Lower Turner groundwater allocation limit report Method used to set an allocation limit and licensing rules for the lower Turner alluvial aquifer Looking after all our water needs SCT_Online Print_Final_A4.indd 1 31/05/10 11:08 AM Lower Turner groundwater allocation limit report Method used to set an allocation limit and licensing rules for the lower Turner alluvial aquifer Looking after all our water needs Department of Water Water resource allocation and planning series Report no. 50 June 2011 Department of Water 168 St Georges Terrace Perth Western Australia 6000 Telephone +61 8 6364 7600 Facsimile +61 8 6364 7601 National Relay Service 133 677 www.water.wa.gov.au © Government of Western Australia 2011 June 2011 This work is copyright. You may download, display, print and reproduce this material in unaltered form only (retaining this notice) for your personal, non-commercial use or use within your organisation. Apart from any use as permitted under the Copyright Act 1968, all other rights are reserved. Requests and inquiries concerning reproduction and rights should be addressed to the Department of Water. ISSN 1327-8428 (print) ISSN 1834-2620 (online) ISBN 978-1-921789-66-3 (print) ISBN 978-1-921789-67-0 (online) Acknowledgements The Department of Water would like to thank the following for their contribution to this publication: Mike Braimbridge, Darryl Abbott, Fiona Lynn, Michelle Antao, Robyn Loomes, Emily Said, Hazli Koomberi and Chris O’Boy. The Department of Water would also like to thank the Kariyarra traditional owners and the Pilbara Native Title Service for their assistance with identifying the cultural values of the study area. For more information about this report, contact: Allocation Planning Section Department of Water Telephone 08 6364 7600 Email [email protected] Disclaimer This document has been published by the Department of Water. Any representation, statement, opinion or advice expressed or implied in this publication is made in good faith and on the basis that the Department of Water and its employees are not liable for any damage or loss whatsoever which may occur as a result of action taken or not taken, as the case may be in respect of any representation, statement, opinion or advice referred to herein. Professional advice should be obtained before applying the information contained in this document to particular circumstances. This publication is available from our website <www.water.wa.gov.au> or for those with special needs it can be made available in alternative formats such as audio, large print, or Braille. Lower Turner groundwater allocation limit report Water resource allocation and planning, no. 50 Contents Summary ..................................................................................................................... v 1 Introduction.............................................................................................................. 1 1.1 Scope of this document ......................................................................................................1 1.2 What is an allocation limit? ................................................................................................. 1 1.3 Process used for setting the lower Turner alluvial aquifer allocation limit ......................... 1 1.4 Need for a water licence .....................................................................................................2 2 The lower Turner resource ...................................................................................... 3 2.1 Resource boundary ............................................................................................................3 2.2 Hydrogeology ......................................................................................................................5 3 Assessment ............................................................................................................. 7 3.1 Assessment panel ..............................................................................................................7 3.2 Aquifer properties ...............................................................................................................7 3.3 Groundwater-dependent ecosystems ................................................................................ 7 3.4 Cultural and social values ................................................................................................. 10 3.5 Consumptive use ..............................................................................................................10 4 Allocation limit decision and licensing rules ........................................................... 12 4.1 Assessment of risks ..........................................................................................................12 4.1.1 Initial risk assessment ........................................................................................................... 12 4.2 Licensing rules and resource management ..................................................................... 13 4.3 Allocation limit and water availability ................................................................................ 14 4.3.1 Final risk assessment ........................................................................................................... 14 4.3.2 Using a risk matrix to determine yield ................................................................................... 14 4.3.3 Allocation limit and water availability ..................................................................................... 15 4.4 Monitoring and reporting ...................................................................................................15 4.5 Review of allocation limits ................................................................................................16 Appendix.................................................................................................................... 17 Glossary .................................................................................................................... 18 References and further reading ................................................................................. 22 Appendix River pools in the lower Turner groundwater resource area ...................................................... 17 Figures Figure 1 Resource boundary of the lower Turner alluvial aquifer .............................. 4 Figure 2 Pools along the lower Turner River that are possibly groundwater- dependent ecosystems and their permanency ........................................... 9 Department of Water iii Water resource allocation and planning, no. 50 Lower Turner groundwater allocation limit report Tables Table 1 Characteristics of interest of the lower Turner alluvium .............................. 5 Table 2 Estimated stock and domestic water use, which is exempt from licensing10 Table 3 Determining the risk of abstraction on in situ values and the risk of limiting water available for consumptive use ......................................................... 12 Table 4 Licensing and management rules for the lower Turner alluvial aquifer ..... 14 Table 5 Risk matrix for determining the proportion of yield for allocation............... 15 Table 6 Allocation limit and components for the lower Turner alluvial aquifer ....... 15 Table 7 Details of location and permanency of pools in the lower Turner Alluvial aquifer. ...................................................................................................... 17 ____________________________________________________________________________________________________________ iv Department of Water Lower Turner groundwater allocation limit report Water resource allocation and planning, no. 50 Summary Demand for groundwater in the lower Turner River area is increasing due to extra water requirements for mining and related industry. To support any development in the area and provide guidance to proponents, the Department of Water (DoW) has set an allocation limit and the licensing rules for the lower Turner alluvial aquifer, which are set out in this report. To determine the lower Turner alluvial aquifer allocation limit, the department has used a risk-based approach (DoW 2010). We use this approach in areas where knowledge about the groundwater resource is limited and competing demands for the water do not exist. This allows us to develop allocation limits and licensing rules quickly and consistently. This approach has four steps: 1 Identify and define the groundwater resource. 2 Describe aquifer properties, groundwater-dependent values and consumptive uses and assess the risks. 3 Assess whether any risks can be managed through licensing rules. 4 Set allocation limits and licensing rules. Using the process outlined above, the department has set an allocation limit for the lower Turner alluvial aquifer of 0.42 GL/yr. As at January 2011, water is still available for licensing. As there is only limited information about this water resource, the department welcomes new investigations and data which would improve our understanding of the aquifer. If new information shows that more water is available than the estimate that has been used in this report, and that the effects of increased abstraction are manageable, then we may review the allocation limit. Department of Water v Lower Turner groundwater allocation limit report Water resource allocation and planning, no. 50 1 Introduction The