Mr Turnbull says the new plan will make every drop of water count. "The most important thing ... is to properly manage [storages] on a uniform basis," he said.
"Ensuring there is compliance, the water sharing plans across the basin so that they're consistent and that they are complied with, that we address over-allocation where it occurs.
"We pump this very large sum of money, there's nearly $6 billion is going to go into making our irrigation systems the most efficient in the world.
"If we want to maintain a big agricultural base in southern Australia, and do so in circumstances where we're going to have less rain and of course hotter temperatures so there will be even less runoff, in those circumstances you've got to use water as efficiently as you can, and this program will do that."