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WATER DOWN UNDER

Understanding and Managing Australia’s Great Artesian Basin

© Commonwealth of Australia 2011

This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced by any process without prior written permission from the Commonwealth. Requests and inquiries concerning reproduction and rights should be addressed to the Public Affairs, Department of Sustainability, Environment, Water, Population and Communities GPO Box 787 Canberra ACT 2610. Email: public.affairs@environment.gov.au

Readers are advised photos in this publication may contain images of deceased Aboriginal and Torres Strait Islander people.

ISBN: 978-1-921733-19-2

Text: Carol Booth, Wendy Tubman

PDF Design: Fivefold Creative

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 New South Wales, Queensland, South Australia, and Northern Territory governments.

While reasonable efforts have been made to ensure that the contents of this publication are factually correct, the above parties do not accept responsibility for any errors, 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.’

For the purpose of citation, the PDF version of Water Down Under available from http://www.environment.gov.au/water/publications/agriculture/great-artesian-basin-managing.html is to be considered the official version.

Introduction


The Great Artesian Basin (GAB) is one of the world’s largest groundwater resources. It lies under 22% of Australia, stretching from the wet tropics to outback deserts and vast pastoral areas.

A relatively unsung hero, the GAB has sustained Aboriginal people for thousands of years and now supports a wide range of communities, enterprises and industries. It is truly a resource of national importance.

Like many of Australia’s natural resources, the GAB faces many challenges. New, rapidly evolving industries now compete with traditional pastoral and agricultural users for a share of GAB water.

Management of the GAB is complex and requires a great deal of cooperation between five governments, hundreds of communities and the many industries that rely on its waters.

‘Water Down Under’ is a timely introduction to the many features, wonders and uses of the Great Artesian Basin – how it functions, how its use has changed over time and how it must be protected and managed into the future.

Jeff Austin

Chair

Great Artesian Basin Coordinating Committee (GABCC)

Connections


On a snowy day in New York, a shivering commuter slips on a pair of mittens. The wool of her mittens was shorn from a sheep that drinks from a trough near Marree in South Australia. The water in the trough has emerged under its own pressure, from a bore reaching down 1000 metres into the Great Artesian Basin, and after an underground journey lasting many hundreds of thousands of years.

The water first seeped into the earth during a downpour on the Great Dividing Range in eastern Australia. Some of the rain re-emerged in a nearby spring, where herds of giant wombat-like diprotodons drank.

Some of it journeys on still, destined to meet the sun again in a million or so years in mound springs near Lake Eyre, where the local Aboriginal people teach their children how the springs are linked to their Dreaming.

In such ways the mysterious flows of the Great Artesian Basin connect us across time, distance and cultures.

It is sometimes tempting to envisage Australia’s Great Artesian Basin as an enormous underground lake, separate from ‘real’ life above until tapped for productive use.

But it is not a lake at all; it is solid rock, with water stored in the pores between the coarse grains of sand in vast sandstone sheets. And the Basin’s water is connected to aboveground lifecycles, received as rain, and emerging in springs, streams and bores.

The springs are inextricably woven into stories and histories of Aboriginal people. They sustained early European exploration and settlement where permanent water was scarce. With the drilling of bores, artesian waters now sustain people, towns and industries across almost a quarter of the country, in Queensland, New South Wales, South Australia and the Northern Territory.

Wise management of this extraordinary resource is fundamental to the well-being – and future – of Australia and its people.

The Basin is much more than a reservoir for people to water the arid, sparsely populated land above. It is home to some of the oldest continuous cultures on Earth and attracts thousands of visitors every year. Its waters contribute to the billions of dollars worth of industry that operate within the Basin, and support unique plants and animals. The Basin’s waters offer considerable potential for increased levels and greater diversity of production, and ways of facing future challenges such as climate variability and low carbon energy sources.

Time, Rocks and Water


Turn on a tap in Birdsville or Bollon or Andamooka, and you can drink water that fell as rain 1 to 2 million years ago and percolated into a giant underground basin crafted by nature 100 to 200 million years ago. Geology and meteorology have endowed Australia with one of the world’s largest freshwater reservoirs – holding enough to cover the Earth’s landmass with half a metre of water.

