It’s time for Penny Wong to start showing some ticker and greater transparency about the Coorong and Lower Lakes.

Yesterday she appeared to throw in the towel, declaring that there’s insufficient water in the Murray-Darling to save the lakes and the lower Murray.

There are plenty of experts who disagree with her. But in the absence of a proper audit of the available water resources, we have no idea who is right. The stakes are too high for this sort of uncertainty. Both the Liberals and the Greens have demanded an audit to establish whether the 450-500 GL of water necessary to stave off the immediate threat to the Coorong and Lower Lakes is available upstream.

The Australian Conservation Foundation believes there is definitely enough water. What’s lacking is the political will – not just from Wong, but from the Queensland, NSW and Victoria Governments.

According to a study by the ACF’s Dr Arlene Buchan, the 500 GL required by December to prevent irreparable damage to the lakes can be obtained from upstream – much of it from the Menindee Lakes.

There are currently 550 GL of water in the Menindee Lakes – below the level (640GL) at which control of the lakes is taken over by the Murray Darling Basin Commission from the NSW Government. There are persistent allegations from across the political spectrum that the NSW Government is managing the lake’s inflows and outflows to keep it below the MDBC threshold. There is also deep scepticism that the water is “fully committed to human needs” as maintained by NSW Water Minister Nathan Rees. Water from Menindee would provide a substantial contribution to saving the Coorong, and could be replenished from water further upstream. There are at least 1700 GL of water held in storages in northern NSW from heavy rain last year and earlier this year.

The ACF also suggests water loans – if there is no political will to pursue compulsory acquisition of water rights, compulsory loans, with rights reverting to owners once the crisis in the Lower Murray has passed, should be considered, as should more purchases of properties. Purchasing or long-term leasing of properties provides an additional benefit of assisting farmers and irrigators who want to exit the industry, and who would not be able to do so merely by selling water entitlements. There are a number of major properties that are on the market now and have both significant water rights and large storages of water available for release.

What about evaporation and water loss, which would defeat the purpose of buying water a long way upriver? This is another area where we are acting in an information vacuum. But it’s known that releasing a large amount of water at once, in winter/spring, will minimise evaporation. A recent estimate by CSIRO scientist Bill Young was that up to 50% of water released from Menindee would reach the lower Murray.

The information vacuum doesn’t just apply to efforts to save the Coorong and Lower Lakes. South Australian senator Simon Birmingham points out that plans to save the Lakes by letting the sea in and building a weir across the Murray are being prepared without any consideration of the environmental impacts of the inundation, both on the Lakes themselves or upriver due to salinity. Birmingham says he doesn’t know whether there is enough water in the system to save the lakes but he is suspicious about the NSW Government’s gaming of the Menindee Lakes requirements, and wants a full audit of available water resources done as quickly as possible. The Greens’ new South Australian Senator, Sarah Hanson-Young, has made the same call.

As Greg Hunt reminded us today with his somewhat unfortunate comparison of Wong with Saddam Hussein, Australia has international obligations in relation to the Coorong.

The consequences of the failure of Penny Wong and Kevin Rudd to take on the states at COAG earlier this year are now also emerging. Crikey has been told the annual 4% trading cap has already been reached on the Campaspe River in central Victoria, which flows into the Murray, and a major water acquisition has been rejected because it will breach the cap – barely a month into the financial year. Victoria’s intransigence on this issue is now directly exacerbating the crisis in South Australia.

Wong needs to urgently reveal, or commission the MDBC to produce, a comprehensive water audit that will allow us to see the basis on which she appears to have given up on the lower Murray. She also needs to confront the NSW Government and get it to come clean on exactly what is going on with the water at Menindee, and put serious pressure on the Victorian Government to give up its irrigator-inspired obsession with the 4% cap. It’s time for her to start living up to the big reputation she’s somehow earned during her short stint as minister.