RESEARCHER’S FORUM
“Implications for Groundwater access, Extraction and
Groundwater Dependent Ecosystems”
March 2013
Acknowledgements
The GABCC would like to acknowledge the Forum Theme Leaders Dr Brian Smerdon, Assoc. Prof.
Andy Love, Mr Travis Gotch and Mr Peter Baker for their considerable leadership and assistance
during the planning and implementation of the GAB Researchers Forum. The Forum organising
committee members (Lynn Brake, Moya Tomlinson, Saji Joseph, George Gates, and Alistair Usher) are
to be commended for generously providing their time and expertise to assist the planning of the
Forum. Last but by no means least Gayle Partridge and Paul Hardiman are also recognised for their
energy and enthusiasm in the lead up to the Forum, and their active participation helping to
successfully implement the event.
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This report should be attributed as the Great Artesian Basin Coordinating Committee Researchers
Forum March 2013, Great Artesian Basin Coordinating Committee, 2013.
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supplied by third parties.
Executive Summary
The Great Artesian Basin Coordinating Committee’s GAB Researchers Forum (the Forum)
held 27 & 28 March 2013 in Adelaide brought together approximately 100 invited guests
from a diversity of GAB sectors including research, government and industry for the purpose
of sharing GAB related knowledge and experience, and potentially filling previously
identified GAB knowledge gaps.
The Forum delivered the opportunity to communicate 22 presentations providing results of
a diversity of significant contemporary GAB related research projects. These research
results, together with other relevant research were consolidated in a subsequent workshop
sessions. The outcome of the workshop session was to identify and prioritise contemporary
GAB research and knowledge gaps, and then scope out potential research projects to
address priority knowledge gaps.
The centerpiece of the Forum was the public release of two significant GAB Research
Projects, the GAB Water Resource Assessment and NWC Springs Project, representing
approximately $23M of Commonwealth, South Australian Government and stakeholder
investment. The Projects were launched by the Commonwealth Parliamentary Secretary for
Water, together with South Australian Minister for Water and River Murray, and directors
from the respective research organisations and Chair of the GABCC.
The Forum combined the communication of hydrolgeological and ecological research
outputs in a way that had not been attempted in previous GAB fora. Significant synergies
and new perspectives were identified between and within both hydrogeological and
ecological type research outputs. The Forum also provided an opportunity for collaborative
linkages to be forged between specific GAB researchers and broader GAB stakeholders.
Context
The Great Artesian Basin (GAB)
The GAB is truly an iconic Australian water resource and still largely remains an unsung
hero. It has sustained Aboriginal people for thousands of years and now supports a wide
range of communities, enterprises and industries.
The GAB is one of the largest underground water reservoirs in the world. It underlies
approximately one fifth of the Australian continent, encompassing largely arid and semi-arid
landscapes to the west of the Great Dividing Range.
The GAB is a ‘confined’ groundwater Basin comprising a complex multi-layered system of
water bearing strata (aquifers) separated by largely impervious rock units. The water yielded
by the aquifers is predominantly fresh and in most areas under sufficient pressure to
provide a flowing water source when tapped by the drilling of bores. Natural outflows occur
at artesian springs. These artesian springs support a diverse array of wildlife in the arid
regions.
The major issue in the GAB today is the sustainable use of its groundwater resources. In
recent years, close to 600,000 megalitres per year of groundwater has been extracted by
bores in the GAB, of which the pastoral industry accounts for over 85%. However, with
potential extractive industry development within the GAB, the volume of co-produced GAB
water is set to increase. A Strategic Management Plan for the GAB (the Plan) was released
in September 2000 (http://www.gabcc.org.au/public/content/ViewCategory.aspx?id=29).
The Plan incorporates national policy principles on groundwater management, sustainability
and biodiversity, and complements State and Territory water resource legislation. This
helps to ensure that Basin-wide considerations and principles are kept in focus during
detailed planning and implementation at the State, Territory and regional level.
Ongoing cooperative management of the GAB water resource by government, industries
and communities, based on improved information, effective legislation, advanced
technologies and strong partnerships will ensure sustainable use of the treasure that is
Australia’s Great Artesian Basin.
Great Artesian Basin Coordinating Committee (GABCC)
The work of the GABCC is largely shaped by the Strategic Management Plan for the GAB.
The GABCC was established early in 2004 to replace the Great Artesian Basin Consultative
Council, which ceased operation in December 2002.
The primary role of GABCC is to provide advice from community organisations and agencies
to Ministers on efficient, effective and sustainable whole-of-resource management and to
coordinate activity between stakeholders.
The GABCC is comprised of multi-sectoral representation from government, agriculture,
environment, indigenous and industry tasked with advising on the sustainable whole-ofbasin management of the Great Artesian Basin. One on the functions of the GABCC is to
promote and foster ongoing knowledge and research of key GAB knowledge gaps. To this
end the GABCC maintains a Research Development (R&D) prospectus (and funds a GABCC
PhD Top-up scholarship program to foster engagement with early career academics
promoting opportunities to fill these knowledge gaps).
Further information on the operation of the GABCC Research and Development prospectus
may be found at http://www.gabcc.org.au/public/content/ViewCategory.aspx?id=73
GAB Researchers Forum Background
One of the key stated objectives of the GABCC is to promote and foster ongoing knowledge
and research of key GAB knowledge gaps. To meet these objectives the GABCC has
previously implemented a range of events (including GAB research forums), the last of
which occurred in 2005. On 27 & 28 March 2013 the GABCC sponsored a GAB Researchers
Forum around a centrepiece of launching the findings of two significant GAB research
projects, the Great Artesian Basin Water Resource Assessment and the Allocating Water and
Maintaining Springs in the Great Artesian Basin project.
GAB Researchers Forum Aim
The aim of the Forum was to communicate a range of contemporary GAB research findings
and facilitate discussion between research stakeholders. Attendees to the Forum received
presentations on the key GAB research (including knowledge gaps and implications for
management) whilst also being provided the opportunity to participate in targeted
workshops.
New Great Artesian Basin Conceptualisations
The findings of the GAB Forum will guide government and community decision making and
inform development of high quality water policy. The Forum findings are intended to inform
resource planning, management and investment decisions through the provision of quality
data that is reliable and fit-for-purpose.
Contemporary Great Artesian Basin Research
Great Artesian Basin Water Resource Assessment (GAB WRA)
The GAB WRA provides an analytical framework that may be used by governments, industry
and communities to inform resource planning and management and investment decisions
through the provision of quality, reliable and fit-for-purpose data. Prior to the initiation of
the GAB WRA there was an increasing demand to understand the hydrogeology of the GAB
water in light of recent extractive industry development within the Basin, including coal
seam gas and mining, so it was considered timely to assess and update the latest geological
and hydrological information to support its management.
GAB WRA at a glance:

A two and a half-year $6.25 million project to assess water resources in the Great
Artesian Basin (GAB) has been completed by Australia’s key research organisation the
CSIRO, in collaboration with Geoscience Australia .

This is the first comprehensive study of the GAB aquifers since 1980.

The Great Artesian Basin Water Resource Assessment builds on previous Sustainable
Yields studies.

CSIRO lead the two and a half year Assessment, with significant contribution from
Geoscience Australia. Important aspects of the work are being undertaken by Sinclair
Knight Merz, Flinders University, South Australian Department of Environment, Water
and Natural Resources, and MA Habermehl Pty Ltd.

The GAB WRA findings highlights that vertical groundwater movement is more
important than previously thought, which will affect its management.

It is important to understand the complex structure of the GAB, because geological
features such as faults, ridges, connection to adjoining geological basins determine the
groundwater conditions, including pressure and salinity and how they respond to
change.
Allocating Water and Maintaining Springs in the Great Artesian Basin
(Mound Springs project)

The four-year $17 million Mound Springs project, funded by the National Water
Commission and the South Australian and Northern Territory Governments, pulled
together a number of project partners including: the South Australian Arid Lands NRM
Board, Flinders University, Adelaide University, CSIRO, and the South Australian and
Northern Territory Governments.

Recognising that sound water planning and management requires a sound knowledge
base, this project has made substantial contributions to our scientific understanding of
the GAB in practical ways that will assist water management into the future. In
particular:

For the first time, the locations of all springs in the western margin of the GAB have
been mapped and recorded, and baseline condition assessments undertaken. This
provides an essential baseline against which to assess the effect of current and
future management actions.

The biodiversity value of the iconic GAB springs has been reinforced through genetic
analyses that identified 25 new species of invertebrates that are endemic to the
springs. The springs are already known to support rare and endangered ecological
communities that are recognised under the Commonwealth’s EPBC Act 1990.

The water balance for the NT and SA portions of the GAB has been refined using a
number of scientific methods to estimate various types of recharge and discharge
processes. This new information challenges long-held management assumptions that
the GAB is in a steady state.

New and cost-effective techniques to monitor spring flow rates and ecosystem
responses have been developed as a result of this project. These techniques will help
provide the information that is needed for informed management decisions.

The project has also developed a risk assessment framework to assess the response
of GAB springs and their unique ecosystems to reductions in aquifer pressure, either
from long-term natural decline or human impacts.

Translating the project’s research findings into improved water planning and more
sustainable management will be a significant and important challenge for the NRM
board, governments, local communities and industry into the future.
GAB Researchers Forum - Methods
Forum Presentations
The Forum was divided into three themes including GAB from the east, GAB from the west
and GAB ecology. A leader was nominated for each theme and Dr Brain Smerdon, Ass Prof.
Andy Love and Mr Travis Gotsch as recognised experts in their respective fields, agreed to
lead each of the respective themes.
Forum Presentation Themes
The titles of presentations provided under each of the three themes are listed in text boxes
below.
Theme 1: Hydrogeology – GAB from the East
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Theme 1 Leader – Dr Brian
Smerdon (Photo: Gayle Partridge)