Sometime during the Triassic age, over 200 million years ago, when Australia was joined with Africa, South America, Antarctica and New Zealand as part of Gondwana, a shallow ocean covered the low-lying northeast quarter of Australia. Fine-grained mud and silt settled out and, over time and under pressure, formed an impermeable layer of rock. When the ocean retreated, great rivers washed sand from eroding ranges over the area. That sand packed down to form a vast sheet of sandstone atop the bedrock of mudstone and siltstone.

Over tens of million of years, as ice ages came and went, as oceans advanced and retreated, and as rain eroded mountains, the various natural forces laid down more rock, sandwiching porous and permeable sandstone sheets between impermeable mudstone and siltstone.

The Basin took its current shape, sloping down to its southwestern margins, after the collision of tectonic plates lifted its eastern edges, and other parts gradually subsided.

Most of the water entering the aquifers of the Great Artesian Basin falls as rain or leaks down from riverbeds on the western slopes of the Great Dividing Range. It joins a grand procession, trickling south, southwest and west through the sandstone down the incline towards central Australia. In the north, the flows are to the north and northwest. Some water also percolates into the system in central Australia from rain and surface flow.

Confined under pressure by the mudstone and siltstone layers above and below, the water wends through microscopic gaps between coarse rock grains and fractures in the rock, drawn onward by the combined influence of gravity and pressure at a rate of one to five metres a year.

Water emerges naturally from the Basin through faults or vents into springs or shallow watertables or leaks slowly through confining layers to the surface of the Basin. Most springs and leakages occur on the southern and western edges of the Basin where some aquifers come closer to the surface and confining layers are thinner. Springs also occur on the eastern edge of the Basin not far from where the water entered the system. Some water emerges into creeks and rivers.

But for the past century, some of the underground water has taken a shortcut to the surface – through bores drilled into the sandstone aquifers.



The Basin undoubtedly deserves the ‘Great’ of its name, for it is the largest artesian basin in the world, and one of the largest reservoirs of fresh water. It holds 65,000

million megalitres (65,000,000,000,000,000 litres).

Water quality and temperature

map showing the extent of the great artesian basin


Geographical extent of the GAB

Dimensions


Basin depth: from <100 m at the edges to 3000 m at the thickest

Area: 1.7 million km2, 1300 km at its widest, about 22% of Australia

Total volume of stored water: 65,000 million mega litres (65,000 km3)

Age of water: up to 2 million years

Maximum pressure: 1300 kilopascals

Water temperature: average 30–50° C, max 100° C at the surface; 130°+ C at depth

Average groundwater flow rate: 1–5 metres per year

diagram - operation of an artesian basin - described in following text

An aquifer is a wet underground layer of water-bearing permeable rock or unconsolidated materials (gravel, sand, or silt) in which groundwater can flow.

The oldest, lowest layers of the Basin actually sit in a few different basins separated by rock ridges, but the upper layers of the Basin are continuous.

Water Quality and Temperature


Fed by rainfall, much of the Basin’s waters are of appropriate quality for most uses, including drinking. But minerals absorbed during the journey underground mean that water quality varies. High sodium levels in water from some aquifers make it unsuitable for irrigation, or too salty for human consumption. The water is often quite alkaline, and some contains high levels of fluoride.

Water temperatures also vary, from 30°C in shallow aquifers to more than 100°C in deep aquifers. The water is warmed by heat produced in the Earth’s crust by uranium and thorium and by past volcanic activity.



water flowing from a bore in the outback - the water is coloured blue-green due to minerals in the water

Photo courtesy of GABCC

Natural Flows


In four shallow springs on a spinifex plain in Queensland’s dry centre, male Red-finned Blue-eyes flash their scarlet-tipped fins to attract a mate. Just three centimetres long, this tiniest of Australian freshwater fish is so distinctive that it is the only member of its own sub-family.

