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The Great Artesian Basin

Water in the dry interiorTeacher guide and lesson plans

Lower secondary

The Great Artesian Basin: Water in the dry interior Teacher guide and lesson plans – Lower secondary

ISBN: 978-1-74200-126-5

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Acknowledgments:

Front- and back-cover, and banner photographs, and page 4 background photograph © Commonwealth of Australia.

Front cover: photograph by Angus Emmott, above (left), below (centre left); photograph by Cameron Slatyer, above (right); photograph by Gunther E Schmida, below (far left); photograph by Allan Fox, below (centre right); photograph by Neil Eigeland, below (far right).

Back cover: photograph by Angus Emmott, above, below (far right); courtesy Murray-Darling Basin Authority, photograph by John Kruger, below (centre left); photograph by Yvonne Webster, below (centre).

Background (page 4): photograph by Yvonne Webster.

2 | The Great Artesian Basin Water in the dry interior

CONTENTSBig Idea: How do we ensure that Australia’s water use is sustainable?

4

The Great Artesian Basin – Overview

5

Investigation 1 How important is artesian water in Australia?

9

Lesson 1.1 The importance of springs

13

Lesson 1.2 Mapping the Great Artesian Basin

20

Lesson 1.3 The value of artesian water – a local study

28

Investigation 2 How does the Great Artesian Basin work?

33

Lesson 2.1 How the Great Artesian Basin works

36

Lesson 2.2 Investigating artesian pressure

46

Investigation 3 What impacts have humans had on the Great Artesian Basin?

49

Lesson 3.1 What’s happened to the Great Artesian Basin?

52

Investigation 4 What can be done to address the current issues facing the Great Artesian Basin?

61

Lesson 4.1 The race to cap and pipe

63

Investigation 5 What can I do to ensure our water is used more sustainably?

68

Lesson 5.1 Groundwater and my household

71

Lesson 5.2 Does water divining work?

74

Glossary

80


BIG IDEA

How do we ensure that Australia’s water use is sustainable?

In a dry arid country such as Australia, the Great Artesian Basin is a precious

resource. In a time of projected reduced annual rainfall and frequent drought

what do we need to do to ensure this water resource is secured for future

generations and the diversity of our communities and ecosystems are

sustained?

Teacher guide and lesson plan | 5


Overview


The Great Artesian Basin is a vast underground water reservoir lying beneath approximately one-fifth of the Australian continent. It consists of a system of sedimentary layers which were laid down over millions of years and stores about 65,000 million megalitres of water, 130,000 times the capacity of Sydney Harbour. For millennia, scattered artesian springs fed by water from the Basin have sustained ecosystems in arid Australia and shaped the trade routes used by the Indigenous people. The discovery that the Basin could be tapped by bores has allowed much of arid

Australia to become productive grazing land. To ensure that its resources are available for future generations, it is vital that the Great Artesian Basin is managed in a sustainable manner.


At a glance

Guiding investigations Lessons Outcomes

1 How important is artesian water in Australia?

1.1 The importance of springs

Students recognise the environmental significance of artesian springs and identify their cultural significance to Indigenous Australians.

1.2 Mapping the Great Artesian Basin

Students identify the extent of the Great Artesian Basin and recognise its significance in settlement patterns.

1.3 The value of artesian water – a local study

Students carry out research and produce a poster or presentation to communicate the importance of artesian water to a community in arid Australia.

2 How does the Great Artesian Basin work?

2.1 How the Great Artesian Basin works

Students describe the structure and functioning of the Great Artesian Basin and explain how it can operate as a sustainable water resource.

2.2 Investigating artesian pressure

Students identify the source of artesian pressure and explain its relationship to well-drilling by operating a model.

3 What impacts have humans had on the Great Artesian Basin?

3.1 What’s happened to the Great Artesian Basin?

Students investigate human impacts on the Great Artesian Basin and identify issues affecting sustainability of land and water use.

3.2 Case study – Elizabeth Springs

Students recognise the threats to groundwater dependent ecosystems associated with a mound spring.

4 What can be done to address the current issues facing the Great Artesian Basin?

4.1 The race to cap and pipe

Students analyse strategies used to tackle the issues confronting the Great Artesian Basin and identify how they contribute to sustainability.

5 What can I do to ensure our water is used more sustainably?

5.1 Groundwater and my household

Students investigate the extent and nature of groundwater resources in the local area and make recommendations about drilling a well to extract water.

5.2 Does water divining work?

Students perform a double-blind investigation to test whether water divining works


Australian Curriculum Links

Science – Year 7

Science Understanding Science as a Human Endeavour

Science Inquiry Skills

Biological sciences

There are differences within and between groups of organisms; classification helps organise this diversity

Interactions between organisms can be described in terms of food chains and food webs; human activity can affect these interactions

Chemical sciences

Mixtures, including solutions, contain a combination of pure substances that can be separated using a range of techniques

Earth and space sciences

Some of Earth’s resources are renewable, but others are non-renewable

Water is an important resource that cycles through the environment

Nature and development of science

Scientific knowledge changes as new evidence becomes available, and some scientific discoveries have significantly changed people’s understanding of the world

Science knowledge can develop through collaboration and connecting ideas across the disciplines of science

Use and influence of science

Science and technology contribute to finding solutions to a range of contemporary issues; these solutions may impact on other areas of society and involve ethical considerations

Science understanding influences the development of practices in areas of human activity such as industry, agriculture and marine and terrestrial resource management

Planning and conducting

Collaboratively and individually plan and conduct a range of investigation types, including fieldwork and experiments, ensuring safety and ethical guidelines are followed

In fair tests, measure and control variables, and select equipment to collect data with accuracy appropriate to the task

Processing and analysing data and information

Construct and use a range of representations, including graphs, keys and models to represent and analyse patterns or relationships, including using digital technologies as appropriate

Summarise data, from students’ own investigations and secondary sources, and use scientific understanding to identify relationships and draw conclusions

Evaluating

Reflect on the method used to investigate a question or solve a problem, including evaluating the quality of the data collected, and identify improvements to the method

Use scientific knowledge and findings from investigations to evaluate claims

Communicating

Communicate ideas, findings and solutions to problems using scientific language and representations using digital technologies as appropriate


Geography (from Shape of the Australian Curriculum: Geography)

Geographical knowledge and understanding

Year 7

Weather and water

the hydrologic cycle describes the movement of water between the atmosphere, land and oceans

weather can be a hazard, but the risks can be reduced through human adjustment to the conditions presented

water is a difficult resource to manage because it is integrated into environmental systems in complex ways, can be highly variable over time and across space, and has many competing uses

Geographical inquiry and skills

Developing a geographical question

observation can lead to questions for investigation

Planning a geographical inquiry

some geographical features can be explained by cause and effect relationships with other places

Collection, evaluating and managing information

primary and secondary data must be evaluated for accuracy and bias before being analysed

census data can be used to describe the growth, movement and characteristics of the populations of places

information collected in a survey should be evaluated for reliability

Making sense of the information

mapping the spatial distribution of a characteristic such as rainfall, can be a first step in developing an understanding of that characteristic and suggesting possible causal relationships

Communicating

each type of communication has conventions that should usually be followed for communication to be effective

the climate of place can be represented by a graph of average monthly temperature and precipitation

Planning and implementing actions

finding a way of resolving a problem depends on an understanding of the causes of that problem

Reflecting on the investigation

each investigation should be evaluated for what has been learned about the topic investigated and what has been learned about the process of investigation


INVESTIGATION 1

How important is artesian water in Australia?

IntroductionFor at least a million years, springs fed by artesian water have sustained isolated and unique ecosystems in arid areas. Indigenous people in these areas depended on springs for water and food, and planned their travel routes around them. They became places of great cultural and spiritual significance. We need to acknowledge that the springs are important and help them to survive as close to their original state as possible.

Artesian springs result when water from a confined aquifer naturally reaches the surface, either because of faulting which fractures overlying aquitards, or because the aquifer is close to the surface at the margins of the basin. Many springs are surrounded by conical mounds up to several metres high consisting of sediments deposited from the artesian water. For this reason, they are often called ‘mound springs’.

Early European settlers found it difficult to extend pastoral activities into central Australia because of the lack of water. The discovery of artesian water allowed expansion into the centre and the establishment of permanent communities. In addition to the pastoral industry, communication, transport, mining and tourism became easier with reliable supplies of water. The Basin needs to be managed sustainably so that those communities and industries can continue.

Much of inland Australia has very low annual rainfall and limited supplies of surface water. Indigenous people had an intimate knowledge of groundwater resources and incorporated artesian springs into their network of trackways. The springs were crucial stepping points in the construction of the Overland Telegraph line in the early 1870s, opening up the first fast communication between Australia and the rest of the world. European settlers understood the importance of these springs, but the existence of a vast underground water resource was not appreciated until it was tapped by an increasing number of wells in the 1880s. Unlike groundwater in most wells, water from these wells flowed freely to the surface under great pressure. This had immense consequences for inland Australia, allowing for the development of agriculture, mining, transport, tourism and the towns which serviced these industries.

Groundwater and surface waterWater on the earth’s surface (surface water) is connected to water beneath the surface. Some water from rainfall, rivers and lakes seeps into the ground and becomes groundwater. In an unconfined aquifer, the water moves downward through pore spaces in the soil and rock until it meets an impervious layer. The pore spaces above the impervious layer become filled with


Source: U

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conomics and S

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is an independent research agency of the Australian G

overnment

water up to a surface known as the water table. Above the water table, the pore spaces are only partly filled with water. As water is added or removed, the water table may move up or down.

An aquifer that has non-porous layers (aquitards) above and below is called a confined aquifer. Water enters a confined aquifer at intake beds, which are higher than the rest of the layer. The water further along the confined aquifer is under pressure due to the weight of the water above it. Consequently, if a bore is drilled into the aquifer, the water may rise above ground level, and is then known as artesian water. The potentiometric surface defines the height to which the artesian water may rise.

All groundwater dissolves minerals from the rock as it passes through an aquifer. The high temperature of much artesian water, and the large distances it travels through the aquifers means it can carry a significant mineral load.