Interconnectivity within the Surat CMA.
Results of trial aquifer injection programs in the
Surat Basin.
Modelling the impact of mining on groundwater uncertainty and upscaling.
Summary of Office of Water Science projects and
bioregional assessments in the GAB. Great
Artesian Basin Water Resources Assessment –
overview and key findings.
Great Artesian Basin Water Resources Assessment
- updates to the geology of the GAB.
An integrated approach to geoscientific basin
models using 3D formats and visualisation
Theme 2 : Hydrogeology– GAB from the West
Theme 2 Leader- Assoc. Prof. Andy
Love (Photo: Gayle Partridge)
Upwards leakage around the southwestern margin of the GAB.
 Mound Formation.
 GAB recharge – South Australia. Diffuse recharge &
mountain system recharge along the western margin of
the GAB.
 GAB recharge – Northern Territory.
 Conceptual model uranium series.
 Groundwater chemistry and acid sulfate soil issues.
 Steady state and transient modelling issues.
 Diffuse discharge.
 models using 3D formats and visualisation
Theme 3: GAB Ecology
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
Theme 3 Leader - Travis Gotch
Photo unavailable
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South Australian perspective, including summaries
of NWC project outcomes.
Towards a comprehensive database for the GAB springs
with an update on recent progress in Queensland and
New South Wales.
Remote sensing advances in spring management.
Groundwater dependent ecosystems - mapping in the
Qld GAB.
The Evolution and biogeographic history of the endemic
invertebrate community inhabiting South Australian
mound springs.
GAB spring fish management and conservation; a case
study from Edgebaston, Queensland.
Impacts of CSG on springs in the Surat CMA.
Evaluating risks to GAB springs.
Forum Workshops
The remaining knowledge gaps were captured and were considered by attendees during
group work exercises which would contribute to the update of the GABCC Research and
Development (R&D) prospectus.
To progress key outcomes of the GAB Researchers Forum it was proposed that:
a) the ranked key research priorities and gaps, identified at Table 1, be used to update
the GABCC Research and Development Prospectus, for the endorsement of the GABCC;
and
b) That draft GAB research projects (see Table 2) be published on the GABCC website,
and also be promoted to relevant agencies responsible for funding GAB related
research.
Forum Workshop sessions
The workshop sessions were implemented in the final phase of the Forum to consolidate
the skills and experience of all workshop attendees, and provide clear advice on research
priorities and potential projects to be considered in GAB water policy and future rounds of
GAB related research investment.
Workshop – Ranking of priority research gaps and scoping of potential research projects
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Each presenter was asked to nominate 1-2 knowledge gaps, which were recorded on white boards during the
Forum.
Attendees were also given the opportunity to nominate knowledge gaps (via post-it notes on Forum wall).
At the commencement of the Forum (registration) attendees were asked to self nominate themselves into
categories of Hydrology, Ecology, Industry, Geology, Social or Government. Each category had a coloured dot
to be attached to the presenters name tag.
Prior to the start of the session facilitators arranged to print out all the identified knowledge gaps as a
reference for each attendee, for those gaps that have been identified by multiple respondents the number of
respondents will also be listed.
At the start of the session attendees were asked to split into table groups that contain people with THE SAME
“dot” colours.
Each table nominated a Table leader. Table groups were then be asked to rank (by consensus) the listed
knowledge gap by descending priority.
Table groups were nthen asked to provide a brief scope for a potential research project to address the top 1- 2
ranked knowledge gap. Attendees were advised that no funds are available to support any proposed research
project, but the scoping document could be used to assist potential GABCC Scholarship Applicants tailor their
proposed research programs.
Plate 3: Chair GABCC Technical Working Group – Mr Peter Baker
Forum Results
Contribution of sessions to GABCC R&D Prospectus
The GABCC has identified important knowledge gaps in a range of research areas and
actively encourages students and researchers to provide proposals to address priority
research questions grouped under the following five key knowledge streams below:
1.
2.
3.
4.
5.
Understanding the resource
GAB access infrastructure
Monitor and measure
Higher value measure
Valuing investment
In the tables below a brief summation of each Forum presentation (blue boxes) and
potential research projects (red boxes) have been mapped to each of the five key
knowledge streams identified under the current GABCC Research and Development
prospectus.
Detailed abstracts for selected Forum presentations are at Appendix 3.
Gross Forum Outcomes
Knowledge Stream A – Understanding the resource
The structure and function of the GAB has been researched for more than a century. Natural
discharge, and the ecology of springs and soaks, have also been investigated. Monitoring of
bores have also contributed to knowledge about the GAB and its management. However,
the GAB is a very extensive and complex aquifer system, and knowledge gaps still limit the
reliability of management and investment decisions, particularly in relation to
understanding or quantifying uncertainty around groundwater flow and groundwater
surface water interaction.
Stream A - Presentations
GAB Ephemeral River recharge –
Northern Territory.

Sixth of NT is covered by GAB
and one sixth of the GAB is in
NT
 Finke is the largest source of
recharge.
 The recharge is reducing and is
less than 0.002% of storage.
Therefore fossil resource
 Recharge estimates have
driven policy change in the NT
re water allocation framework
 Recharge zones are coincident
with high quality potable water.
This coincides with water
supply for communities. This
then creates vulnerability to
climate change.
Hydraulic Head issues.

GAB recharge – South Australia. Diffuse recharge
& mountain system recharge along the western
margin of the GAB.

Regional recharge less than 1mm/year
– therefore fossil resource use.
Diffuse discharge.

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Preferential discharge
Setting long term extraction limits for
groundwater allocation
Existing groundwater models
overestimate upward leakage
Variable density of water in parts of aquifers being tested using bores can lead to
errors in predicting direction of groundwater flow.
Water density mainly varies with temperature
Darcy’s law used to determine potentiometric pressure gradients. A conversion is
required to take account of the variable density. The conversion involves
assuming the water in the test bore is fresh.
If conversion is not made the direction of flow predicted may be incorrect.
There is no standardised approach to applying the correction – this is an area for
research.
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Upwards leakage around the southwestern margin of the GAB.
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Explaining water balance from evaporation from phreatic zone from upward
leakage concept.
Used remote sensing – salt precipitate/surface moisture.
Works in lower lying areas. Where higher upslope water table is lower down and
effect is not detected by the remote sensing technique.
Mgmt driver is reducing uncertainty in the water balance and to provide insights
into harvesting vertical leakage.
Also data to test water balance and improve modelling
Mapped spatial distributing of high leakage zone basis for improving regional
water balance.
Stream A – Potential Research Projects
a) Qualification and Quantification of horizontal and vertical structural controls on
Groundwater Flow both within and between GAB aquifers and interconnected
overlying and underlying aquifers
Management issue identified
by research & describe how
research will assist in
managing the issue.
Research description including
literature review, field
sampling or survey, field or
laboratory experiments.
Experimental methodologies,
sample size and analysis tools.
Stakeholders to be consulted
Identify how the proposed
research relates to existing
research, particularly any
cross-disciplinary connections
The purpose of the research is to enable more robust
management that the structural complexity of the GAB.
The research is relevant to the following management
issues;

Closing the water balance

Harvesting upward leakage

Connectivity with underlying basins

Interpolation of monitoring data
Quantification of fluxes literature

Costelloe et al.

Harrington et al.
Mapping and Identification literatures

Seismic

Land sat and aerial photographs

GAB WRA

Unconventional gas industry

Mining industry

Geoscience Australia

Office of Water Science
Extension and collaboration with current projects
looking at

Polygonal faulting (GAB WRA)

Diffuse discharge (AWMSGAB)

Evaporation (Uni of Melb)
Cross-disciplinary

Geophysics

Structural geologists

Hydrogeologists

Remote sensors
Describe your research design,
including literature review,
field sampling or survey, field
or laboratory experiments.
What methodology will you
use throughout your project?
How will you identify your
research sample? How will you
collect and analyze data?
Research is designed to estimate diffuse and vertical
leakage attributed to Polygonal and regional faults.
Include a rough cost estimate;
the cost estimate should
include people and resources
Significant drilling/analysis budget ($15M)
List any deliverables that are
related to the research
Field sampling to involve multi-level coring and multisections.
Field or laboratory experiments to include traces,
physical properties and hydraulic tests.
Staffing 5FTE for 3 years $3M
Total budget $18M

Mapping of structural/sections/fluxes

Conceptual models
b) – Qualification and Quantification of the Winton/Mackunda Aquifer and underlying
aquitard. “A Portrait of the Rolling Downs Group, a neglected aspect of the GAB”
Management issue identified
by research & describe how
research will assist in managing
the issue.
Quantification of a major but poorly understood part of
the GAB water balance.
Hypothesis, idea or premise to
be tested by the research
question
Aquifer – structural integrity and hydro dynamics –
recharge estimates.
Current water balance excludes processes occurring in the
Rolling Downs Group.
Aquitard – structural integrity and hydro dynamics.
Is there upward leakage? Trialing a variety of applicable
methods and techniques.
Stakeholders to be consulted
Water planners and mangers in Commonwealth and
State Governments.
Consult:
Identify how the proposed
research relates to existing
research, particularly any crossdisciplinary connections

Water planners

Industry

Land holders and water users

Traditional owner
Builds upon conceptual work of GAB WRA and West GAB
spring studies.
Improved water balance will contribute to effective and
informal management of the resource. Remote sensing.
Research description including
GAB WRA 2013, AWMSGAB Vol 1,2 & 3
literature review, field sampling Conceptual model for polygonal and structural disruption
or survey, field or laboratory
Knowledge gaps – Quantitative estimates of fluid flow in
experiments. Experimental
key regions.
methodologies, sample size
and analysis tools.
Knowledge Stream B – GAB access infrastructure
Governments and landholders have worked cooperatively to invest in the best science and
technology available to rehabilitate bores, improve water delivery infrastructure and change
practices to ensure that water is used judiciously. Substantial gains have and are being made
in eliminating waste and restoring pressure. These investments need to be protected.
Stream B – Presentations
Results of trial aquifer injection programs in
the Surat Basin.

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Water management policy lists
aquifer injection as a preferred
outcome.
Possible issues:
o change in pressure from
injection
o Water quality issues
o “clogging”
Need for very careful monitoring
Need for development of injection
management plans
Investigation of feasibility:
o Technical
o Economic
o Socio - environmental
Great Artesian Basin Water Resources
Assessment - updates to the geology of
the GAB.
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Vertical leakage issue
Likely to be both recharge into
and discharge from the GAB to
overlying alluvial aquifers.
Where discharge is into alluvial
aquifers much of the water is
removed for irrigation (e.g.
Condamine, Gwydir and
Namoi).
Polygonal Sault Systems are
extensive across the GAB –
result in preferential flow and
upwards leakage which, when it
occurs into alluvial surface
aquifers, is lots to
evaporation/evapotranspiration
Stream B – Potential Research Projects
a) Qualification and Quantification of the response of spring systems to closures of a
high flowing South Australian GAB bore (Big Blythe)
Management issue identified
by research & describe how
research will assist in managing
the issue.
Three linked projects:
1. Monitor pressure recovery.
Multi-level
piezometer to examine recovery in connected
overlying and underlying strata.
2. Monitor recovery of spring flows in Freeling
springs – understand relationships between
spring flow rates and aquifer pressure.
3. Monitor recovery/expansion of Freeling Springs
ecosystems to improve understanding of ability
of spring ecosystems to rebound from short or
long-term decline in flows.
Knowledge Stream C – Monitoring and measurement
Jurisdictional water plans have identified a requirement for monitoring pressure and
environmental flows. Although monitoring is primarily the responsibility of the jurisdictions,
information collected supports both Basin-wide and local assessment needs for planning
purposes. Consistency in approach and data collected is vital to a whole-of-resource
assessment. Further investigation of monitoring approaches is needed, with a view to cost
and the ability to accommodate the complexity of the aquifer structure of the GAB within
future monitoring programs.
Stream C - Presentations
Modelling the impact of mining on
groundwater - uncertainty and upscaling
from developments such as CSG.
Great Artesian Basin Water Resources
Assessment (GAB WRA) – overview and key
findings.
Impacts can be significant but not measurable
at the scale of data

Therefore models are needed for upscaling
result, especially for cumulative impacts over
regional scales.