And numbering only 3000 or so, its future is uncertain. The Blue-Eyes are one of many unique kinds of life populating the springs of the Great Artesian Basin. As enduring wet places within a dry landscape, the springs support a wide range of both plants and animals found nowhere else. Research into these places continues to discover species never before described.



photo of the three centimetre long red-finned blue-eye, as its name suggests this tiny fish has a blue eye and red tips on its fins and tail. the remainder of its body is blue-green silver

Photo courtesy Adam Kerezsy

The Red-finned Blue-eye (Scaturiginichthys vermeilipinnis) lives in springs with a combined area of less than 0.3 hectares, part of the Edgbaston Springs complex. Many springs at this location dried up due to bore development, but introduced mosquito fish are now regarded as the main threat to the blue-eye’s survival. The Edgbaston Springs have two other unique fish and many rare and geographically restricted kinds of invertebrates and plants, which are now protected in a conservation reserve.

Water flows from the Basin through thousands of mainly small spring vents and soaks located in more than 600 artesian springs and spring groups, mostly around the southern, western and northern margins in South Australia and Queensland. Their flows are generally low, from less than 1 litre to about 150 litres per second.

The springs are genuine oases since much of the Basin area averages less than 200 mm of rain a year. Evaporation from waterbodies can reach 4000 mm a year.

a mound spring (foreground) in an arid part of the south australian part of the gab

Blanche Cup mound spring, South Australia Photo Courtesy of GABCC

The biological communities that depend on springs are links to times long past, when central Australia was lush with wetlands. The great drying of inland Australia over millions of years has left many water-dependent creatures surviving only in springs. Most other natural waterbodies in arid parts of the Basin are dry for part of the year. The isolation of these communities has led to the development of species found nowhere else.

Springs along the eastern and northern edges of the Basin occur where aquifers overflow with recent rainfall. These springs also sustain diverse and unique plants and animals. A large array of spiders and insect species inhabit the spring wetlands (known as boggomosses) near the Dawson River in Queensland.

a recharge spring among lush rainforest in the tropical north queensland part of the gab

GAB recharge site Elliot Falls, Jardine River National Park, Cape York Peninsula, Qld Photo courtesy Glenn Walker

Artesian springs on Cape York Peninsula have high flows that support lush rainforest. They also contribute substantially to the baseflow of some rivers. Other springs discharge through the sea bed in the Gulf of Carpentaria.

Basin waters also flow into at least 80 other waterways – augmenting baseflows that help sustain them during times of low rainfall.

Life underground


Scientists continue to discover life deep underground. Many kinds of stygofauna are microscopic. Some species can live in boiling and corrosive water as found in parts of the GAB. The task of identifying the thousands of microscopic species in artesian water has barely begun.

stygofauna in a gab spring

Photo courtesy of Sarah Moles

diagram showing the extent of the great artesian basin, state boundaries, flow direction recharge areas and spring groups as detailed in the section

There are a dozen main groups of discharge and recharge springs containing thousands of individual springs and seeps

Natural discharges


Water naturally emerges from the Basin:

Through discharge springs – at the western and southern margins, where aquifers come close to the surface, and elsewhere, where aquifers meet vents or faults.

Through recharge springs – along the eastern margins, where aquifers overflow with water that recently entered the system.

Into waterways in some parts of the Basin; the extent of this flow is poorly understood.

Via shallow watertables – as much as half of the natural water loss from the Basin occurs by leakage through thin confining rock close to the surface.

People and the Basin


For traditional owners of the Basin area, the springs across the vast arid interior were often the only assured source of water, and prime sites for hunting. They remain precious cultural and sacred sites – integral to ceremonies and stories, permeated with the histories of their ancestors, to maintain the cultural power of many springs.

We are in the middle of kwarye (water) it is all around us, we have to look after this place.

Mr Bingy Lowe, Elder, Southern Arrernte people

Artefacts and oral histories show that springs were often places for making and collecting tools and plant products that could be traded with other tribes along trade routes following the chain of springs. Some such sites are 12,000–20,000 years old. The ancient tools, rock art, burial places and scarred trees found around springs are protected by law.

