The evolution of knowledge and management of springs in the Great Artesian Basin
Steven Flook 1
1. Office of Groundwater Impact Assessment, Brisbane, QLD, Australia
The Great Artesian Basin (GAB) is a regional groundwater system recognised internationally for its significance both as a reliable water source and in facilitating development within Australia’s semi-arid to arid interior. Notably, the GAB’s unique hydrogeological features also result in natural discharge areas, including spring wetlands intrinsically linked to cultural values and endemic flora and fauna.
This presentation will provide an overview and context for this session of the
conference. The content will include a brief synopsis of the values of spring wetlands, the evolution of spring knowledge, and the importance of multidisciplinary science to improve understanding of the ecohydrological processes at GAB springs. The
overarching theme will be the challenge of balancing emerging water demands and threats, scientific uncertainty and conservation outcomes.
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Springs of the Great Artesian Basin – an initiative of the Royal Society of Queensland
Angela Arthington 1
1. Australian Rivers Institute, Griffith University, Brisbane, QLD, Australia
This presentation describes the background and impetus for this Special Session on Springs of the Great Artesian Basin sponsored by the Royal Society of
Queensland. The Royal Society has a long and rich involvement in science dating back to 1859, the year Queensland was proclaimed a separate colony. Publication of the Proceedings of the Royal Society of Queensland is the foundational role of the Society and brings to international attention peer-reviewed research as well as commentary from researchers and practitioners on management applications of science.
From time to time, the Society publishes a Special Issue of its Proceedings devoted to a theme of particular interest. In 2018 the Council of the Society agreed to publish a Special Issue of its Proceedings devoted to Springs of the Great Artesian
Basin. Australia’s Great Artesian Basin springs provide a unique focal point for the intersection of many types of knowledge – First Nations’ and colonial perspectives, discovery, science and management, governance and policy. Progress across these themes has been significant since the early descriptions of the Great Artesian Basin and the ecosystems dependent on groundwater resources, yielding many individual publications and technical reports. The Royal Society recognised the need for
consolidated knowledge to support evidence-based management, and for a strategy for the future of these precious ecosystems. A funding drive has yielded generous contributions to cover publication costs, and to sponsor this Special Session of
the Australasian Groundwater Conference – a very welcome opportunity to showcase some of the exciting papers about springs already in production.
The complete Special Issue will include 20 or so papers spanning Indigenous values and uses of springs, the history of springs research, their distribution, hydrogeology, biodiversity, threats, risks, management strategies and conservation issues and a perspective on the future, given present and future developments and threats.
Digital and print copies of the Special Issue of the Proceedings of the Royal Society of Queensland – Springs of the Great Artesian Basin – can be ordered from the Society.
Artesian springs of the Great Artesian Basin – hydrogeology, hydrochemistry and age dating of artesian groundwater and spring deposits
M.A. Habermehl 1
1. Dr M.A. Habermehl, Kaleen, Canberra, ACT, Australia
Artesian springs of the Great Artesian Basin, Australia, are the natural outlets of the artesian groundwater, and are predominantly found near the Basin’s southern,
south-western, western and northern marginal discharge areas. Artesian springs also occur near the eastern recharge areas. Artesian springs played an important role in the discovery of the Basin’s artesian groundwater and the first flowing artesian waterbores were dug and drilled near springs. The largest concentration of springs and their sedimentary deposits, mainly tufa carbonates, forming conical mounds and
33 | P a g e platforms, occur near the south-western margins. The Basin is a multi-layered confined aquifer system, with aquifers in Jurassic and Cretaceous continental sandstones and intervening confining beds of siltstone and mudstone of the constituent Eromanga, Surat and Carpentaria sedimentary basins.
The Basin underlies semi-arid and arid regions across 1.7 million km2, or one-fifth of Australia. Hydrogeological and hydrochemistry studies show that most artesian springs and waterbores derive their water from the main (tapped) Jurassic-Lower Cretaceous Cadna-owie-Hooray Sandstone aquifer and its equivalents. Age dating by isotope hydrology studies of the artesian groundwater in the Basin determined ages of up to 1 to 2 million years. Drilling of the spring carbonate deposits revealed
thicknesses of up to 30 m. Several age dating studies, including thermoluminescence and uranium series dating of the carbonate mound shaped spring deposits southwest of Lake Eyre, show ages up to 740 000 ± 120 000 years. Spring deposits appear to show a range of episodic ages and could indicate a relationship with wet periods in the recharge areas of the Basin.