A range of different modelling techniques
yield varying results, some of which are quite
promising.
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Groundwater flow models – coverage
of whole basin as well as some regional
models.
Modelled effects effects of future
climate
Changes in ground water level
Risks to springs
Updating conceptualisation of the GAB
Reconsideration of GAB boundary
An integrated approach to development of geoscientific basin models using 3D formats and
visualisation.
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Utility in displaying multiple uses of resources in one diagram and can integrate a range
of resources. e.g. – pastoral, mining, petroleum, gas, unconventional industries, tourism
etc.
Can deal with overlapping tenure. – conceptual hydrogeological models.
Models need to be useful.
These visual models can be very useful for communicating ideas to managers,
regulators, community
Conceptual model and steady state and transient modelling issues
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Science needed to inform management and policy
Need to use transient rather steady state models otherwise available water may be
overestimated
Faulting is most important for water transfer – preferential leakage
Need to look at total leakage to get water balance
Linkage between mantle and GAB Springs – vertical connection throughout the GAB
Diffuse leakage is smaller than preferential via faults
Remote sensing advances in spring management.
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Detailed inventory of wetland and substrate characteristics
Monitoring of trends in entire wetlands and key communities
New understanding of variability over time, climatic & management influences
New efficient, objective and quantitative methods that capture entire spring groups and
complexes with sufficient detail to detect individual springs and vegetation health
Potential for wider application for mapping and monitoring other GDEs
Stream C – Potential Research Projects
a) The implementation of a multidisciplinary research program to survey the genetic
structure of spring based fauna and flora across the Basin to gain a better idea of
biodiversity and identifying potential ‘source’ populations
Management issue identified
by research & describe how
research will assist in managing
the issue.
Management issue is to conserve GAB biodiversity and
ecosystems. This research project will inform current
conservation priorities in the context of ongoing change.
The research would also:

Elaborate on evolutionary relationships

Degree of endemism

Estimate of gene flows to provide information on
effective ‘connectivity’

Overlaying information on other areas of research
– for example chemical processes, biogeography,
predicted changes in hydrological connectivity,
pressures.
b) Implementation and interpretation of advanced GAB modelling uncertainty to
prioritise locations for future field research.
Management issue identified
by research & describe how
research will assist in managing
the issue.
There are so many knowledge gaps and such little money;
we need a better method of prioritising fieldwork.
State the hypothesis, or the
idea or premise to be tested.
Specify the questions your
research will seek to answer.
How to prioritise fieldwork?
Research description including
literature review, field sampling
or survey, field or laboratory
experiments. Experimental
methodologies, sample size and
analysis tools.
GAB WRA 2013
AWMSGAB 2013
New conceptualisation is available but it’s only semiquantitative.
Fitting a modelling back-end to the new conceptualisation
- doesn’t have enough data to support it, but would yield
some areas where it can and can’t be constrained. This
can help direct where to place further attention for data
gathering.
Stakeholders to be consulted
GAB WRA and AWMSGAB teams. GABCC
Identify how the proposed
research relates to existing
research, particularly any crossdisciplinary connections
It would allow prioritisation to other research. Outputs of
the model (for example uncertainty), could be interpreted
for many purposes (for example hydrology, springs,
ecology)
Describe your research design,
including literature review, field
sampling or survey, field or
laboratory experiments. What
methodology will you use
throughout your project? How
will you identify your research
sample? How will you collect
and analyze data?
Desktop – PhD projects.
Include a rough cost estimate;
the cost estimate should
include people and resources
List any deliverables that are
related to the research
PhD scholarships
PhD thesis
Publications (for uncertainty analysis)
Framework model – could be populated and built up to a
working model later as more and more gaps get filled.
Knowledge Stream D – Higher value uses
Investment to introduce best practice water use into the pastoral industry has been
considerable as this industry uses the most GAB water. New water distribution
technologies have opened up opportunities for pastoralists and land managers, and
led to benefits across the Basin. Investment in best practice water use for other
industries within the GAB could yield further significant benefits and requires
investigation.
Stream D – Potential Research Projects
a) Expiration / Extinction risk of endemic GAB organisms at a Basin wide scale
Management issue identified
If communities cannot respond to a change then risk of
by research & describe how
species losses are higher. If endemics are sensitive to a
research will assist in managing change then extinction risks are higher.
the issue.
Hypothesis, idea or premise to
be tested by the research
question
Research description including
literature review, field
sampling or survey, field or
laboratory experiments.
Experimental methodologies,
sample size and analysis tools.
Springs endemics have a narrow tolerance
range/threshold. This tolerance range varies between
species. A change in flow, land use and introduced species
will affect spring habitats (for example water chemistry,
turbidity and flora)

Connectivity and dispersal studies (Murphy,
Worthington)

AWMSGAB reports
Knowledge Stream E – Valuing investment and allocation
Water from the GAB supports natural and cultural values and human activities. Additional
research is required to better value GAB resources, to develop comparative models for
industries and activities supported by GAB resources, and to assess the returns on
investment in water infrastructure. This will support future investment and management
decisions and build on the significant existing investment.
Stream E - Presentations
Groundwater chemistry, origin of spring water and
acid sulphate soil issues.







Water chemistry can help in understanding
flow
Relates to age of groundwater
There are changes to chemistry along flow
lines towards the discharge area.
Acid sulphate soils in mound spring are an
issue
Impact on fragile ecosystems
This does not generally occur widely
across the GA because of calcium
carbonate.
ASS problem when water levels decrease.
This has occurred in springs across the
GAB over relatively recent time (before
European arrival).
Mound Formation.



Towards a comprehensive database for the
GAB springs with an update on recent
progress in Queensland and New South
Wales.

Palaeo ecology.



Effective conservation and
management of cultural and
ecologically important environments
Terrestrial structures composed of
similar rock used elsewhere as data
sources for palaeoclimatic,
palaohydrological and neotechtonics
studies.
Modelling change in gross discharge
rate over time
Useful to prioritise the capping of
bores in close proximity to high value
springs
Mound springs untapped archive of info
about past climate
Understanding climate – past and future change and variability
Test models to see how well they model
past climate data.
South Australian perspective, including summaries of NWC project outcomes.


Real Time Kinematic Differential GPS provides accurate and repeatable measurement of spring
vent elevations
Spring Survey Provide a benchmark of spring status as of 2011. Spring inventory survey
consisted of:
o Flow, pH, Conductivity, Temperature
o Flora, Fauna
o Grazing, Pugging, Threats
o 1785 Springs had flow estimates collected; and
o 1055 vents had full inventory survey
Stream E – Potential Research Projects
b) Aggregation and collation of baseline data for socio-economic, cultural, hydrological
and ecological and hydrological disciplines
Management issue identified
by research & describe how
research will assist in managing
the issue.
Provision of baseline knowledge across all disciplines
which is able to be accessed via one portal. To better
inform planning, policy development and decision making.
Hypothesis, idea or premise to
be tested by the research
question
Having a consolidated baseline data set will allow sound
decisions for the management of the GAB
Stakeholders to be consulted
Government, Industry, pastoral, tourism and scientific
Identify how the proposed
research relates to existing
research, particularly any crossdisciplinary connections
The research project will cultivate cross-disciplinary
connections.
Research description including
literature review, field sampling
or survey, field or laboratory
experiments. Experimental
methodologies, sample size
and analysis tools.

