Water for the Future Moving water long distances: Grand schemes or pipe dreams? Table of Contents The idea: moving water from northern Australia to southern Australia 3 How would water be diverted and moved? 5 Where would the water come from — and is there
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Water for the Future Moving water long distances: Grand schemes or pipe dreams? Table of Contents The idea: moving water from northern Australia to southern Australia 3 How would water be diverted and moved? 5 Where would the water come from — and is there enough? 7 Is moving water from the north to the south possible? 9 Proposals for moving water 9 What does all this mean? 14 Water for the Future 15 Alternatives to diverting water — what else can we do? 15 References 19 Glossary 21 Moving water long distances: Grand schemes or pipe dreams? Published by the Department of Sustainability, Environment, Water, Population and Communities GPO Box 787 CANBERRA ACT 2601 ISBN is 978-1-921733-06-2 © Commonwealth of Australia 2010 Information contained in this publication may be copied or reproduced for study, research, information or educational purposes, subject to inclusion of acknowledgement of the sources. Requests and inquiries concerning reproduction and rights should be addressed to Commonwealth Copyright Administration, Attorney General’s Department, Robert Garran Offices, National Circuit, Barton ACT 2600 or posted at http://www.ag.gov.au/cca The views and opinions expressed in this publication are those of the authors and do not necessarily reflect those of the Australian Government or the Minister for Sustainability, Environment, Water, Population and Communities. While reasonable efforts have been made to ensure that the contents of this publication are factually correct, the Commonwealth does not accept responsibility for the accuracy or completeness of the contents, and shall not be liable for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the contents of this publication. I love a sunburnt country, A land of sweeping plains, Of ragged mountain ranges, Of drought and flooding rains. Dorothea Mackellar (“My Country”) Dorothea Mackellar’s famous poem captures our love of Australia’s landscape. But, it also captures one of our greatest challenges: how to manage our water. Australia is the driest inhabited continent,1 and its rainfall varies greatly from year to year and place to place.2 This means that our water supplies can be scarce and unreliable. Water management is sometimes a controversial topic in Australia — one that generates strong debate and big ideas. This publication looks at one of these big ideas: moving water long distances from northern to southern Australia. It covers the possible costs and benefits of various options, as well as other alternatives for securing water supplies. The idea: moving water from northern Australia to southern Australia News reports often show farmers in southern Australia battling drought, while the towns and cities of the north are inundated with ‘flooding rains’. About 70 per cent of Australia’s runoff occurs in northern Australia,3 and climate research predicts that water scarcity in southern Australia will intensify.4 These facts, along with the existing water pipelines across the country, have led people to suggest that water could be harvested from rivers, streams or storage dams in northern Australia, and transported south, using trucks, ocean tankers, canals or pipelines. Key facts • Moving water long distances is costly, energy intensive, and can have significant environmental, social and cultural impacts. • Using water that is locally available is generally more cost effective than transporting water long distances. Current studies show that local options, such as water conservation, desalination and recycling, cost around $1–2 per thousand litres; a supply from 1500 kilometres (km) away would cost around $5–6 per thousand litres.5 • Much of northern Australia can be described as ‘annually water limited’. This means that in general, more water is lost every year through evapotranspiration than falls as rain.6 • Most rainfall in northern Australia falls near the coast, not in river headwaters, and runs off to the sea. • The landscape across much of the north is gently undulating and at a low elevation, presenting few opportunities for surface water storage such as dams. Has it been done before? In particular circumstances and places, pipelines can be a useful way to improve the availability and reliability of our water supply. Significant infrastructure projects that transport water have previously been undertaken. However, none have been on a scale that would move large volumes of water for such a distance as from northern to southern Australia. Past large-scale projects include the early 1900s 530 km Kalgoorlie Goldfields Pipeline, and the 1960s Snowy Mountain Hydro-Electric Scheme. Many shorter pipelines also exist in Australia. For example, pipelines carry water from the Murray River in South Australia to other parts of the state. The longest of these (from the Murray River) is the 356 km Morgan to Whyalla pipeline, built in 1944. It can transport 206 megalitres (ML) of water a day. Pipelines have also recently been built in response to drought; a 105 km pipeline moves water from the Stirling Dam on Western Australia’s Harvey River to Perth.7 How much water? Litre (L): the volume of water in one-thousandth of a cubic metre. One litre weighs about one kilogram. Kilolitre (KL): 1000 litres or one cubic metre of water. One kilolitre weighs about one tonne. Megalitre (ML): one million litres or 1000 cubic metres of water, weighing about 1000 tonnes. An Olympic swimming pool holds at least 2500 cubic metres or 2.5 ML. Gigalitre (GL): 1000 million (or one billion) litres of water or one million cubic metres. One gigalitre of water weighs about one million tonnes. Sydney Harbour holds more than 500 GL. The Snowy River Scheme The Snowy River Scheme is a major river diversion and a successful largescale infrastructure project. A system of reservoirs, aqueducts and tunnels captures water from the upper reaches of the Snowy, Murray and Murrumbidgee rivers, diverting it for use in irrigation and electricity generation. Almost the entire flow of the Snowy River is diverted west. Legislation to begin the scheme was passed in 1949, and it was completed in 1974. Australians are proud of the Snowy