BARMAH FOREST SEASONAL WATERING PROPOSAL 2017- 2018 (VEWH ADDENDUM) Seasonal Watering Proposal 2017-2018
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BARMAH FOREST SEASONAL WATERING PROPOSAL 2017- 2018 (VEWH ADDENDUM) Seasonal Watering Proposal 2017-2018 Keith Ward & Lisa Duncan [email protected] Barmah Forest Seasonal Watering Proposal 2017-2018 (VEWH Addendum) Publication details Published by: Goulburn Broken Catchment Management Authority, PO Box 1752, Shepparton 3632 © Goulburn Broken Catchment Management Authority, 2017. Please cite this document as: GB CMA (2017). Barmah Forest Seasonal Watering Proposal 2017-2018 (VEWH Addendum). Goulburn Broken Catchment Management Authority, Shepparton. Disclaimer: This publication may be of assistance to you, but the Goulburn Broken Catchment Management Authority does not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequences which may arise from you relying on information in this publication. It should be noted that specific reference to funding levels in this strategy are for indicative purposes only. The level of Government investment in this plan is contingent on budgets and government priorities. For further information, please contact: Goulburn Broken Catchment Management Authority P.O. Box 1752, Shepparton 3632 Phone: (03) 5822 7700 Website: www.gbcma.vic.gov.au 1 Barmah Forest Seasonal Watering Proposal 2017-2018 (VEWH Addendum) EXECUTIVE SUMMARY Managers of Barmah-Millewa Forest have been invited by the environmental water holders to submit a single seasonal watering proposal this year instead of submitting two separate proposals for the Victorian and NSW sides of the forest. This is in recognition of the forest reserve being a single floodplain ecosystem which is best managed as a whole. Managers in Victoria and NSW work together to achieve the best possible environmental outcomes for both sides of the forest. This document provides the additional information required by the Victorian Environmental Water Holder (VEWH) for all Victorian seasonal watering proposals. This document, in addition to the 2017- 18 SCBEWC Environmental Water Proposal Template jointly prepared for Barmah-Millewa Forest, forms the 2017-18 Seasonal Watering Proposal for Barmah-Millewa Forest and outlines the combined Goulburn Broken Catchment Management Authority (GB CMA) and NSW Office of Environment and Heritage (OEH) priorities for the use of environmental water in the Barmah- Millewa Forest in 2017-18. Barmah-Millewa Forest experienced significant unregulated flooding in 2016-17, inundating most of the floodplain in both Barmah and Millewa Forests for over a month and the lower regions of the floodplain for over six months. Environmental water delivery occurred to extend the duration and maintain depth on Floodplain Marsh wetlands which was concentrated mainly in Barmah Forest within the current flow constraints in the Murray River downstream of Yarrawonga (15,000 ML/d). Millewa Forest also received some of this environmental water during the period of environmental water delivery. Both forests also received additional environmental water to support waterbird breeding activity that occurred in both forests. The overarching objective for water management at Barmah-Millewa Forest in 2017-18 is to minimise hypoxic blackwater development and to promote spring flooding with an autumn dry period on the floodplain marsh plains of Barmah-Millewa Forest, as well as achieving native fish and waterbird breeding outcomes. Additionally, as it is Millewa Forest’s turn to take unseasonal flooding events as part of the annually-alternating reciprocal arrangement, water management will attempt to minimize unseasonal flooding on Floodplain Marsh plains by instead diverting unseasonal flooding to Giant Rush dominated wetlands. To achieve this, the broad aims of 2017-18 watering proposal for Barmah-Millewa Forest are to: Minimise hypoxic blackwater development through early season flushing. Maintain drought refuge for floodplain-specialist fish species and turtles. Enhance vegetation health of wetlands, watercourses and forest communities on the lower terraces of the floodplain, with particular emphasis on re-invigorating Floodplain Marsh species such as Moira Grass and potentially expanding its distribution on the floodplain. Promote the recovery of native fish populations in and around Barmah-Millewa Forest. Facilitate waterbird breeding success. Provide breeding and feeding habitat opportunities for floodplain fauna, such as waterbirds, fish, frogs and turtles. Minimise summer-autumn unseasonal flooding on Floodplain Marsh plains. A range of priority water management actions have been identified by this proposal under various water resource scenarios to achieve these aims, being: 2 Barmah Forest Seasonal