Audit of data

Choose suitable interference

Identify gaps

Collect missing info

Add to database

Incorporate database update and maintenance
schedule
Include a rough cost estimate;
the cost estimate should
include people and resources
$10 million
List any deliverables that are
related to the research
Consolidated database for stakeholders and decision
makers in the GAB
Aggregated Forum Outcomes
A ranked list of the top 10 research priorities identified by Forum attendees is at Table 1.
Table 1 - Individual Research priorities as identified and ranked by Forum
participants
Comment
Rank
Vertical movement and Connectivity studies. Validate through measurement of
vertical leakage via remote sensing, polygonal faulting and further examination of
major structures
1
Palaeo studies - exploiting the potential to provide climate and environmental
histories, connectivity, taxa, connectivity and link to the effect of stressors and site
specific fluctuations
2
Establishment of a National, sharable, co-operative GAB database for risk
assessment and mitigation (ecology, hydrology, cultural) facilitating reliable data
access and storage
3
Development of conceptual models for Springs. Further understanding of the nature
and function of GAB Springs, including examination of “extinct” springs, back
4
forecasting, flow/stress relationships and geomorphology of springs
Quantification of the socio-economic benefits of the GAB, including its non-value
uses, cultural information & knowledge, fiscal information & Identification of
options for using co-produced water from CSG activities
5
Collection of baseline data regarding socio-economic conditions in areas of GAB that
are targeted for future resource development including ; a) demographics b) recent
history of community change c) community services d) local health statistics e)
education f) employment opportunities / patterns and g) small business, h)
recording GAB histories, I) changed farming practices & j) jurisdictional co-operation
6
Survey of Fauna Cultural and Heritage value of Springs and mapping and
Assessment of extinct springs (incl. spring tail survey)
7
Developing a hypothesis about ecology - hydrology relationships for broad spring /
GDE types on a regional scale. Improve understanding of hydro ecological
relationships with the aim of identifying driving hydrological variables associated
with indicators of ecological values.
8
Spring vent conduits: how does conductivity vary with time or in response to spring
flow rate changes?
9
Approaches to monitoring regarding springs, in particular a) what b) where c) how
d) best management approaches e) natural variability f) methods to deliver an
outcome g) spatial distribution
10
A ranked list of the top 7 potential research projects (1 being the highest ranked priority)
identified by mapping to individual research priorities attendees is at Table 2.
Table 2 - Proposed Research projects addressing top research priorities as
identified by Forum participants
Rank
Investigation of structural controls on groundwater flow (vertical and horizontal)
1
A portrait of the Rolling Downs Group – Understanding the Winton/Mackunda
Aquifer and underlying aquitard. A neglected aspect of the GAB; and
2
The response of spring systems to closure of a high flowing bore in South Australia
3
Undertake genetic structure of spring based fauna and flora (all biota impact)
across the basin to better understand biodiversity and to identify potential ‘source’
populations
4
Expiration/extinction risks of endemic GAB organisms at a Basin wide scale.
5
Using GAB modelling uncertainty to priorities future research areas.
6
Provision of baseline data for socio-economic, cultural, hydrological and ecological
and hydrological disciplines
7
The Fora successfully identified a diversity of GAB knowledge gaps and then focused upon
priority research needs. Table 1 describes a narrowed scope of high priority research needs.
Of those areas considered to be a high research priorities workshop subgroups delivered a
draft scope for research and knowledge projects to address the identified priority needs.
This is shown at Table 2.
Forum Conclusions
Forum attendees identified a handful of specific hydrogeological properties within the GAB
as being the highest priority for future research, within this selected group the highest
priority for future research being the absolute requirement to quantify the amount of
vertical leakage from GAB formations into overlying and underlying geological units.
Forum attendees provided an interim scope for a potential research project to assist with
the quantification of vertical leakage (See Potential Research Project 1A). As such this
potential project was proposed by Forum attendees as the highest priority potential
investment.
Forum attendees identified a secondary research priority being the need to further quantify
(through remote sensing and/or other methodologies) the influence of polygonal faulting on
leakages from GAB aquifers.
Attendees also flagged a number of ecological parameters within the GAB as priorities for
future research, with a key theme being the need to better understand and record
ecohydrological relationships and thresholds within the GAB
Appendix 1 – Raw Score and relative ranking of all research priorities identified by
Forum participants
Category
Comment
Score
Rank
Socio-economic
Quantification of the socio-economic benefits of the GAB, including its non-value uses
15
19
Identification of options for using co-produced water from CSG activities
14
20
Baseline data regarding socio-economic conditions in areas of GAB that are targeted for future resource development including ; a)
demographics b) recent history of community change c) community services d) local health statistics e) education f) employment opportunities
/ patterns and g) small business
24
14
Sectoral social and economic value of the GAB
13
21
Cultural knowledge and translation (and look for agreement in gaps)
22
16
fiscal evaluation of water in the GAB
27
12
Recording a GAB histories (Indigenous knowledge)
13
21
Talking to farmers about how they have changes their practices since bore capping - piping
1
30
Information sharing between jurisdictions
15
19
Assessment of how GABSI has changed farming practices
14
20
Assessment of the value and importance of GABSI for the pastoral industry
14
20
GABSI
Surveys
Intensive monitoring of the impact of the bore capping and piping program, ie flows to springs, leakage to unconfined aquifers etc
15
19
Fauna Surveys of QLD Springs Systems, incl spring tail survey
35
7
Cultural and Heritage value of Springs
12
22
Mapping and Assessment of extinct springs
13
21
Mapped spatial distribution of high leakage zones provides basis for improving regional water balance estimates and testing concept of
‘harvesting vertical leakage’.
15
19
AGM of Namoi and other paleochannels to look at connectivity
10
24
Current water usage/extraction in the GAB for management
15
19
Better characterise GAB LEB surface groundwater interactions
13
21
Spring vent conduits: how does conductivity vary with time or in response to spring flow rate changes?
26
13
Methods to map variability of flux, incl AEM
26
13
Connectivity of Alluvial systems
15
19
Improved potentiometry of the WM Aquifer
14
20
Development of standardised approach to applying corrections to flow direction calculations
12
22
Connectivity Studies - between systems (ie aquifers and aquitards, or springs and groundwater)
42
3
Connectivity between GAB and underlying Basins
36
6
Hydrogeology
Reactive transport hydrochemistry of coal seam gas water into other aquifers
14
20
Surface water / groundwater interaction studies with regard to a) natural connections and b) variability over time
15
19
Measuring upward leakage rates (inlc. Polygonal faults)
1
30
Need an improved knowledge of connectivity between coal measures and aquifers
1
30
Understand leakage mechanisms
13
21
118
1
Develop a standardised approach for applying corrections to flow direction calculations
1
30
Condamine connectivity
1
30
Hydrology of Walloons
1
30
Influence of structures upon flow within the basin and between the basin
1
30
Detailed understanding of aquifer responses to long term injection
2
30
Application of regional water balance estimates/models using new data.
30
9
Structural controls (for hydrology and ecology)
28
11
Influence of structure on lateral flows
14
20
Validate updated conceptual understanding
13
21
Remote sensing to detect and map the influence of polygonal faulting especially within the Rolling Downs Sequence
43
2
Potentiometry across major faults
24
14
Vertical movement – how much leakage. Validate through measurement of vertical leakage via remote sensing, polygonal faulting and major
structures
Establish aquifer geometry and characteristics, hydrochemistry and the mineralogy in the Rolling Down Group.
10
24
Vertical leakage in/out of J-aquifer
15
19
Developing an hypothesis about ecology - hydrology relationships for broad spring / GDE types on a regional scale to improve understanding of
hydro ecological relationships with the aim of identifying driving hydrological variables associated with indicators of ecological values
14
20
Common data repository
12
22
Establishment of a National GAB database
33
8
Establishment of a co-operative database for risk assessment and mitigation
20
18
Need for a National Data Base (ecology,hydrology,cultural)
16
Database
National database to extend to worlds springs database
1
30
Data access and storage
14
20
Reliable database for risk assessment
10
24
9
25
Co-operative government/industry/research community strategies
19
19
Develop policy and management strategies
11
23
1
30
Data sharing capability
Management
Need to re visit other management polices GAB
Monitoring
Approaches to monitoring regarding springs, in particular a) what b) where c) how d) best management approaches e) natural variability f)
methods to deliver an outcome
14
Extend time sequence of satellite record of wetlands back to 1980
15
Analyse time series date to identify the relative contributions of flows, climate and season
14
20
Apply knowledge of surface expression of springs to enhance understanding of sub-surface processes
13
21
Wider application of remote sensing processes for spring characterisation & use methodology to develop a concept/approach of 'envelope
characterisation'
12
22
1
30
Lack of adequate spatial distribution of monitoring data cohesive
21
17
Requirement for monitoring bores in the central part of the Basin
13
21
9
25
Multivariate analysis - how does this methodology contribute to assessment of EPBC issues
11
23
Define thresholds of change for impact assessment
10
24
Realistic drawdown surveys
12
22
6
28
link remote sensing capability with other disciplines/knowledge for enhanced understanding of springs – eg. evapotranspiration, diffuse
discharge, mound extent
20
Cmulative Impact
Cumulative impacts of water extraction
Analysis and Assessment
Modelling
Development of a local scale conceptual model
Is it sufficient to produce an updated version of GABTran transient model with complexities for future groundwater modelling?
1
30
Extent to which steady state models overestimate compared to transient models with regard changes in water level results
1
30
How useful are composite models of intensive use to model GAB water levels
1
30
More monitoring networks and systems
1
30
14
20
1
30
Scale issues, heterogeneity and upscaling
22
16
Modelling water pressure - knowledge gap
15
19
Cumulative impact of various demands on water resource, problematic to predict new impacts of current uses in light of proposed
development.
13
21
Better understanding of ET losses from springs or wetlands to inform variation in discharge - wetlands relationships
12
22
Springs conceptual models
14
20
With continuation of the bore capping program will new springs develop?
1
30
“extinct” springs may not be extinct
1
30
Further understanding of the nature and function of GAB Springs
1
30
Past is the key to predicting the future – palaeo studies of the system
1
30
Undertake optically stimulated luminescence dating to find out age of Warburton minor
1
30
Steady state versus transient models
Predictive capacity ("natural" vs "development")
Springs/Ecology
Replicate Phragmites results at other sites
1
30
Exploit the potential of other sites to provide climate and environmental histories of the springs themselves and their environment
1
30
Continuing research re relationship between springs
1
30
Future survey and monitoring using remote sensing
1
30
Ecohydrological relationships and thresholds
37
5
Spring complex water balance: how much water remains in the perched/confined aquifer surrounding the springs
13
21
Changes in spring flow in response to aquifer stress
26
13
Audit of existing current management of the Springs (ie how are springs management how?), and development of best management strategies
for springs
15
19
How to determine if impacts fall outside range of natural variation (ie establish baselines etc)
14
20
Develop effective quantitative methods for Gambiosia
29
10
Coordinate and compile basic geographic information on GAB Springs for public
28
11
Describe spring endemic species by molecular structure and morphology
13
21
Analyse and define associations of springs dependent species with physical spring characteristics
26
13
Back forecast spring extinction to define modelling capacity
11
23
Experimental manipulation of springs species to define habitat (water chemistry) association
10
24
can we make endemic spring habitat from bores
9
25
cap bores with priority for high value springs
8
26
extend biological understanding of salt scalds
7
27
the geomorphology of spring wetland types
6
28
compare traits of springs dependent and non-spring species
5
29
Understanding the source of spring water
11
23
Connectivity of fauna between springs
39
4
Understand basic tolerance of taxa to environmental factors
14
20
Basic community structure of springs, across complexes
28
11
Need for continuity and linking of approaches in Queensland and South Australia
15
19
Research on historical records for future monitoring of springs to assist with understanding the natural cycles of the springs
14
20
Understanding the effect of climate on surface expression of springs
13
21
Incorporation of test/control studies of impacts of different stressors on springs
10
24
Systemic mapping and conceptualisation of GDE's
27
12
Better understand resilience of flora/fauna
26
13
Causes of seasonal fluctuations in extent of some complexes at Edgbaston Springs
14
20
Better taxonomy
12
22
Understand adaptation mechanisms
23
15
Toad impacts on invertebrates from springs
13
21
Water Balance
Revise GAB water balance using updated understanding
15
19
Appendix 2 – Aggregate score and relative ranking of all research priorities
identified by Forum participants
Category
Comment
Score
Socio-economic
Quantification of the socio-economic benefits of the GAB, including its non-value uses, cultural information & knowledge, fiscal information &
Identification of options for using co-produced water from CSG activities
78
Baseline data regarding socio-economic conditions in areas of GAB that are targeted for future resource development including ; a)
demographics b) recent history of community change c) community services d) local health statistics e) education f) employment opportunities /
patterns and g) small business, h) recording GAB histories, I) changed farming practices & j) jurisdictional co-operation
66
Assessment of the value and importance of GABSI for the pastoral industry & how GABSI has changed farming practices
28
GABSI
Surveys / Monitoring
Intensive monitoring of the impact of the bore capping and piping program, ie flows to springs, leakage to unconfined aquifers, and current
water usage/extraction in the GAB for management
30
Survey of Fauna Cultural and Heritage value of Springs and mapping and Assessment of extinct springs (incl spring tail survey)
60
Mapped spatial distribution of high leakage zones provides basis for improving regional water balance estimates and testing concept of
‘harvesting vertical leakage’, including AGM of Namoi and other paleochannels to look at connectivity
25
Approaches to monitoring regarding springs, in particular a) what b) where c) how d) best management approaches e) natural variability f)
methods to deliver an outcome g) spatial distribution
48
Extend time sequence of satellite record of wetlands back to 1980 & analyse time series date to identify the relative contributions of flows,
15
Rank
climate and season
Apply knowledge of surface expression of springs to enhance understanding of sub-surface processes
13
Wider application of remote sensing processes for spring characterisation & use methodology to develop a concept/approach of 'envelope
characterisation' link remote sensing capability with other disciplines/knowledge for enhanced understanding of springs – e.g.
evapotranspiration, diffuse discharge, mound extent
13
Hydrogeology
Better characterise GAB LEB surface groundwater interactions including a) natural connections and b) variability over time c) connectivity with
coal aquifers and d) influence on lateral flows
43
Spring vent conduits: how does conductivity vary with time or in response to spring flow rate changes?
56
Methods to map variability of flux (incl. AEM), Measuring upward leakage rates (inlc. Polygonal faults),
42
Vertical movement/connectivity/structures/ potentiometry – how much leakage. Validate through measurement of vertical leakage via remote
sensing, polygonal faulting and major structures Connectivity Studies - between & within systems,
332
Development of standardised approach to applying corrections to flow direction calculations
13
Reactive transport hydrochemistry of coal seam gas water into other aquifers, understanding of aquifer responses to long term injection
16
Developing an hypothesis about ecology - hydrology relationships for broad spring / GDE types on a regional scale to improve understanding of
hydro ecological relationships with the aim of identifying driving hydrological variables associated with indicators of ecological values,
Application of regional water balance estimates/models using new data, validate updated conceptual understanding
57
Database
Establishment of a National, sharable, co-operative GAB database for risk assessment and mitigation (ecology, hydrology, cultural) for reliable
Data access and storage
Management
115
Co-operative government/industry/research community strategies
19
Develop policy and management strategies
12
Cumulative Impact
Cumulative impacts of water extraction
9
Analysis and Assessment
Multivariate analysis - how does this methodology contribute to assessment of EPBC issues
11
Define thresholds of change for impact assessment
10
Realistic drawdown surveys, knowledge gaps around modelling groundwater pressure & cumulative impact of various demands on water
resource
42
Modelling
Development of a local scale conceptual model
6
Is it sufficient to produce an updated version of GABTran transient model with complexities for future groundwater modelling? Extent to which
steady state models overestimate. How useful are composite models of intensive use
16
Scale issues, heterogeneity and upscaling. Predictive capacity ("natural" vs "development")
23
Better understanding of ET losses from springs or wetlands to inform variation in discharge - wetlands relationships, Spring complex water
balance: how much water remains in the perched/confined aquifer surrounding the springs
25
Springs conceptual models. Further understanding of the nature and function of GAB Springs s “extinct” springs may not be extinct, back
forecasting, ecology vs flow/stress relationships, geomorphology of springs
96
With continuation of the bore capping program will new springs develop? can we make endemic spring habitat from capping high value bores
47
Springs and Ecology
Palaeo studies of the system- exploiting the potential to provide climate and environmental histories, connectivity, taxa, connectivity, linkages
effect of stressors and site specific fluctuations
184
Undertake optically stimulated luminescence dating to find out age of Warburton minor
1
Replicate Phragmites results at other sites
1
Future survey and monitoring using remote sensing and audit of existing current management of the Springs
43
Ecohydrological relationships and thresholds & understanding the source of spring water
48
Better understand resilience of flora/fauna .How to determine if impacts fall outside range of natural variation (ie establish baselines etc)
28
Develop effective quantitative methods for Gambiosia
29
Coordinate and compile basic geographic information on GAB Springs for public
28
Describe spring endemic species by molecular structure and morphology
13
extend biological understanding of salt scalds
7
Toad impacts on invertebrates from springs
13
Revise GAB water balance using updated understanding
15
Water Balance
Appendix 2 GAB Forum Program
Appendix 3 – GAB FORUM PRESENTATION ABSTRACTS
Research Summary - Diffuse Discharge
Glenn Harrington
Diffuse groundwater discharge from the J-K aquifer on the western margin of the GAB
occurs by a combination of very slow upward leakage through massive sections of shale
aquitard and comparatively fast preferential flow along fractures and faults. Both
mechanisms discharge water into shallow phreatic aquifers. Using physical and
environmental tracer techniques, we have determined ranges of effective hydraulic
conductivities for these two mechanisms as 0.4×10-13 to 1.2×10-13 m/s and at least 1×10-9
to 1×10-8 m/s, respectively. The former range was derived from detailed vertical profiles of
pore-water pressure and chemistry, and relate to a discharge flux of about 3 mm per 10,000
years in two areas of gently undulating surface topography. In contrast, the latter range was
derived using helium-4 concentrations in shallow groundwater across a large spatial extent
of the western margin, often coincident with playa lakes. Thus surface topography appears
to be a useful proxy for groundwater discharge flux; while this may seem obvious in the
sense that playa lakes are local groundwater discharge zones, the suggestion that they may
also reflect preferential discharge of deep groundwater from the J-K aquifer warrants
further investigation as means of calculating diffuse discharge flux at a scale relevant for
water resources management.
GAB springs fish management and conservation: a case study from
Edgbaston, Queensland
Dr Adam Kerezsy
Bush Heritage Australia
The springs at Edgbaston in central western Queensland comprise the most ecologically
diverse Great Artesian Basin complex in Australia, and contain the only populations of the
iconic red-finned blue-eye – Australia’s smallest and rarest fish. The red-finned blue-eye is
listed as endangered under both Australian (EPBC) and Queensland legislation and as
critically endangered by the IUCN. In September 2012 the species was included in a book
published by the IUCN called Priceless or Worthless?, the aim of which was/is to raise
awareness of the plight of the 100 most endangered species worldwide.
In freshwater systems invasion by alien fish has a dramatic impact on native fish decline,
and the impacts associated with alien species are magnified in isolated aquatic ecosystems,
particularly in water-remote arid areas. As these impacts are most damaging in areas where
there is high endemicity of resident biota, the potential for species decline and loss is
therefore extremely high in isolated arid-zone aquatic ecosystems such as the Great
Artesian Basin spring complexes in inland Australia.
The red-finned blue-eye, Scaturiginichthys vermeilipinnis was discovered in 1990 by Peter
Unmack in spring-fed waters at Edgbaston station, north-east of the town of Aramac in
central western Queensland. Edgbaston is located in the semi-arid Thomson River
catchment which is part of the Lake Eyre Basin, and became a reserve in 2008 following
acquisition by the not-for-profit conservation organisation Bush Heritage Australia. The redfinned blue-eye is the only pseudomugilid fish known from inland Australia, with other blueeyes generally found in coastal draining rivers of northern and eastern Australia and New
Guinea. The red-finned blue-eye reaches a maximum length of 3cm and has only been
recorded from the spring complex at Edgbaston.
The Great Artesian Basin springs at Edgbaston are isolated aquatic ‘islands’ within a semiarid landscape. Currently there are up to 100 springs, soaks or damp areas present at
Edgbaston, and the amount of water within each spring ranges from moist areas or small
puddles to areas up to 30m wide. Despite variation in the extent of wetlands depending on
the moisture status of the substrate, water depth within the springs rarely exceeds 5cm due
to the flat landscape. Over long timeframes groundwater discharge to the springs may have
been diminished by water extraction through artesian bores. The springs contain slightly
saline water (generally up to 1mS/cm) that emerges, devoid of dissolved oxygen, at a
constant temperature of approximately 24°C from the spring vents. However, when the
water is distributed within the springs it becomes oxygenated and the temperature
fluctuates in relation to season and time of day (from close to freezing in winter to close to
40°C in summer).
Discharge springs such as the complex at Edgbaston have been identified as priority areas
for conservation in the central Australian arid and semi-arid zones using the criterion of
endemicity (Fensham et al. 2011), and the aquatic biota at Edgbaston is the most speciesrich of any spring complex in Australia as a result of the diversity of endemic fishes, plants
and invertebrates. In addition to red-finned blue-eye, the Edgbaston goby, Chlamydogobius
squamigenus, occurs in at least ten local springs and a large number of endemic aquatic
snail species from the hydrobiid, planorbid and bithyniid families are present (Ponder and
Clark 1990). Both the ecological community and extant individual species at Edgbaston have
been listed under endangered species legislation and are the subject of recovery plans (NCA
1992; EPBC 1999; Fensham et al. 2007, 2008).
Temporary floodwaters provide colonisation opportunities between the isolated springs for
all aquatic biota at Edgbaston, and this includes the alien fish eastern gambusia, Gambusia
holbrooki. Although the origin of eastern gambusia at Edgbaston is unknown, red-finned
blue-eye populations declined from seven to four springs between 1990 and 2007, with
colonisation of the springs by gambusia the most likely causal factor (Fairfax et al. 2007).
Gambusia have been demonstrated to have deleterious effects on native Australian
freshwater fish (Ivantsoff and Aarn 1999) and specifically on a related member of the
pseudomugilid family Pseudomugil signifer (Howe et al. 1997). Although the exact
mechanism(s) by which gambusia impact red-finned blue-eye is unknown, the recorded
patterns of local extirpation (in both Fairfax et al. 2007 and also more recently) indicate that
these events are always accompanied by gambusia infestation.
The threats to red-finned blue-eye - a naturally-restricted distribution combined with the
imposition of an invasive species - were recognised shortly after its discovery. Prior to being
listed as an endangered species it was raised in captivity and attempts were made to
establish translocated populations at Edgbaston (Fairfax et al. 2007). However, former
keepers and collectors of the species confirm that no captive populations have endured or
currently exist. Additonally, all translocations undertaken in the early 1990s (Wager 1994)
have failed, most probably due to colonisation by gambusia and/or drying of receiver
springs (A. Kerezsy, personal observations 2009 – present).
In recognition of the red-finned blue-eye extinction threat, Bush Heritage Australia began a
project in 2009 with the aims of investigating methods of controlling gambusia and
relocating populations of the endangered species. The piscicide rotenone was used to
evaluate its effectiveness for removing gambusia from selected springs, and small numbers
of red-finned blue-eye were relocated to ‘safe’ springs that were unlikely to be colonised by
gambusia. It was found that repeated applications of rotenone were necessary to remove
gambusia, and also that the application of the chemical did not have a deleterious effect on
non-target organisms (such as aquatic invertebrates). Similarly, relocation of red-finned
blue-eye was generally successful, and in most instances self-sustaining populations
eventuated from small founder populations (~20). Combining the two techniques (gambusia
removal and red-finned blue-eye relocation) and expanding the project to include other
techniques such as barrier construction around springs and the establishment of captive
populations should be pursued in order to prevent the species becoming extinct.
In this talk, results from the initial phase of the project are presented, and the future of the
project is discussed with reference to factors that are likely to impact upon its
implementation and success.
Evaluating Risks to Great Artesian Basin Springs.
Graham Green
Over much of the area underlain by the Great Artesian Basin (GAB), groundwater provides
the only reliable source of fresh water for all human activity, including the pastoral, mining
and tourism industries, as well as outback towns. Hence, while the GAB springs have great
ecological and cultural value, the utility of the region‘s groundwater results in a number of
competing interests that threaten the springs and the health of their attendant ecosystems.
With thousands of springs of varying ecological value and vulnerability, natural resource
managers require an assessment system that facilitates the prioritisation of mitigation and
remediation efforts.
As a component of the NWI project Allocating Water and Maintaining Springs in the Great
Artesian Basin, a risk assessment process has been developed to analyse and evaluate risk
factors associated with reductions in groundwater pressure in the GAB. Methods for the
evaluation of risks are presented that enable the assessment of:

