A leading Murray-Darling Basin expert has rejected proposed solutions to push more water through, or past, the Barmah Choke on the Murray River.
The Murray Darling Basin Authority has released its six options for dealing with a massive sand slug in the Barmah-Millewa reach of the river, which includes the Choke.
The MDBA said capacity through the Barmah-Millewa reach has been reduced from 11,300 megalitres per day in the 1980s to 9,200ML today.
The six options being explored by the MDBA include stablishing river banks, removing sand, changing the timing of deliveries to SA, and using Goulburn-Murray Irrigation District or Murray Irrigation Limited infrastructure to deliver water.
The sixth option is releasing water via the Murrumbidgee River through the Snowy Hydro scheme.
But Slattery and Johnson director Maryanne Slattery said the issue was best solved with policy changes, examining what the irrigated agricultural sector in the region should look like.
Ms Slattery, a former Murray-Darling Basin Authority environmental water director, said it was hard to see how the MDBA could reconcile its proposed solutions with Basin Plan outcomes.
"Dredging the Choke is bad environmentally, bypassing the Choke with engineering solutions is just awful, environmentally," she said.
"The almond plantations [downstream] are the reason they are having to do this.
"They [almonds] are a sacred cow, there is never any challenge as to whether this is a sensible thing to be doing."
Ms Slattery said the MDBA was "just blindly pursuing incredibly expensive options, which are going to contradict, or reverse, a whole of things that are trying to achieve in the Basin Plan, without examining the policy options first."
A Victorian study had predicted at full maturity, in a dry sequence, there was only enough water in the southern connected system for 40 per cent of the demand from almond plantings.
"These almonds are not going to survive, you can't magic up a whole lot more water for them," she said.
"Putting in this really expensive, government funded engineering solution for an industry that isn't going to survive is just crazy."
There were few planning restrictions in place and the market - "which is being regarded almost as a sentient being" - dictated where water went, to what were regarded as the "highest value crops" and those prepared to pay for it.
"Lets have a public conversation about it, but as soon as you start questioning the sanctity of the market, someone makes a reference to the USSR and shuts off the conversation," she said.
But River Management executive director Andrew Reynolds denied the claims the plans were aimed at helping the almond industr.
The MDBA was looking at ways to simply maintain the flow through the Barmah-Millewa reach and stop the capacity from decreasing further, he said.
"This is needed to supply the entitlements that have always been held below the Choke," Mr Reynolds said.
"There is no pressure to increase the volume of water flowing through the reach - the trade rule in place prevents this.
"The almond industry expansion in Sunraysia has been supported mainly by water traded from the Goulburn and Murrumbidgee rivers, not water through the Barmah-Millewa reach."
The sand now on the riverbed was not only causing potential shortfall issues to farmers, it was also creating environmental and cultural impacts such as loss of fish habitat and erosion within that reach.
NSW irrigator, John Lolicato, Wakool, said the Edward River was classified as a "transportation stream" to get water to SA and there was no reason why the Wakool River could not be used in the same way.
"You just have to stay within channel capacity," he said.
He said MIL had 70 "escape structures," which allowed for water to flow to ephemeral creeks and wetlands, but volumes were too low to use them effectively and get significant flows past the Choke.
He said using the Goulburn River had already been looked at.
'Years ago it was canned, and it'll be canned again now because for the environmental benefit to be gained out of it, compared to the actual cost, is just not achievable.
Removing the sand slug might overcome some problems in the Barmah-Millewa reach, but the river banks were now collapsing between Torrumbarry and Swan Hill.
He questioned the claims about how much water was flowing through the Choke.
"It's 9200ML providing you put 2000ML down the Edward River, which is also collapsing under the pressure - it's got trees falling down, left right and centre."
He said it was possible to push the volumes of water required downstream but environmentally and socially that would only create more problems.
"The bottom line is they are watering a lot of country that should never have had water on it and the river can's sustain the volumes they are trying to poke down there," Mr Lolicato said."
Deniliquin, NSW, private diverter Louise Burge said the decline in Choke capacity could not be looked at in isolation.
"The Barmah choke is near the Cadell Tilt and it is this which shapes flows both in the Murray and Edward-Wakool River system," Ms Burge said.
"Ensuring flow capacity through the system needs to look at multiple options, but even with such options, there are still natural limitations in this part of the Southern Basin."
She said the MDBA needed to have more dialogue with communities and stakeholders on what else could be included in the list of options
Some of the options were already being considered within NSW as part of the Sustainable Diversion Limit Adjustment Mechanisms.
"It makes sense for all parts to be discussed and to work through a comprehensive suite of options," Mrs Burge said.
Almond Board of Australia chief executive Tim Jackson said all the proposals had merit.
"Instead of looking at one option, as a silver bullet, I think there needs to be a far broader approach that can provide water surety for irrigators and also some really good environmental outcomes," Mr Jackson said.
Three years ago the industry adopted a position where there should be a connection between land development approvals and water availability, he said.
"Beyond the due diligence of the investors, who are developing the properties, there clearly needs to be some sort of mechanism where there is a calculation as to the amount of water required for the amount of land being developed.
"No-one is denying the rate of new permanent plantings is going to cause serious concerns around water availability, when we go into dry times again."