The Murray-Darling Basin Authority is checking over its facts and figures, commissioning a review of the science underpinning the plan.

The Basin Authority is specifically looking into the evidence that informed the sustainable diversion limits - the amount of water that needs to be returned to the environment.

Authority spokesperson David Galeano says Griffith University has undertaken a scientific review to identify any new information that could inform the sustainable diversion limits.

“The two sustainable diversion limits that we want to look closer are the Condamine-Balonne sustainable diversion limit - that at the moment it's a 100-gigalitre reduction and to date we've recovered about 40 gigalitres - and the other is what's called the Northern Basin shared zone reduction. Essentially, it's the water required for the health of the Barwon-Darling system,” he told the ABC.

“And the way that one works is that that water for the environment can be recovered from any of the upstream tributaries, and at the moment that number is 143 gigalitres in the Basin plan and about half of that's been recovered to date.”

He says researchers have recommended a range if extra projects.

“They've suggested getting a bit more information on where wetlands are and the extent of wetlands, and having a better understanding of waterholes in those systems during different flow levels,” he said.

“Also, things like having a better understanding of, during inundation, where that water actually goes out over the landscape.”