I wonder what will happen if the Murray River runs dry next year? I don't mean completely dry, but rather, if it is reduced to a series of billabongs as it was in 1914 and 1923.
For so many years we have been told that the river environment is in a desperate state because irrigators take too much water, when, in reality, water levels in the river have been kept artificially high. Indeed irrigators in South Australian have been receiving fully 80 percent of their water allocation from storages at the top of the catchment, from water stored in Lake Hume and Dartmouth Dam.
But the past year really has been dry -- it didn't rain or snow much in the Australian Alps in winter and the Murray Darling Basin Commission has been releasing a lot of water as environmental flow.
In October, 2005, the NSW and Victorian governments -- the same governments who this year are complaining their dams are empty -- made the world's largest delivery of environmental water. They let the equivalent of a Sydney Harbor of water flood the Barmah-Millewa red gum forest which straddles the Murray River upstream of Echuca.
The joint release saw 513 gigalitres of water delivered to the forest and the inundation of more than half of the forest floodplain, resulting in greatly improved conditions for wetland vegetation and breeding activity for key wetland fauna according to a Victorian government report.
"Wetland vegetation, including moira grass and the threatened wavy marshwort, responded with significantly improved condition and the flooding waters provided for new growth and canopy regeneration in stressed river red gums", the report said. "The release also triggered large reproductive events in important native fish species such as golden perch and the threatened silver perch as well as in many water bird species, including the great egret, darters, spoonbills, grebes, ibis and cormorants, and the critically endangered intermediate egret".
All this, during one of the worst droughts on record.
Then there is the water being sucked up from regrowth (following the January 2003 bushfires in the upper catchment), new timber plantations, groundwater licenses being activated for the first time, improved on-farm water use efficiency, water recycling, water being evaporated by the Murray Darling Basin Commission's salt interception schemes and also low precipitation.
Given all of these factors, it's perhaps not so surprising that the region has a chronic water shortage.
Prior to this month's Canberra water summit, National Farmers Federation (NFF) executive director, Ben Fargher, said the priority should be to ensure that towns which support regional communities have certainty over water supply. NFF also wants a strategy to "effectively manage core breeding stock, permanent plantings and other production issues in order to protect Australia's agricultural base".
But that's impossible if there is no water.
If the Murray does run dry, farmers and rural communities that draw water from the river will be devastated, but it will not be a disaster for the environment.
Australian rivers have run dry before and the Murray cod will survive in the billabongs.
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