Scheme. It helped to shape our history, with thousands of new migrants beginning their life in Australia working on its construction. The Snowy Scheme, one of the engineering wonders of the world,8 increased the availability and reliability of water in the west; this allowed the development of irrigation-based farming.9 Despite the significance of the Snowy Scheme, it is important to recognise its environmental impact. The scheme has reduced the Snowy River headwaters to around one per cent of their original flow. The upper reaches of the Snowy River, and other mountain rivers diverted by the scheme, are severely degraded. The reduction in flow has impacted greatly on aquatic fauna and flora; temperature regimes have changed, triggers for fish breeding have been removed, and the lack of flushing water flows has resulted in a loss of habitat. Pools have filled in as organic material and nutrients have accumulated. Sediment build up in the middle reaches of the river has destroyed habitat and changed the flow pattern of the water, and seawater intrusion in the lower reaches now affects local landholders many kilometres upstream from the river mouth.10 Scientists estimate that to return the Snowy River to a healthy state, its flow should be returned to a minimum of 28 per cent of its original level. In 2002, the New South Wales, Victorian and Commonwealth Governments signed the Snowy Water Inquiry Outcomes Implementation Deed. This outlines a process to return 21 per cent of average natural flow to the Snowy River over 10 years, with the option of increasing this to 28 per cent after 2012.11 How would water be diverted and moved? Pipelines The most commonly suggested method of transporting water is through a concrete and steel pipe, running either above or below the ground. Regular pumping stations would be required to maintain the pipeline’s flow over a long distance. Pipelines minimise the amount of water lost to evaporation, because the water is not exposed to air or sunlight. Pipelines can also help to maintain water quality. However, the water may still need to be treated at both the source and at the end point, with any treatment processes adding to the significant energy and greenhouse costs of piping water. A pipeline from the north to the south of Australia would rate among the longest water transfer projects in the world. Some people have suggested that pipelines could supply water to towns and agriculture along the way, for irrigation, native vegetation, or town and community water supplies. The economic, environmental and social costs of pipelines and other water transport options all vary, depending on factors such as the amount of water to be diverted, and the path the pipeline would take. A report to the Western Australian Government about piping water from the Kimberley to Perth found that it was not an economically viable option. The cost of water transported through a pipeline or canal, in that instance, would be between 100 and 200 times more than normal prices for bulk water.12 What about gas pipelines? Many people see long gas pipelines, and wonder why similar pipelines aren’t built for water. Although water is much less expensive than gas, it is much heavier, and therefore requires much more energy to move. For example, you can buy a nine kilogram (kg) cylinder of gas for about $30 from your local service station and easily carry the gas home. But imagine that you decided to buy water instead. For $30, assuming you paid the same price as you pay for water from the kitchen tap, you’d have to transport about 42 000 L of water — enough to fill a backyard swimming pool! Trucking and shipping water Trucks or ocean tankers could be used to transport water from the north to the south. These options would have large operational costs and energy requirements, and would generate large amounts of greenhouse gases. Trucks are often used to transport water to towns in times of drought. However, this is only viable as a temporary water supply option and when carting over short distances. Canals Some people have suggested that water could be transported long distances across Australia by canals, which are open channels cut through the land. A small slope can be enough for gravity-fed movement of water through a short canal. However, as is the case for pipelines, pumping would be required to move water through canals over longer distances. A canal needs to follow the contours of the land. This means it tends to be much longer than a direct pipeline. For example, a direct coastal route from the Kimberley to Perth is 1900 km long, but a canal would have to follow a 3700 km long route. A canal would also need to pass over or under roads, rivers and other obstructions. See Figure 1 for the length of other options. Canals lose water through leakage and evaporation. A 3700 km long canal from the Kimberley to Perth could lose 93 GL per year to evaporation, and a further 125 GL per year to leakage, even if the best lining techniques are used. To account for these losses, such a canal would need to draw at least twice as much water as is needed for consumption. To prevent seepage and minimise friction, canals are often lined with concrete. Fencing may also be required to help minimise water contamination, or to provide safety barriers. These factors add to the expense of canal construction. Canals leave a lasting and permanent mark on the land, and they change and disrupt natural water flows.13 Figure 1: Diagram comparing distance of some proposed and existing projects to transport water 