1. Habermehl, M.A. (in prep/press/2019) Artesian Springs of the Great Artesian Basin – Hydrogeology, hydrochemistry and age dating of artesian groundwater and spring deposits.
Proceedings Royal Society of Queensland - Springs Special Issue 2019 Habermehl, M.A. (in prep/press/2019) The Great Artesian Basin, Australia – from discovery to current
hydrogeological, hydrochemical and isotope hydrology interpretations. Hydrogeology Journal (2019)
In search of lost springs in the eastern Great Artesian Basin
Jen Silcock 1
1. The University of Queensland, St Lucia, QLD, Australia
Desert springs have captured the human imagination since time immemorial. They have underpinned survival, travel and culture across arid regions globally, as well as supporting unique biological communities, often including species that live nowhere else. However, since the industrial era many have become lost – either through extinction due to groundwater extraction and other human impacts, or simply by virtue of being bypassed with mechanised transport and the proliferation of alternative artificial water sources. Sometimes springs have become extinct both physically and in human geographical knowledge.
It is essential to understand the location, activity status, history and ecological values of springs at a landscape or aquifer scale, in order to effectively manage their values and protect them from current and emerging threats. Over the past three decades, researchers at the Queensland Herbarium and University of Queensland have compiled a comprehensive database of all known active and inactive springs in the eastern Great Artesian Basin (GAB) underlying Queensland and New South Wales, spanning 1.5 million square kilometres. We employed comprehensive field surveys, local knowledge, historical maps, and a review of historical and
contemporary literature. The database includes information on location, activity status, hydrogeology, and cultural and ecological values of nearly 2882 known springs, including 2132 that remain active.
Springs are clustered in nine main groups, termed ‘supergroups’. Cultural and
ecological values vary markedly between and within groups, as do activity status and threats. This presentation will provide a summary of the approaches to building spring knowledge across the Great Artesian Basin and the role of the spring database
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support.
Macro-invertebrates of GAB springs: how understanding their distributions can help us conserve them
Renee Rossini 1
1. The University of Queensland, St Lucia, QLD, Australia
Springs are unique freshwater ecosystems that are often overlooked in discussions of global freshwater ecology and conservation. Springs that emerge from the Great Artesian Basin (GAB) in Australia support a high diversity of endemic aquatic species.
Most of these species have a high risk of extinction due to their small geographic distributions and severe habitat loss. However, many are poorly understood and unprotected. They are mostly invertebrates for which basic taxonomic and ecological information is lacking and global impetus for conservation is weak.
Quantifying the hydro-ecological processes that shape and sustain the unique biotic assemblages of discharge spring wetlands of the GAB and predicting how endemic springs taxa will respond to threatening processes, will help us prioritise our conservation actions for this huge suite of species. In this talk I will give a crash course in the biodiversity of invertebrates in GAB springs, discuss our current understanding of threats to their persistence, and briefly propose a functional approach to predicting their risks of extinction.
Evolution in isolation: the endemic fishes of Australia’s remote Great Artesian Basin springs
Adam Kerezsy 1
1. Dr Fish Contracting, Lake Cargelligo, NSW, Australia
Patterns of fish distribution within Great Artesian Basin springs fall into two distinct categories: the opportunistic colonisation of springs by widespread riverine species following flooding, and long-term habitation – and speciation – within isolated spring complexes by fishes’ endemic to certain spring groups.
The endemic fishes of Australia’s Great Artesian Basin springs persist in the most unlikely fish habitats imaginable. Within predominantly hot and dry landscapes, they inhabit the only reliable wet areas, which are frequently the same temperature as the surrounding plains and as shallow as the body depth of some of the species.