Reductions in spring flow rates in response to aquifer drawdown

Vulnerability of springs to various impacts resulting from a reduction in spring flow
rate

Values of spring ecosystems according to a range of key ecological value criteria.
To enable risk assessment of such complex environmental assets, a multi-stage process is
presented that facilitates:

Classification of springs and spring groups according to their morphological types

Identification of the degree of threats presented by proposed groundwater
developments and the likely impacts on spring flow rates

Assessment of the vulnerabilities of springs and spring groups to identified threats
according to their typology and degree of exposure to the threat

Assessment of the specific ecological values of springs and spring groups

A system of ratings for the likelihood of impacts arising, the specific vulnerabilities of
springs and specific ecological values of their ecosystems

A simple visual summary of the overall assessment outcomes and the ratings applied

Assessment of the controls, either existing or necessary, to mitigate assessed risks

Acknowledgement of uncertainties in the risk evaluation process and
recommendations for further information required to reduce uncertainties.

The risk assessment process is informed and underpinned by sound scientific
understanding of the ecological and physical characteristics of springs and the
response of these to identified threats. It brings together the most up–to–date
understanding of the nature and hydrogeology of GAB springs, including their
physical, hydrological, chemical and ecological vulnerabilities, and ecological values.
For example, the process for the assessment of the likelihood of impacts to the
springs makes use of new information provided for the first time by the outcomes of
this project, including the potentiometric surface map of the main GAB aquifer and
accurately surveyed elevations of the GAB springs in South Australia.

The risk assessment process culminates in a summary table displaying individual
assessments of the various risk components, the overall level of risk presented to the
subject spring or spring group, and indicating which risk components are considered
to be contributing the majority of overall risk. It is not recommended that an overall
risk ranking or single risk value is derived from the combination of risk ratings.
Rather, the risk assessment summary table provides a transparent account of each
risk component in order to guide informed decisions regarding appropriate risk
mitigation strategies.

