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As you enjoy the immense natural beauty of the mountains on the Roof of Australia tour in the Australian Alps, it is impossible not to notice and be impressed by the engineering marvel of the Snowy Mountains Hydro-electric Scheme, one of the most complex integrated water diversion and hydro-electric power schemes in the world.
December 2009
The Snowy Mountains scheme is situated in the Kościuszko National Park. The balance between the Scheme's operations and the surrounding environment was a concern from early on in the construction of the Scheme and continues to be closely monitored. Efforts are made to prevent soil erosion and to monitor the impact on plants and animals.
Senior engineers were always conscious of soil erosion: 'They'd rather see us cut tiny tracks than go in with a dozer. If it looked promising then they'd build the roads in after.' This concern for soil erosion was not always in evidence. Wally Wassermann remembers how in the beginning, the overburden from the construction of the road into Tumut Ponds was just dumped over the side of the very steep incline, causing massive erosion. When the Soil Conservation Service of NSW found out, he recalls they kicked up a stink that the whole Scheme was said to be in jeopardy, and it was subsequent to their intervention that soil conservation measures were applied assiduously throughout the Scheme. (McHugh, 1989: 71)
When roads were built particular attention was paid to batters. The steep cut face was often spread with straw and asphalt to assist rapid establishment of vegetation sown and planted on very difficult slopes.
More than half a million trees, hundreds of thousands of cuttings and 20,000 shrubs were grown in Authority nurseries and planted in the field. About 200 tons of specially selected grass and clover seed were sown and 1,500 tons of fertilisers were used to make sure that new vegetation was established quickly.
In June 2000 the Snowy Mountains Hydro-electric Authority achieved certification to the ISO 14001 standard for ongoing environmental management of the Scheme.
In the formative years of the Scheme, there were critics of its long-term economic viability in view of projected reductions in the cost of production from thermal power plants, as a consequence of increases in thermal efficiencies and the construction of large thermal power stations adjacent to mines supplying large amounts of cheap coal.
As events have proved, the investment in the Scheme for hydro-electricity generation alone has been of great value. This arises firstly from the fact that a large proportion of the costs of hydro works are in the civil works such as dams and tunnels, which have extremely long economic lives compared with thermal plants, and the fact that the operational costs are relatively low, whereas thermal power stations have continuing fuel costs which are subject to the effects of changing economic conditions.
In the mid-1980s, the average cost of energy production by the Hydro Scheme was 2.1 cents per kilowatt hour, less than half the cost of electricity sold to bulk consumers by the Electricity Commission of New South Wales and Victoria that year.
The Scheme was designed to produce peak electricity and good flexibility exists on a short-term basis although it is not able to replace base load generation for prolonged periods. Some increase in the diversion capacity of the Scheme may have been of advantage but channel capacity of the rivers below the outlets of the Scheme as well as irrigation considerations limit prolonged, high discharge operation.
Because of the high degree of regulation of water available through Lake Eucumbene a firm minimum release of water equivalent to 85% of average releases is available each year, which not only allows firm planning for electricity production but also for irrigation.
The water diverted westward from the Snowy, Tumut and other rivers by the Scheme, contributes to the Murrumbidgee Irrigation Area in the dry inland of NSW. Farmlands irrigated by the Snowy water produce millions of dollars worth of crops every year, for the national and international markets. Irrigation sustains dozens of agricultural communities in this region of Australia.
In 1968 an entire town, Coleambally, was created as a result of the new flow of water
The irrigated fruit and grain crops produced in western NSW are worth millions of dollars annually. This photograph shows irrigation canals at a citrus orchard in the Riverina.
Rice is the main summer crop in the Murray and Murrumbidgee valleys of western NSW. Fields, like this one, remain flooded for 4-5 months and therefore need large amounts of irrigation water. Rice is a significant export crop.
The regulation of water provided by the Scheme played an important part to mitigate the effect of very severe droughts in 1967-68 and in 1982-83 in the irrigation areas of south-eastern Australia. In 1982-83, the storage in the Scheme was reduced to 18% of capacity and natural inflows to some irrigation catchments were described as being substantially below those previously recorded over some 100 years of available records.
Subsequent recent years of extended drought in south-eastern Australia, combined with pressure to increase flows to the Snowy River, have seen the Scheme’s ability to provide enhanced flows for environmental and irrigation purposes decline substantially.
2007 saw the lowest snow melt on record in the Snowy Mountains. After 10 years of drought and overuse, Snowy Hydro water levels had dropped to an average of just 12%. The Tantangara reservoir was just 6.4% full, while the massive Eucumbene dam had fallen to 16.8%.
Some prognoses by scientists from the Australian Greenhouse Office and the CSIRO of the effects of climate warming – less snow, more bushfires – paint a bleak picture for the Snowy Scheme. Some estimates predict a high chance of a 20% or greater cut in the region’s water supplies, with consequent serious implications for both the hydro power operations and the provision of inland water flows down the Murray and Murrumbidgee.