Forging beyond early settlements, searching for a mythical inland sea, explorers wrote of finding marshes, salty rivers, springs, areas of mysteriously verdant vegetation, wetlands, reed beds and salt mounds. For years they were oblivious to signs that ‘the sea’ was indeed there – but down under.

Some of these signs, the springs, enabled the journeys of early European explorers such as Stuart, Warburton and Babbage. They were sites of pastoral settlement and travel routes for camel trains carrying essential supplies and wool for early settlers. The overland telegraph and the Ghan railway followed the line of GAB springs through South Australia.

‘Barren scrub’ was explorer John Oxley’s description of reed beds he struggled through for weeks in 1818 in northwest NSW. Unbeknownst to him, he was crossing the Great Artesian Basin, in the area now known as the Macquarie Marshes. Oxley eventually gave up on this journey of ‘disappointment and desolation’.

In 1878, sixty years after Oxley’s ‘disappointment’, the clues finally fell into place. The first bore was drilled into the Basin at Killara Station, in north-western New South Wales, finding water at 53 metres. The first substantial flows came from holes drilled in 1886–87, at Thurulgoonia Station and Barcaldine in Queensland. The 210 metre Barcaldine bore gushed more than 700,000 litres a day, making news around the world and triggering a bore drilling boom and pastoral development. By 1900, despite the huge expense and uncertainty of success, 524 bores had been sunk.

From Bamaga in the far north, south to Dubbo in central NSW, and from Toowoomba in the east to Coober Pedy in the west, water from the Great Artesian Basin contributes to the lives of more than 180,000 people and 7,600 enterprises.

Basin water is used in households in more than 120 towns and settlements and on hundreds of properties. The pastoral industry has long been the largest user of GAB water, but it is also used in petroleum, mining, tourism and other industries. Total production in the GAB area is worth billions of dollars per year.

The precise degree to which the waters of the GAB contribute to Australia’s rural economy is difficult to know, but it is clear from the historical pattern of development of the basin area, and the dependence of some industries on groundwater supplies, that it is crucial to economic development.


Dean Ah Chee, of the Southern Arrernte people, describes how important the mound springs in Witjira National Park (on the western edge of the Simpson Desert) are to his people:

[They] are universal to our Tjukurba...

Tjukurba is not just a story, nor a myth, for Tjukurba is more than just ‘Dreaming’, it contains our spiritual connection, our traditional lore, our culture, our heritage and the stories, songs and dances associated with the land. It contains the reasons for how and why things such as water, fire and the landscape exist.

dean ah chee on his traditional land

Dean Ah Chee of the Lower Southern Arrentre people on traditional lands Photo courtesy of Dean Ah Chee

Production uses of Basin water


Water from the Basin is the lifeblood of many rural communities and agricultural, mining and tourism businesses.

Traditionally, pastoralism has used the greatest proportion of Basin water, however this decreased under the various bore rehabilitation and bore drain replacement programs. Pastoral water use will continue to decrease as remaining bores are capped and more bore drains are replaced with pipes and troughs.

The mining of copper, uranium, coal, bauxite and opals depends on a reliable supply of artesian water from the Basin. The extraction of oil and gas from the Basin results in the simultaneous extraction of substantial amounts of artesian water as a by product. For example, coal seam gas extraction is a rapidly expanding industry, and likely to use large amounts of artesian water for the life of those projects. Once regarded as a waste, this ‘associated’ water is now seen as a resource with potentially economically valuable uses.

Tourist attractions and developments across the Basin rely on artesian water. In some areas, artesian water is used in mineral spas and tourists are attracted by the cultural and natural history of springs that are developed as visitor sites.



The Flows Slow


[‘It is flowing, ever flowing,’ crowed bush poet Banjo Paterson in 1896 in his ‘Song of the Artesian Water’. The tremendously and endlessly gushing waters of early bores even convinced some that the supply was ‘inexhaustible’.

black and white photo of a sheep in the desert drinking from a flowing man-made artesian bore

Historic image - Sheep at Cambridge Downs Station Qld circa 1894 Image: John Oxley Library 109158

In a way they were right. The Great Artesian Basin will not run dry, 120 years of exploitation having used up less than 0.1 per cent of the water stored. But what declines is water pressure. When water flows from a bore, there is less pressure available to push water out of the aquifer downstream.

