Opposition water spokesman Peter Walsh said five barrages were installed, through the Lower Lakes system, downstream from Lake Alexandrina.
But up to 950 gigalitres (GL) of water was lost each year, from the Lower Lakes, through evaporation.
“There needs to be a serious examination of the case for removing the barrages and installing Lock Zero, and Friday’s meeting is the ideal time to start the discussion,” Mr Walsh said.
“This is about saving Victorian jobs and Victorian farm businesses from wastefully evaporating out of Lake Alexandrina.”
Mr Walsh said a new lock would mean securing water, going down to South Australia, and would mean no more would need to be taken from agriculture to meet the Murray Darling Basin Plan (MDBP).
Record flood events in the southern Basin in late 2016 saw more than 4000GL flow into the Lower Lakes in two months, yet dredging of the Murray Mouth resumed in January.
Last year, an investigation of the impacts of water recovery under the Murray Darling Basin Plan (MDBP) on Northern Basin communities found it had significant negative impacts on jobs and local economies.
Meanwhile, the National Irrigators Council (NIC) chief executive Steve Whan said ministers should see socio economic data from the Northern basin review as a gamechanger.
“Ministers need to focus on outcomes for river health and the community rather than just ticking off numbers of gigalitres (GL).
“I’m hopeful that despite the sometimes-fractious debate they will do that.
“The socio-economic analysis undertaken by the MDBA as part of the Northern Basin review shows comprehensively, and scientifically, that removing productive water has a negative impact on jobs throughout a region.”
Mr Whan said scientific modelling showed that recovering 278GL in the Northern basin had cost 450 people their jobs.
“Future action needs to be firmly framed around that background - around achieving outcomes without negative community impact.”
He said irrigators wanted to see a genuine triple bottom line outcome out of this process.
“We want healthy rivers and healthy environment; we want basin communities to have bright futures; and we want viable and sustainable irrigated agriculture that can put affordable fresh fruit and vegetables in Australian kitchens.
“It should be acknowledged that irrigators and basin communities are, and continue to, contribute to achieving environmental targets.
MDBA estimated water recovery as at December 31 2016 as being 2,027.6GL, or 73.7 per cent toward the 2,750GL surface water recovery target.
ABS figures also showed significant reductions in the total area being irrigated and the amount of water being used per hectare.