Where would the water come from — and is there enough? Proposals to transport water from northern Australia vary, but they all rely on excess water being available for extraction. This depends on a range of factors, including: • the reliability of rainfall across northern Australia • the current and likely future availability of water in northern Australia • the current and potential future uses of the north’s water resources • the practicality of capturing and storing water before being diverted, and • environmental, cultural, economic and political considerations. Rainfall in northern Australia Rainfall patterns in northern Australia are very different from those in southern Australia. The seasons of the northern Australian tropics can be loosely divided into two distinctly different periods — wet and dry. During the dry season, which lasts up to nine months of the year, there is little or no rain. In fact, in many parts of northern Australia, evapotranspiration is higher than rainfall for most of the year.14 Water scarcity can be an issue for communities and ecosystems. People living in the tropics use dams and bores for their water supply to cope with these unreliable and seasonal rainfall patterns. During the wet season, the north can receive extreme rainfall from thunderstorms, monsoon depressions and cyclones. For a few months each year, more rain falls than is lost to evaporation. This rainfall accounts for around 65 per cent of Australia’s total water runoff. The north’s annual runoff can occur over just a few days. Most of this water runs to the sea, but some plays an important role in the annual recharge of aquifers (geological formations that hold groundwater).15 When people hear that a large amount of Australia’s rainfall runs off into the ocean, they sometimes think that this water is ‘wasted’. However, it is important to remember that this water is vital to the health of ocean ecosystems and estuaries. Also, because rainfall in the north is highly variable, both within each year and from year to year, estimates of annual average rainfall for the north can be quite misleading. A single extremely wet year can dramatically increase the long-term average.16 Rivers and catchments in northern Australia Northern Australia has the largest area of unregulated rivers and catchments (those without dams or water extraction) in Australia. Most estuaries are in a near pristine condition, because human land use has had minimal impact, and pests and weeds are not widespread.17 Floods are vital ecosystem events that flush nutrients into the near-shore marine environment and provide on-shore breeding grounds for marine creatures. When water flows over riverbanks and across floodplains, it fills hollows and pools that persist throughout the dry season. This sustains vital ecosystems that provide refuges for birds and animals until the next wet season.18 Large amounts of runoff can also trigger waterbirds to breed, and fish to spawn and migrate.19 The health of northern ecosystems has direct economic implications for the value of northern fisheries. Just one of these, the Northern Prawn Fishery, is worth up to $164 million per annum.20 The Ord River and Lake Argyle Lake Argyle, on the Ord River in Western Australia, is often cited as a potential source of water for southern Australia. It has a capacity of 10,700 GL (about 21 times the size of Sydney Harbour). However, the Western Australian Government has shown that if the planned expansion of the Ord River irrigation scheme takes place, then the Ord River will be close to fully allocated.21 The current environmental flows, including annual floods, are essential to maintain the health and integrity of the local environment, including the internationally recognised Ramsar wetlands, located in the lower reaches of the Ord. Storing water in northern Australia Virtually all rivers in northern Australia are intermittent. This means that they do not flow in the dry season. Water supplies in northern rivers vary greatly depending on the season and from year to year. Very large amounts of storage are required for proposed water transport schemes, to even out supply, and to guard against multiple years of below-average rain. There are two main options for providing this storage capacity: storing water in aquifers, in a process called ‘managed aquifer recharge’, or constructing dams. Managed aquifer recharge requires the presence of a suitable aquifer in which to store water. The best aquifers can store and move large volumes of water, because increasing the storage volume reduces the costs of recovering the water. However, managed aquifer recharge involves pumping costs to get the water to ground level. Many aquifers in northern Australia are ‘fill and spill’ aquifers. They recharge with the wet season rains, and then release water during the dry season. Fill and spill aquifers have limited storage capacity, because they fill to capacity during the wet season rainfall. This leaves little or no space to capture and store any additional flows. Water from these aquifers allows rivers to continue to flow through the dry season each year. These perennial river systems, which support endemic ecosystems (unique ecosystems found only in that area) and provide tourism and fishing opportunities, also have high spiritual and cultural significance for Indigenous and non-Indigenous people. Water from these aquifers is not generally available for transport elsewhere. In some locations where water resource planning processes are underway, such as the Katherine and Douglas–Daly areas of the Daly region in the Northern Territory, computer modelling of water supplies indicates that current groundwater allocations may be approaching the limit of recoverable extraction.22 The possibility of constructing large dams in northern Australia is limited by geographical and climatic constraints. Ideally, a dam is constructed in a steep valley, where the surrounding hills create a bowl to hold the water. This produces a deep reservoir, which minimises the amount of water lost to evaporation. The landscape across much of the north is gently undulating and at a low elevation. This means that steep valleys are rare, and usually of high ecological and cultural value. The best place to build a dam is usually in the upper reaches of a catchment. However, in northern Australia, unlike the Murray–Darling Basin, most rain falls near the coast and not in river headwaters. Rainfall in the upper catchments across inland northern Australia is generally lower and more sporadic than along the northern coast, and potential losses through evaporation are high.23 There are few opportunities to increase surface water storage in northern Australia, and any existing opportunities have already been identified by state and territory governments. Is moving water from the north to the south possible? When considering any proposals to move water long distances, decision-makers must weigh three key sets of issues: social, economic and environmental. Social considerations include the existing value that water has for local communities and others, the views of landholders who might be affected by construction of infrastructure, the value of the employment that such schemes may create locally, and the longer-term consequences that diverting