Divert the Clarence River into the Darling River
by Ron Row
FISH KILL SHOWS MURRAY-DARLING BASIN AUTHORITY FAILURE
Numerous dead fish now floating down the Darling River and in the Menindee Lakes is more evidence that the Murray-Darling Basin Authority (MDBA) has mismanaged the basin, as the CEC has long documented. So-called “environmental flows” since the MDBA’s notorious “Basin Plan” commenced in 2012 have flushed precious water into swamps and out to sea, and in the process caused riverbank erosion previously never seen.
Now there’s no water left when it’s needed most! And the failure to build the Clarence River Scheme—which has been on the books in some form since at least the early 1920s—means that water from the flash flooding that hit the Clarence Valley in October 2018 did not get to flow down the Darling River.
As of 22 January, the Menindee Lakes held a mere 3.6 per cent of their capacity. The lakes have an official nominal combined capacity of 1,731 gigalitres (GL), three and half times the capacity of Sydney Harbour, but during floods can fill to more than 2,000 GL. Under the “environmental flow” regime, water may be released to leave a mere 480 GL (28 per cent) in the lakes.
Environmental releases from the lakes have enraged many locals at Broken Hill who depend on the water. They blamed a release of about 300 GL in late 2012 and early 2013 as contributing to the lakes running dry. Dam levels recovered in 2016 with good rains from August through to December.
But from mid-December 2016 to present, dam levels have continuously trended downwards. Despite this, in October 2017 the MDBA ordered the release of about 70 GL of water, much to the horror of many locals as the ABC’s Sofie Wainwright reported from Broken Hill at the time: “Given that Lake Victoria is 99 per cent full and there’s more than 90 per cent water in Lake Hume, I was hoping that they wouldn’t be considering [releases] until 2018”, Lower Darling irrigator Rachel Strachan said.
These “environmental flows” were never based on sound science. Numerous reports identify that some of these flows are so damaging that several metres of river frontage are lost to erosion. Riverside trees collapse under these man-made floods and silt has been clogging up pumps and tanks at rates never seen before. The CEC reported in a media release on 14 December 2010 that Snowy Hydro, in government mandated “environmental flows”, was releasing 4,000-5,000 ML/day into the already flooded Murray and Murrumbidgee rivers, risking increased flood damage.
As bad as the current fish kill is, any simplistic talk of blaming “climate change” or “over-allocation of water rights” to irrigators ignores historical facts. The Age of 11 February 1903 reported that one Captain Anderson had recently described thousands of dead fish in the Darling River, “nearly all of them very large ones, on the surface of the river”.
The Bathurst Times of 11 November 1914 reported that in the Darling River, “the fish were dying in thousands”. The Murray Pioneer of 4 June 1920 reported: “The River Darling is reputed to have recently reached the lowest ebb ever witnessed by the oldest inhabitant along its banks. … [It] had the effect of killing large numbers of fish in and around Wilcannia.”
In the NSW Parliament’s Hansard of 16 October 1929, member for Murray Mat Davidson referred to “the fact that an excessive number of dead fish are being carried down the Darling River”. The Barrier Miner (a Broken Hill newspaper) of 8 November 1929 reported the Darling River was very low and dead fish, some as large as 50 lb (23 kg), floated down the river from above Wilcannia (130 km north-east of Menindee) to Cal Lal (on the Murray River about 10 km from the South Australian border).
“The cause of death is a mystery. One man, speaking on the matter, said: ‘Of late there have been more dead fish than water coming down’.” The Dubbo Liberal of 30 January 1951, with an article headlined “Darling River Smells of Dead Fish”, reported that “The death of so many fish will mean years must elapse before they breed sufficiently to replace losses.”
Authorities were unable to explain the cause of this colossal fish kill.
Blue-green algae (cyanobacteria) are said to be the cause of the present fish kill. Warm conditions and low water levels assisted a massive bloom, but a cold front hit the region and killed the algae. Bacteria feeding on the dying algae sucked the oxygen out of the water.
This killed the fish. But algal blooms in Australian rivers are not a new issue either. As the Wagga Wagga Express of 22 April 1933 reported, a conference of users of Murray River water was held at Echuca to discuss “every aspect of … pollution by algae, and its effect on the public health and the dairying industry”.
The Clarence River Scheme is the answer. It addresses the algae problem too, as Prof. Lance Endersbee described in a speech to the CEC on 23 November 23 1997: “There is the catchment of the Clarence River and it is a wonderful little cup in there and very steep country, high rainfall and one of the highest rainfall areas in Australia, and they get the summer rains from the monsoons coming down and they get the winter rains as well. …
So I have worked out, designed a scheme for the diversion of the Clarence into the Darling. Now, as you know, there are a lot of algae in the Darling…. This would flush all the algae out of the Darling.” Prof. Endersbee went on to explain how hydroelectric generation capacity will make this scheme economic. But the economic advantages don’t stop here! Flood damage in the Clarence region, costing many millions of dollars, will be mitigated in future.
Billions of dollars’ worth of new agricultural products will be generated every year. And rather than wasting $3.1 billion of taxpayers’ money to purchase water, only to flush it into swamps and out to sea, the government could allocate such funds to help improve the lives of Australians for a change!