TASMANIA: by David LeamanNews Weekly
Can the Apple Isle become Australia's food bowl
, October 3, 2009
Tasmanian Premier David Bartlett has a vision: make Tasmania the food bowl for Australia.
This idea builds upon farm policy of the last decade which aimed to double production by 2010. This may or may not be a laudable aim and in his State of the State address to Tasmania's parliament earlier this year he explained how he would amplify the goal. Invest $400 million in irrigation, deliver 250 gigalitres of water, place an extra 200,000 hectares under irrigation and so transform production and value at the farm gate.
Unfortunately, this vision, however desirable, overlooks a few cold facts.
Water is the critical element in any such scheme and Tasmania appears to have plenty. National statistics suggest that Tasmania with 1 per cent of Australia's land area has 12 per cent of the nation's fresh water.
This is true, but statistics can lie. Most of that water is in western Tasmania and not readily available to towns (many very short of water), farms or increased production in the dry eastern half of the island. Much of the populated, farmed and grazed region receives between 400 and 800 mm of rainfall annually. Very few mainlanders suspect this could happen in Tasmania. Hence, Bartlett's schemes.
Perhaps it could work if water was piped across the island? Well, no, because there are a few other problems.
The natural, fertile, food production areas, in northwest and northeast Tasmania, possess good soils and reasonable rainfall but are increasingly given over to plantations due to reduced farm values or returns, investment schemes which distort economics, and the reality that trees also grow well in the same places that potatoes, peas, dairy cows or poppies prefer.
These forest schemes have origins in national reforestation and industrial policies which ignore implications about water use and availability. The result: new farm production goals must be met from central and eastern areas where soils are poorer and thinner and where water supply is crucial. This makes little sense but, when combined with salinity problems and risks, it is plain silly. Salt has been mined in this region and its recent spread has been documented in State of Environment reports, and all this before any water is introduced to mobilise existing salt and create more.
But the new schemes do not propose shipping good water from western Tasmania: they involve using local streams and supplies already committed. For example, Arthurs Lake is to supply 30 GL to the upper Midlands but is already required to back up supply to Great Lake, for Hydro Tasmania and irrigation at Cressy-Longford, and in recent years this has been a struggle.
The South Esk River likewise is officially admitted to be over-allocated in a draft water management plan, but is apparently able to supply 9 GL to new investors or farmers. Multiple counting in any situation is a recipe for disaster - personal, business, environmental - but is worsened by administration which ignores long-term climate trends already evident, and realistic estimates of supply security. At the very least, the present dream is unrealistic and inequitable since only those last in, and paying the most for water, will get any.
All these issues have arisen with the first scheme of this type: on the Coal River, a previous political promise and completed in 1985. A very arid area has been converted to viticulture, orchards and vegetable production with substantial investment.
Sadly, no one bothered to consider the safe long-term supply level and, by 1996, the system was clearly over-allocated and would have collapsed completely in 2008 without an emergency piped supply from Hobart Water. Much economic distress threatens.
At the same time, the region is a salinity hot spot and this problem is spreading. Realistic and careful management of such schemes is essential and no one should wear rose-tinted glasses. A second politically-motivated scheme, recently opened on the Meander River, is predicated on similar assumptions. Nothing has been learned.
My advice to land-owners today is the same as that given 40 years ago after I was asked to assess the Coal River catchment. Think long, hard and carefully. Matters of soil, soil-water conflicts, crop choice, commercial potential, water costs, proportion of property committed and security of supply must all be integrated. Prices, values and contracts for product can be as fickle as climate; banks tend to be more exacting, as Coal River farmers have found.
Premier Bartlett, however, is operating in a cloud of delusion and hope, and within a regime where comprehensive water planning is lacking. Tasmania now has many mini Murray-Darlings in the making as a result, and this will ruin land and livelihoods. Poor forest policies merely compound the problems for agriculture.
None of this need happen, but stupid, ill-conceived irrigation schemes in the absence of integrated water policies ensure that considerable damage, to land and people, is inevitable.Dr David E. Leaman is a geohydrologist and geophysicist of 45 years' standing. He has lectured at the University of Tasmania, written several books on geology and water, including Water: Facts, Issues, Problems and Solutions (3rd edn, 2007), and continues to conduct research on Tasmanian catchments on a privately-funded basis.