water might have on future regional development. Economic considerations include the extent of existing infrastructure and construction costs of any required infrastructure, the energy costs of transporting the water, and the comparison of water transport costs with those of other water supply options. Environmental issues vary depending on the location of the water source, the water’s destination, and the mode of water transport used. Any long-distance transport of water could lead to the transfer of exotic species from one place to another. The reduction in available water at the source may affect river flows and wetlands; this could alter the composition and populations of plants and animals, and have a large impact on ecosystems. All methods to transport water also involve the use of energy, and therefore produce greenhouse gases. A range of studies, discussed below, have investigated proposals to transport water from higher to lower rainfall areas. All these studies have concluded that proposals to transport water typically have very high economic, energy, social and environmental costs. Proposals for moving water Proposals to transport water long distances are not new. Since the late 1800s, people have been suggesting ways to move water across Australia. In 1938, Dr John Bradfield, respected engineer and designer of the Sydney Harbour Bridge, presented a plan to the Queensland Government. Bradfield proposed diverting water from northern Queensland coastal rivers across the Great Dividing Range into central Australia. This proposal, known as the Bradfield Scheme, has inspired many other suggestions for redirecting water from the north to the south of Australia (Figure 2). These include transporting floodwater from north-eastern coastal rivers across the Great Dividing Range and into the Murray–Darling Basin, or down the east coast to supplement urban water supplies. Others have suggested that water from the north-west of Australia — such as from Lake Argyle and the Ord River in the East Kimberley — could supply population centres in the south of Western Australia, or be redirected through Lake Eyre to the upper Darling River and then into the Murray–Darling Basin. Figure 2: Map illustrating common proposed routes for pipeline/canal 
Diverting water from the northwest of Australia In 2006, the Western Australian Government made a detailed study of proposals to bring water from the Kimberley to Perth.24 The study examined transporting water by pipeline, canal and ocean transport. The feasibility of these options was compared using the following measures: • how much energy would be required to transport the water • how reliable the water supply would be • what quality of water would be provided, and • the estimated cost. The report concluded that introducing water from the Kimberley into Perth’s water supply would at least double the average household water bill. Water prices for Western Australian metropolitan residences in 2009–10 ranged from 64.3 c/KL to 177.9 c/KL (depending on the volume of water used).25 These costs are considerably less than the cost per KL of any of the transport options described in the report (see Table 1). The report also found that water could be supplied by desalination for less than a quarter of the cost of any of the proposed methods of diversion from the Kimberley (see Table 1). Table 1: Costs and energy requirements of water transport options from the Kimberley to Perth based on 200 GL/year delivery, compared with the cost of water from the Kwinana desalination plant 
Based on ‘Table of comparative issues and values’ Western Australian Department of Premier and Cabinet (2006). Options for bringing water to Perth from the Kimberley; p 10. * Estimate based on supply of 47 GL of water per year from the Kwinana plant, including operating costs. Environmental impacts The study found that there was relatively little information available to estimate the environmental impacts of moving water from the Kimberley to Perth. However, it noted that as well as the impacts of obtaining water from the Kimberley, there would be environmental issues in moving the water to Perth by any of the methods suggested. These include the production of greenhouse gases in the construction, transport and treatment of the water, and the impact of canals or pipelines on the land and local ecosystems. Social impacts Consultation showed that the local community did not want Kimberley water to be seen as a free or wasted resource. The community argued that there should be greater support for development within the region, and a better understanding of the cultural and environmental significance of local water resources for local people. Diverting water from the north-east of Australia The Bradfield Scheme (and variations of the scheme) for the Murray–Darling Basin The original Bradfield Scheme, submitted to the Queensland Government in 1938, proposed that floodwater from the coastal rivers of north Queensland be diverted across the Great Dividing Range and into inland river systems. The scheme aimed to increase the amount of water available to support agriculture and grazing in central Queensland. The original proposal relied on gravity to move water from one catchment to another. More recent surveying indicates that an extensive array of pipelines, pumps and diversion tunnels would be required to achieve this outcome. When the Bradfield Scheme was reviewed in 1947 by WHR Nimmo, Chief Engineer of the Stanley River Works, more information had become available. Bradfield was found to have overestimated the amount of water available from the Tully, Herbert and Burdekin rivers by about 250 per cent. It was also found that water could not be diverted by gravity from the Burdekin catchment to the Flinders catchment.26 In 1982, Cameron McNamara Consultants were commissioned by the Queensland Government to undertake a study that reviewed the feasibility of the Bradfield Scheme. This study found that it would be possible to irrigate around 72 000 ha of land west of the Great Dividing Range, at a cost of more than $3 billion.27 At the 2007 Water Summit, the then Queensland Premier asked whether water could be diverted from rivers in north Queensland to recharge the Murray–Darling Basin. He proposed that this could be done by extending the Bradfield Scheme to divert water into the Warrego River, a tributary of the Darling. The then Northern Australia Land