Even before the start of the twentieth century, only a decade into the bore water boom, declining flows dashed hopes of an inexhaustible supply. In 1912, the first of many interstate conferences was called to consider remedies.

Despite the continued drilling of new bores, flows from artesian bores peaked at more than 3,000 megalitres a day in 1915. As the number of bores grew to more than 4,700, artesian pressure began to fall and the total flow from bores declined to about 1,500 megalitres a day. Pressure in some bores fell by as much as 80 metres and a third stopped flowing altogether. As artesian pressure fell, so did the amount of water flowing from the aquifers below. Expensive pumping was needed to extract water from bores that became sub-artesian.



line graph showing rate of discharge from flowing artesian bores, total number of flowing artesian bores drilled and flowing artesian bores from 1880 to 2000 - discharge rates commence at zero and climbed rapidly to a peak of approximately 3200ml per day in the early 1900s then decreased over the next 90 years to approximately 1500ml. the total number of bores drilled in the period is approximately 5000, with about 3,200 that are remain flowing

GAB bore discharge and bores drilled summary

Located at the far end of the aquifers, the desert springs were particularly vulnerable to declining pressure. In addition to dwindling flows, many springs were damaged by excavation, trampling by stock and even by tourists. Exotic invaders such as goats, camels, pigs, mosquito fish and various weeds all degraded the areas around springs.

Technology and the materials available for the construction of bores, prior to the middle of the 20th century, limited the life of bores, resulting in bore failure and leakage. Early bores were uncontrolled, flowing freely into open drains where more than 95 per cent of the water was wasted by seeping into the soil and evaporating in the hot, dry air.hey]
But it’s hark! The whistle’s blowing with a wild, exultant blast,

And the boys are madly cheering, for they’ve struck the flow at last:

And it’s rushing up the tubing from four thousand feet below,

Till it spouts above the casing in a million-gallon flow.

And it’s down, deeper down-

Oh, it comes from deeper down:

It is flowing, ever flowing, in a free, unstinted measure

From the silent hidden places where the old earth hides her treasure-

Where the old earth hides her treasures deeper down.

Song of the Artesian Water” by Banjo Patterson, published in The Bulletin, 12 December 1896.



Improving Basin Management


Loss of pressure and declining flows sparked calls for state governments to control bore drilling. In 1910, the Queensland Government assumed ownership of Basin water and required landholders to obtain bore licences. In 1912, the New South Wales Government introduced licensing and construction standards for bores over 30m deep in the western division, and this was amended in 1966 to enable all groundwater to be vested in the Crown. South Australia passed similar legislation in 1976 and also moved to regulate bore construction.

As technology improved, laws were passed requiring flow-control mechanisms and distribution in pipes instead of open drains. Standards were set to prevent bore erosion and leaking.

From 1952, State governments also set up schemes to rehabilitate free-flowing bores and replace drains with pipes. By 1999, more than 600 bores had been capped. But, with over 3,000 uncontrolled bores and 34,000 kilometres of open drains, much work remained.

When wetter is not better


Permanent water was once sparse across most of the Basin, but the development of the pastoral industry saw the construction of thousands of dams, bores and windmills, and thousands of kilometres of bore drains. Weeds established along bore drains and millions of once-arid hectares became accessible to feral animals that compete with native animals for food and habitat, or prey directly on them.

There are now few places more than six kilometres from a waterpoint. Those native animals adapted to a waterless existence have fared poorly. But the water has been a boon for other wildlife – seed-eating birds, for example, which need to drink. Some species of kangaroo have also benefited and expanded their range.

The bore rehabilitation and bore drain replacement programs of the past few decades have provided opportunities to manage this situation, restore some of the natural balance and protect wildlife in the arid lands.