The risk assessment process will primarily apply to springs that are within the parts
of the GAB where groundwater is under artesian pressure – where groundwater
hydraulic head elevation is higher than ground surface level, and the process is most
applicable where the level of data available meets the standard that currently exists
for the South Australian and Northern Territory parts of the GAB. However the
process is intended to be adaptable for application to springs throughout the GAB,
including non-artesian parts of the basin.
GAB Recharge – SA
Diffuse recharge & mountain system recharge along the western margin of
the GAB
Daniel Wohling
The major findings of our recharge studies along the western margin of the GAB are that 1)
modern day recharge is significantly less than discharge and therefore the GAB groundwater
system is not in hydraulic equilibrium, 2) the majority of recharge occurred during wetter
periods during the Pleistocene, 3) there has been virtually zero recharge for the past 10 000
years and 4) groundwater pressure levels are in a state of natural decline. These findings
highlight the importance of effectively managing the resource.
Understanding recharge mechanisms and estimating recharge rates in arid regions can
prove difficult and complicated due to large spatial and temporal variability of water fluxes.
This talk discusses the role of diffuse recharge and mountain system recharge along the
western margin of the GAB. Diffuse recharge can be described as recharge that enters the
water table as a result of the infiltration of precipitation and subsequent drainage that
occurs uniformly across the landscape (Scanlon et al. 2003). Mountain system recharge is
the contribution of mountain regions to the recharge of adjacent aquifers (Wilson & Guan
2004). Ephemeral river recharge – a form of localised recharge resulting from the addition
of surface water through stream, river or lake beds to the water table - is not discussed in
detail here. The potential for ephemeral river recharge to the J aquifer within South
Australia is limited. Tertiary sediments and/or Cretaceous Bulldog Shale overlie the J aquifer
along the Stevenson Creek and Alberga River restricting direct recharge. Furthermore,
radiocarbon dating of groundwater sourced from the J aquifer in proximity to the Alberga
River indicates that there is no active recharge occurring.
The study indicated that mountain system recharge mechanisms have been in operation in
the past and are likely to still be in operation. Specifically, hydrogeochemical data,
environmental tracers, hydraulic data and rainfall records identified that recharge to the J
aquifer has occurred to the east of the Peake and Denison Inlier and at Marla, and to the P
aquifer along the western flank of the Peake and Denison Inlier.
By the utilisation of multiple techniques to ascertain diffuse recharge rate estimates, the
study ultimately improved the understanding of diffuse recharge mechanisms along the
western margin of the GAB and consequently improved the conceptual understanding of
the system. Within this study, the areas where diffuse recharge mechanisms to the J aquifer
operate were redefined to include zones not previously mapped. Techniques used to assess
recharge across these areas provided very low estimates, typically less than 1 mm/year with
a mean of ~ 0.15 mm/year. In addition, the study revealed that deep unsaturated zone soil
profiles have mean pore water residence times in the order of 45 000 years. Furthermore,
the unsaturated core profiles imply the potential for downward and upward fluxes providing
a temporal context to diffuse recharge and suggesting steady state assumptions may not
accurately describe the processes occurring at these locations.
Scanlon, BR, Keese, K, Reedy, RC, Simunek, J & Andraski, BJ 2003, 'Variations in flow and transport in
thick desert vadose zones in response to paleoclimatic forcing (0-90 kyr): Field measurements,
modelling and uncertainties', Water Resources Research, vol. 39, no. 7, p. 1179,
DOI10.1029/2002WR001604
Wilson, JL & Guan, H 2004, 'Mountain-block hydrology and mountain front recharge', in:
Groundwater Recharge in a Desert Environment– The Southwestern United States, Water Science
and Application, Hogan, JF, Phillips, FM & Scanlon, BR (eds.), American Geophysical Union,
Washington.
Management and Monitoring of springs in the Surat CMA
Steve Fluke
In Queensland, the Coal Seam Gas (CSG) industry is rapidly expanding in the Surat and
Bowen basins. Developing a CSG production field involves pumping water from the coal
seams to release the gas adsorbed to coal particles. The reduction in water pressure in the
coal seams will cause a reduction in water pressure in overlying and underlying aquifers
because there is always some interconnectivity between formations.
The Surat Basin of the Great Artesian Basin supports a range of values including
environmentally and culturally significant springs. Potential impacts on these unique
ecosystems include both pressure related threats, caused by groundwater extraction
activities and non-pressure related threats, such as impacts from feral animals, grazing and
land management practices.
Under the Queensland regulatory framework the role of the Office of Groundwater Impact
Assessment (OGIA) is to predict impacts on groundwater levels in areas of intensive CSG
development and to publish the predictions and required management arrangements in an
Underground Water Impact Report (UWIR).
In October 2012, an UWIR was finalised for the Surat Cumulative Management Area. In
addition to outlining the predicted groundwater impacts from petroleum and CSG
development, the UWIR also provides integrated arrangements for monitoring changes in
aquifer water levels and at springs.
The UWIR includes a Spring Impact Management Strategy. The strategy shows the location
of springs in the area and describes their nature; the studies undertaken to inform the
development of management arrangements set out in the UWIR; specifies the spring
monitoring requirements for petroleum tenure holders; and specifies a path to the
development of mitigation actions by responsible tenure holders.
The UWIR also identifies key research themes to support the review of the UWIR in three
years time. One of the themes relates to spring research.
Managing the predicted impacts on springs
The management of groundwater impacts on springs involves understanding the magnitude
of impacts on underlying aquifers; the connectivity between the spring and underlying
aquifers; and the ecological and cultural values associated with the spring that may be
impacted by changes in groundwater conditions.
A range of assessments were undertaken to inform the understanding about springs and the
potential for groundwater impacts. These assessments underpin the management
arrangements established in the UWIR. Predictions from the regional groundwater model,
knowledge acquired through spring surveys and connectivity assessments provided the
basis for the integrated management arrangements.
Based on the assessments, five spring sites (38 spring vents) are expected to experience
impacts of greater than 0.2 metres in their source aquifers at some time in the future as a
result of planned CSG development. The maximum impact is predicted to be 1.3 metres.
Under the UWIR, these sites are identified for ongoing monitoring, further investigation and
development of prevention or mitigation actions. The mitigation actions could include
reduction in existing groundwater extraction through substitution of supplies or relocation
of extraction or direct actions. Responsibility for developing these mitigation plans is a
responsibility of petroleum tenure holders specified in the UWIR.
The UWIR also assigns to tenure holders responsibilities to monitor a wider set of springs.
Enhancing existing knowledge
In addition to the actions that will be carried out by tenure holders, OGIA will lead,
coordinate and facilitate research that will improve knowledge about the risk to springs.
Outcomes of that research will support future updating of the Surat UWIR and more
broadly, contribute to scientific outcomes that may be applied to springs in other areas.
Four key projects will be completed by late 2014.

Classify the hydrogeological settings of spring vents;

Confirm and identify watercourse springs;

Improve the efficiency and effectiveness of spring monitoring; and

Improve knowledge about the cultural heritage values of springs.
Summary
The presentation will summarise the spring sites, assessments and knowledge gained during
the development of the UWIR. It will describe the obligations that petroleum tenure holders
have under the UWIR in relation to springs. It will then describe the research activities that
OGIA is currently carrying out in relation to springs.
Interconnectivity Within the Surat CMA
In Queensland Coal Seam Gas (CSG) industry is expanding rapidly in the Surat and Bowen
basins. CSG production involves pumping water from the coal seams to release the gas
adsorbed to coal particles. The reduction is water pressure in the coal seams will cause
some reductions in water pressure in overlying and underlying aquifers because there will
always be some interconnectivity between the formations. The Surat Basin is a sub-basin of
the Great Artesian Basin which contains aquifers of high economic, environmental and
cultural value. The Condamine Alluvium is also an important water resource that overlies
parts of the eastern margin of the Surat Basin.
Under the Queensland regulatory framework the Office of Groundwater Impact Assessment
(OGIA) predicts impact on groundwater levels in areas of intensive CSG development and
publishes the predictions and required management arrangements in Underground Water
Impact Reports.
The Surat Underground Water Impact Report (UWIR) was approved in December 2012. It
described the following areas of particular significance with regard to interconnectivity
between aquifers.



The Walloon Coal Measures form a significant proportion of the base of the
Condamine Alluvium. The extent of interconnectivity is controlled by low
permeability materials at the base of the alluvial sequence and at the top of the
Walloon Coal Measures. The thickness of the low permeability layer is highly
variable.
Over a significant area the Walloon Coal Measures are in direct contact with the
overlying Springbok and underlying Hutton Sandstone. The extent of
interconnectivity is controlled by the relatively low permeability of the upper and
lower horizons of the Walloon Coal Measures which bound the gas producing
horizons. While the lower bounding horizon is relatively uniform, the upper horizon
is less so.
In the area north east of Roma the Precipice Sandstone of the Surat Basin is in direct
contact with the Bandanna Formation which is the gas bearing formation of the
Bowen Basin.
To prepare the Surat UWIR a regional groundwater flow model was constructed to make
predictions about the impact of planned CSG production. The model was based on current
understandings of the hydrogeology of the groundwater flow system. The regulatory
framework requires that the UWIR be updated every three years to incorporate new
knowledge about the behaviour of the groundwater flow system and planned CSG
development.
Accordingly, the UWIR identified six research themes that OGIA will pursue in preparation
for the updating of the UWIR. Several of these research themes relate to connectivity. The
OGIA approach to research activity is to collaborate and coordinate with other research
bodies, and then carry out additional research where necessary. Specific focus areas in
relation to interconnectivity are as follows.
Walloon / Condamine Interconnectivity
Although the induced leakage form the Condamine Alluvium into the underlying Walloons is
predicted to be relatively small, the alluvium is an economically important aquifer that is
already heavily stressed through agricultural development. It is important to build on the
current understanding of connectivity. The areas of research activity currently being
progressed by OGIA in collaboration with industry and research partners are as follows:



