Oil and gas companies and the agricultural sector will be able to extract billions of litres from Northern Territory water sources as a result of the largest-ever water allocation plan.
The Northern Territory government released the Georgina Wiso Water Allocation Plan on Friday, allocating 210 billion litres of water for extraction per year.
Traditional owners and environmentalists have labelled it the "worst water decision" and scientists are worried it could cause the Roper River to stop flowing.
The Georgina Wiso region covers a large area of the NT, including a significant portion of the Beetaloo Basin where fracking is set to begin.
Almost 160 billion litres have been allocated for agriculture, 20 billion litres for the Aboriginal Water Reserve and 10 billion litres for oil and gas.
Water law and policy specialist Erin O'Donnell said the government's modelling relies on extreme weather events and rain to refill the aquifers.
"The sheer volume of water allocated for consumptive use is extremely large," she said.
"The modelling includes extremely rare and extremely large recharge events, one of which is cyclone Tracy in 1974."
Dr O'Donnell said the government is hoping groundwater will be replenished with large inflow events which "may or may not happen".
"Climate change will certainly increase both the intensity of droughts and floods, but it is likely to increase the time between those large rainfall events as well," she said.
The NT's peak conservation body director Kirsty Howey said the plan could "spell disaster".
"It is reckless, dangerous and goes against the advice of the community, not to mention the most eminent water scientists in the country," she said.
The NT government released a draft version of the plan in December last year, leading 18 scientists to pen an open letter calling the plan "particularly poor and regressive" and in breach of national water planning guidelines.
David Ritchie, the independent officer charged with overseeing the implementation of the recommendations of the NT's fracking inquiry also wrote to the chief minister after the plan was released.
In his letter, he criticised the government for not establishing a water advisory committee and including traditional owners in consultation processes.
"(This) reinforced the perception held by many Aboriginal people in affected communities that the traditional significance of groundwater has been ignored by government and industry," he said.
Professor Sue Jackson says except for a slightly smaller water allocation, not much else has changed since the draft, including consultation processes.
"The robust studies that should have been done have not been done and they promised that those will be done at the very best in you know, within two or three years," she said.
"That's unacceptable, you can't hand out all the water and then do the research later."
The water expert said the Aboriginal water reserve has been allocated but Indigenous groups don't have any means of applying for the water as proposed regulations are still being debated.
"Until they're passed, Aboriginal groups can't actually apply for that water, so it remains hypothetical," she said.
Mangarrayi and Yangman elder and traditional owner for Jilkminggan Jocelyn James said the water levels are changing as climate change persists.
"Our country is crying out for water, they are places with song and story and law, now they are dry so early in the season," she said.
"Still they want more water, more fracking, more land clearing - it is making us sick."
NT Chief Minister Natasha Fyles defended the water plan on Monday, saying she "understands there is criticism" but hard work had gone into the plan.