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Lake Eyre Basin Springs Assessment Project Hydrogeology, cultural history and biological values of springs in the Barcaldine, Springvale and Flinders River supergroups, Galilee Basin and Tertiary springs of western Queensland 2016 Department of Science, Information Technology and Innovation Prepared by R.J. Fensham, J.L. Silcock, B. Laffineur, H.J. MacDermott Queensland Herbarium Science Delivery Division Department of Science, Information Technology and Innovation PO Box 5078 Brisbane QLD 4001 © The Commonwealth of Australia 2016 The Queensland Government supports and encourages the dissemination and exchange of its information. The copyright in this publication is licensed under a Creative Commons Attribution 3.0 Australia (CC BY) licence Under this licence you are free, without having to seek permission from DSITI or the Commonwealth, to use this publication in accordance with the licence terms. You must keep intact the copyright notice and attribute the source of the publication. For more information on this licence visit http://creativecommons.org/licenses/by/3.0/au/deed.en Disclaimer This document has been prepared with all due diligence and care, based on the best available information at the time of publication. The department holds no responsibility for any errors or omissions within this document. Any decisions made by other parties based on this document are solely the responsibility of those parties. Information contained in this document is from a number of sources and, as such, does not necessarily represent government or departmental policy. If you need to access this document in a language other than English, please call the Translating and Interpreting Service (TIS National) on 131 450 and ask them to telephone Library Services on +61 7 3170 5725 Citation Fensham, R.J., Silcock, J.L., Laffineur, B., MacDermott, H.J. 2016, Lake Eyre Basin Springs Assessment Project: Hydrogeology, cultural history and biological values of springs in the Barcaldine, Springvale and Flinders River supergroups, Galilee Basin springs and Tertiary springs of western Queensland. Report to Office of Water Science, Department of Science, Information Technology and Innovation, Brisbane. Front Cover: Edgbaston Springs and a spring (imaginatively) called “New Big”. There is Spinifex in the foreground, free water in the mid-ground, with some scalding in front and the far right rear. Photo: Queensland Herbarium. May 2016 Lake Eyre Basin Springs Assessment Report Executive Summary The Lake Eyre Basin Springs Assessment provides information on the history, ecology, hydrogeology and potential impacts of mines and proposed mining developments on spring ecosystems in the Barcaldine, Flinders River, Springvale supergroups (Eromanga and Carpentaria Basins), the Galilee Basin and springs in Tertiary sandstone in the current drainage area of the Lake Eyre Basin. A database has been developed that includes attributes relating to their physical characteristics, biological values and water chemistry. The database links to a photo library, and historical and hydrogeology reports. Springs can be distinguished as either outcrop (emanating under gravity through outcropping rocks) or discharge (flowing through an aquitard under artesian pressure) types. Discharge springs within the GAB are protected under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). The discharge springs of the Barcaldine and Springvale supergroups which remain active have exceptionally high biological values including concentrations of endemic fish, snails, crustacea and plants that only occur in these habitats. There are also endemic plants that occur in the salt scalds around the spring wetlands. Pelican Creek near Aramac and Elizabeth Springs near Boulia are outstanding in terms of their biological significance and include multiple species that are restricted to those locations. Our understanding of the cultural significance of the springs for Aboriginal people is extremely deficient. However, the patchy evidence we have compiled, stories from elsewhere, and the surface archaeological record reveal their significance both as water supplies and sacred sites. The springs were critical to the European settlement of the Lake Eyre Basin, and they were a focus of attention for the early land surveyors. Homesteads and hotels were built on springs and roads traced the ground between them. The springs were also signposts to the vast aquifer that would later be named the Great Artesian Basin (GAB). From the 1880s thousands of artesian bores were drilled to exploit the groundwater of the GAB. The bores transformed the productive potential of inland Australia, but most of the water flowed down open drains and was lost to