Field Studies: New monitoring bores will be installed and used to assess flow across
the alluvium / coal measure contact, in response to pump testing. Water level
measurements, and sampling for geochemical studies will be carried out at a whole
of system scale as well as in association with the pump testing. The drilling and pump
testing will be carried out by petroleum gas companies with close OGIA involvement.
Other aspects of the field studies will be carried out by OGIA in collaboration with
other research partners.
Conceptualisation: Historic hydrological data will be reassessed along with emerging
data from field studies to arrive at possible hydrogeological realisations of the
Condamine / Walloon Coal Measure interconnection.
Local Modelling: OGIA is constructing a local scale model which will be used to test
hypotheses in relation to interconnectivity.
Walloon / Hutton / Springbok Interconnectivity
Although falls in water pressure in the Hutton and Springbok Standstones in the area of
likely impact do not pose widespread threats to bore water supplies from these aquifers,
the area is extensive and it is important to build on current understanding of connectivity.
Additional physical and geochemical data will be collected in collaboration with research
partners to improve understanding of the distribution and the nature of the aquitards that
separate the coal measures from the overlying and underlying aquifers.
Synthesis
Learnings from the interconnectivity projects will enable an improved conceptualisation of
the whole of the regional groundwater system, which will support the construction of the
next generation of the regional groundwater flow model that will be the basis for the
revision of the Surat UWIR in late 2015.
The evolution and biogeographic history of the endemic invertebrate
community inhabiting South Australian mound springs
Nick Murphy1 Michelle Guzik 2
1.
Department of Genetics, School of Molecular Science, La Trobe University, Bundoora
Victoria, Australia.
2. Australian Centre for Evolutionary Biology and Biodiversity, School of Earth and
Environmental Science, The University of Adelaide, South Australia, Australia.
The Great Artesian Basin (GAB) springs are an area of rich endemism in Australia, especially
given the fragmented size and location of these arid zone habitats. The GAB springs habitat
as a whole is federally recognised as a biologically, culturally and hydrogeologically unique
region. The endemic flora and fauna that inhabit the springs are considered relicts from a
time when arid Australia was ‘warm and wet’ and are also likely indicators of spring health.
These springs have long held a fascination for biologists. They provide a relictual
environment for a suite of endemic species, genera and subfamilies of crustaceans, snails,
insects and plants. This talk presents the findings of six years of research examining the
evolutionary origins, distributions and population structure of the endemic aquatic
invertebrates. Significantly this research has increased the number of endemic arthropod
species from 3 to potentially 25 some of which occupy single springs. The phylogenetic
history of these species reveals that many have evolved prior to the formation of the springs
and has identified clear community-level patterns in biogeographic history, which can be
used to better manage this ecosystem. Fine scale genetic patterns reveal that population
structure and dispersal is species specific, and also likely to be location specific – an
important consideration for ongoing spring management.
There are three key points from the results of these studies to consider for the ongoing
management of spring biodiversity.
1. Spring complexes are currently the most appropriate level for the management of
endemic species.
Genetic variation between spring complexes is generally too high
for a general model of spring management, with most species restricted to single
spring complexes. However more detailed research is required
to adequately assess
gene flow and relationships between springs groups within a complex and among
springs within a group as evidence suggests that a number of species show a very
fine scale of genetic divergence – and that dispersal rarely occurs across the desert –
meaning that springs that cease to flow are unlikely to repopulate easily.
2. A large number of species are vulnerable due the fact they are restricted to single
spring groups, and in one case a single spring. Importantly many of these species are
not currently in protected land, and a number exist in springs that are quite
degraded.
3. Finally, there are many spring groups that deserve special consideration due to the
high number of endemic species that they harbour.
This study has revealed a number of important questions that are still to be answered. For
example;




