Salinity Provinces In Salinity VictorianProvinces Bio-regions and risk

assessment of environmentalAugust 2011 asset regions in - 2011 Short Title: Salinity Provinces In Victorian Bio-regions

Long Title: Mapping of Salinity Provinces for risk assessment of environmental asset regions in Victoria – 2011

Project CMI Number: 102553 – Statewide Salinity Research and Support

Authors : Mark Reid, Xiang Cheng, Michael Adelana, Peter Hekmeijer, Hanna Zydor, Bruce Gill

Future Farming Systems Research Department of Primary Industries Cnr Midland Hwy & Taylor St, Epsom Victoria 3551 Phone: (03) 5430 4444 Fax: (03) 5430 4304

Department of Primary Industries Future Farming Systems Research Division, Location Address, Victoria,

© The State of Victoria, 2011

ISBN 978-1-74326-194-1 (print) ISBN 978-1-74326-195-8 (online)

Disclaimer This publication may be of assistance to you but the State of Victoria and its employees do 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 consequence which may arise from you relying on any information in this publication.

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Executive Summary

This report introduces the concept of Salinity Provinces as a renewed framework 1 for reporting salinity risk in Victoria and addresses the Department of Sustainability and Environment’s (DSE) requirements for ongoing monitoring and risk assessment for dryland salinity. The identification, prioritisation and mapping of Salinity Provinces form the basis of this report.

High priority salinity provinces have been defined using the following three criteria: • those provinces that intersect with priority areas for biodiversity, especially formally recognised high value environmental assets within these areas; • those provinces that contain salinity hazards or may cause significant damage to high value assets; • those provinces where intervention or mitigation of the threatening salinity hazards is considered feasible and to offer good return for investment in protection or enhancement of the threatened environmental asset.

Based on the intersection of the newly defined salinity provinces with the Victorian “Flagships” and “Biolinks” the most intersected, or highest preliminary priority “Flagship” areas are: • Western Volcanic Plains • South West • Mega Murray • Goldfields

The most intersected “Biolink” area is North and Central Victoria. It covers a large proportion of the State and contains the majority of known salinity. Ideally, these intersected Biolink areas should be given greater importance wherever they intersect with “Flagships” (e.g. Upper Moorabool, Willaura, Pyrenees, Gunbower-Benjeroop, Dimboola).

The most significantly intersected CMA regions in terms of contained high value environmental asset areas threatened by salinity are: • Corangamite • Glenelg-Hopkins • Wimmera • , and • North Central

The identification of new salinity provinces has required significant consolidation and analysis of existing data and knowledge. A comprehensive GIS soil salinity layer provided the spatial distribution for salt- affected soil in Victorian dryland (non irrigated) regions (Clark and Harvey 2008). This spatial layer was

1 The first reference to Salinity Provinces was made in DWR (1986)

Salinity Provinces in Victorian Bioregions – 2011 iii interrogated using knowledge gained from past salinity investigations and an improved understanding of climate impacts to reassess salinity risk and define new salinity hazard areas or ‘salinity provinces’.

Furthermore, our understanding of salinity risk was further enhanced by groundwater flow system (GFS) knowledge, groundwater hydrograph analysis and salt export risk assessments to predict potential risks and consequences for priority assets, particularly those environmental assets found in DSE “Flagship” and “Biolink” areas defined in the Land and Biodiversity White Paper 2010.

Conclusions about the feasibility and likely success of potential salinity interventions are reliant upon GFS knowledge in relation to system behaviour, responsiveness and resilience, the nature and scale of the threat, knowledge of appropriate treatment options and their likely effectiveness at treating either cause or effect.

Key recommendations for future R&D are:

• That higher resolution delineation of key environmental assets needs to be undertaken and collated by DSE and CMA’s in order to focus effort in answering questions of ‘future salinity risk; salinity impact and manageability’ with regard to the impact of salinity within each province on the identified assets. Initial risk/impact assessments to identify additional priority provinces will be required for any key assets that occur outside of 'Flagships' and 'Biolinks' • That the bore monitoring program needs to be adequately resourced, particularly in the high priority provinces so that reliable predictions of salinity risk can be made (once key assets are identified). • That the results of the province identification be used to guide decisions in the monitoring review so as to ensure available resources are directed appropriately. • That key, long-term discharge monitoring sites be maintained in representative priority salinity provinces and that long term monitoring is suitably resourced and targeted to meet the needs of catchment condition reporting and asset risk assessments. • For DPI Landscape and Water Science, and DSE where relevant, the salinity provinces be used as the future framework when undertaking subsequent research and investigation into salinity. • That relevant agencies involved in natural resource management planning and programs around the state be encouraged and assisted to incorporate the new salinity thinking and salinity province work into their NRM planning.

