Sarah Hanson-Young says failure to release data about draining of Menindee Lakes ‘stinks of a cover-up’

This article is more than 1 year old

This article is more than 1 year old

The Greens have accused the federal government of hiding critical information from the Senate on why the Menindee Lakes were drained twice in the last four years, as investigations get under way into what caused around 1 million fish to die.

Further fish kill events are expected later this week as temperatures soar to 45C in western New South Wales.

Angry farmers and Menindee residents are refusing to accept that the event was an inevitable result of the drought, as some of the fish killed were more than 70 years old and had survived several drought cycles.

The issue of management of the lakes, which are used as a major storage for the Murray-Darling Basin, is one of the critical questions in uncovering who is responsible for the environmental disaster.

The federal water minister, David Littleproud, had until 28 November last year to provide the information to the Senate, but as of Monday it was still not available, prompting furious letters from the Greens water spokesman, senator Sarah Hanson-Young, who requested it.

“The government’s refusal to release this information, by order of the Senate, stinks of a cover-up and puts them in contempt of the Senate,” she said.

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“For over six weeks we’ve been waiting for answers from the minister about why water was released from Menindee Lakes twice in three years. We still don’t know how or why those decisions were made. I was concerned about it back in November, and now ,after the death of a million fish, it’s even more concerning.”

A spokesman for Littleproud said the information was taking more time to assemble than expected because it was complex and would be produced as soon as possible.

The information is all the more important as the federal government, with the support of the opposition, has given the thumbs up to the NSW government’s plan to reconfigure the Menindee Lakes as part of a suite of projects to save water in the Murray Darling.

The project involves shrinking the lakes and letting Lake Cawndilla run dry more often. The idea is to reduce evaporation from the shallow lake system, but there are serious questions over whether it will harm the important ecological values of the lake as a fish nursery.

The NSW government can then count the water savings from reduced evaporation toward covering its shortfall of 345GL of water that it still needs to meet its obligations under the Murray Darling basin plan to deliver 1,312GL of water to the environment.

The only other alternative is to buy back water licenses from irrigators – something both the NSW federal governments have been reluctant to pursue.

But as Guardian Australia reported last year, the Murray-Darling Basin Authority’s scientific staff delivered a scathing assessment of the project, which it said could do more harm than good.

The document was part of an earlier Senate demand for papers and paints a picture of a poorly formulated project that lacks scientific rigour.

“Given ecological objectives and targets have not been clearly articulated, the business case has been unable to describe their link with environmental watering requirements,” the MDBA concluded.

It said that further details on how the protection of ecological values of the site was required, warning that the Menindee Lakes system was a crucial nursery for juvenile fish that helped stock the entire river system.

The MDBA said the NSW government’s claim that identified risks were not “intolerable”, was far too high a bar on judging risks to the environment.

It also found the proposal did not fully address potential risks and impacts to downstream water uses, including reliability of supply and water quality.

The Wentworth Group of Concerned Scientists analysed all 36 projects based on public information and concluded that only one met the MDBA’s own stated criteria.

But despite there being serious reservations about the Menindee Lakes project and its efficacy, the government, with the support of Labor, secured in-principle acceptance of the project and changes to the Murray Darling basin plan last year.

Murray-Darling fish kill: authority shelved fish health strategy in 2013 Read more

The NSW state opposition water spokesman, Chris Minns, said Labor would put an end to the Menindee project.

“If we are elected it won’t happen,” he said. “Every piece of evidence says it can’t work and won’t work.”

Hanson-Young said she was worried that by withholding the information, Littleproud was following in the footsteps of his predecessor, Barnaby Joyce, and putting the agricultural sector ahead of the environment.

“Australians want a healthy river system and a government that stands up for the environment. It’s clear this government is concerned about keeping big cotton happy at the expense of the river we love,” said Hanson-Young.

The MDBA will convene a meeting of basin water officials on Tuesday to develop a response to the latest fish deaths.