Groundwater

Types of aquifer

Types of aquifers

Teacher guide and lesson plan: Investigation 1 | 11

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Australian Curriculum links

Science – Year 7



Biological sciences

There are differences within and between groups of organisms, classification helps organise the diversity

Interactions between organisms, can be described in terms of food chains and food webs, human activity can affect these interactions





Science knowledge can develop through collaboration and connecting ideas across the disciplines of science



Communicating





Year 7

Weather and water









census data can be used to describe the growth, movement and characteristics of the populations of places



Communicating








Lessons

Lesson 1.1The importance of springs

Outcome

Students recognise the environmental significance of artesian springs and identify their cultural significance to Indigenous Australians.

Background

The Great Artesian Basin is a huge system of water-bearing sedimentary layers (aquifers) confined between impervious layers (aquitards). In places where the aquifers are exposed at the surface, or where faults fracture the aquitards, water leaks out and forms artesian springs. Springs tend to occur in clusters known as spring complexes, and these complexes are often part of a more regional group known as a supergroup.

Before European settlement, the Great Artesian Basin was essentially in balance: the amount of water entering aquifers in the intake regions matched the amount flowing from artesian springs scattered throughout the Basin. These springs flowed continually and were a reliable source of water in times of drought. They supported a variety of wildlife, but because of the poor water quality and sparse food, the surrounding areas were not occupied permanently by Indigenous people. They were important for trade routes and feature in many songlines.

Artesian springs are home to one form of groundwater dependent ecosystem (GDE) – an ecosystem whose composition, structure and function rely on groundwater. Individual spring groups are isolated, like islands in an archipelago and, consequently, many of the species found there are endemic to specific spring groups. These ecosystems are very vulnerable to changes in waterflow, and the maintenance of environmental flows to springs is one of the great challenges of managing the Great Artesian Basin sustainably.

Resources and preparation

Figures, graphs, maps and tables

Figure 1.1 Mound spring at Coward Springs

Figure 1.2 Aboriginal rock art at Carnarvon Gorge

Figure 1.3 Phragmites australis (the common reed)

Figure 1.4 Scaturiginichthys vermeilipinnis (red-finned blue-eye)

Figure 1.5 Chlamydogobius squamigenus (Edgbaston goby)

Figure 1.6 Eriocaulon carsonii (salt pipewort)

Figure 1.7 Eryngium fontanum (blue devil)

Figure 1.8 Sporobolus pamelae (spring dropseed)

Map 1.1 Australia showing artesian springs


Table 1.1 Environmental Protection Biodiversity Conservation Act–listed species associated with Great Artesian Basin discharge spring wetlands ecological community

Video

Water Down Under: The Great Artesian Basin Story (Can be accessed at www.environment. gov.au. Go to ‘Water’, then ‘Publications and resources’, then ‘Water for agriculture publications’.)

References

Connected Water, Groundwater Dependent Ecosystems, www.connectedwater.gov.au/framework/ground_dependant_ecosystems.html

Department of Environment and Resource Management, The State of Queensland 2010, Recovery plan for the community of native species dependent on natural discharge of groundwater from the Great Artesian Basin, www.environment.gov.au/biodiversity/threatened/publications/recovery/pubs/great-artesian-basin-ec.pdf

Department of Sustainability, Environment, Water, Population and Communities, The community of native species dependent on natural discharge of groundwater from the Great Artesian Basin, Threatened species and ecological communities, www.environment.gov.au/cgi-bin/sprat/public/publicshowcommunity.pl?id=26&status=Endangered

National Water Commission: Groundwater Dependent Ecosystems, www.nwc.gov.au/www/html/225-groundwater-dependent-ecosystems.asp


http://www.nwc.gov.au/www/html/225-groundwater-dependent-ecosystems.asp

http://www.nwc.gov.au/www/html/225-groundwater-dependent-ecosystems.asp

http://www.environment.gov.au/cgi-bin/sprat/public/publicshowcommunity.pl?id=26&status=Endangered

http://www.environment.gov.au/cgi-bin/sprat/public/publicshowcommunity.pl?id=26&status=Endangered

http://www.environment.gov.au/biodiversity/threatened/publications/recovery/pubs/great-artesian-basin-ec.pdf



http://www.connectedwater.gov.au/framework/ground_dependant_ecosystems.html

http://www.connectedwater.gov.au/framework/ground_dependant_ecosystems.html

Lesson outline

Show students Figure 1.1. Ask them to compare the artesian springs with the surrounding landscape. Ask students to suggest where the water comes from and outline briefly to the students the nature of artesian springs.

Figure 1.1 Mound spring at Coward Springs

Figure 1.2 Aboriginal rock art at Carnarvon Gorge

Play Chapter 2 of the video, Water Down Under: The Great Artesian Basin Story (preferably from the 4-minute mark). Ask students to summarise why artesian springs have been important to Indigenous communities.

View photos of rock art (such as that shown in Figure 1.2) and artefacts found near artesian springs. Explain that many Aboriginal songs and stories refer to springs and how water can be found. Discuss reasons for the importance of springs in Aboriginal culture.


© Com

monw

ealth of Australia. P

hotograph by Allan

© Com

monw


hotograph by Angus E

mm

ott

Show students Figures 1.3–1.8 of organisms from artesian springs.

Figure 1.3 Phragmites australis (the common reed)

Courtesy M

urray-Darling B

asin Authority

Photograph by John K

ruger

Figure 1.4 Scaturiginichthys vermeilipinnis (red-finned blue-eye)

© Com

monw

ealth of Australia

Photograph by G

unther E S

chmida

Figure 1.5 Chlamydogobius squamigenus (Edgbaston goby)

© Com

monw

ealth of Australia.

Photograph by G

unther E S

chmida

Figure 1.6 Eriocaulon carsonii (salt pipewort)

© Com

monw

ealth of Australia.

Photograph by C

ameron S

latyer

Figure 1.7 Eryngium fontanum (blue devil)

© Com

monw

ealth of Australia.

Photograph by John B

aker

Figure 1.8 Sporobolus pamelae (spring dropseed)

Photograph

© Dr J Travis C

olumbus


Discuss the concept of groundwater dependent ecosystems. Show students Map 1.1. Point out that artesian springs are similar to groups of islands scattered in the ocean (archipelagos). Most species cannot migrate from island to island. Ask students to predict what this would mean for the distribution of plants and animals among artesian springs.



• Describe the limited distribution of some species endemic to artesian springs (see Table 1.1 below – the conservation status comes from the Australian Government’s Environment Protection and Biodiversity Conservation Act). Point out that many such species are endangered. Ask students to debate the importance of saving these species from extinction.

Table 1.1 Environmental Protection Biodiversity Conservation Act–listed species associated with Great Artesian Basin discharge spring wetlands ecological community

Scientific name Common name EPBC Act* Occurrence

Animals

Scaturiginichthys vermeilipinnis

red-finned blue-eye E 1 complex in the Barcaldine, Queensland supergroup

Chlamydogobius micropterus

Elizabeth Springs goby E 1 complex in the Springvale, Queensland supergroup

Chlamydogobius squamigenus

Edgbaston goby V 1 complex in the Barcaldine, Queensland supergroup

Plants

Eriocaulon carsonii salt pipewort E 20 complexes (Queensland, New South Wales, South Australia) plus 2 Qld non-GAB springs

Eryngium fontanum blue devil E 2 complexes in the Barcaldine, Queensland supergroup

Sporobolus pamelae spring dropseed _ 6 complexes; Barcaldine and Eulo, Queensland supergroups

* CE: Critically endangered; E: Endangered; V: Vulnerable

Note: Artesian springs are often found in groups called complexes, and these are usually part of larger regional supergroups.

Adapted from Recovery Plan for the Community of Native Species Dependent on Natural Discharge of Groundwater from the Great Artesian Basin, Department of Environment and Resource Management, The State of Queensland, 2010, page 6, www.environment.gov.au/biodiversity/threatened/publications/recovery/pubs/great-artesian-basin-ec.pdf



: As a summarising activity, ask students to imagine they are representing a community whose local authority area encompasses an artesian spring complex. A planned tourist resort in the district could possibly interfere with the flow of water to the springs, and the community needs to show how important it is to retain them in their natural state. The task is to prepare a list of statements demonstrating the environmental and cultural significance of the springs to the community.

Further student tasks In times of drought, Indigenous people found

refuge in artesian springs. During wetter times, they moved away from the springs and found food across the wider landscape. Explain how this shows that they were managing the environment wisely.

Indigenous people traded ochre, stone implements, bailer shells and pituri. They used trade routes covering thousands of kilometres. Describe how artesian springs would have assisted these trade routes.

Table 1.1 on page 18 shows some plants and fish that are found only in wetlands. It shows how many different places each species is found in. (Individual springs are often found in groups called ‘complexes’. Complexes are often further grouped into ‘supergroups’. Map 1.1 shows the names of the supergroups). Which are more widely spread – the plants or the fish? Suggest some reasons for the difference in spread.

The spring dropseed grass, Sporobolus pamelae in Figure 1.8 is not listed as threatened under the national EPBC Act. Its seeds were used as food by Indigenous people. In which part of the country would this grass have been available? What is its conservation status in that state?

The common reed, Phragmites australis, in Figure 1.3 is widespread in wetlands, including artesian springs. Find out about this plant and how it was used by Indigenous Australians.

Developing vocabulary

Create visual representations of terms that students come across in their inquiry that are unfamiliar and require further explanation. One idea could be to have an individual term (ie ‘aquitard’) on the front of a card and its meaning on the back (ie ‘A layer of rock that does not allow water to pass through’). These cards could hang down from string. Alternatively, individual cards could have both the term and its description on the front and they could be stuck to a wall.

Another option is to provide students in pairs with an unfamiliar word and using a graphic organiser with the word written in the centre, establish a definition, characteristics and a relevant example and non-example. See the model below.

Unfamiliar terms may include underlined glossary terms

Definition Characteristics

Examples Non-examples


Lesson 1.2Mapping the Great Artesian Basin

Outcome

Students identify the extent of the Great Artesian Basin and recognise its significance in settlement patterns.

Background

The Great Artesian Basin underlies 1.7 million square kilometres, or 22 per cent, of the Australian continent. Over this extent, there are large variations in climate and topography, but much of the land is flat and arid. Artesian springs were vital to Indigenous people and early settlers, but the full extent of the Basin was not realised until settlers began to sink bores and succeeded in finding artesian water over a vast area.

Bores are shafts drilled into the earth. The first bore in the Great Artesian Basin was drilled near Bourke, NSW, in 1878. Further discoveries were made in 1886 east of Barcaldine, Qld, and in 1887 near Cunnamulla, Qld. By 1915, more than 1,500 artesian bores had been drilled throughout the Basin and currently there are over 4,500. Vast amounts of previously arid land were opened up to settlement and industry.