The Great Artesian Basin Strategic Management Plan


Community concern about the waste of water, falling artesian pressures and related natural resource problems such as erosion around bores and weed invasion, led to the development of a Strategic Management Plan (SMP) for the Basin. It was completed and signed by Ministers in 2000. While town and rural supply had been the traditional uses of Basin water in the 20th century, the expansion of mining and other industries required a new, wider focus.

The SMP envisioned a Basin-wide approach based on cooperation and coordination, underpinned by a better understanding of the Basin and improved technologies, materials and industry practices.

The SMP heralded a new era of looking at the Basin and how it is used. Decades of capping and piping had already changed many landholders’ attitudes – and behaviours – as to how much better the resource could be managed. Outback tourism was leading to a growing appreciation of the Basin’s Indigenous and non-indigenous cultural values, and environmental values. In turn, this was raising awareness of the Basin in the wider community. Interest from research organisations was adding to the scientific understanding of the Basin, while new materials and technologies held – and continue to hold - the promise of better monitoring, new infrastructure and even new industries.

gab-capped-bore.jpg

Landholder and rehabilitated (capped and piped) bore Photo courtesy of GABCC

At the same time, State and Territory governments moved to amend legislation and establish new frameworks to allocate and manage Basin waters. States coordinated with each other and statutory water sharing plans for the GAB were finalised in Queensland, New South Wales and South Australia between 2006-2009. Springs are protected in these plans by caps on the amount of water that can be allocated and by set-back distances for licence approvals. The Plans also enable water trading and harmonise and coordinate cross-border arrangements. The Northern Territory has commenced development of a plan.

Springs that depend on the natural discharge of GAB water are now recognised as a threatened ecological community and listed under Commonwealth legislation as a matter of national environmental significance. A recovery plan for their on-going protection and management is now in place.

In addition to the springs protection provisions in the GAB water sharing plans, some springs are now also protected in conservation reserves. Research to share and better understand the values and needs of the springs is also underway, including an extensive GAB bibliography, database and mapping of more than 4,000 spring vents. In addition, there are many on-ground projects to control the weeds and feral animals that have degraded springs. Some of these projects are benefiting from partnerships with the traditional owners.

The SMP also captured the significance of resource management partnerships in the Basin and the collaboration between resource management groups in protecting cultural heritage and environmental values. For example, partnerships are being built between GAB water managers and community-based natural resource management groups, which have a key role in land management activities in the GAB.

Great Artesian Basin Sustainability Initiative


In parallel with the targets of the SMP, the Australian Government initiated the Great Artesian Basin Sustainability Initiative (GABSI) in 1999. This program helps landholders rehabilitate bores and replace bore drains with piped systems.

By 2009, water savings from GABSI and earlier initiatives had topped 299,000 megalitres a year. These capping and piping programs have conserved water and brought other public and private benefits. More flows are reaching springs; the removal of drains is reducing erosion, weeds and feral animals; pastoralists can better manage grazing pressure; and some of the water saved can be used for economic benefit. The many advantages for graziers, including financial gains, have convinced most that closed water delivery systems are the best option.



Our operating costs have been reduced by around $20 000 and that’s a conservative estimate. Even though it was expensive to rehabilitate the bore because of its depth, we’ve really benefited from reduced maintenance and labour costs, and it’s easier to manage our stock.

Ian Hall, grazier, Mulianna (near Quilpie, Queensland)



Cooperative management


The SMP, GABSI and coordinated state water plans are good examples of the increasingly cooperative management of the Basin. So too is the Great Artesian Basin Coordinating Committee which works collaboratively to ensure consistency across State borders, the involvement of stakeholders in all Basin states, the encouragement of targeted research activities, and to ensure Ministers are informed of emerging issues.

The 2004 National Water Initiative provides the over-arching framework for cooperative management of the Basin waters for economic, social and environmental benefits. Among other things, it has guided the establishment of water markets to achieve the most profitable and judicious use of artesian water, and more transparent and comprehensive water planning.

