Greens Senator Sarah Hanson-Young and Greens MLCs Greg Barber (Vic), Lee Rhiannon (NSW) and Mark Parnell (SA), were calling for a national approach to the Murray-Darling crisis.

"We're hearing that there is goodwill throughout the entire Murray-Darling Basin to help towards a coordinated solution to this environmental catastrophe," Senator Hanson-Young said.

Senator Hanson-Young said a national approach to the Murray-Darling crisis was the only way that the lower lakes and Coorong would be saved.

"The Murray winds its way halfway across the continent without taking notice of the state borders, so it makes sense to remove these bureaucratic barriers and look at the river as one sick system that needs its environmental health restored," she said.

"Only once the Murray’s health is restored will the communities along it be properly sustained."

Senator Hanson-Young said that although the current Senate Inquiry’s terms of reference were focussed on water management in the lower lakes and Coorong, submissions were needed from scientific experts and communities throughout the Murray-Darling Basin for the best information to be gathered about the river system as a whole.

"All options must be on the table to save the Coorong, and so we must have data and expert advice on the whole river system to which it is connected to assess," she said.