Map 1.2 Australia showing rivers

Map 1.3 Australia showing average annual rainfall


Map 1.5 Australia showing Aboriginal trackways

Map 1.6 Australia showing the overland telegraph network

Map 1.7 Australia showing Great Artesian Basin boundary

Reference

The Overland Telegraph, http://www.cultureandrecreation.gov.au/articles/overlandtelegraph

Lesson outline

Provide Map 1.2, and identify the regions where streams are not permanent. Ask why this is so and discuss the implications for Indigenous people and early settlers.


http://www.cultureandrecreation.gov.au/articles/overlandtelegraph

http://www.cultureandrecreation.gov.au/articles/overlandtelegraph

Map 1.2 Australia showing rivers


This work is licensed under a Creative Commons Attribution 3.0 Australia License, http://creativecommons.org/licenses/by/3.0/auMap © Commonwealth of Australia (Geoscience Australia) 2011.


http://creativecommons.org/licenses/by/3.0/au

© Commonwealth of Australia 2011, Bureau of Meteorology

Provide Map 1.3, which shows isohyets for average yearly rainfall. Using Map 1.2 and Map 1.3, find the areas that have both few permanent streams and low rainfall. Again, discuss the implications for inhabitants.

Map 1.3 Australia showing average annual rainfall

Projection: Lambert conformal with standard parallels 10° S, 40° S. Based on a standard 30-year climatology (1961–1990).


Provide Map 1.4. Discuss how knowledge of the artesian springs would have helped the survival of Aboriginal people. Ask how the discovery of artesian springs would have been perceived by early settlers looking for farmland. What issues could have arisen when they began to use the resource?



© Oceania Publications, University of Sydney

Provide Map 1.5. Using Map 1.4 and Map 1.5, discuss the extent to which Aboriginal trade routes could have utilised artesian springs. Do the trade routes seem to converge at spring locations?

Map 1.5 Australia showing Aboriginal trackways


Provide Map 1.6. Using Map 1.4 and Map 1.6, discuss the importance of the Overland Telegraph line, and how its construction in 1870–1872 was helped by the existence of springs. Locate those sections of the line which were obviously dependent on artesian springs and ask students to suggest how water might have been obtained in the other sections.

Map 1.6 Australia showing the overland telegraph network


Provide Map 1.7. Explain that this map shows the area which is underlain by artesian aquifers, so that flowing water can be obtained by drilling. Discuss the ways in which the discovery of an artesian basin of this size would have influenced settlement patterns.

Map 1.7 Australia showing Great Artesian Basin boundary


Ask students to look for patterns in the maps and answer the following questions:

– As an estimate, what fraction of Australia lies over the Great Artesian Basin?

– Which part of the dry interior cannot benefit from Great Artesian Basin artesian water? How does the number of towns in this part of the country compare with the number in the Great Artesian Basin?

– The springs are not scattered uniformly over the Basin. Describe where the main groups are, relative to the Basin boundaries. Suggest why this happens.

– To strike artesian water, wells need to be drilled deeper in the central part of the Basin than near the edges. Suggest a reason for this.

– Artesian water is hot and travels a long way through rock. As it flows, it dissolves minerals from the rock. Water with some dissolved minerals is tolerated by livestock, but it cannot be used to irrigate crops. In general, water in the south-west of the Great Artesian Basin has more dissolved minerals than elsewhere. Predict how this would affect the patterns of agriculture across the Basin. Try to find out how accurate your prediction is. (You can go to the Australian Land Use Map for help http://adl.brs.gov.au/mapserv/landuse/index.cfm.)


Add any unfamiliar terms to the word hanging, word wall or graphic organiser. Ensure students have a good understanding of the underlined glossary terms.




http://adl.brs.gov.au/mapserv/landuse/index.cfm.)

http://adl.brs.gov.au/mapserv/landuse/index.cfm.)

Lesson 1.3The value of artesian water –a local study

Outcome

Students carry out research and produce a poster or presentation to communicate the importance of artesian water to a community in arid Australia.

Background

The drilling of the first artesian bore in 1897 initiated a wave of occupation and settlement into the arid interior. Access to water allowed pastoral industries to expand and towns to develop. Other industries followed. Today, total value of production supported by Great Artesian Basin water is about $3.5 billion per annum.

Access to artesian water has changed the environmental, cultural and social makeup of inland regions. Complex communities have been established, which depend on the resources and income made possible by the Great Artesian Basin. Indigenous cultural traditions have been joined by those of the settlers. Ecosystems which once were adapted to scarce water resources and sparse populations have been modified. To ensure that the diverse values associated with these communities survive, the Basin needs to be managed carefully and sustainably.

Resources and preparation Video


Student worksheet/handoutStudent worksheet 1.1 The value of artesian water – a local study

Student handout 1.2 ‘Song of the artesian water’

References

GAB Consultative Council 1998, Chapter 3: Values associated with the groundwater resource, GAB Resource Study, www.gabcc.org.au/public/content/ViewCategory.aspx?id=41


http://www.gabcc.org.au/public/content/ViewCategory.aspx?id=41


Lesson outline

In this activity, students carry out research to learn about the importance of artesian water to an outback community and incorporate their research into a poster or multimedia presentation. A method is outlined in Student worksheet 1.1.

Suggested local government areas for this activity are: Boulia, Qld (major town, Boulia), Qld; Bulloo, Qld (major town, Thargomindah); Paroo, Qld (major town, Cunnamulla); Coober Pedy, SA (major town, Coober Pedy); Roxby Downs, SA (major town, Roxby Downs); Bourke, NSW (major town, Bourke); Brewarrina, NSW (major town, Brewarrina).

A good way to introduce the lesson would be to show Chapter 4 of the video Water Down Under: The Great Artesian Basin Story. Alternatively, read Banjo Paterson’s poem ‘Song of the artesian water’ on Student handout 1.2.

Developing vocabularyAdd any unfamiliar terms to the word hanging, word wall or graphic organiser.




Student worksheet 1.1

The value of artesian water – a local study

The task: You are required to produce a poster or a presentation showing how important artesian water is to a local community.

Suggested steps

Your teacher will help you select a town from an arid area in the Great Artesian Basin. Visit the local government website http://australia. gov.au/topics/government-and-parliament/ local-government to find the website of the local government authority. From this, gather facts about the locality. Look for information about climate, landscape and industries as well as photographs of the local area.

Local information on climate can be obtained from Climate Data Online http://www.bom.gov.au/%20climate/data Summarise the climate and environmental conditions for the area – rainfall, temperatures, evaporation, riverflow etc.

Make a list of the different types of water users in the region. Your list should include traditional owners, ecological communities and towns as well as industries such as agriculture, mining, tourism etc. You can find these from the local government website above and census data. Census data for the local area can be found in ‘Community profiles’ at the Australian Bureau of Statistics www.censusdata.abs.gov.au/ABSNavigation/prenav/ProductSelect . If your locality is in Queensland, Appendix 1 of the GAB Hydrogeological Framework Report will help: www.derm.qld.gov.au/wrp/pdf/gab/gab - hydrogeological-framework-report.pdf.

Visit the website of endangered spring communities to locate important springs in the area http://www.environment.gov.au/cgi-bin/sprat/public/publicshowcommunity.pl?id=26&status%20=Endangered. If these springs are protected in a reserve or national park, you may be able to find more information about them.

Find out whether there are any mines in this area by visiting the Australian Mines Atlas www.australianminesatlas.gov.au. If so, identify a mine near the town and try to find out whether it makes use of artesian water.

Visit the Australian Land Use Map to find out what agricultural industries exist in the region http://adl.brs.gov.au/mapserv/landuse/index.cfm . What water resources are used by these industries?

Carry out a search at Australia.com to find out about tourist attractions in the area www. australia.com. Do they depend on artesian bores or springs?

Try to identify what each user needs water for, and how much it depends on artesian water.

Design a poster or presentation to tell outsiders how crucial artesian water is to the community you have chosen. Mention important aspects of the local culture, economy and environment. Make sure to point out how the Great Artesian Basin is vital to them.

32 | Water in the dry interior The Great Artesian Basin

http://adl.brs.gov.au/mapserv/landuse/index.cfm

http://www.environment.gov.au/cgi-bin/sprat/public/publicshowcommunity.pl?id=26&status%20=Endangered



http://www.censusdata.abs.gov.au/ABSNavigation/prenav/ProductSelect

http://www.censusdata.abs.gov.au/ABSNavigation/prenav/ProductSelect

http://www.bom.gov.au/%20climate/data

Student handout 1.2

‘Song of the artesian water’

Now the stock have started dying, for the Lord has sent a drought,

But we’re sick of prayers and Providence – we’re going to do without,

With the derricks up above us and the solid earth below,

We are waiting at the lever for the word to let her go.

Sinking down, deeper down,

Oh, we’ll sink it deeper down:

As the drill is plugging downward at a thousand feet of level,

If the Lord won’t send us water, oh, we’ll get it from the devil;

Yes, we’ll get it from the devil deeper down.

Now, our engine’s built in Glasgow by a very canny Scot,

And he marked it twenty horse-power, but he don’t know what is what.

When Canadian Bill is firing with the sun-dried gidgee logs,

She can equal thirty horses and a score or so of dogs.


Oh, we’re going deeper down:

If we fail to get the water, then it’s ruin to the squatter,

For the drought is on the station and the weather’s growing hotter,

But we’re bound to get the water deeper down.

But the shaft has started caving and the sinking’s very slow,

And the yellow rods are bending in the water down below,

And the tubes are always jamming, and they can’t be made to shift

Till we nearly burst the engine with a forty horse-power lift.



Though the shaft is always caving, and the tubes are always jamming,

Yet we’ll fight our way to water while the stubborn drill is ramming –

While the stubborn drill is ramming deeper down.


Student handout 1.2

‘Song of the artesian water’

But there’s no artesian water, though we’ve passed three thousand feet,

And the contract price is growing, and the boss is nearly beat.

But it must be down beneath us, and it’s down we’ve got to go,

Though she’s bumping on the solid rock four thousand feet below.



And it’s time they heard us knocking on the roof of Satan’s dwellin’,

But we’ll get artesian water if we cave the roof of hell in –

Oh we’ll get artesian water deeper down.

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.