and Water Taskforce met with Queensland Government officials in September 2007 to discuss this proposal and the findings of a preliminary feasibility assessment. The preliminary assessment concluded that while such a scheme may be technically possible, it would not be economically, environmentally or practically feasible. Additionally, the outstanding natural values of the wet tropical region of north Queensland have been recognised in a World Heritage listing, which includes parts of the Tully and Johnstone rivers. Based on this advice, the Taskforce agreed to not consider this proposal further unless it was supported by the Queensland Government. South-East Queensland water grid In 2007, the Queensland Government commissioned a report on a proposal to transport water from the north-east of Australia by diverting water from the Burdekin River to south-east Queensland.28 To estimate the costs and timeline of the proposal, the report looked at similar construction projects and estimates from construction suppliers. The report considered the variability of local ground conditions; the costs of the pipeline crossing roads, railway lines, rivers and creeks; and the need for pumping stations. The final estimate included the cost of providing road access and power to pumping stations, and ongoing operation and maintenance costs. It did not include the cost of water treatment. According to the Queensland Government, sourcing water from the Burdekin River would, at minimum, quadruple south-east Queensland’s residential water bills. Water from the Burdekin would, by 2026, cost $7700 per ML if pumped on a continuous basis, and up to $374 000 per ML if pumped only once in every 50 years. In comparison, providing water through desalination was estimated to cost between $2500 and $3500 per ML. Construction of the pipeline was anticipated to take 6–10 years from design to commissioning. Northern New South Wales Proposals similar to the Bradfield Scheme have also been suggested for the coastal rivers of New South Wales. A review of 22 coastal catchments found that only nine had western boundaries on the Great Dividing Range. Even though diverting some of these nine rivers was technically possible, the cost was too high to justify construction.29 Later, proposals were raised for inland water diversion from the Clarence River. However, none of these proposals for the Clarence River were supported by cost– benefit analyses or environmental and social impact assessments.30 The Clarence River basin is unique in that it lies in a transition zone between temperate and tropical flora. This makes it a region with high biodiversity values. A 1999 Healthy Rivers Commission report argued that any proposal to divert significant quantities of water out of this river basin would pose significant risk to the health of riverine ecosystems, and the activities and values those systems support.31 In 2003, an analysis of 23 options to divert water inland from the Clarence River was undertaken by Hunter Water Australia. The study estimated that the final delivery cost to irrigators for diverted water would range from $163 to $2807 per ML (approximately 10 to 200 times greater than the existing irrigation costs).32 Similarly, a desktop analysis of 40 options to capture and divert water from the Northern Rivers of NSW (including the Clarence River) to north east NSW and south east Queensland was undertaken by the Snowy Mountains Engineering Corporation Australia in 2007. The study estimated that the best value option was to deliver up to 100 000 ML of water per year from the Clarence River, at a delivery cost to users of $1730 per ML. The study also found that a more detailed environmental analysis would be required before any of the options could be progressed.33 Flooding the Lake Eyre Basin Since the late 1800s, there have been calls for various schemes to artificially fill Lake Eyre, in the hope that this would increase local rainfall. The Bureau of Meteorology and CSIRO have carried out statistical analyses and climate modelling to assess the likely impact of large permanent inland water surfaces on Australian rainfall. The study found that ‘there was no evidence that large-scale permanent water surfaces in inland Australia would result in widespread climate amelioration’.34 The Lake Eyre Basin is one of the world’s last unregulated wild river systems. The vegetation of the basin reflects the patterns of arid and semi-arid regions, which rely on variable water flows. Because of this, the basin is an area of high conservation significance. It supports wetlands such as the internationally recognised Coongie Lakes, along with grasslands in the Astrebla Downs National Park and deserts in the Simpson Desert National Park. The combined ecological and economic impacts of flooding Lake Eyre are likely to be significant. Other water diversion schemes Sugarloaf North–South Pipeline The Sugarloaf North–South Pipeline was proposed as part of the Victorian Government’s Our Water, Our Future plan. It involves a 70 km pipeline connecting the Goulburn River, near Yea, to the Sugarloaf Reservoir north-east of Melbourne, to supplement urban water supplies. Upon completion, up to 75 GL of water per year will be delivered to Sugarloaf Reservoir. Construction commenced in 2008, and the first water was delivered to Melbourne in February 2010. On 12 September 2008, the Minister for the Environment, Heritage and the Arts approved the Sugarloaf Pipeline Project subject to a number of strict conditions for the protection of matters of national environmental significance under the Environment Protection and Biodiversity Conservation Act 1999, specifically listed threatened species and ecological communities. The Department of the Environment, Water, Heritage and the Arts is monitoring compliance with these conditions. Transporting water from Tasmania As well as proposals to divert water from northern Australia, suggestions that water could be transported from Tasmania to the mainland have been made. In March 2008, the Council of Australian Governments agreed to extend the CSIRO work on sustainable yields and water availability in the catchments of the Murray-Darling Basin and northern Australia to Tasmania. The Tasmanian Sustainable Yields report, released in January 2010, found that climate change is expected to reduce rainfall and runoff in Tasmania over the next two decades.35 By 2030, the projected impact