The Australian Greens expressed disappointment that the Water Amendment Bill 2015 will now pass the Senate with the combined support of Labor and the Coalition.
The Bill sets an arbitrary cap 1,500 gigalitres of water the government can buy back from irrigators in order to ensure environmental flows.
"This Bill is all about Environment Minister Greg Hunt caving in to hardline Nationals. It's a bill all about politics, not good policy," Australian Greens spokesperson for water, Senator Rhiannon said.
"The excuses put forward by the government as to why this Bill is necessary just don't stack up. The government already has the ability to limit water buybacks in the event of extreme circumstances, like droughts.
"All introducing a legislated cap will do is make it impossible for farmers to sell their water entitlements once the government had reached the arbitrary 1,500 gigalitre cap.
"The Murray Darling Basin Plan was developed following enormous amounts of consultation. It shouldn't be kneecapped in this way, through sloppy legislation designed to resolve Coalition tensions.
"Environment groups and Indigenous groups spoke out strongly against this Bill, so it is disappointing to see Labor cave to pressure from some state governments and line up with the Coalition.
"Water management and the protection of the Murray Darling Basin should be driven by evidence based policies, in line with the latest climate and hydrological science," Senator Rhiannon said.
Brami Jegan for Lee Rhiannon 0487 350 880