Basin land and water management is undergoing continuous reform through numerous public and private initiatives, including projects by natural resource management groups, increased protection for springs, and improved industry practices.

These reforms are being supported by solid research and shared knowledge. A GAB Resource Study was published in 1998, and updated in 2010. It provides a snapshot of management approaches and technical, ecological, social and economic conditions of the Basin. Since then, a number of significant research projects have, and are continuing to be, funded by the Commonwealth, Basin States and NRM groups. The GABCC released a research and development prospectus for the GAB in 2008.

An independent report into how the GAB is managed across state borders was prepared by Sinclair Knight Merz in 2004. A mid-term review of GABSI Phase 2 was undertaken in 2008 and a review of GABSI infrastructure was completed in 2010. The GAB SMP was also updated in 2008 to provide a sharper focus for its implementation and to reflect the significant technical, social and political changes since 2000.

The Australian Government, in collaboration with the States, is establishing a consistent Basin-wide hydrological monitoring network and funding a major water resource assessment of the GAB. This is due for completion in 2012.



Ongoing research, improved technology – such as telemetry to monitor bores remotely – and new materials for pipes and bores, will ensure past achievements are built upon and more sophisticated management continues into the future.

Protecting artesian springs


Improvement of spring flows, now a higher priority, is being achieved through bore capping and limits to water extraction. Recovery of endangered ecological communities at springs is guided by a federal recovery plan. Some springs are protected in conservation reserves and others are being rehabilitated through the efforts of government, community groups and individuals. Six spring researcher forums have also been held since 2000 to share technical knowledge.

Who Does What


Within a framework of cooperative management:

State and Territory governments manage their respective parts of the Basin under their own laws and receive advice from state GAB advisory groups. Water plans, developed in consultation with the community, set water entitlements and protect flows to springs and waterways. Under GABSI, the State and Australian Governments and landholders agreed to work cooperatively and to invest significant public and private funds to repair uncontrolled artesian GAB bores and replace open bore drains with piped water reticulation systems. State level GAB advisory groups report to their respective Ministers on groundwater matters and guide the roll-out of GABSI piping and capping programs within their state.

The Australian Government facilitates the cooperative management of water resources through intergovernmental agreements, and contributes half the public funding for GABSI. Federal environment laws apply when actions may affect nationally listed threatened species or ecological communities such as the community dependent on GAB natural discharge springs.

The Great Artesian Basin Coordinating Committee, with representatives from federal, state and territory governments, community stakeholders and water users, facilitates cooperative and collaborative management of the Basin. It provides policy advice, monitors progress, identifies research needs, and liaises with other groups.

Natural Resource Management Regional bodies, of which there are 19 across the Basin, address some of the broader natural resource issues – such as weeds and pest animals – arising from the use and management of Basin waters.

Water users and land managers contribute to Basin management by participating in GABSI, adopting new technologies, improving land management and industry practices, and participating in water planning.
Under GABSI, the federal and state governments subsidise up to 80 per cent of the cost of bore capping and 40-80 per cent of the cost of replacing bore drains with pipes.

Benefits of capping & piping for graziers:


Reduces maintenance and labour costs

Improves stock and grazing control

Reduces degradation around drains

Facilitates control of feral animals

Improves water quality and pressure

Increases the reliability of supply



Capping and piping progress to mid – 2010:





Bores controlled

Bore drains removed (km)

Water saved / year (GL)

Pre-GABSI

641

3,234

126

GABSI to 30 June 2010

517

16,437

173

Total

1,158

19,671

299

Estimated still to go

537

7,314

-

A Strong Future


Since concerns about the state of the Great Artesian Basin were first raised more than a century ago, considerable reform has been achieved. In the face of rising demands for water in a more variable climate, satisfaction of ecological, economic and social goals will be met through strong, collaborative partnerships.

There is already concerted action to protect springs and the ecological communities that depend on them. Recognition is growing that Basin water must be used in ways that maintains and enhances biodiversity and reverses land degradation. There is also a move towards more active participation, especially with Indigenous Australians seeking to strengthen their connections to springs and traditional lands.

