Recognising Aboriginal legal rights to access and manage water is the key to addressing the “unfolding ecological and cultural disaster on the Murray-Darling”, Indigenous nations of the river system say.

“With our rivers facing ecological collapse and our communities on the brink of survival, there is no other option left,” the Murray Lower Darling Rivers Indigenous Nations (MLDRIN) chair, Rene Woods, said.

“Governments need to buy back water for the environment and support First Nations to acquire water for cultural flows, in addition to environmental water.”

The call comes in the wake of the SA royal commission finding gross maladministration, negligence and unlawful actions in the multibillion-dollar plan to save Australia’s largest river system.

“If water resource plans and associated water sharing plans do not protect the recognised native title rights of First Nations, cultural values and the ecological health of these rivers, they are next to useless,” Rene Woods said.

Traditional owners have been calling for an end to “aqua nullius” for some time, raising the concept of cultural flows, defined as “water of a sufficient and adequate quantity and quality to improve the spiritual, cultural, environmental, social and economic conditions of those Indigenous nations.”

Kangaroos compete for the small amount of water remaining in the outfall at Lake Cawndilla near Menindee, NSW. Thursday 17 January 2019. Photograph: Mike Bowers/The Guardian

The royal commission report, released Thursday, said it “appeared unconscionable that cultural flows have been put at the bottom of the pile.”

“It is difficult to see why there should not now be, after at least six years of research and planning, some real provision for real water rights for cultural purposes incorporated into basin state water management regimes — particularly in areas of severe need, such as the lower Darling River,” the report said.

Four regimes determine Aboriginal water rights in NSW: national water policy, native title legislation, the NSW Water Act, and NSW water allocation planning.

Native title does not include ownership of natural waters. Where native title can be proven to exist, it generally includes rights to take and use water for only personal, social, domestic and cultural purposes.

The majority of NSW’s water sharing plans have zero allocations for native title.

In the Barkandji case, the plan commenced more than a year after their native title determination was handed down, but still said “at the commencement of this plan, there are no native title rights in these water sources. Therefore the water requirements for native title rights are 0 ML/year”.

Traditional owners have also suggested the establishment of an independent Indigenous water fund or trust to allow Indigenous nations to participate in the water market and allocate water to meet self-determined objectives.

The royal commission report supported these concepts but said the “elephant in the room for all basin states: where will water for cultural flows come from, in a largely over-allocated system? Or, perhaps more accurately, who will pay for it?”