Watering Proposal 2017-2018 (VEWH Addendum) A. Perch spawning pulses: Provide flow variability within the main river channel in mid-October through to December to encourage the spawning of native fish species, primarily Golden Perch and Silver Perch. B. Critical drought refuge: Maintain critical drought refuge areas within Barmah-Millewa waterways, without return flow connectivity to the river system C. General drought refuge: Maintain general drought refuge areas within Barmah-Millewa waterways, with return flow connectivity to the river system D. Waterbird breeding (Dry scenario): Initiate and sustain a targeted waterbird (colonial- nesting species and bitterns) breeding event in either Reed Beds swamp or Boals Deadwoods by providing cues and suitable conditions for successful breeding. E. Waterbird breeding (Moderate & Near Average scenarios): Initiate and sustain a targeted waterbird (colonial-nesting species and bitterns) breeding event in both Reed Beds swamp or Boals Deadwoods by providing cues and suitable conditions for successful breeding. F. Waterbird breeding (Wet scenario): Same as Action E but includes additional wetlands. G. Floodplain Marsh: Build on natural flow cues to enhance conditions to promote growth of Floodplain Marsh vegetation species (including Moira Grass) on treeless plains in Millewa Forest (given Millewa Forest turn under annual-alternating flood strategy with Barmah Forest). H. Summer-autumn perennial flow trial 2017-2019: Trial to determine if large bodied native fish occupy the perennially flowing habitats but exit (or attempt to exit) the seasonal habitat when flows cease. I. Autumn-winter perennial flow trial 2017-2019: Trial to determine if large bodied native fish occupy the perennially flowing habitats but exit (or attempt to exit) the seasonal habitat when flows cease. J. Translucency flows: Trial translucent regulator strategy where forest regulators will be open in winter-spring and then closed at the end of November. The strategies are partially tiered under water resource scenarios such that higher-level floodplain inundation events can negate the need for lower floodplain watering actions. Engagement of program partners, recreational users, environment groups, landowners, traditional owners and councils on the seasonal watering proposal planning process for 2017-18 has occurred (mainly via the BM Technical Advisory Group, BM Operations Advisory Group, and the CMA’s Wetland Advisory Group) with input and feedback sought from multiple advisory groups and through direct communication. No major delivery or external flooding risks are foreseen with the proposed watering strategy. Flow constraints in the Murray River below Yarrawonga are in place to prevent flooding of private land access on the Bullatale Creek system in NSW. More detailed consideration of available environmental water volumes and natural triggers will be made prior to water release to ensure greatest chance of achieving target environmental outcomes. Control of feral horses from Barmah Forest from priority Floodplain Marsh wetlands is planned to be initiated by Parks Victoria throughout 2017-18. However, reaching the goals outlined in this strategy will be largely dependent upon the provision of requested flow volumes from the environmental water holders. A summary of the planned 2016-17 environmental watering actions for Barmah Forest under the different water resource scenarios identified by this Seasonal Watering Proposal is provided in Section 6 Scenario planning and prioritisation. 3 Barmah Forest Seasonal Watering Proposal 2017-2018 (VEWH Addendum) CONTENTS Executive summary ................................................................................................................................. 2 Introduction ............................................................................................................................................ 5 Engagement ............................................................................................................................................ 6 Engagement ......................................................................................................................................... 6 Shared Benefits ................................................................................................................................... 8 Environmental Objectives and Flow Recommendations ........................................................................ 9 Seasonal Review...................................................................................................................................... 9 2016-2017 Ecological Review .............................................................................................................