URGENT action is needed by all state governments to ensure the Murray-Darling Basin Plan is realised, the National Water Commission warns in a report released on Tuesday.
The report, tabled in parliament, puts on notice all governments to act on the plan, not simply let it gather dust.
Commission chair Karlene Maywald said the plan was a major step in the way water resources were governed in the country's largest basin.
She said it was now up to all basin governments to honour the 2008 inter-governmental agreement on basin reform, to ensure the plan was actually delivered.
The commission's warning comes as it prepares the priority areas it will focus on in the first full audit report of the basin plan, due out in 2015.
Ms Maywald said the latest report called for strong leadership and a sustained commitment of resources to the plan.
"Significant investments by the Australian and state governments have already established a substantial volume of recovered and held water that is available for environmental use," she said.
"However, there is now an urgent need for governments and their agencies to map a clear implementation pathway showing how they will deliver on the plan's requirements."
Ms Maywald said until the framework was in place, there was a real risk to realising the plan, potentially wasting the billions already invested.
"Tangible evidence of progress will be vital in building trust in the plan's ability to secure good outcomes for the basin and its communities," she said.