The federal government is committing more than $13 million to allow South Australian irrigators to access the water they buy almost immediately.
Federal Water Resources Minister David Littleproud on Saturday said the coalition's $13.2 million investment in the water trading system will mean water is delivered to irrigators in minutes or hours, not days.
It also aims to support the delivery of the Murray-Darling Basin Plan, will improve intra and interstate water trading and will bring South Australia in line with the rest of the basin states.
"This will make sure crops don't wilt while farmers wait on their water," Mr Littleproud said in a statement.
The South Australian government will contribute $1.47 million to the upgrade with the new system to be fully implemented by June 30, 2021.
The announcement follows the death of up to a million fish in the Darling River at Menindee in NSW nearly three weeks ago which scientists and local residents said was the result of mismanagement of the Murray-Darling Basin Plan.
NSW Regional Water Minister Niall Blair blamed the weather for the mass deaths but also pointed the finger at Canberra and the Murray-Darling Basin Authority for authorising water releases from the Menindee basin to South Australia when water levels were higher.
A report into the plan, released on Friday, found it was at serious risk without reform and called for the Murray-Darling Basin Authority to be split into an agency to help basin states manage the plan and a regulator which deals with compliance.