And it’s clear away the timber, and it’s let the water run:

How it glimmers in the shadow, how it flashes in the sun!

By the silent bells of timber, by the miles of blazing plain

It is bringing hope and comfort to the thirsty land again.

Flowing down, further down;

It is flowing deeper down

To the tortured thirsty cattle, bringing gladness in its going;

Through the droughty days of summer it is flowing, ever flowing –

It is flowing, ever flowing, further down.

Banjo Paterson

Song of the Artesian Water (1896)by Banjo Paterson


INVESTIGATION 2

How does the Great Artesian Basin work?

OverviewThe Great Artesian Basin is a vast underground water reservoir lying beneath one-fifth of the Australian continent. It consists of a system of sedimentary layers which were laid down over millions of years. Water can flow through the permeable layers ( aquifers ), remaining confined by impermeable layers ( aquitards ) until it escapes through springs or bores . There is continual replenishment of water at the intake beds on the edges of the basin, where the permeable layers are exposed to the surface. The sustainability of the system depends on matching water extraction to water intake.

Artesian water is found within a layer of porous rock called an aquifer. The water remains confined by the aquitards, above and below. The aquifer is recharged by rainfall and surface water, which enters intake beds near the edge of the basin.

The aquifer slopes down away from the intake areas, and the water in the lower parts of the aquifer is under pressure from the weight of the water above. When the aquifer is tapped by a bore, the pressure causes the water to rise and flow freely to the surface. The level to which artesian water will rise over an area is known as the potentiometric surface . The maximum height of the potentiometric surface in the Great Artesian Basin is 130 metres above ground level. Refer to Figure 2.1 on page 40. As more wells have been drilled into the aquifers of the Great Artesian Basin, the pressure has dropped. About one-third of the wells no longer flow freely and require pumping. The reduction in pressure is also felt as a decrease in flow at artesian springs.



Science – Year 7




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Evaluating



Communicating





Year 7

Weather and water













Lessons

Lesson 2.1How the Great Artesian Basin works

Outcome

Students describe the structure and functioning of the Great Artesian Basin and explain how it can operate as a sustainable water resource.

Background

The following extract is from the Queensland Government’s Hydrogeological Framework Report for the Great Artesian Basin Water Resource Plan Area, 2005.

The GAB is one of the largest artesian groundwater basins in the world. It underlies approximately one-fifth

of Australia and extends beneath arid and semi-arid regions of Queensland, New South Wales, South

Australia and the Northern Territory, stretching from east of the Great Dividing Range to the Lake Eyre

depression. The Basin has an estimated total water storage of 65 000 million megalitres.

The GAB was formed between 100 and 250 million years ago, and consists of alternating layers of water-

bearing (permeable) sandstone aquifers and non-water-bearing (impermeable) siltstones and mudstones.

The thickness of this sequence varies from less than 100 m on the Basin extremities to over 3000 m in the

deeper parts of the Basin. Individual bore depths vary up to 2000 m with the average being 500 m.

The aquifers are recharged by infiltration of rainfall, and leakage from streams, into outcropping sandstone

mainly on the eastern margins of the Basin along the Great Dividing Range. Groundwater flows naturally,

because of gravity, from these recharge areas toward springs in the west and southwest. In the north, it

flows to the north and northwest. Groundwater moves slowly through the GAB, at about 1–5 m per year. In

some parts, the water is two million years old.

[...]

Many artesian bores initially flowed at rates of over 3000 megalitres per year (ML/a), but pressure and bore

and spring discharge rates have declined, while the number of bores has increased. Water users realised as

long ago as 1891 that their bore flow rates were falling indicating a fall in artesian pressure. Many artesian

bores have flows of between 3 and 2000 ML/a (GABCC, 1998), and some have ceased to flow.

Use of the extract from the Queensland Government’s Hydrogeological Framework Report on the Great Artesian Basin Water Resource Plan Area (2005)

was approved by the Department of Environment and Resource Management Queensland, 2011




Figure 2.1 Generalised cross-section of the Great Artesian Basin

Map 2.1 The Great Artesian Basin

Video

Water Down under: The Great Artesian Basin Story (Can be accessed at www.environment.gov.au. Go to ‘Water’, then ‘Publications and resources’, then ‘Water for agriculture publications’.)

Materials

Samples of sandstone, shale, mudstone, siltstone; hand lenses; eyedroppers; water in containers

Student worksheet/handouts

Student handout 2.1 Geological history of the Great Artesian Basin

Student handout 2.2 Some facts about the Great Artesian Basin

Student handout 2.3 Flow of water in the Great Artesian Basin in the early 21st century

Student worksheet 2.4 Flow of water in the Great Artesian Basin – three scenarios


http://www.environment.gov.au/

Lesson outline

Ask students to describe their mental picture of underground water. Some will probably have the concept of underground lakes or rivers. Discuss this picture and any others that arise, and look for characteristics that could be used to test them. For example, water from underground lakes would not flow spontaneously to the surface.

Distribute the rock samples, hand lenses, eyedroppers and water. Ask students to examine the rocks carefully with the hand lens and describe any differences they can see. Then ask students to test each sample so that it shows a flat, horizontal surface, place one drop of water onto this surface and observe carefully. Introduce the terms ‘permeable’ and ‘impermeable’ and discuss the following:

– Which rocks are permeable and which are impermeable?

– What is it about permeable rocks that allow water to flow through them?

– Could anything happen to impermeable rocks to allow them to carry water?

Show the first four minutes of Chapter 2 of the Water Down Under video and provide Student handout 2.1. Discuss the following:

– There are layers of permeable rock interbedded with impermeable rock in the Great Artesian Basin. How were they formed? How does this arrangement help the transport of water?

– What is an aquifer? What properties should a rock have if it is to be an aquifer?

– Where are the main intake beds for the Great Artesian Basin? How are they related to the aquifers?

– Provide Student handout 2.2. The Great Artesian Basin holds about 65,000 million megalitres of water. How many litres is this? How many gigalitres? An Olympic swimming pool holds at least 2.5 megalitres of water; how many such pools could be filled by all the water in the Great Artesian Basin?

Show students Map 2.1 and discuss the following:

– In which direction(s) does water flow in the Great Artesian Basin? How is this flow related to springs? How would the springs located near intake areas differ from those in arid areas?

– Water flowing out of some springs in the south-west of the Basin has been in the aquifer for about 2 million years. Use the scale on the map to estimate the distance it has travelled, then calculate how far the water travels each year.


Map 2.1 The Great Artesian Basin


Show students Figure 2.1 and discuss the following:

– Why is the water in artesian aquifers under pressure?

– What is the potentiometric surface? How can it be used to predict whether a bore will be sub-artesian or artesian?

– Describe three different circumstances in which water from an artesian aquifer can flow to the surface.

– Some people believe that the Great Artesian Basin contains a gigantic underground lake. How could they be convinced that this idea

is incorrect? (Note to teachers: water from an underground lake would need to be pumped out. This is not the case with artesian water.)

Distribute Student handout 2.3, which contains some hypothetical figures of distribution of water in the Basin. These figures could represent roughly the distribution in the early 21st century.

Ask students to transfer these figures to the first diagram in Student worksheet 2.4 and have them work out whether the waterflow is in balance under these conditions. Discuss the implications of the fact that the waterflow is not in balance.

Figure 2.1 Generalised cross-section of the Great Artesian Basin

Use of the generalised cross-section of the Great Artesian Basin was approved by the Department of Environment and Resource Management, Queensland, 2011


Finally, ask students to complete the second and third diagrams in Student worksheet 2.4 and answer the questions.

– In both cases, the recharge at intake beds would be 1,000,000 megalitres per year, and for the Basin to be in balance, total outflows must be the same. The leakage to the sea can be regarded as constant, at 10,000 megalitres per year in both cases.

– For the second diagram (pre-European settlement), the flow through bores will be zero. The discharge from springs can be taken as 200,000 megalitres per year (about four times the present rate). Students need to calculate the figure for upward leakage that would result in balanced waterflow.

– For the third diagram, the sustainable flow from bores has been estimated at 450,000 megalitres per year. The total figure for upward leakage and discharge at the springs must be calculated to result in a balanced flow. Students have no way of calculating separate values for each of these, so a range of values is possible. They should realise that each figure will be less than it was 250 years ago, but greater than it is under the present unbalanced conditions.


Create visual representations of terms that students come across in their inquiry that are unfamiliar and require further explanation. One idea could be to have an individual term (i.e. ‘aquitard’) on the front of a card and its meaning on the back (i.e. ‘A layer of rock that does not allow water to pass through’). These cards could hang down from string. Alternatively, individual cards could have both the term and its description on the front and they could be stuck to a wall.


Unfamiliar terms may include the underlined glossary items.




Student handout 2.1

Geological history of the Great Artesian Basin

66 million years ago

Period Geological events Type of rock deposited

Cretaceous

Uplift of Great Dividing Range exposes intake beds

Sea retreats; deposition in lakes and rivers

Shallow sea returns over most of basin

sandstones

mudstones (impervious)144 million years ago

Jurassic

Antarctica and Australia begin to separate

Highlands eroded; sand, gravel and clays deposited by rivers

Sandstones interbedded with mudstone


Triassic

Uplift of basin marginsMostly impermeable base rocks


Permian

Australia and Antarctica begin separating from Gondwana

Australian landmass part of Gondwana

Note: The arrows indicate that the erosion of the highlands and deposition of gravel and clays by rivers extended over the whole Jurassic Period. This is in contrast to other events in the sequence, which had limited timespans (eg, the uplift of the basin margins was confined to late in the Triassic Period).