of climate change on rainfall will be a 3 per cent reduction under a median future climate (ranging from an increase of 1 per cent to a decrease of 7 per cent under wet and dry extremes). The reduction in rainfall is projected to lead to a 5 per cent reduction in runoff under a median climate (ranging from an increase of 1 per cent to a decrease of 10 per cent under wet and dry extremes). This report provides critical information needed to underpin statutory water management planning in Tasmania and will assist in ensuring that any development of Tasmania’s water resources is sustainable. What does all this mean? When it comes to climate and water, Australia is a country of extremes. The challenge we face is to manage our scarce water resources, in our shared interests, over the long term. As water becomes scarcer, it becomes a more valuable and expensive commodity. However, if water prices become high enough to make a long pipeline or canal economically viable, then alternative water supplies such as desalination will also become economically viable. Using the water we have more efficiently, and developing new local water supply sources — particularly those that rely less on rainfall — are considered much better options than transporting water across the country. Although water transport projects may be technically possible, every study so far has found that such projects would have high energy, economic, social and environmental costs. Building and maintaining the infrastructure required to move water is expensive, and a large amount of energy is required to pump water over long distances. Water transport projects also remove water from ecosystems at the source; combined with moving water through the landscape, this has a substantial impact on the environment. The social costs are high for those communities who will lose water, and whose wellbeing depends on environmental health at the water source. Water for the Future Managing our water supplies will remain a challenging task and a topic of much debate in Australia. It is important to ‘think big’ about the possibilities. But, it is also important to evaluate the economic, environmental and social costs of each option carefully. With our diverse range of water supply options, and careful consideration of how we use our water, we can ensure a sustainable and secure water supply for the future. Water for the Future is an Australian Government initiative to prepare Australia for a future with less water. Water for the Future involves: • taking action on climate change • using water wisely • securing water supplies, and • supporting healthy rivers. The initiative includes investing in updated irrigation systems, helping households to install rainwater tanks and greywater treatment systems, supporting development of alternative water supplies, and buying water to return to the environment. Alternatives to diverting water — what else can we do? A secure, reliable water supply is vital for Australia’s social, economic and environmental wellbeing. Dam yields have declined over the past decade, and there is a risk of further declines in rainfall and runoff as a result of climate change. We must find new sources of water for urban supplies that are less dependent on climate. To improve the reliability of water supplies, governments are implementing planning practices that consider the merits of the full range of supply and demand options. These include water recycling, desalination, urban rain and stormwater harvesting, and improving water use efficiency. Improving rural water use efficiency The irrigation sector is the biggest user of water in Australia. It accounts for around two-thirds of all water use nationwide. Approximately 65 per cent of this irrigated agriculture takes place within the Murray– Darling Basin.36 Irrigated agriculture provides a wealth of food and fibre, which generates billions of dollars in export income and provides fresh food for Australian households. Despite the economic importance of irrigated agriculture, the expected future drop in water supplies due to climate change requires greater water use efficiency for crops. The amount of irrigation water lost to leakage and evaporation each year is estimated to be about the same as that consumed by all of our major capital cities. Under the Water for the Future Initiative the Australian Government is modernising Australian irrigation. The primary focus is on the Murray-Darling Basin, where irrigation activities are concentrated. As part of Water for the Future, the Australian Government has committed $5.8 billion to increase water use efficiency in rural Australia through the Sustainable Rural Water Use and Infrastructure program. This program’s key rural water projects will support sustainable irrigation communities, and save water by upgrading outdated and leaky irrigation systems. The water savings generated by this investment will be used to address overallocation, help restore river health, and help irrigators meet the challenge of declining water availability. Improving urban water use efficiency Significant amounts of water can be saved by improving household water use efficiency. The Water Efficiency Labelling and Standards (WELS) scheme is a national program established by the Australian Government in partnership with all state and territory governments. The scheme commenced mid-2005 and became mandatory for new products from 1 July 2006. The purpose of the WELS scheme is to: • conserve water supplies by reducing water consumption • provide purchasers with information on water use and water-saving products, and • promote the adoption of efficient and effective water use and watersaving technologies. The WELS scheme requires products such as washing machines, dishwashers, taps, showers, flow controllers, toilets and urinals to be registered and labelled according to their water efficiency. This allows consumers to make informed decisions about the water efficiency of the products they purchase, reduce their water consumption and save money on water bills. The scheme also enables industry to showcase their most water-efficient products. Approximately 10 600 product models are registered under the scheme. Work is underway to introduce minimum water efficiency standards, and to examine the scheme’s potential to include additional products such as instantaneous gas hot water services, combination washerdryers, evaporative air