The Snowy Mountains Scheme provides about 74% of available renewable energy on the eastern mainland Australian electricity grid and 28% nationwide. This represents a displacement of more than 5 million tonnes of 'greenhouse gases' that contribute to global warming every year. As hydro-generated energy it does not pollute the atmosphere and as it is part of the water cycle, it is renewable. Unlike other renewable energy sources it is easy to store and the water can be used several times as it passes through a series of power stations. In addition, the Scheme's scenic lakes and reservoirs are used for recreation by hundreds of thousands of visitors each year.
Hydro-electricity is a fairly clean and efficient source of renewable energy. The Scheme has, nevertheless, had some direct impacts on the environment.
When dams were built some eco-systems that were habitats for plants and animals were flooded.
The Snowy River and its hinterland have sustained humans for thousands of years. Before European colonists went to the region in the early 19th century, the Indigenous Ngarigo, Walgalu and Southern Ngunnawal people lived and interacted in the region. They fished in its waters and hunted game in the surrounding countryside. Around Jindabyne, the river rocks were used extensively for tool making. Men and women had separate sacred water holes for purification ceremonies. In the warmer months people would travel to the high country to feast on bogong moths.
Aboriginal people from around Tumut and the Monaro lost their land to European colonists long before the Snowy Mountains Scheme started. Those remaining by the end of the 1800s were moved on to missions and reserves. They left many objects and sites of social and spiritual significance. Some were recorded before land was flooded for the Scheme, others remain unknown.
Flooding of Scheme reservoirs has meant these places and objects are lost to descendants of the original inhabitants and to the country. This 19th century Aboriginal grave near Jindabyne was recorded by anthropologist Richard Helms in his article 'Anthropological Notes', Journal of Proceedings of Linnaen Society, 1895.
The creation of the huge Eucumbene, Jindabyne, Blowering and Jounama reservoirs resulted in the flooding of thousands of hectares of land. Two whole towns, Adaminaby and Jindabyne, and numerous farms and homesteads were inundated and thousands of years of Aboriginal history were also lost beneath the waters.
Dom Rankin took this photograph of his family home in Jindabyne with a Box Brownie camera in the 1950s. It was the last time he saw his family home. When the photograph was taken, the building had already been sold to the Authority and was demolished shortly afterwards.
Some people were happy with their compensation and the prospect of moving to a modern town but others grieved at giving up their homes in the national interest. This grief, writes historian Peter Read, is for "lost places" and "lost roots, lost childhood or a lost community".
The new Adaminaby, located several kilometres away from Lake Eucumbene, suffered from physical and economic isolation. The new Jindabyne, in contrast, flourished partly as a result of its proximity to Lake Jindabyne, which provided a new identity and source of income, and partly through its role as a gateway to the main ski fields.
Many other properties across the Blowering Valley were flooded with the construction of the Blowering and Jounama Dams in the 1960s. These included Talbingo Station, the birthplace of renowned Australian writer Miles Franklin, whose forebears moved to the valley in the mid-19th century.
Diverting and storing water for the scheme has changed the nature of the Snowy River and other rivers in the region. At the base of the Jindabyne Dam the Snowy River carries only 1% of the water that it did before the Scheme was built.
In 1998, the New South Wales and Victorian governments set up The Snowy Water Inquiry to find a solution that balanced environmental, economic and social factors. Hundreds of submissions were received locally and from further afield.
The fight was bitter because, as the Commissioner of the Water Inquiry noted, restoration of flow to the Snowy pitted three Australian icons against each other: the river which had been immortalised by Banjo Paterson's poem; the Snowy Mountains Hydro electric scheme which is an engineering and social marvel and generates clean electricity; and the food bowl of the farmlands of the Murray and the Murrumbidgee irrigated by additional flows from the Snowy.
The inquiry found that restoring 30% of the Snowy flows was not economically viable and recommended 15%, along with improvements to irrigation practices in the west. The balance of power shifted markedly in 1999 when a local pro-river independent candidate for the Victorian parliament defeated the sitting government member in the State election and formed an alliance with two other independent MPs to hold the balance of power.
This newfound political power was instrumental in getting Victoria and NSW to commit to funding better irrigation practices in order to return flow to the Snowy, including the enclosure of irrigation canals to reduce evaporation. The governments agreed to restore 21% of the original flow to the Snowy River by the year 2010. Eventually, the river flows will be restored to 28%, which is the minimum amount estimated for the river to return to good health.
The result is evidence of the increased questioning of dry land irrigation and dam construction in Australia and is potentially one of Australia’s most significant cases of environmental rehabilitation.
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Sources:
Snowy Hydro Ltd – www.snowyhydro.com.au
www.powerhousemuseum.com/hsc/snowy/
McHugh, Siobhan. (1989) The Snowy: People Behind the Power (William Heinemann, Port Melbourne, 1989), pp.200-201.
Collis, Brad, Snowy – The Making of Modern Australia (Melbourne, 1988; online 2009) –
www.bradcollis.net/snowy/
Australian Bureau of Statistics, “Special Article - The Snowy Mountains Hydro-Electric Scheme” (1301.0 – 1986)
Australian Department of Culture & Recreation Culture Portal –
www.cultureandrecreation.gov.au/articles/snowyscheme/
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