Student handout 2.2

Some facts about the Great Artesian Basin

Area 1.7 million square kilometres (one-fifth of the continent)

Maximum depth 3,000 metres

Volume of water stored 65,000 million megalitres

Age of water Up to 2 million years

Rainfall recharge 1 million megalitres per year

Maximum pressure 1,300 kilopascals

Temperature of water Average 30–50 degrees Celsius; maximum 100 degrees Celsius

Average groundwater velocity 1–5 metres per yearUse of the extract from the Queensland Government’s Hydrogeological Framework report on the Great Artesian Basin Water Resource Plan Area (2005) was approved by the Department of Environment and Resource Management, Queensland, 2011


Student handout 2.3

Flow of water in the Great Artesian Basin in the early 21st century

Total volume of water in the Great Artesian Basin 65,000,000,000 megalitres

Recharge at intake beds 1,000,000 megalitres per year

Upward leakage (to water table and soil) 400,000 megalitres per year

Discharge through bores 550,000 megalitres per year

Discharge at springs 50,000 megalitres per year

Leakage to sea (in the Gulf of Carpentaria) 10,000 megalitres per yearFigures interpolated from Review of Recharge Mechanisms for the Great Artesian Basin, 2007, www.gabcc.org.au/public/content/ViewItem.aspx?id=159 ; GAB transient groundwater model, 2006, http://adl.brs.gov.au/brsShop/data/gabtransient1.pdf and GAB Resource Study, 1998, www.gabcc.org.au/public/content/ViewCategory.aspx?id=41



http://adl.brs.gov.au/brsShop/data/gabtransient1.pdf

http://www.gabcc.org.au/public/content/ViewItem.aspx?id=159


Flow of water in the Great Artesian Basin – three scenarios

Early 21st-century conditions

Conditions 250 years ago (before wells): assuming spring discharge was 200,000 ML/yr

Sustainable future conditions; assuming sustainable flow from bores is 450,000 megalitres per year

What steps must be taken to move from the conditions in the top diagram to those in the bottom?

What difference would this make to the environment in the Great Artesian Basin


Lessons

Lesson 2.2Investigating artesian pressure

Outcome

Students identify the source of artesian pressure and explain its relationship to well-drilling by operating a model.


Materials

Three-metre length of 25 millimetre diameter plastic tubing or garden hose, cotton wool, large funnel, battery-powered drill, 1 millimetre drill bit, gaffer tape, large container of water, bricks or wooden blocks, metre rule or tape measure.

1. Lay the plastic tubing flat and, starting 50 centimetres from one end, drill 10 holes at 10 centimetre intervals though the top (don’t drill right through to the bottom surface). Cover each hole securely with a patch of gaffer tape – if you fold one edge of each patch under, it will be easier to remove later.

2. Fit the spout of the funnel into the end of the tubing furthest from the holes and seal with tape to make airtight.

Student worksheet

Student worksheet 2.5 Investigating artesian water – data sheet

Lesson outline

Find a grassed area or other location where some water leakage can be accommodated. Hold both ends of the tubing up and fill with water through the funnel.

Force a wad of cottonwool tightly into the open end of the tubing so that it is held firmly.

Have a student hold the funnel end at waist height and lay the rest of the tubing on the ground with the gaffer tape seals facing upward. Raise the end without the funnel about 15 centimetres and support with bricks or blocks. Point out that some water continues to seep through the cottonwool.

Pour more water into the funnel to replace any leakage. Place another wad of cottonwool firmly into the apex of the funnel. Add more water so that there is about 10 centimetres of water in the funnel.

Model of artesian pressure


Ask students how this arrangement serves as a model for an artesian basin. Discuss the intake beds, aquifer, aquitards and spring. Also discuss aspects of the model that do not represent an artesian basin well, such as the fact that the aquifer is not made of porous rock.

Simulate drilling a well by removing the tape sealing a hole midway along the tubing. Ask a student to measure and record the height of the resulting jet of water. Compare this with the height above ground of the water in the funnel. Continue to replenish water in the funnel as necessary. (Note: If the seal between the funnel and tube is not airtight, air will leak into the tube at this stage and alter the head of pressure, meaning this variable will no longer be controlled.)

Successively remove further tape patches, each time measuring and recording the heights of all jets of water. Observe any changes that can be seen in the amount of water seeping through the cottonwool.

Ask students to summarise their findings and come to a conclusion about the effects of drilling too many wells in an artesian basin.

Further student tasks

Make up two lists. In the first list, describe features of this model that are like a real artesian basin; in the second, list points of difference.

Explain what happened to the pressure in the ‘aquifer’ as more ‘wells’ were drilled. Describe any evidence for this that you saw from the modelling activity.

Describe what would happen to the ‘wells’ if the level of water in the funnel could not keep up with the water lost from the wells.

Describe how this model could be improved or modified to represent an artesian basin better.

Some people think that artesian water comes from huge underground lakes. Use your findings from this model to argue against that idea.

Explain the role of the cottonwool plug at the end of the tubing. Would it be possible for seepage of water through this plug to stop altogether?







Investigating artesian water – data sheet

Number of open wells

Height of each jet (centimetres)

Well 1 Well 2 Well 3 Well 4 Well 5 Well 6 Well 7 Well 8 Well 9 Well 10

1

2

3

4

5

6

7

8

9


INVESTIGATION 3

What impacts have humans had on the Great Artesian Basin?

IntroductionThe first artesian bore of the Great Artesian Basin was sunk in 1878. Within 30 years, there were 1,500 and now there are over 4,500. European settlers imagined that supplies of artesian water were inexhaustible, and thus undervalued it. So many wells were drilled and allowed to flow freely that pressure over the Great Artesian Basin dropped, and many bores and springs have ceased flowing. Poorly maintained, open wells and drains result in wastage of water through evaporation and allow feral animals and weeds to spread, damaging the environment. This exploitation of the resource was not sustainable.

In the early days of artesian wells, many bores flowed at rates of over 10 megalitres per day. Now, most flow at between 0.01 and 6 megalitres per day. Pressure and flow rate have decreased as more wells have been drilled, and about one-third of the wells that were artesian when drilled have now ceased to flow and require pumping. In arid regions, the flow of 80 per cent of natural springs has ceased or severely declined.

Historically, uncapped wells were common and water was distributed through open drains. Around 90 per cent of water in such drains is wasted through evaporation and seepage. And the introduction of permanent water into arid landscapes has important environmental consequences. It meant that the land could easily be overgrazed, and that weeds, pests and feral animals could flourish. Early in the 20th century it became obvious that the resource was being exploited unsustainably and that the wastage must be stopped.


Australian Curriculum Links

Science – Year 7



Biological sciences












Evaluating


Communicating





Year 7

Weather and water


weather can be a hazard, but the risks can be reduced through human adjustment to the conditions presented











Communicating







© Com

monw

ealth of Australia 2011.

Photograph by N

icole James

© Com

monw

ealth of Australia

Photograph by R

od Fensham

Lesson/case study

Lesson 3.1What’s happened to the Great Artesian Basin?

Outcome

Students investigate human impacts on the Great Artesian Basin and identify issues affecting sustainability of land and water use.



Figure 3.1 Uncapped bore and bore drain

Figure 3.2 Bore drain and weeds

Figure 3.3 Pig damage around bore drain

Figure 3.4 Drought conditions with stock being fed

Figure 3.5 Comparison of 1880 and 1970 estimated heads above ground

Graph 3.1 History of artesian bore flow in the Great Artesian Basin

Student handout/worksheet

Student handout 3.1 Consequences of artesian bores

Student worksheet 3.2 Problems with artesian bores

Lesson outline

Show students Figures 3.1–3.4. Discuss the environmental significance of each.

Figure 3.1 Uncapped bore and bore drain

Figure 3.2 Bore drain and weeds

Figure 3.3 Pig damage around bore drain


© Com

monw

ealth of Australia. G

raph courtesy of the GA

BC

C

Photograph

© Darren J C

lark

Graph 3.1 History of artesian bore flow in the Great Artesian Basin

Figure 3.4 Drought conditions with stock being fed

Point out that when settlers first found they could tap into the resources of the Great Artesian Basin, they imagined that it would be inexhaustible. The water did not need to be pumped, but flowed freely to the surface, sometimes under great pressure. Show students Graph 3.1 and ask them to answer the following questions:

– In what year was the flow rate of water from artesian bores at its greatest?

– What has happened to the flow rate since that year?

– Since that year, what has happened to the number of flowing bores?

– Considering the answers to these questions, what must have happened to the flow rate from each bore?

– Approximately what fraction of bores drilled is no longer flowing? Does this mean they cannot supply water?

– Is it true that artesian water cannot run out?


© Com

monw

ealth of Australia. M

ap courtesy of the GA

BC

C

Figure 3.5 Comparison of 1880 and 1970 estimated heads above ground

Show Figure 3.5 and discuss what it shows. (‘Head above ground’, or artesian head, refers to the height of the potentiometric surface above ground level. It tells how far above ground level the bore water will rise to, and is a measure of artesian pressure.) Ask students to point out regions where:

– the water pressure remained in the highest category between 1880 and 1970

– water pressure decreased between 1880 and 1970

– bores that were artesian in 1880 became sub-artesian by 1970.

Point out that tapping of the Great Artesian Basin has become so widespread that few areas within it are now further than 10 kilometres from permanent water. Over most of the Basin, permits have been required to drill wells but, until recently, there was little control over the amount of water that could be harvested. Historically, bores have been allowed to run freely and the water is distributed via open drains.


Distribute Student handout 3.1 and discuss the consequences that have arisen from this pattern of usage.

Ask students, individually or in groups, to devise two strategies for alleviating the issues facing the Great Artesian Basin while allowing sustainable use of the water resource. Student worksheet 3.2 could be used for this. For each strategy, there should be a detailed explanation of the outcome(s) that would be expected.






Example Non-example


Student handout 3.1

Consequences of artesian bores

About 90 per cent of the water in bore drains is wasted by evaporating and seeping into the soil.

Some bores are poorly constructed or maintained. Water leaks from the main aquifers into overlying layers and is wasted.

Water pressure and flow rate in most bores have fallen; many have become sub-artesian.

Many artesian springs have ceased to flow and the spring ecosystems lost.

Artesian water contains dissolved greenhouse gases. These are released to the atmosphere when the water flows to the surface.

Open bore drains support weeds and allow feral animals to survive.

Because water is available in lots of places, animals can graze over a wider area. This can result in overgrazing of fragile regions.

In times of drought, artesian water allows graziers to keep stock animals on their properties until feed runs out. This results in a ‘feed drought’.


Student handout 3.2

Problems of artesian bores

Description of issue 1

Strategy for issue 1

Expected outcome

Description of issue 2

Strategy for issue 2

Expected outcome


Case study 3.2Elizabeth Springs

Outcome

Students recognise the threats to groundwater dependent ecosystems associated with a mound spring .

Background

Elizabeth Springs was added to the National Heritage list in August 2009. Its fragile ecological community was listed as endangered by the Australian Government in 2001, along with similar communities across the Great Artesian Basin. As well as the Elizabeth Springs goby, the fish mentioned in the case study, the Elizabeth Springs community is home to an endemic freshwater snail and several endangered plants.