evaporation. Declining aquifer pressure resulted in springs ceasing to flow. The current audit of spring complexes (clusters of springs in the same area within a single geomorphic setting) indicates that 31% of the discharge spring complexes in the Barcaldine supergroup; 77% of the Flinders River supergroup; and 50% of the Springvale supergroup have lost more than 80% of their springs. Outcrop springs in the Tertiary sandstone can become inactive without aquifer drawdown and some may require local excavation to maintain their flows. The Great Artesian Basin Sustainability Initiative has provided large-scale investment into rehabilitating bores to stem the profligate waste of groundwater and restore aquifer pressure. This has not resulted in the reactivation of springs, but may serve to minimise further loss. Large free- flowing bores await capping in Queensland particularly in the area of the Flinders River supergroup. Preservation and conservation effort should be directed to the spring wetlands which still support endemic species. The recovery efforts for the Critically Endangered red-finned blue-eye i Department of Science, Information Technology and Innovation (Scaturiginichthys vermeilipinnis) at the Pelican Creek Springs require ongoing support for an achievable outcome. Coal beds within the Permian sediments of the Galilee Basin are the target of future development proposals. Springs discharge from aquifers within these sediments, and the largest and most significant is the Mellaluka Springs. Based on endemicity these springs are not of high conservation value and will probably become inactive if the cumulative impact of the development proposals is realised. A complex of springs at Doongmabulla with very high conservation values, including many endemic plants, has ambiguous hydrogeology. The springs may have a groundwater source in Triassic sediments that are separated from the Permian coal-beds by an aquitard. There is also some potential for their source to be from Permian sediments. Further investigations of the potentiometric surface in the Triassic and Permian aquifers, fault structures and source aquifer chemistry may resolve the origin of the Doongmabulla Springs and contribute to determining the impact of the proposed Carmichael Mine development. The methods developed here for collating the values of spring ecosystems and their aquifer sources should be extended to other regions so that future developments that impact on groundwater can be adequately informed. Acknowledgments We are grateful to the many landholders and managers who have allowed us access to their properties, provided hospitality and directions, and enriched our experience of the springs through their stories and interest. We also thank former landholders and long-term residents for sharing their knowledge of springs. Russell Fairfax initiated and assembled a previous version the springs database and answered many questions about the sources of obscure springs and provided suggestions as to their potential significance, tangible and intangible, during the course of this project. Adam Kerezsy is thanked for his input in relation to fish, Renee Rossini for summarising information about snails. Winston Ponder has also made a major contribution in relation to invertebrates of the springs. Don Butler and Keryn Oude-egberink assisted with the administration of the project. Many people provided able field assistance over the years on the long and winding springs trail, especially Jeremy Drimer, Katharine Glanville, Chris Pennay, Al Healy, Peter McRae, Tracy Wattz, Adam Kerezsy, Cameron Kilgour, Owen Powell and Maree Winter. Ashley Bleakley, John Webb, Tim Ransley and Daniel Larsen have provided valuable input into developing an understanding of the hydrogeology of the springs. Ashley in particular has been indispensable. Rien Habermehl, Bruce Radke, Steve Flook and Jim Kellett have also contributed to the hydrogeology presented here. Steve and Leon Leach provided helpful review of the Doongmabulla chapter. Funding for this work was provided from the Australian Government’s Bioregional Assessment Programme www.bioregionalassessments.gov.au ii Lake Eyre Basin Springs Assessment Report Contents 1 Introduction ........................................................................................................................... 18 1.1 LEBSA and report overview 18 1.1.1 Geographical scope of LEBSA and hydrological overview 20 1.1.2 Report outline 22 1.2 Springs in LEBSA region 22 1.2.1 Great Artesian Basin springs 22 1.2.2 Galilee group 23 1.2.3 Tertiary springs 23 1.3 Cultural history overview 24 1.3.1 Aboriginal history 24 1.3.2 European history 24 1.4 Biological values 27 1.5 General threats and management actions 28 1.5.1 Groundwater use and preservation