data.60 The growing assertion and development of Indigenous land and water management, and associated recognition of traditional environmental knowledge, is significant in this regard (Box 4.6).