Student handout

Student handout 3.3 Elizabeth Springs – a groundwater dependent ecosystem

References

Australian Heritage Database – Place details for Elizabeth Springs, www.environment.gov.au/cgi-bin/ahdb/search.pl?mode=place_detail;place_id=105821

Enhancing biodiversity hotspots along western Queensland stock routes, www.derm.qld.gov.au/publications/docs/p203739/p203739_3.pdf

Environment Australia Action Plan for Australian freshwater fishes: Elizabeth Springs goby, www.environment.gov.au/biodiversity/threatened/publications/action/fish/8-24.html

Hydrogeological Framework Report for the Great Artesian Basin Water Resource Plan Area, pp 98–100, www.derm.qld.gov.au/wrp/pdf/gab/gab-hydrogeological-framework-report.pdf






http://www.derm.qld.gov.au/wrp/pdf/gab/gab-hydrogeological-framework-report.pdf

http://www.derm.qld.gov.au/wrp/pdf/gab/gab-hydrogeological-framework-report.pdf

http://www.environment.gov.au/biodiversity/threatened/publications/action/fish/8-24.html

http://www.environment.gov.au/biodiversity/threatened/publications/action/fish/8-24.html

http://www.derm.qld.gov.au/publications/docs/p203739/p203739_3.pdf

http://www.derm.qld.gov.au/publications/docs/p203739/p203739_3.pdf

http://www.environment.gov.au/cgi-bin/ahdb/search.pl?mode=place_detail;place_id=105821



© Com

monw


hotograph by Cam

eron Slatyer

Student handout 3.3

Elizabeth Springs – a groundwater dependent ecosystem

Elizabeth Springs

Elizabeth Springs is about 80 kilometres southeast of Boulia in Western Queensland. It is a group of more than 30 artesian mound springs, spread over about 30 hectares. They are fed from a sandstone aquifer of the Great Artesian Basin. The shallow water in the springs overflows into pools a metre or two below the mounds.

In the larger pools, darting between the water plants, are small olive-grey fish. These are Elizabeth Springs gobies, Chlamydogobius micropterus, and they are found nowhere else on Earth.

Elizabeth Springs is part of the Springvale supergroup of springs. Two centuries ago, it was one of the largest spring groups in the Great Artesian Basin. The springs covered

120 hectares and were a vital resource for the Ringu Ringu people. They fed into nearby Spring Creek, which flowed for 30 kilometres and was also home to the gobies. Today, Elizabeth Springs is the only member of the supergroup to remain active. It flows at less than 5 per cent of its former rate. The creek has ceased flowing. Loss of water through bores has dropped water pressure in the aquifer and the springs are now almost starved. Most of the water is extracted for stock and domestic use. The Osborne (copper-gold) and Cannington (lead-silver-zinc) mines to the north take water from the same aquifer.

Not long ago, the springs were being trampled by stock animals. The gobies’ habitat was being destroyed and their survival was threatened. Scientists surveyed these springs, and others


© Com

monw


hotograph by Gunther E

S

chmida

Student handout 3.3 cont.

Elizabeth Springs – a groundwater dependent ecosystem

Elizabeth Springs goby

in the Great Artesian Basin, and realised that something needed to be done. In 2001, the Australian Government declared the spring communities endangered. Elizabeth Springs was fenced to keep cattle out, but feral pigs continue to cause damage. In August 2009, the springs were added to the National Heritage List.

So far the gobies have escaped being forced out by the exotic mosquitofish (Gambusia sp.). These have appeared in other Australian waterways, carried there by waterbirds. At present, the goby population seems to be stable. The springs will need to be carefully managed to ensure they survive.

Your investigation

Artesian water is usually hot and contains dissolved minerals. How do these factors contribute to the mounds that build up around springs?

Does the Elizabeth Springs goby have any value to us? Why do scientists think it is important to save the goby from extinction?

Find out about some other plants or animals that are restricted to a single group of artesian springs. What is being done to protect them?

Suggest some strategies that managers could use to help the Elizabeth Springs gobies survive.


INVESTIGATION 4

What can be done to address the current issues facing the Great Artesian Basin?

Introduction

The Great Artesian Basin extends across four states but needs to be managed in a sustainable manner as a single system. Stakeholders need to appreciate the economic, social, cultural and environmental value of the Basin and its water, and the threats from unsustainable water use. Wastage and environmental damage from open drains must be reduced, and entitlements to the water resource must be rationalised. Endangered spring ecosystems and communities must be protected.

Although problems with the sustainable use of the Great Australian Basin were evident from the early 20th century, no structure existed to explore solutions on a Basin-wide scale until 1997 when the Great Australian Basin Consultative Council was formed to develop a management plan. The Australian Government also introduced the Great Australian Basin Sustainability Initiative www.environment.gov.au/water/policy-programs/gabsi to provide subsidies to enable landholders to rehabilitate and cap wells and install piping. In 2004, the Great Australian Basin Consultative Council was succeeded by the Great Australian Basin Coordinating Committee www.gabcc.org.au .


http://www.gabcc.org.au/

http://www.environment.gov.au/water/policy-programs/gabsi


Science – Year 7

Science Understanding Science as a Human Endeavour Science Inquiry Skills






Evaluating




Year 7

Weather and water








Lessons

Lesson 4.1The race to cap and pipe

Outcome

Students analyse strategies used to tackle the issues confronting the Great Artesian Basin and identify how they contribute to sustainability.

Background

Historically, there has been significant wastage of artesian water in the Great Artesian Basin through leakage from bores as well as evaporation and seepage from open drains. The Great Artesian Basin Sustainability Initiative (GABSI) has sought to address this situation by providing funding for capped wells and installing piping.

A well is capped by installing a system of pipes and valves at the top so that the flow of water can be turned on and off. Piping refers to the construction of a system of pipes to distribute water instead of having open-bore drains.

The pipes supply tanks and watering troughs at a distance from the well. Bores may also be rehabilitated by sinking a casing, which lines the shaft and prevents leakage into the aquifers that overlie the artesian aquifer.

Student handout 4.2 summarises some benefits and costs of capping and piping.

Resources and

preparation

Booklet

Copies of Champions of the Great Artesian Basin available for download at www.gabcc.org.au/tools/getFile.aspx?tbl=tblContentItem&id=107

Video


Student worksheet/handout

Student worksheet 4.1 Bringing sustainability to the Great Artesian Basin

Student handout 4.2 Summary of impacts from the Great Artesian Basin Sustainability Initiative

References

ABC Landline, If the cap fits, www.abc.net.au/landline/content/2008/s2636576.htm

Department of Environment and Resource Management, Queensland Government 2010, Recovery plan for the community of native species dependent on natural discharge of groundwater from the Great Artesian Basin, www.environment.gov.au/biodiversity/threatened/publications/recovery/pubs/great-artesian-basin - ec.pdf


http://www.environment.gov.au/biodiversity/threatened/publications/recovery/pubs/great-artesian-basinec.pdf



http://www.abc.net.au/landline/content/2008/s2636576.htm

http://www.abc.net.au/landline/content/2008/s2636576.htm

http://www.gabcc.org.au/tools/getFile.aspx?tbl=tblContentItem&id=107


Department of Environment and Resource Management, Queensland Government 2007, Inland waters and wetlands: Artesian bore pressure, www.derm.qld.gov.au/environmental_management/state_of_the_environment/state_of_the_environment_queensland_2007/state_of_the_environment_queensland_2007_contents/inland_waters_and_wetlands_artesian_bore_ pressure.html

Department of Sustainability, Environment, Water, Population and Communities, Australian Government, Farm costs, benefits and risks from bore capping and piping in the GAB, www.environment.gov.au/water/publications/agriculture/abridged-cie-final-report.html

Great Artesian Basin Sustainability Initiative (GABSI), www.environment.gov.au/water/policy - programs/gabsi/index.html

Great Australian Basin Coordinating Committee, Booklet: Champions of the Great Artesian Basin, 2006, www.gabcc.org.au/tools/getFile.aspx?tbl=tblContentItem&id=115

Great Australian Basin Coordinating Committee 2002, GAB Strategic Management Plan, www.gabcc.org.au/public/content/ViewCategory.aspx?id=29

Great Australian Basin Coordinating Committee, Great Artesian Basin Strategic Management Plan: Progress and Achievements to 2008, www.gabcc.org.au/tools/getFile.aspx?tbl=tblContentItem&id=365

Rolfe, John, Associated off-farm economic values of saving water and restoring pressure in the Great Artesian Basin: Report provided to the Australian Department of the Environment, Water, Heritage and the Arts, August 2008, www.environment.gov.au/water/publications/environmental/groundwater/pubs/saving-water gab.pdf


http://www.environment.gov.au/water/publications/environmental/groundwater/pubs/saving-watergab.pdf

http://www.environment.gov.au/water/publications/environmental/groundwater/pubs/saving-watergab.pdf







http://www.environment.gov.au/water/publications/agriculture/abridged-cie-final-report.html

http://www.environment.gov.au/water/publications/agriculture/abridged-cie-final-report.html

http://www.derm.qld.gov.au/environmental_management/state_of_the_environment/state_of_the_environment_queensland_2007/state_of_the_environment_queensland_2007_contents/inland_waters_and_wetlands_artesian_bore_%20pressure.html



Lesson outline

Discuss with students some of the issues facing the sustainability of water use in the Great Artesian Basin (You may wish to refer back to Lesson 3.1). Explain that institutions like the Great Artesian Basin Coordinating Committee (GABCC) and the Great Artesian Basin Sustainability Initiative (GABSI) have been set up to tackle these issues.

Show Chapter 6 of the Water Down Under video

Provide copies of Champions of the Great Artesian Basin

Provide copies of Student worksheet 4.1.

Hand out copies of Student handout 4.2. Discuss the four strategies for increasing sustainability in the Great Artesian Basin, then ask students to complete the remainder of the worksheet by referring to the video and the case studies in the booklet.








Student handout 4.1

Bringing sustainability to the Great Artesian Basin

These are some of the strategies that are being used to return the Great Artesian Basin to a balanced state:

Well casing : Wells are lined and sealed properly. This stops water leaking into rock layers that lie above the artesian aquifer.

Well capping: Pipes and taps are installed at the top of the well. They allow waterflow to be turned on and off as required. This replaces bores that flow continuously.

