Environmental Water Management Plan for the Murray River from Lock 6 – Lock 10 Environmental Water Management Plan for the Murray River from Lock 6 to Lock 10 Environmental Water Management Plan for the Murray River from Lock 6 – Lock 10 DOCUMENT CONTROL Revision and Distribution Version no. Description Issued to Issue date Environmental Water Management 1 Plan for the Murray River from Lock 6 Jane White 9 January 2015 to Lock 10 - System Characterisation 2 Review Simone Wilkie, Riverness 27 April 2015 3 Final Draft Jane White 30 April 2015 Citation Ecological Associates (2015). Environmental Water Management Plan for the Murray River from Lock 6 to Lock 10 - System Characterisation. Ecological Associates report AL043-1-A prepared for Mallee Catchment Management Authority, Irymple. Contact For queries regarding this document, please contact: Louise Chapman [email protected] Waterways Coordinator Mallee Catchment Management Authority This publication may be of assistance to you but the Mallee Catchment Management Authority and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purpose and therefore disclaims all liability for any error, loss or other consequence that may arise from you relying on any information in this publication. Environmental Water Management Plan for the Murray River from Lock 6 – Lock 10 Contents Executive Summary ...................................................................................................................................i 1 Acknowledgements .......................................................................................................................... 1 2 Introduction ....................................................................................................................................... 2 4 Site Overview ................................................................................................................................... 4 4.1 Site Location ............................................................................................................................. 4 4.2 Catchment Setting..................................................................................................................... 4 4.3 Land Status and Management .................................................................................................. 5 4.4 Wetland Characteristics - Floodplain Morphology and Hydraulics ........................................... 6 4.5 Management Scale ................................................................................................................. 25 4.6 Environmental Water Sources (Victorian Sites) ...................................................................... 25 6 Hydrology and System Operations ................................................................................................ 28 6.1 Hydrology of the Murray River ................................................................................................ 28 6.2 Hydrogeology .......................................................................................................................... 29 6.3 Hydraulic Effects of the Weirs ................................................................................................. 33 6.4 Environmental Watering .......................................................................................................... 38 8 Water Dependent Values ............................................................................................................... 44 8.1 Listed Flora ............................................................................................................................. 44 8.3 Fauna ...................................................................................................................................... 47 10 Ecological Objectives and Hydrological Requirements .............................................................. 53 10.1 Management Goal ............................................................................................................... 53 10.2 Ecological Objectives .......................................................................................................... 53 10.3 Watercourses ...................................................................................................................... 53 10.4 Semi-permanent Wetlands .................................................................................................. 56 10.5 Temporary Wetlands ........................................................................................................... 58 10.6 River Red Gum Forest and Woodland ................................................................................ 59 10.7 Lignum Shrubland and Woodland ....................................................................................... 61 10.8 Black Box Woodland ........................................................................................................... 63 11 Hydrological Objectives .............................................................................................................. 65 11.1 Summary of hydrological objectives .................................................................................... 65 11.2 Environmental Water Management Measures .................................................................... 66 11.3 Fish Passage ....................................................................................................................... 66 11.4 Weir Pool Variation .............................................................................................................. 68 11.5 Regulation of Wetlands ....................................................................................................... 68 Environmental Water Management Plan for the Murray River from Lock 6 – Lock 10 11.6 Flowing Habitat .................................................................................................................... 69 12 Environmental Water Delivery Infrastructure .............................................................................. 73 12.1 River System Management - Storages ............................................................................... 73 12.2 River system management - South Australian entitlement flow .......................................... 77 12.3 Flowing Habitat .................................................................................................................... 79 12.4 Floodplain Inundation Projects ............................................................................................ 80 14 Managing Risks to Achieving Objectives.................................................................................... 84 14.1 River System - Environmental Water Delivery Constraints ................................................. 84 14.2 Locks and Weirs .................................................................................................................. 85 14.3 Considerations in Weir Manipulation ................................................................................... 97 16 Knowledge Gaps and Recommendations ................................................................................ 104 16.1 Ecological Objectives and Risks ....................................................................................... 104 16.2 Integrated Regional Objectives ......................................................................................... 105 16.3 River Hydraulics and Operations ....................................................................................... 106 Bibliography ......................................................................................................................................... 108 Appendix 1. Weir Stability.................................................................................................................... 113 Environmental Water Management Plan for the Murray River from Lock 6 – Lock 10 Executive Summary Environmental Water Management Plans (EWMPs) have been developed for key sites in the Mallee region. The Mallee Waterway Strategy 2014-22 (Mallee CMA, 2014) identified 23 Waterway Management Units (WMU) from 216 targeted waterways in the Mallee. The interconnectedness and commonality of threats impacting on the waterways values were used to group them into planning units. This EWMP has been prepared for the river channel, wetlands and floodplain between Lock 6 and the upper limit of the Lock 10 weir pool in the Darling and Murray rivers. This region includes areas in Victoria and New South Wales. Although EWMPs are a Victorian water management instrument, this document has been prepared cooperatively with all jurisdictions to provide a reference and guide to environmental water management for the entire reach. The area able to be inundated through environmental water management will be subject to specific negotiations on the operation of the Locks and the installation of infrastructure as proposed. The study area supports important conservation values that are subject to significant water-related threats. It supports important populations of native fish, birds, reptiles and extensive communities of floodplain vegetation. Many plant and animal species are rare or threatened and several birds are migratory species that are protected under international agreements. These values are threatened