conditioners, domestic irrigation flow controllers and hot water re-circulators. A 2008 study into the cost effectiveness of the WELS scheme estimated that by 2021, Australians could save up to $1 billion on their water and energy bills by choosing WELS water-efficient products.37 This translates into potential Australia-wide water savings of approximately 800 GL (more water than is in Sydney Harbour). Improved water efficiency will also reduce the energy used by products that heat water. This will result in fewer greenhouse gas emissions. From 2005 to 2021, the WELS scheme is projected to save more than nine million megawatt-hours of energy and about six million tonnes of greenhouse gas emissions. Reduce consumption Piping water does not address all the challenges of living in a relatively dry country. Reducing our water use has an important role in ensuring secure water supplies. Urban water users can reduce their consumption by adopting water-saving devices and changing their patterns of water use. Many people, especially those who rent, may not be aware of how much water they are using in their household.38 What can I do to reduce my household water use? • Observe water restrictions. • Check for leaks. • Buy dishwashers, washing machines and plumbing products that have a high star rating under the WELS scheme. • Take shorter showers and install a water-efficient shower head. A normal shower uses 15–25 L of water every minute, but a water-efficient shower uses only around seven L. A five-star WELS-rated shower head can save an average household more than $100 each year on water and energy bills and cut greenhouse gas emissions by up to one tonne per year. • Install a dual flush toilet that can save you 50 per cent of water on each flush. • Install aerators on taps. • Consider using greywater from the laundry on the garden. • Consider investing in a front-loading washing machine. It may cost more initially, but will use less water and detergent. Wash clothes in cold water. • Install a dripper system and a tap timer, and check hoses and taps for leaks. • Use mulch on gardens to prevent water loss. • Choose a drought-resistant lawn, or consider alternatives such as artificial turf. • Install a rain water tank. Recycled water and greywater Recycled (or reclaimed) water refers to sewage that has been treated by a series of processes, such as micro-filtration, reverse osmosis, oxidation and ultraviolet disinfection, to create clean water and even drinking water. Many countries with climates similar to ours and with limited fresh water supplies use recycled water. In Australia, recycled water has been used for decades for watering parks and ovals, and for industrial use and irrigation.39 In some areas, communities are discussing the possibility of using recycled water for drinking water, usually described as ‘planned indirect potable reuse’. This means that recycled water is returned to the local water source (reservoir, river or aquifer), where it is stored and then collected and treated in the same way as existing water supplies. Recycled water can be less dependent on rainfall than many water supplies. It uses less energy than desalination and reduces the amount of nutrients (such as phosphorus and nitrogen), sediments, and contaminants discharged to the environment. The Australian Guidelines for Water Recycling provide a national framework for managing human and environmental health risks, and guidance on how recycling can be done safely and sustainably. While the introduction of recycled water into drinking water supplies is a decision for state governments, water managers and communities, recycled water for drinking needs to meet the requirements of the Australian Drinking Water Guidelines, which are designed to protect public health. Another option for water reuse is using greywater — water from the kitchen, laundry and bathroom (but not the toilet) — on gardens. Greywater reuse can occur at the household level, allowing all Australians to contribute to managing limited water resources.40 Desalination plants Many states are investing in desalination plants, because they can provide long-term water security.41 Desalination plants remove salt and impurities from seawater, and treat the water so it meets drinking quality standards. The most common method used for desalination is reverse osmosis. This involves forcing water through a membrane under high pressure. The advantage of desalination is that water is available even in times of low rainfall. However, desalination is expensive, uses large amounts of energy and produces brine (water with a high concentration of salt) as a byproduct. References 1 Living with Drought (www.bom.gov.au/climate) 2 Bureau of Meteorology average annual, seasonal and monthly rainfall and rainfall variability (www.bom.gov.au/climate/averages) 3 Australian Water Association (2007), Water in Australia Facts & Figures, Myths & Ideas (www.awa.asn.au) 4 CSIRO Murray–Darling Basin Sustainable Yields Project (www.csiro.au/partnerships/SYP.html) 5 Australian Water Association (2007), Water in Australia Facts & Figures, Myths & Ideas (www.awa.asn.au) 6 CSIRO Northern Australia Sustainable Yields Project (www.csiro.au/partnerships/SYP.html) 7 Government of Western Australia (2003), Securing our water future: a state water strategy for Western Australia (www.water.wa.gov.au/PublicationStore/first/41070.pdf) 8 Ghassemi F and White I (2007), Inter-basin Water Transfer: Case Studies from Australia, United States, Canada, China and India. International Hydrology Series, Cambridge University Press, Cambridge. 9 Snowy Mountains Hydro Electric Authority (1993), Background information Snowy Mountains Scheme. Snowy Mountains Hydro Electric Authority, Cooma. 10 Pendlebury P, Erskine W, Lake S, Brown P, Pulsford I, Banks J, Nixon J (1996), Expert Reference Panel Environmental Flow Assessment of the Snowy River below Jindabyne Dam. Unpublished report to the Snowy Genoa Catchment Management Committee, Cooma. 11 Snowy Water Inquiry Outcomes Implementation Deed. 3 June 2002, Section 7. 