Piping: Water from bores is distributed through pipes which take the place of open-bore drains. The pipes supply tanks and watering troughs

A system of water entitlements:Governments control how much water each user can take. They also ensure that there is a fair distribution of water for all, including the environment.

The first column below lists some of the issues facing the Great Artesian Basin. For each strategy in the other columns, place a tick if that strategy will help in tackling that problem.

Strategy

Problem Casing Capping Piping Entitlements

flow rate and pressure in wells has fallen

artesian water releases greenhouse gases

most water in drains evaporates or leaks out

many artesian springs have stopped flowing

water can leak from artesian aquifers through wells into overlying rock layers

weeds grow around bore drains

open bores and drains support feral animals

increased access to water can result in over-grazing

In drought, open drains can trap weakened stock

Ecosystems in arid regions have been disrupted by

the introduction of permanent water

Some users see little value in saving artesian water because it seems to be inexhaustible

The Great Artesian Basin Sustainability Initiative (GABSI) has helped many pastoralists to tackle these problems. GABSI gives subsidies toward the cost of fixing bores and installing piping. Discuss whether there would be any disadvantages to capping and piping. Describe any you find.

Some people argue that capping and piping is too expensive and the cost will never be repaid. Based on what you have learned in this activity, explain why that argument is correct or incorrect.


Student handout 4.2

Summary of impacts from the Great Artesian Basin Sustainability Initiative

On-farm benefits of bore capping and piping Off-farm benefits of bore capping and piping

extended life of bores

reduced risk of bore deterioration

control of waterflow leading to management efficiencies

reduced waterlogging, salinisation and degradation associated with bore drains

increase in capital land value

reduction in the operation and maintenance expenses associated with open drains

improved water quality at delivery point

improved access around property

reduction in weeds

management saving associated with mustering

better control of feral animals and water points

improved pasture utilisation

improved drought resilience

reduced water wastage

improvement in aquifer pressure

existence value of Great Artesian Basin

existence value of landscape and ecosystem

increase in the reliability of water, leading to economic and social stability in the region

recovery of natural springs

protection of town water supplies

increased water availability for higher value uses, including mining

tourism opportunities based on artesian water

On-farm cost of bore capping and piping Off-farm cost of bore capping and piping

initial landholder expenditure on capping, piping and troughs

management changes

initial Australian and state government

expenditure on capping and piping


INVESTIGATION 5

What can I do to ensure our water is used more sustainably?

IntroductionHouseholds can contribute to the sustainability of the water supply by reducing wastage and investigating alternative sources.

Much groundwater is found not in confined aquifers, but in the pore spaces of the soil and rocks directly beneath the Earth’s surface. Near the surface, the pore spaces are not completely filled with water but, lower down, there is a saturated zone. The top of the saturated zone is known as the water table.

These are unconfined aquifers. They can be replenished by water seeping down from rainfall or lakes and rivers on the surface, and plants can tap directly into the water via their roots. When a well is drilled into an unconfined aquifer, the water can rise only as far as the water table. See Figure 5.1 and Figure 5.2 on page 72.



Science – Year 7



Biological sciences


Chemical sciences

Mixtures, including solutions, contain a combination of pure substances that can be separated using a range of techniques








People use understanding and skills from across the disciplines of science in their occupations

Questioning and predicting

Identify questions and problems that can be investigated scientifically and make predictions based on scientific knowledge







Evaluating



Communicating





Year 7

Weather and water




Communicating






Lessons

Lesson 5.1Groundwater and my household

Outcome

Students investigate the extent and nature of groundwater resources in the local area and make recommendations about drilling a well to extract water.

Background

Most regions of Australia have some groundwater resources, but the quantity and quality varies considerably from one place to another. Some urban areas, such as Perth, rely heavily on groundwater, while in other areas groundwater is used mainly for irrigation. Many aquifers, particularly in highly populated regions, are threatened by unsustainable rates of extraction or contamination from industrial sites.



Figure 5.1 Groundwater

Figure 5.2 Types of aquifers

Brochure

Understanding Groundwater, http://adl.brs.gov.au/brsShop/data/sfdm_groundwater_lores.pdf

Local resources

It could be helpful to contact a person who has knowledge of groundwater in the local area – for example, a local licensed water driller or the local council.

Student handout

Student handout 5.1 Groundwater for our household?

Lesson outline

Discuss the fact that water is a scarce resource in Australia and that many areas impose water restrictions on households. The exercise in this lesson will be to evaluate whether extracting groundwater could help to conserve water.

Give a brief general overview of groundwater, including aquifers, the water table and waterflow and show students Figure 5.1 and Figure 5.2. You may wish to refer to the brochure, Understanding Groundwater.

Ask students to research and report as suggested in Student handout 5.1.



Another option is to provide students in pairs with an unfamiliar word and using a graphic organiser with the word written in the centre, establish a definition, characteristics and a relevant example and non-example.



http://adl.brs.gov.au/brsShop/data/sfdm_groundwater_lores.pdf

http://adl.brs.gov.au/brsShop/data/sfdm_groundwater_lores.pdf

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Figure 5.1 Groundwater

Figure 5.2 Types of aquifers


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Student handout 5.1

Groundwater for our household?

Your family has asked you to investigate this question: Could our household use groundwater for some of its water supplies? You need to seek information and write a short report about your findings.

Read the brochure, Understanding Groundwater. Find out where groundwater comes from and what factors can affect its quality.

Find out whether there are good quality aquifers in your local area. Are they confined or unconfined? You may be able to ask neighbours who have bores, or you could try contacting local water-drilling contractors.

Make a list of the ways your household could use the water if it were extracted.

Some regions in Australia do not permit the drilling of new wells. Are they permitted where you live? If so, do you need a permit to drill for water or a licence to extract it? If wells are not permitted, try to find out the reasons.

Are there any likely sources of groundwater contamination in your local area? What types of contaminant could the sources release?

Does your household have any sources that could contaminate groundwater? If so, what can be done about them? Should they be reduced even if your well does not go ahead?

Are there any nearby ecosystems that could be affected if you extracted groundwater?

If your household decided to go ahead with the well, would this be a responsible decision?Is the resource being used in a sustainable manner at present or would you be making the situation worse?

Find out about Artificial Storage and Recovery (ASR), also called Managed Aquifer Recharge (MAR). Could ASR be used to relieve water shortages in your local area?

Write your report, setting out the advantages and disadvantages of extracting groundwater. Then try to balance these and come to a conclusion: What is the right decision for your household?


Lesson 5.2Does water divining work?

Outcome

Students perform a double-blind investigation to test whether water divining works.

Background

Water diviners (or dowsers) claim to be able to detect the location of underground water, usually by using a variety of instruments such as forked sticks or metal rods. There is no scientific basis for this claim, and controlled tests have repeatedly shown that it does not work. Data from early 20th century well-drilling in NSW (see the extract in the Resources and preparation section below) shows that ‘divined’ wells were less successful than ‘undivined’ wells.

In 1980, Dick Smith and James Randi organised a program of tests in Sydney to assess the ability of diviners. The tests were controlled, double-blind trials in which the success rate due to chance would be 10 per cent. Prior to the tests, the diviners claimed they would have very high success rates (averaging 86 per cent), but they achieved only 22 per cent.

A double-blind test attempts to eliminate the possibility that both the subject and the experimenter could influence the results of the test through bias or the inadvertent exchange of information. It requires that neither party has prior knowledge of how the control and experimental variables are arranged. In this case, they must not know the location of the water.



Table 5.1 Design for a water-divining test

Materials

bottle of water, at least 5 containers to hide the water bottle

Student worksheet/handout

Student handout 5.2 Divining success rate: A major study in NSW, Australia

Student worksheet 5.3 Data recording sheet for water-divining experiment


References

Australian Skeptics divining test, www.skeptics.com.au/publications/articles/australian-skeptics-divining-test

James Randi water-divining video, http://video.google.com/videoplay?docid=7461912885649996034#

The Mighty Mitta Muster water-divining test (video), 2002, http://video.google.com/videoplay?docid=4694530584288972114

Richard Saunders water-divining test (video), www.youtube.com/watch?v=q_mWZWDcqK4&feature=player_embedded

USGS Water Dowsing Report, http://pubs.usgs.gov/gip/water_dowsing/pdf/water_dowsing.pdf

Lesson outline

• Discuss the phenomenon of water divining or dowsing, including some methods and whether it is likely to be valid. Some students may be able to relate experiences with diviners.

• Explain that this phenomenon can be tested scientifically. It is possible to make a hypothesis about water divining which specifies an outcome that can be measured. A suitable hypothesis could be developed at this stage, for example, ‘If a person can divine water, he/she should be able to consistently find a hidden container of water with better than chance results’.

• Discuss the requirements for a good scientific test of this hypothesis. Elaborate on the reasons for each:

– The test must be controlled. One variable should be changed while others are controlled.

– Subjects need to fit the criteria being tested.

– The effect must potentially work under the experimental conditions.

– Subjects must be unaware of changes to variables (blind test).

– Testers must be unaware of changes to variables (double-blind test).

– The result of each test must be clearly measured.

– Repeat trials must be carried out.

– In interpreting the results, chance must be taken into account.


http://pubs.usgs.gov/gip/water_dowsing/pdf/water_dowsing.pdf

http://pubs.usgs.gov/gip/water_dowsing/pdf/water_dowsing.pdf

http://www.youtube.com/watch?v=q_mWZWDcqK4&feature=player_embedded

http://www.youtube.com/watch?v=q_mWZWDcqK4&feature=player_embedded

http://video.google.com/videoplay?docid=4694530584288972114




http://www.skeptics.com.au/publications/articles/australian-skeptics-divining-test

http://www.skeptics.com.au/publications/articles/australian-skeptics-divining-test

Guide the class in designing a test to take account of these requirements. Table 5.1 shows a possible design.

Design for a water-divining test

Refer students to Student handout 5.2. Read the extract with the students and then discuss the data and the conclusions drawn about the effectiveness of water divining. Explore the strengths and weaknesses in the method of measuring the divining success rate and whether the data presented in the chart really supports the conclusions.

Carry out the series of tests using the method chosen by the class. Refer to Student handout 5.2 for an example of a table that could be used to record the data. Have students record their results in Student worksheet 5.3.

Examine the results, comparing the actual success rate with that expected by chance. Ask students to derive a conclusion by deciding whether the hypothesis has been supported or rejected.

Review the experiment, discussing any improvements that could be made if the test were to be repeated.