There are seven fish species endemic to Great Artesian Basin springs; the Dalhousie catfish (Neosiluris gloveri), Dalhousie hardyhead (Craterocephalus dalhousiensis), red-finned blue-eye (Scaturiginichthys vermeilipinnis), three localised species of gobies (Chlamydogobius gloveri, C. micropterus and C. squamigenus) and the Dalhousie mogurnda (Mogurnda thermophila). These species occur at only three locations; Dalhousie in South Australia, and Edgbaston and Elizabeth Springs, which are both in Queensland.
All spring species are functionally endangered due to their small ranges and small populations; however their formal status varies widely between state, national and international legislation and/or lists. All fish endemic to GAB springs are threatened by a broad suite of factors that endanger inland aquatic ecosystems, such as water
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Persisting as they do in such unique and specialised habitats, the study of these GAB fish – and all GAB springs endemics - can reveal much about evolution, speciation and resilience. It is therefore imperative that we respect and preserve them and their unusual habitats. Although there is a growing recognition that conservation of the fishes and their habitats is important, this is complicated by the confusing variability of their conservation status and a lack of basic knowledge regarding their ecology and precise distribution. This presentation will provide an overview of the unique fish species that rely on GAB springs and the challenge in conserving species where there is only limited knowledge.
Regulatory tools for managing resource development impacts on spring ecosystems
Revel Pointon 1
1. EDO Queensland, West End, QLD, Australia
Springs of the Great Artesian Basin (GAB) and other similar regional aquifer systems provide essential water flow to support unique ecological communities, ecological processes and cultural values. There are a number of regulatory tools designed to facilitate the protection of these values.
This presentation will provide an overview of the legal framework that seeks to regulate impacts on groundwater and springs in Australia, particularly from a federal level under the Environment Protection and Biodiversity Conservation Act
1999 (EPBC Act). They will include a brief overview of the Australian regulatory framework, the known ecological values of spring ecosystems - listed and those that are not – and analysis of how the framework is operating in practice, with case study examples, and consideration of potential for improvements.
Twenty years on from the EPBC Act commencement, this presentation provides a reflection on the effectiveness and adequacy of the regulatory framework to manage impacts on these unique ecosystems. The two key challenges of focus will be the existing regulatory process, particularly focusing on its application where there is scientific uncertainty, and the framework for listing species and communities.
Recent examples of resource activities proposed in the vicinity of spring systems in Queensland, Australia, will be reviewed to better understand how the regulatory framework is operating in practice and to consider whether improvements may be implemented to more effectively manage the competing agendas of resource development and springs protection.
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An adaptive management plan for GAB springs
Lynn Brake 1
1. University of South Australia, Brighton, SA, Australia
The Great Artesian Basin (GAB) is one of Australia’s most important natural assets.
It is among the largest artesian aquifer system in the world, and Australia’s largest freshwater resource. GAB springs, the natural surface expressions of the GAB aquifers, have iconic geological, cultural and ecological values that are widely recognised both nationally and internationally. They are one of the few major artesian spring systems in the world that have not been severely degraded by over- exploitation of the water-bearing aquifers and/or the impacts of land-use in and around spring vents
An adaptive Management Plan has been developed to protect active GAB Springs on land used for pastoral production, mining or other purposes. The Plan is designed to protect asset values of springs with as little disruption to productive land uses as practicable. It is built around an evidence-based template that facilitates cooperative spring management between landholders and management agencies. The template consists of practical, cost effective methodologies to:
• Classify springs and identify important values and threats to particular spring groups
• Identify risks that may arise from various types of land uses
• Develop intervention strategies to manage the risks with as little disruption to land uses as practicable
• Monitor changes that indicate how well risks are being managed
• Modify on-ground management in response to changing conditions
The Template called Springs on Your Place is designed to be easily understood by landholders and water managers as well as other government and industry decision makers. It is built around an attractive, easy to use graphic database that provides robust information on each of the spring groups within the 13 super groups across the GAB. Springs on Your Place uses best and most up-to-date local and scientific knowledge and has the capacity to be revised and updated as knowledge gaps are filled, decisions made, and spring conditions change. Springs on Your Place can be a key consultation tool between landholders and department staff to aid in decision making about the most appropriate management response for particular spring groups.
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