Tuesday, 23rd February, 2010
By Andrew Robertson The first flow in almost a decade is making its way down the Great Darling Anabranch.
Between 3,000 and 4,000 megalitres (ML) of water a day is flowing into the tributary, courtesy of good rainfall in northern NSW and a decision by the State Government to release billions of litres of water for South Australia.
Water began flowing into the tributary at the end of January after releases from the Menindee lakes were increased to 12,000 megalitres per day, the trigger at which water starts to flow into the anabranch. The 460km long anabranch, an ephemeral stream that starts below the Menindee lakes and winds its way south until it reaches the Murray, once benefited from an annual release of up to 50,000ML from the lakes. But the last release from Lake Cawndilla was in 2002 and the anabranch has been virtually dry since in 2005.
Since 2007 the around 40 property owners who live along the tributary have been relying on a pipeline that connects to both the Darling and Murray rivers for their stock and domestic water. Keith Forster, who owns Bulpunga station, about 50km north of Wentworth, said yesterday that property owners would be eagerly awaiting the flow, which is currently between Wycol and Cuthero stations. "It will be a good event, if it happens," he said.
Mr Forster, who was a strident supporter of the Anabranch Pipeline project, said it was unclear whether the flow would make it to the Murray. In its favour was the removal in recent years of the 17 weir pools that once lined the tributary to supply water to properties. But after years of no releases, Mr Forster said the flow's progress would be restricted by "a fair bit of seepage and transmission losses". "We really don't know how the anabranch will perform," Mr Forster said. "There's nothing to restrict it anymore. "It's very hard to judge but I would imagine it will get a fair way down if not right down." Mr Forster said a running anabranch would provide an enormous boost not only to landholders but also the environment. "The yabbies will come up ... if it runs right through to the Murray we might get some fish."
A spokesman for State Water at Menindee said yesterday that releases from the lakes are now at 16,000 ML/day and have been at 12,000 ML/day or more since February 14. But he said flows into Wetherell were expected to drop off "in the next few days", which would lead to a reduction in flows out of the lakes. "Once Wetherell starts reducing we'll reduce flows downstream as well," he said.