Goulburn River reach report Constraints Management Strategy July 2015 Goulburn reach report, Constraints Management Strategy Published by the Murray‒Darling Basin Authority Postal Address: GPO Box 1801, Canberra ACT 2601 Telephone: (02) 6279 0100 international + 61 2 6279 0100 Facsimile: (02) 6248 8053 international + 61 2 6248 8053 Email: [email protected] Internet: http://www.mdba.gov.au ISBN (online): 978-1-925221-03-9 All material and work produced by the Murray‒Darling Basin Authority constitutes Commonwealth copyright. MDBA reserves the right to set out the terms and conditions for the use of such material. With the exception of the Commonwealth Coat of Arms, photographs, the Murray‒Darling Basin Authority logo or other logos and emblems, any material protected by a trade mark, any content provided by third parties, and where otherwise noted, all material presented in this publication is provided under a Creative Commons Attribution 3.0 Australia licence. http://creativecommons.org/licenses/by/3.0/au © Murray‒Darling Basin Authority 2015. The Murray‒Darling Basin Authority’s preference is that you attribute this publication (and any Murray‒ Darling Basin Authority material sourced from it) using the following wording within your work: Title: Goulburn River reach report: Constraints Management Strategy. Source: Licensed from the Murray‒Darling Basin Authority under a Creative Commons Attribution 3.0 Australia Licence. As far as practicable, material for which the copyright is owned by a third party will be clearly labelled. The Murray‒Darling Basin Authority has made all reasonable efforts to ensure that this material has been reproduced in this publication with the full consent of the copyright owners. Inquiries regarding the licence and any use of this publication are welcome by contacting the Murray‒ Darling Basin Authority. Cover image: Floodplain vegetation in the lower Goulburn near Stewarts Bridge Road, 2013. Photo: Janet Pritchard, MDBA. Edited by Biotext, Canberra. Disclaimer To the extent permitted by law, the Murray‒Darling Basin Authority and the Commonwealth excludes all liability to any person for any consequences, including but not limited to all losses, damages, costs, expenses and any other compensation, arising directly or indirectly from using this report (in part or in whole) and any information or material contained within it. Accessibility Australian Government departments and agencies are required by the Disability Discrimination Act 1992 (Cwth) to ensure that information and services can be accessed by people with disabilities. If you encounter accessibility difficulties or the information you require is in a format that you cannot access, please contact us. Acknowledgement of the Traditional Owners of the Goulburn waterways MDBA acknowledges and pays its respects to the Taungurung and Yorta Yorta people as the Traditional Owners of the land surrounding and the catchment of the Goulburn River downstream of Eildon Dam. MDBA recognises and acknowledges that the Traditional Owners and their Nations have a deep cultural, social, environmental, spiritual and economic connection to their lands and waters. Page ii Goulburn reach report, Constraints Management Strategy Contents Summary..................................................................................................................................... 1 What is the Constraints Management Strategy? ..................................................................... 8 Why is the Strategy important? .............................................................................................. 17 What is happening in the Goulburn River? ............................................................................ 23 What flows are being considered for the Goulburn River? ................................................... 32 What might be the effect of the proposed flows in the Goulburn River? ............................. 41 What does the community think? ........................................................................................... 45 What happens next? ................................................................................................................ 52 What is happening in the subreaches? .................................................................................. 58 Eildon Dam to Killingworth ................................................................................................ 63 Killingworth to Mitchellstown ............................................................................................. 92 Mitchellstown to Kialla ..................................................................................................... 106 Kialla to Loch Garry ......................................................................................................... 116 Loch Garry to the River Murray ....................................................................................... 127 Appendix 1 Constraints of the Goulburn River ............................................................... 136 Appendix 2 Environmental water management in Victoria ............................................ 144 Appendix 3 Constraints-related studies relevant for the Goulburn River ..................... 151 Appendix 4 Changes to the Shepparton ratings table .................................................... 155 Appendix 5 Examples of flow events along the Goulburn River ................................... 157 Appendix 6 Easements ..................................................................................................... 160 Appendix 7 Flow interactions between tributaries and the main stem ......................... 164 References ........................................................................................................................ 167 Structure of this report This Goulburn reach report has two main parts. The first part describes what is happening in the Goulburn River, what the Constraints Management Strategy is designed to achieve and what effects it could have. It includes: What is the Constraints Management Strategy? Why is the Strategy important? What is happening in the Goulburn River? What flow footprints are being considered for the Goulburn River? What might be the effect of the proposed flow footprints in the Goulburn River? What does the community think? In the second part, 'What is happening in the subreaches?', each chapter focuses on one subreach and has been designed as stand-alone documents to allow people to easily find information on the area of the Goulburn River they are particularly interested in. Page iii Goulburn reach report, Constraints Management Strategy Summary For the past century, the Murray–Darling Basin (the Basin) has been developed with a focus on delivering water for productive use. Large dams have been built to capture and store as much water as possible to be used later for consumption and irrigation. There have also been many rules put in place across the Basin around how the rivers and dams are managed. These structures and practices are of great benefit to our industries and have greatly supported the building of our nation, our Basin communities and our economy. However, the changes we have made have affected how, when and where the Basin's rivers flow and how healthy they are. Water that once flowed downstream is now often stored, and delivered in regular patterns at times that suits production, not necessarily in a more natural variable way that most benefits and supports the environment. For many floodplain areas of the Basin, the time between drinks is now too long for floodplain plants and animals. Overbank flows that connect the river to its floodplain are vital to the environment. These overbank flows improve water and soil quality, recharge groundwater, and support native plant and animal species. Before rivers were regulated, these flows were far more common. The lack of these flows is affecting long-term river and floodplain health, and ultimately Basin communities and businesses who rely on healthy waterways. Environmental watering has been successfully done for many years in some parts of the Basin, and is one way we can deliver water to benefit the environment. However, there would be many environmental benefits if we could deliver slightly higher flows in the future to reach the floodplains (up to flows in the minor flood level range). So, state and federal governments requested that the Basin Plan include a Constraints Management Strategy (the Strategy) to explore how this might be done. The Constraints Management Strategy The Strategy is about ensuring that water can flow onto the floodplain, while mitigating any effects this water may have on property and people. For the purpose of the Strategy, constraints are river rules, practices and structures that restrict or limit the volume and/or timing of regulated water delivery through the river system. The Strategy seeks to find smarter ways to operate our highly regulated rivers to increase how often overbank flows below and in the minor flood range occur to sustain and improve floodplain health. Given consumption and irrigation needs, it is not possible, nor is it the goal, to return regulated rivers to their ‘natural’ or ‘without-development’ flows. The Strategy is also not trying to create or change how often damaging moderate and major floods occur. The idea is to make modest regulated releases from storages, generally when higher flows downstream would have