Opportunity exists in a number of areas for improved harmonisation of state water sharing plans in the ‘next generation’ planning cycle. This will further promote consistent management outcomes for the GAB. Legislation is also progressively being amended to ensure adequate regulation of the impacts of emerging industries.

Consistent Basin-wide monitoring is progressively expanding, and new pressures on water resources in the area of the GAB are seeing increasing research to ensure decisions about the allocation and management of the GAB are supported by best available science.

Encouragingly, the third phase of GABSI involves an increased level of funding and has an emphasis on works that will lead to water pressure recovery at identified high value springs. Research into infrastructure failure associated with interaquifer leakage is helping define the extent of the problem and will inform management responses.

Increased pressure on surface water resources due to climate change, coupled with new demands from emerging industries, will increase demands on the Basin. Prudent management needs to ensure future generations have multiple choices in how it can be used.



three people stand on a viewing platform looking at a discharge spring in the great artesian basin

Viewing platform protects vegetation from trampling

Future uses


Uses for the hot artesian water are being explored – possibilities include heating buildings, bathing, aquaculture, air-conditioning, refrigeration, and electric power generation.

Australia’s only geothermal power plant, at Birdsville in far west Queensland, uses hot water from the Basin. Interest in this form of low-emissions power generation is increasing.

Coal seam and shale gas extraction are developing as major industries at various locations in the GAB.

There is also interest in using the Basin to store carbon dioxide emitted from power stations. But there are still major logistical problems associated with such sequestration, and long-term impacts and costs are, as yet, uncertain.



gab-geothermal.jpg

Geothermal energy production at Innamincka, SA

Climate change and the Basin


Climate change is predicted to increase already high evaporation rates from bore ponds, drains, and springs, and a more variable climate will increase demands on Basin water. While changes in rainfall resulting from climate change will affect how much water enters the Basin, artesian flows are extremely slow – at only 1 – 5 m per year – and so the impacts of any changes are unlikely to be noticeable within normal planning horizons for the GAB.

Geothermal energy from deep within the Basin has the potential to reduce our dependence on fossil fuels and reduce greenhouse gas emissions.

Ongoing cooperative management by governments, industries and communities, based on improved information, effective legislation, advanced technologies and strong partnerships will ensure sustainable use of the treasure that is Australia’s Great Artesian Basin.

Timeline


Pre-European settlement – Springs used by Indigenous people for physical, spiritual and

cultural needs for 10,000 – 30,000 years


1878 First artesian bore drilled

1880s Governments investigate the extent and potential of the Basin

1910/1912 Bore licensing laws passed in Qld & NSW

1912–1928 Interstate conferences on diminishing flows

1954 Inter-jurisdictional report on Basin management completed

1954–1980s States regulate water distribution systems

1952–1999 Bore rehabilitation under state schemes

1987 Technical groups formed to advise governments on Basin policy

1997 Brisbane Forum on GAB Management

1997–2002 GAB Consultative Council

1998 GAB resource study produced

1999 Great Artesian Basin Sustainability Initiative initiated (GABSI)

2000 GAB Strategic Management Plan adopted

2004 National Water Initiative agreement

2004 GAB Coordinating Committee established

2004 SKM report on GAB management issues across state borders

2000–2006 Six Springs Researcher Forums held

2006 GABCC jointly convenes a regional natural resource management forum with

Lake Eyre Basin and Murray-Darling Community Advisory committees



2006–2009 Water sharing plans for Qld, NSW and SA finalised

2008 GAB Strategic Management Plan updated

2009 Number of bores controlled under GABSI reaches 483

2009 GABSI infrastructure review conducted

2010 Release of the Commonwealth springs recovery plan

2010 Commenced GAB Water Resource Assessment
Directory: system -> files -> resources -> 6405b0fb-1956-4790-9ca4-b138ed810717 -> files
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 -> Desktop review – Impact of bushfires on water quality
resources -> Review of existing cultural and social initiatives
resources -> The Australian Collaborative Rangelands Information System (acris): Reporting Change in the Rangelands


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