Dispersal pathways between springs are still unclear – preliminary studies suggest
that direct connectivity between springs is important, meaning that spring flow is
critical for ongoing population persistence. Surface stream channels may also be
important for dispersal, however the role of long distance dispersal in establishing
new populations and maintaining present diversity is unknown.
Local adaptation to the specific groundwater conditions of an individual spring group
is likely to play a strong role in shaping the distribution of species – making it unlikely
that species can survive in springs other than where they presently persist.
It is likely that habitat characteristics, such as the number of interconnected springs,
the size of spring wetlands and the type of vegetation have a significant on species
inhabiting springs.
Importantly, the health of species with very small distributions (ie single springs) in
the face of habitat degradation, invasive species and reduced flow, is currently
unclear. These species are irreplaceable, and the role of these taxa in recycling
nutrients means extinction of any species may lead to the loss of other taxa.
It should be noted that this study has been undertaken on the Lake Eyre supergroup of
desert springs. The variability in population structure, genetic diversity and evolutionary
history across the Lake Eyre Springs and the differences amongst the species studied mean
that the results of this study can’t be translated across systems or taxa. Instead it appears
that species specific and location specific factors will play a role in structuring GAB spring
communities. Thus further research is required and is currently being undertaken across the
GAB springs to attempt to understand this ecosystem in order to properly understand and
manage this unique ecosystem.
Groundwater dependent ecosystems – mapping in the Qld GAB
Bruce Wilson, Mike Ronan & Moya Tomlinson
This paper outlines a proposal to map Groundwater Dependent Ecosystems (GDEs) in the
Queensland part of the Great Artesian Basin (GAB). The primary aims of this mapping are to
identify where these ecosystems occur and the extent and nature of their dependence on
groundwater at a scale that is appropriate for use in regional assessment and management
processes. The classification and methods to be used were developed during a project that
mapped the GDEs in the eastern Murray-Darling Basin and Burnett regions of Queensland
(DSITIA, 2012).
GDEs are defined as "ecosystems which require access to groundwater on a permanent or
intermittent basis to meet all or some of their water requirements so as to maintain their
communities of plants and animals, ecological processes and ecosystem services"
(Richardson et al. 2011). At the highest level there are three classes of GDEs in Queensland
mapping (modified from Eamus et al. 2006): 1) surface expression of groundwater (Surface
Expression GDEs) which includes GAB “springs”; 2) ecosystems dependent on the subsurface presence of groundwater (Terrestrial GDEs); and 3) aquifer and cave ecosystems
(Subterranean GDEs).
The mapping and classification method used in Queensland includes a number of steps and
stages. Firstly existing information is compiled and used as a focal point for a “walking the
landscape” (EHP, 2012a) workshop. This workshop is a consultative process with the full
range of stakeholders with an interest in GDEs including hydrologists, ecologists, geologists,
land managers and planners. During the workshop the landscape is systematically assessed
by the stakeholders to gain a common understanding of groundwater features and
processes. Expert knowledge about GDEs across the landscape is then elicited and collated
and used to identify datasets and rules to map the identified known and potential GDEs.
After the workshop the mapping rules are applied to the best available spatial data to
delineate areas that are likely to be groundwater dependent. The resulting conceptual
models, mapping rules and maps are used to develop hypotheses to guide field
investigations and further research. This leads to an iterative refinement of the information
and mapping often in collaboration with original workshop participants. The final stages of
the method include final feedback from user groups before finalisation of all products and
their release.
The Queensland GDE mapping integrates with existing mapping, particularly the regional
ecosystem (Neldner et al. 2012) and wetland (EPA, 2009), programmes so it can be
maintained and updated into the future. Other datasets that may be integrated using the
mapping rules include groundwater level data, geology, drainage lines, point locations of
GDE features, DEMs, and remotely sensed products. The proposed GAB mapping will
include ecological inventory as well as assessments of physical parameters.
The development of the pictorial conceptual models (EHP, 2012b) has proved to be an
important part of the mapping method for a number of reasons. They enable an often
diverse range of stakeholders to develop a common understanding and terminology about
the GDE features and then provide a means of assessing the data requirements and rules
(models) to map them. The models collate valuable supporting information to improve
understanding of the landscape processes that produce GDEs, the broader context and
function of GDEs, and assist in the estimation of GDE extent delineated in the GDE mapping.
It is expected these models will be updated over time as new information is collected and
increased understanding is gained.
All the maps, conceptual models, mapping rules and other information developed through
the Queensland GDE mapping programme are made available to the public on the
WetlandInfo website (wetlandinfo.ehp.qld.gov.au). For the Queensland GAB project this
information will be consistent with basin wide (e.g. South Australia) data sets to enable
national, state and regional decision makers to access relevant knowledge that will assist in
managing water resources with consideration of the ecological requirements of key
environmental assets.
Bibliography
DSITIA. (2012) Groundwater Dependent Ecosystem Mapping and Classification Method: a method for
providing baseline mapping and classification of groundwater dependent ecosystems in Queensland.
DSITIA, Brisbane [Available online March 2012 - wetlandinfo.ehp.qld.gov.au]
EHP (2012a) Walking the landscape—A whole-of-system framework for understanding and mapping
environmental processes and values, 6pp, Queensland Wetlands Program, Queensland Government,
Brisbane.[URL: http://wetlandinfo.ehp.qld.gov.au/resources/static/pdf/resources/walking-thelandscape-24-01-13.pdf]
EHP (2012b) Pictures worth a thousand words: A guide to pictorial conceptual modelling, Queensland
Wetlands Program, Queensland Government, Brisbane. [URL:
http://wetlandinfo.ehp.qld.gov.au/wetlands/Whatyoullfind/Whatyoullfind20130202.html]
Eamus, D., Froend, R., Hose, G., Loomes, R. and Murray, B. 2006, A functional methodology for
determining the groundwater regime needed to maintain health of groundwater dependent
vegetation. Australian Journal of Botany 54: 97-114.
EPA (2005) Wetland Mapping and Classification Methodology – Overall Framework – A Method to
Provide Baseline Mapping and Classification for Wetlands in Queensland, Version 1.2, Queensland
Government, Brisbane. [URL:
http://wetlandinfo.derm.qld.gov.au/wetlands/MappingFandD/WetlandMandDBackground.html]
Neldner, V.J., Wilson, B.A., Thompson, E.J. and Dillewaard, H.A. (2012) Methodology for Survey and
Mapping of Regional Ecosystems and Vegetation Communities in Queensland. Version 3.2. Updated
August 2012. Queensland Herbarium, DSITIA, Brisbane. 124 pp. [URL:
http://www.ehp.qld.gov.au/plants/herbarium/publications/pdf/herbarium_mapping_methodology.
pdf]
Richardson, E., Irvine, E., Froend, R., Book, P., Barber, S. & Bonneville, B. (2011), Australian
groundwater dependent ecosystems toolbox part 1: assessment framework, National Water
Commission, Canberra.
“Towards a comprehensive database for the GAB springs with an update on recent progress in
Queensland and New South Wales”
After 20 years since the initial surveys in Queensland nd New South Wales, another round of survey
has been conducted. These surveys will be compiled in a comprehensive database with the objective
of compiling data in a consistent format from all of the springs in the GAB. The nature of this
database will be described and other lessons from our experiences in Queensland will be presented.
Remote sensing: advanced mapping and monitoring techniques for spring
management
Assoc. Prof Megan Lewis and Dr Davina White
The University of Adelaide, South Australia
Introduction
Remote sensing scientists at the University of Adelaide have developed new methodologies
and protocols for mapping and monitoring the surface characteristics of the western margin
Great Artesian Basin (GAB) springs. A complementary suite of the latest state-of-the-art
remotely sensed imagery from satellite and airborne sensors was captured to determine the
spatial, temporal, and spectral characteristics of the GAB springs in South Australia. Field
protocols were developed and implemented to provide on-ground calibration of the image
outputs and assist in image interpretation. This approach was particularly useful for
establishing quantitative measures of wetland vegetation extent, distribution of dominant
vegetation communities and establishing a relationship between groundwater outflow and
wetland vegetation extent (Lewis et al., 2013). Moreover, a remote sensing approach using
coincident image and on-ground data collection provides meaningful quantitative results for
natural resource managers, which are rigorous, repeatable and scientifically valid. This
approach enables quantitative comparison of vegetation over time as well as at different
locations and settings. The outputs from the image analysis and allied field protocols
provide new insights into the response of vegetation to the flow of groundwater from the
GAB and to identify potential impacts of water extractions.
Key findings
Moderate Resolution Imaging Spectrometer (MODIS) hyper-temporal satellite imagery was
used in the form of Normalised Difference Vegetation Index (NDVI) 16-day composites, from
2000 to 2010/2011. These data successfully determined the inter-annual and seasonal
variability of growth responses of the dominant wetland vegetation types (such as
Phragmites australis and Melaleuca glomerata) relating them to climatic influences. In
addition GAB spring wetland vegetation was discriminated from the surrounding arid, saline,
upland and ephemeral riverine ecosystems. Longer term trends in the spatial and temporal
dynamics of Dalhousie and Hermit Hill Spring Complexes were also identified using MODIS
imagery time traces, which provided insights into the influence of rainfall on the wetlands
(Petus et al., in review).
Very high spatial resolution multispectral QuickBird and WorldView-2 satellite images were
used to establish a calibrated relationship between spring wetland vegetation extent and
surface spring flows associated with changes in aquifer pressure. Image NDVI was computed
and a threshold determined from the calibration relationship with on-ground vegetation
cover, which enabled precise quantitative delineation of the extent of the GAB spring
wetlands (White and Lewis, 2011). This high spatial resolution imagery, which covers
extensive areas of the landscape in detail, was particularly useful at providing a permanent
baseline record of the current status of the GAB spring wetlands at a range of scales from
individual springs and spring groups up to entire spring complexes. This approach was
successfully applied to a diverse range of spring settings, varying in their extent, distribution
and surface expression (Dalhousie, Mt Denison and Hermit Hill Spring Complexes). Changes
over time in the wetlands as a response to rainfall, ecological processes, and spring flow
were also quantified at an unprecedented level of detail.
Airborne hyperspectral imagery and precise on-ground RTK DGPS surveys were used to
characterise the surface expression of several major spring groups and complexes
(Dalhousie, Francis Swamp, Freeling and Hermit Hill). Hyperspectral imagery provides rich
spectral detail (many narrow wavebands) enabling discrimination of different vegetation
communities and types, as well as surface water, minerals, and substrate surface
expressions, which were found to have unique spectral characteristics that could be
differentiated at the spring group and complex scale. Tasked image captures with
concurrent on-ground validation data were collected and analysed to determine
geomorphic setting and terrain, spring vent distribution and flow status, distribution and
extent of wetland vegetation and dominant wetland vegetation species, zones of nearsurface moisture (wetted areas) and surface salinisation (associated with diffuse
evaporative discharge of groundwater), as well as change in these characteristics over time.
A number of advanced hyperspectral and multispectral remote sensing analyses (waveband
indices and spectral filtering and matching) were conducted to accurately delineate the
spatial distribution and extent of these spring characteristics within the arid landscape
(Lewis et al., 2013).
The hyperspectral analyses revealed wide-ranging characteristics of the four distinctly
different spring groups and complexes. This provided rich new baseline information such as
vegetation extent, distribution and composition, as well as associated saline surface
expressions and surrounding geomorphic landscape setting. Of particular note is the floristic
diversity and variability in spring vegetation composition, as well as differences in the
geomorphic setting and terrain between sites. Although these spring complexes and groups
each have a distinctive character, the hyperspectral analyses revealed some constants
across the spring environments. Zones of high surface moisture and diffuse discharge are
present at all springs, extending beyond the vegetated spring-fed wetlands. Phragmites
australis is present across all spring groups, although its abundance varies from site to site.
Where present, it is always in proximity to spring vents and on out-flowing tails. The
monitoring over time revealed the dynamic response of springs to climatic conditions, in
particular responses to unseasonally high rainfall events following several years of drought.
Management implications and recommendations
Ongoing monitoring using MODIS satellite imagery of wetland area as an indicator of spring
ecosystem status is required and needs to acknowledge the strong influence of season and
preceding rainfall on extent and greenness of the wetlands. Definition of baseline conditions
for larger extent GAB springs must incorporate the seasonal variations and longer term
trends identified in this study. The new understanding of spring temporal dynamics has clear
benefits for monitoring programs: it establishes the range of natural variation over time,
providing objective information of past and current status for interpreting future changes to
these sensitive environments, and could be used to define warning thresholds of extreme
change.
The very high spatial resolution satellite imagery captured the natural range of variation in
the wetland area spring flow relationship under different climatic conditions at the
Dalhousie Springs Complex. The generality of these findings was extended by establishment
of a similar relationship at Mt Denison Complex and Hermit Hill Complex, which both exhibit
quite different geomorphic and hydrologic contexts and a much smaller and interconnected
range of spring flows.
These relationships are very significant, as they confirm widely-held assumptions and the
underlying premise that wetland area is an indicator of spring flow. Measurements of
wetland area for individual springs can provide a surrogate for in-situ flow records that are
often difficult to obtain and maintain over time, given their disparate nature within this
remote, arid landscape. The remote sensing techniques developed and demonstrated in this
study provide an objective, repeatable and cost-effective means of estimating and
monitoring changes in spring flow.
Hyperspectral image analysis provided the first thorough documentation and quantitative
baseline mapping of the geomorphic context and surface expression of the GAB springs,
their associated wetlands and environments. This included high-resolution definition of the
spatial extent and distribution of wetland vegetation, selected dominant vegetation species,
and surrounding zones of high surface moisture and diffuse evaporative discharge. This new
understanding of the spring environments provides valuable information for future
ecological studies and assessments of conservation status.
References
Lewis, M.M., White, D.C. & Gotch, T.G. (Eds.). Allocating Water and Maintaining Springs of the
Western Great Artesian Basin. Volume VI. Spatial Survey and Remote Sensing of Artesian Springs of
the Western Great Artesian Basin. National Water Commission, Canberra (In press).
Petus, C., Lewis, M.M. and White, D.C. Monitoring temporal dynamics of wetland vegetation at
Dalhousie Springs Complex in Australia using MODIS Normalized Difference Vegetation Index.
Ecological Indicators (In review).
White, D. and Lewis, M. (2011). A new approach to monitoring spatial distribution and dynamics
of wetlands and associated flows of Australian Great Artesian Basin springs using QuickBird satellite
imagery. J. Hydrology 48:140-152.
Upwards leakage around the southwestern margin of the GAB
Justin Costelloe
This project used field measurements and remote sensing techniques to quantify, with greater
confidence, the component of near surface, vertical leakage around the southwestern margin of the
Great Artesian Basin (GAB) in South Australia. The following outcomes were produced:
1. A conceptual model was developed that classified discharge zones into broad categories
based on their depth to water table and expected surface characteristics. These surface
characteristics were mapped using remote sensing data and the zones were assigned ranges
of evaporative discharge estimated from field measurements. The project measured rates of
discharge ranging from 0.2 mm y-1 to 542 mm y-1.
2. Discharge rates of >100 mm y-1 generally occurred in areas with shallow groundwater (<1 m
depth), moist soils and typically with salt precipitation at the surface (the ‘Liquid Transport
Zone (LTZ)’ of the conceptual model). The LTZ occurred around and/or along strike of springs
and was assigned a range of 100-300 mm y-1 for use in the estimates of evaporative
discharge.
3. Discharge areas with moderately dry surface soils but with the presence of some visible salt
precipitation or ‘crusty’ soil surface textures, corresponded to the Mixed Transport Zone
(MTZ) of the conceptual model. These areas coincided with groundwater table depths of 1.33.7 m and in many cases the MTZ surrounded areas of LTZ. The MTZ was assigned a range of
10-100 mm y-1 for use in the estimates of evaporative discharge.
4. The area surrounding the higher discharge zones (i.e. LTZ and MTZ) typically had dry surface
soils and no visible salt precipitation at the surface. However, soil profiles indicated that
steady-state evaporative discharge was occurring in a number of areas. These areas
correspond to the Vapour Transport Zone (VTZ) of the conceptual model and typically had
measured evaporative discharge rates of 0.2-12 mm y-1. The VTZ was assigned a conservative
range of 0.2-5 mm y-1 for use in the estimates of evaporative discharge.
5. A range of satellite data were used to classify discharge zones. ASTER and Landsat were used
for the automated classification/mapping of evaporative discharge zones. Automated
supervised classification using a selection of band ratios and indices were selected to map
the discharge zones identified by the conceptual model. Indices mapping soil moisture were
used to delineate the LTZ. Indices mapping albedo and salt absorption features in the
absence of high soil moisture were used to map the MTZ.Due to a lack of surface
characteristics, the VTZ was defined using surface elevation data and interpolated water
table surfaces. We imposed an arbitrary radius of 10 km around high discharge zones (LTZ,
MTZ) and classified areas within this boundary having depths to the water table of <10 m as
forming the VTZ.
6. A landform mapping approach was also used to map the field area into the conceptual
discharge zones using a combination of data sources, including satellite and airborne remote
sensing, field mapping, field measurements of evaporative discharge and digital elevation
data. The landform mapping approach is considered to provide a maximum estimate of the
high discharge zones due to its more interpretative nature that lumped areas together. In
comparison to the landform mapping approach, the automated classification procedure of
the satellite data underestimated the area of high discharge zones due to pixel mixing
effects.
7. The minimum and maximum estimated evaporative discharge rates, for each of the
evaporative discharge zones, were applied to the mapped area of these zones to estimate
the range of steady-state evaporative discharge over the southwestern margin of the GAB.
These discharge estimates were then compared to modelled estimates of vertical leakage
from the Bureau of Rural Sciences (BRS) steady-state GABFLOW model.
8. The higher evaporative discharge zones (LTZ, MTZ,) mapped by automated classification of
satellite data account for 8-28% of the total vertical leakage component modelled by BRS.
Areas of evaporative discharge in the western sub-basin account for 7-24% of the modelled
vertical leakage, areas from the mixing zone account for 1-3% and areas from the eastern
sub-basin account for <1%. These are considered to represent minimum estimates due to
underestimation of high discharge areas.
9. The higher evaporative discharge zones (LTZ, MTZ) estimated by landform mapping account
for 73-251% of the total vertical leakage component modelled by BRS. Areas of evaporative
discharge in the western sub-basin account for 64-216% of the modelled vertical leakage,
areas from the mixing zone account for 5-22% and areas from the eastern sub-basin account
for 4-13%. These are considered to represent maximum estimates because of
overestimation of high discharge areas.
10. The VTZ estimated around areas of landform mapping accounts for 4-100% of the total
vertical leakage component modelled by BRS. Areas of VTZ in the western sub-basin account
for 2-48% of the modelled vertical leakage, areas from the mixing zone account for 1-33%
and areas from the eastern sub-basin account for 1-18%.
11. The mapped distribution of the high discharge areas has important implications for
modelling of the GAB. In the western sub-basin, most of the estimated recharge can be
accounted for by evaporative discharge in the high discharge zones located around the Basin
margins and along fault structures trending south-east of the Peake-Denison Ranges. This
implies that vertical leakage rates distal to the margins are very low, and/or the inflow to
this part of the GAB (either western margin recharge or inflow from deeper basins) is
currently underestimated.
12. The eastern sub-basin in South Australia is characterized by relatively few areas of high
discharge. This indicates that more of the vertical leakage component in the eastern subbasin is occurring distal to the Basin margins. In contrast to the western sub-basin, the
eastern sub-basin generally has much greater depths to the J-K aquifers and also the
presence of non-artesian confined aquifers overlying the J-K aquifers over much of its area
away from the margins. As a result, the pathways for vertical leakage are likely to be more
complex than for the western sub-basin.
Convenor of the GABCC Research and Development Subcommittee - James Hill
Photo: Gayle Partridge
Further information on the Great Artesian Basin
Coordinating Committee and its activities can be found
on the Committee’s website at:
www.gabcc.gov.au