Plans to release more water from the Menindee Lakes have been met with outrage.

The Murray-Darling Basin Authority (MDBA) wants to increase releases of water to meet demand downstream, after letting out about 1.7 gigalitres per day to improve fish habitats for native species in the Lower Darling.

The authority has requested NSW water authorities allow it to release six gigalitres per day in the next week to meet demand from environmental licence holders, irrigators and other groups in the Lower Darling and Murray Rivers.

“[We are] not really sure how much water we'll be able to order from the lakes, because that depends on evaporation, further inflows and local usage,” MDBA director of river management, David Dreverman, told reporters.

“But whatever happens, we can't direct the release [to occur] once the volume in the lakes falls below 480 gigalitres,” he said.

If the level drops below 480 gigalitres, NSW authorities become the only ones able to order releases.

Mr Dreverman said without further inflows over summer, the trigger point could be reached by May.

The Broken Hill and Darling River Action Group says “it's going to be devastating”.

“The economic life of Menindee and the whole lakes area has obviously come alive since the water's come back,” the group’s spokesperson Darryn Clifton said.

“To take that water away stops the tourists from coming.”

Other water-users said they could not understand the logic of pushing a large amount of water into an already-flooded Wentworth system and Murray system.

Previous releases have caused concern in Broken Hill, which must rely on the Menindee Lakes for drinking water until a planned pipeline from the Murray River is constructed.