Table 5.1 Design for a water-divining test

Requirement Suggested strategy

The test must be controlled. One variable should be changed while others are controlled.

A bottle of water will be hidden and the subjects asked to locate it. There will be at least five numbered hiding positions around the room, separated by reasonable distances, and the bottle will be placed randomly in one of them. The empty positions are the controls. To ensure random selection, numbered cards could be placed in a box, with one card drawn for each test.

Subjects need to have demonstrated the ability to ‘divine’ water.

Carry out initial trials with members of the class. Put a bottle of water on a table and find students who can ‘locate’ it using the divining devices.

The effect must potentially work under the experimental conditions.

Before the test, check whether the subjects can ‘locate’ the bottle while it is hidden in a known position. To save time, it could be convenient to make all the hides identical (eg cardboard cartons) so that a single check will suffice.

The subject must not know in advance the true position of the bottle.

Each subject must leave the room while the hiding position is selected and the bottle is hidden.

The testers must not know in advance the true position of the bottle.

All observers must leave the room while the hiding position is selected and the bottle is hidden. There must be at least one person who hides the bottle. The hiding position should be chosen randomly (eg by drawing a card) to prevent any pattern emerging. Anyone who knows the position of the bottle must then leave the room while the test is performed.

The result of each test must be clearly measured.

Each subject must state clearly where the bottle is believed to be within a reasonable time. This will be recorded by the testers. The true position of the bottle will then be revealed and recorded.

Repeat trials must be carried out.

The method will be repeated several times, with a new randomly chosen position for the bottle each time.

In interpreting the results, chance must be taken into account.

If there are five hiding places, a person without any divining ability would be expected to guess the correct position in one trial out of five. If divining works, it should give better results.


Student handout 5.2

Divining success rate: A major study in NSW, Australia

There is no body of evidence, so far as the writer is aware, so valuable for assessing the claims of divining as that which has been gathered and recorded by the Water Conservation and Irrigation Commission of New South Wales in connection with the shallow drilling carried out for settlers in central New South Wales. The drills are operated by the Commission, and the drill foreman has to report at the outset of the work whether or not the site has been divined. The settlers are not influenced in any way in the fixing of bore sites, and some of them have made their own selection, while others have taken the advice of diviners. From these reports the Commission has compiled the following table, which deals with all the boreholes drilled between 1918 and the end of 1943.

Classification of BoreholesDivined Not divined

Number Drilled

Per cent Number Drilled

Per cent

Bores in which supplies of serviceable water, estimated at 100 gall. per hour (approx. 0.12 L/sec) or over, were obtained

1284 70.5 1474 83.8

Bores in which supplies of serviceable water, estimated at less than 100 gall. per hour, were obtained

184 10.1 93 5.3

Bores in which supplies of unserviceable water were obtained 87 4.7 60 3.5

Bores which were absolute failures, no water of any kind being obtained 268 14.7 131 7.4

The districts within which these boreholes were drilled have a yearly rainfall ranging from nearly 30 inches [approx. 750 mm] to under 15 inches [approx. 375 mm] in the extreme west. The northern part of the area embracing the boreholes lies largely within the Great Artesian Basin, with a consequent material reduction in the risk of failure. Yet it will be seen that the proportion of failures at divined sites is nearly double that at sites not divined, while the percentage of highly successful drillings is far greater at sites not divined than that at the divined sites. The very large number of boreholes embraced in the tabulation corrects the deficiency that has been felt by those who have tried to discuss divining in the light of the records dealing with a small number of cases, some of which may have been selected, and omitting any reference to the failures that must certainly have occurred.

Extract from Geological Survey of South Australia, Bulletin No. 23, 1946

Reproduced with permission from the Geological Survey of South Australia



Data recording sheet for water-divining experiment

Subject:

Trial Number 1 2 3 4 5 6 7 8 9 10

Detected location

Actual location

Success rate expected by chance: out of ( _ %)

Actual success rate: out of ( _ %)

Subject:

Trial Number 1 2 3 4 5 6 7 8 9 10

Detected location

Actual location



Subject:

Trial Number 1 2 3 4 5 6 7 8 9 10

Detected location

Actual location




GLOSSARYaquifer

A layer of rock or soil that can absorb and hold water and allow it to flow through.

aquitard

A layer of rock that does not allow water to pass through.

arid

A region lacking sufficient water or rainfall.

artesian basin

A system of sedimentary rock layers containing aquifers that can store and transport water that is under pressure.

artesian bore

A bore hole that is drilled into a confined aquifer containing groundwater. This enables water, which is under pressure, to flow upward through a well to the surface.

artesian head

The height above ground level to which artesian water will rise when a shaft is drilled into the aquifer; also known as ‘head above ground’.

artesian spring

A spring formed at a place where water leaks to the surface from a confined aquifer, either because the aquifer is exposed or a fault has fractured the aquitards.

artesian water

Groundwater that is under pressure in a confined aquifer so that, when the aquifer is tapped by a bore, the water flows naturally to a level above the land surface.

biodiversity

A measure of the variety of living things in a particular region.

capped well

An artesian bore or well which has pipes and taps installed at the top so water flow can be turned on and off as required. This prevents the bore flowing continuously.

confined aquifer

An aquifer with impervious layers above and below, so that water can flow only sideways.

contamination

The act of adding harmful substances to a pure substance such as water.

discharge

The release or free flow of water from a well or a spring.

double-blind investigation

Describes a controlled scientific trial in which neither the experimenters nor the subjects know who is in the experimental group or who is in the control group.

ecosystem

A community of living things and the physical environment which supports it.

endemicFound only in a particular locality.

82 | A unique river system worth maintaining The Lake Eyre Basin

exotic

Not native; originating from another country.

feral

Surviving in the wild after escaping from domestication.

flow rate

The amount of water that flows from a well or a spring over a particular period of time. Flow rates are expressed in units of volume and time such as litres per hour or megalitres per year.

gigalitre (GL)

One thousand million (or 1 x 109) litres.

greenhouse gases

Gases that trap infrared radiation and thus contribute to the warming of the Earth’s atmosphere by the greenhouse effect. The principal greenhouse gases are water vapour, methane, carbon dioxide, nitrous oxide and ozone.

groundwater

Water filling the pore spaces or cracks in soil or rock beneath the Earth’s surface.

groundwater dependent ecosystems (GDE) Ecosystems that depend on groundwater for their survival. They include ecosystems found in artesian springs, caves, swamps, wetlands and stream banks.

head above ground

The height above ground level to which artesian water will rise when a shaft is drilled into the aquifer; also known as ‘artesian head’.

hypothesis

A proposed explanation for a phenomenon; it remains tentative until tested.

hypothetical

A suggested but unproven explanation of some observed reality or phenomenon.

impermeable

Does not allow water to pass through.

impervious layer

A layer of rock or sediment that will not let water through.

infiltration

The downward flow of water from the surface into the soil or rock.

intake beds

Places where rain or surface water soaks into an exposed aquifer; also known as ‘recharge areas’.

interbedded

Arranged in alternating, horizontal layers (often referred to as beds by Earth scientists).

isohyet

A line on a map joining places of equal annual rainfall.

kilopascal

A measurement unit of force or pressure per unit area. A kilopascal (kPa) equals 1,000 pascals of pressure per square metre.

megalitre (ML)

One million (or 1 x 106) litres.

Glossary | 83

mineral load

The amount of minerals dissolved in a particular volume of water.

mound spring

An artesian spring that is surrounded by a conical mound built up from sediment and minerals deposited by the water.

National Heritage List

An established list of places (natural, cultural or historic) of outstanding heritage significance and value to Australia. Special Australian Government laws and agreements protect listed places. The National Heritage List is compiled and maintained by the Department of Sustainability, Environment, Water, Population and Communities.

non-permeable

Does not have holes or pores and, therefore, does not allow fluids to be absorbed.

permeable

Allowing water to pass through via pore spaces or cracks.

piping

The provision of pipes to carry and distribute water from bores to troughs and tanks rather than have the water travel along open drains.

pituri

A plant used ceremonially and socially as a drug by the Australian Indigenous people; one of the active components is nicotine.

porous

Having pores, or small spaces, and thus able to absorb water.

potentiometric surface

Indicates how high above ground level artesian water will rise over a particular area.

recharge areas

Places where rain or surface water soaks into an exposed aquifer; also known as ‘intake beds’.

rehabilitate

To restore to good health a former habitat that has been damaged or lost by such events as overuse, overgrazing or feral animal invasion.

salinisation

A build-up of salt in the soil as a result of a rising water table which brings water containing dissolved salt from deep sediments.

sedimentary

Formed from the settling and compaction of sediment.

songlines

In Indigenous belief systems, these are paths followed by creator-beings during the Dreaming, passed down through generations via songs, stories and dance.

spring complex

As applied to artesian springs, a group of related springs found within an area a few kilometres square.


sub-artesian

Groundwater that rises naturally in a well to a height above that of the surrounding water table but does not have sufficient pressure to flow freely out of a well and requires pumping to be extracted.

supergroup

As applied to artesian springs, a collection of spring complexes spread over a geographical region.

sustainability

The ability of an activity, resource or ecosystem to be maintained into the future without declining in quality and abundance.

sustainable

Able to be continued for a long time without serious change.

uncapped well

An open well or bore that has been drilled into an aquifer allowing a natural and continuous flow of water. Uncapped wells can waste water because they do not have a cap or tape to control the flow.

unconfined aquifer

An aquifer with a water table, above which water can seep downwards from the surface.

unsustainable

Cannot continue at the current rate or level.

upward leakage

Leakage of water from the artesian groundwater upwards into the water table or soil.

variable

Able to or likely to change (adjective); a quantity which is able to be changed during an experiment (noun).

water divining

Any method which claims to locate underground water using techniques that have no scientific basis; also known as ‘water dowsing’.

water entitlement

A government-regulated allowance of how much water can be taken from the springs or bores over a period of time. Entitlements are issued to particular property owners or other users to ensure fair and sustainable distribution of water and the protection of the environment.

water table

The upper surface of the zone where the pores of soil are totally filled with groundwater; above the water table there is some air in the pores.

well casing

The process of ensuring that bore and well drill holes are lined and sealed to ensure water is not lost through its seepage into rock layers above the artesian aquifer.

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Documents

Water in the dry interior - The Great Artesian Basin ... Web viewTeacher guide and lesson plan ... It consists of a system of sedimentary layers which were laid down ... horizontal