12 WA Department of Premier and Cabinet (2006), Options for bringing water to Perth from the Kimberley (www.water.wa.gov.au/PublicationStore/first/64772.pdf) 13 WA Department of Premier and Cabinet (2006), Options for bringing water to Perth from the Kimberley (www.water.wa.gov.au/PublicationStore/first/64772.pdf) 14–16 CSIRO Northern Australia Sustainable Yields Project (www.csiro.au/partnerships/SYP.html) 17 Woinarski J, Mackey B, Nix H and Traill B (2007), The Nature of Northern Australia: Natural values, ecological processes and future prospects. ANU E Press, Canberra (epress.anu.edu.au) 18 CSIRO Northern Australia Sustainable Yields Project (www.csiro.au/partnerships/SYP.html) 19 National Land and Water Resources Audit, Australian Catchment, River and Estuary Assessment (2002) (www.anra.gov.au/topics/coasts) 20 Australian Fisheries Management Authority (www.afma.gov.au/fisheries) 21 WA Department of Water (2006), Ord River Water Management Plan, Water Resource Allocation and Planning Series Report No. WRAP 15. WA Department of Water, Perth. (www.water.wa.gov.au/PublicationStore/first/70582.pdf) 22–23 CSIRO Northern Australia Sustainable Yields Project (www.csiro.au/partnerships/SYP.html) 24 WA Department of Premier and Cabinet (2006), Options for bringing water to Perth from the Kimberley (www.water.wa.gov.au/PublicationStore/first/64772.pdf) 25 Water Corporation 2009-2010 Rates and Charges — Metropolitan Residential. (http://www.watercorporation.com.au/A/accounts_rates_metro_res.cfm) 26 Ghassemi F and White I (2007), Inter-Basin Water Transfer: Case Studies from Australia, United States, Canada, China and India. International Hydrology Series, Cambridge University Press, Cambridge 27 Ghassemi F and White I (2007), Inter-Basin Water Transfer: Case Studies from Australia, United States, Canada, China and India. International Hydrology Series, Cambridge University Press, Cambridge; cost estimated in 2002 prices 28 Qld Department of Natural Resources (2007), Direct Connection Pipeline: Burdekin to South- East Queensland (www.derm.qld.gov.au/water) 29–30 Ghassemi F and White I (2007), Inter-Basin Water Transfer: Case Studies from Australia, United States, Canada, China and India. International Hydrology Series, Cambridge University Press, Cambridge 31 Ghassemi F and White I (2007), Inter-Basin Water Transfer: Case Studies from Australia, United States, Canada, China and India. International Hydrology Series, Cambridge University Press, Cambridge 32 Hunter Water Australia (2003), Financial Appraisal of Water Options. Newcastle, Australia. In: Farmhand Foundation 2004, Talking Water: An Australian Guidebook for the 21st Century (http://www.farmhand.org.au/press.html) 33Snowy Mountains Engineering Corporation Australia (2007), Integrated water supply options for north east New South Wales and south east Queensland. (http://www.nwc.gov.au/www/html/562-integrated-water-supply-options-for-north-east-nsw-and-south-east-qld.asp) 34 Hope PK, Nicholls N, and McGregor JL (2004), The rainfall response to permanent inland water in Australia. Australian Meteorological Magazine, 53:4, 251–262. 35 CSIRO Tasmania Sustainable Yields Project (www.csiro.au/partnerships/SYP.html) 36 Australian Bureau of Statistics (2007), Water and the Murray-Darling Basin — A Statistical Profile, 2000–01 to 2005–06 (Cat. No. 4610.0.55.007) (www.abs.gov.au) 37 Chong J, Kazaglis A and Giurco D (2008), Cost effectiveness analysis of WELS — the Water Efficiency Labelling and Standards Scheme. Prepared for the Australian Government Department of the Environment, Water, Heritage and the Arts by the Institute for Sustainable Futures, University of Technology, Sydney (www.waterrating.gov.au/publications/) 38 Marsden J (2006), Securing Australia’s Water Supplies: Opportunities and Impediments. A discussion paper prepared for the Department of Prime Minister and Cabinet (www.environment.gov.au/water/publications) 39 National Water Commission (2007), Recycled Water fact sheet (www.nwc.gov.au) 40 National Water Commission (2008), Requirements for the installation of rainwater and greywater systems in Australia, Waterlines report No 10 — November 2008 (www.nwc.gov.au) 41 For example, see Australian Water Association desalination fact sheet (www.awa.asn.au) or the National Urban Water Desalination Plan fact sheet (www.environment.gov.au/water) Glossary Aquifer A land formation that holds groundwater Ecosystem A group of plants and animals interacting with each other and the environment in which they live Endemic Native and unique to a place, not occurring elsewhere Estuary The part of the mouth or lower course of a river in which the current meets the sea tides and is subject to their effects Evaporation Changing from a liquid into a vapour Evapotranspiration Evaporation of water from the Earth’s surfaces, including soil and water sources, and also from vegetation transpiration Groundwater Water beneath the ground surface Groundwater recharge A hydrologic (water circulation) process in which water moves downward from surface water to groundwater Headwaters The source of a river or stream Hydro-electric Electricity generated from the movement of water Managed aquifer recharge The purposeful recharge of water to aquifers (underground reservoirs) under controlled conditions for subsequent recovery or environmental benefit Monsoon depression An area of low pressure circulation (such as a cyclone) in certain regions that results in high levels of rainfall Over-allocated For water, the planned removal of more water from a river system than is available Sustainable yield The level of water extraction from a particular system which, if exceeded, would compromise key environmental assets or ecosystem functions and the productive base of the resource Surface water Water above the ground surface MORE INFORMATION More information about Water for the Future visit www.environment.gov.au/water To order printed copies of this booklet call 1800 218 478 or email: Waterinformation@environment.gov.au Directory: system -> files -> resources resources -> Living Sustainably resources -> Interim recovery plan 2004-2009 Julie Patten1 resources -> Issues Paper for the Grey Nurse Shark Carcharias taurus resources -> Farming and nationally protected grasslands and woodlands of the Victorian volcanic plain resources -> About nailsma ltd resources -> Our heritage provides an enduring golden thread that binds our diverse past with our life today and the stories of tomorrow resources -> Appendix 1 ssd publications and presentations for 2007–08 Journal papers resources -> Water down under resources -> Desktop review – Impact of bushfires on water quality resources -> Review of existing cultural and social initiatives Download 132.93 Kb. 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