This Technical report is the final milestone for the 2010-2011 Statewide Salinity Research and Support Project funded by the Department of Sustainability and Environment. It directly addresses Objective 1 of the Project Plan by reporting on the current and future salinity risk of environmental asset areas, defined as “Flagships” and “Biolinks” in the Land and Biodiversity White Paper (2010). It contains important information required by DSE to meet reporting requirements for the Natural Resources Management Plan and will inform future investment targeted at managing salinity across Victoria.

Salinity Provinces in Victorian Bioregions – 2011 iv

Contents

1. Introduction ...... 8

Project Outcome ...... 8

Project Background ...... 8

Project Objectives ...... 9 2. Method ...... 10

Project scope ...... 10

Outline of approach ...... 10

Method ...... 10

Products ...... 11 3. Salinity Provinces ...... 12

Introduction ...... 12

Definition of salinity province ...... 12

Background ...... 12 4. Priority areas identified in regional salinity documents ...... 14

Corangamite Region ...... 14

Glenelg-Hopkins Region ...... 16

Wimmera Region ...... 18

Mallee Region ...... 23

North Central Region ...... 27

Goulburn-Broken Region ...... 31

North-East Region ...... 34

East Region ...... 35

West Gippsland Region ...... 36

Port Phillip and Region ...... 38 5. Results ...... 40

Soil salinity vs “flagships” & “biolinks” ...... 40

Salinity province identification ...... 45

Salinity Provinces in Victorian Bioregions – 2011 v

Environmental asset areas ...... 62

Environmental asset areas vs salinity provinces ...... 62

Groundwater trends for salinity provinces ...... 72

Salt export risks for priority provinces ...... 74 6. Conclusions ...... 75

Priority salinity provinces ...... 75 7. Recommendations ...... 76 8. References ...... 77

Salinity management plan references ...... 77

Other references ...... 78 9. Appendices ...... 81

Appendix A – Map outputs ...... 81

Appendix B – Example bore hydrographs ...... 85

List of Tables

Table 1. Salinity “Hot Spots” identified in Corangamite Salinity Forum (1992) ...... 14 Table 2. Target (priority) areas and rankings ...... 15 Table 3. Target areas and estimated salinity (ha) ...... 15 Table 4. Glenelg Salinity Region – salt affected land ...... 16 Table 5. Notable salt-affected areas of the Glenelg Salinity Region...... 17 Table 6. Priority Land Management Units ...... 19 Table 7. Investment classification of Wimmera GFS ...... 20 Table 8. GFS identified as having Medium to Major Asset Threat and the capacity to influence ...... 20 Table 9. Area of land affected by salinity in the Wimmera SAP ...... 21 Table 10. Dryland salt-affected areas, Nangiloc-Colignan, 1989 ...... 23 Table 11. Salinity impacts on specified environmental sites in Sunraysia ...... 24 Table 12. Priority rankings of Mallee RRMU ...... 26 Table 13. Goulburn-Broken Dryland Land Management Units (after McGowan International 1988) ...... 31 Table 14. Number of sites and total areas of salinity discharge points by Catchment Management Unit .34 Table 15. Identified priority areas in the North East Region ...... 35 Table 16. PP&WPCMA - Framework for risk to economic values of agriculture from salinity ...... 38 Table 17. Mapped dryland salinity extent in “Flagships” ...... 40 Table 17. Mapped dryland salinity extent in “Flagships” continued ...... 41 Table 18. Mapped dryland salinity extent in “Biolinks” ...... 44

Salinity Provinces in Victorian Bioregions – 2011 vi

Table 19. Corangamite Salinity Provinces ...... 46 Table 19. Corangamite Salinity Provinces continued ...... 47 Table 20. Glenelg-Hopkins Salinity Provinces ...... 48 Table 21. Wimmera Salinity Provinces ...... 50 Table 22. Mallee Salinity Provinces ...... 51 Table 23. North Central Salinity Provinces: Avon-Richardson catchment ...... 52 Table 24. North Central Salinity Provinces: Avoca catchment ...... 52 Table 25. North Central Salinity Provinces: Loddon catchment ...... 53 Table 26. North Central Salinity Provinces: Campaspe catchment ...... 54 Table 27. Goulburn-Broken Salinity Provinces: Goulburn catchment ...... 55 Table 28. Goulburn-Broken Salinity Provinces: Broken catchment ...... 56 Table 29. North East Salinity Provinces ...... 57 Table 30. Salinity Provinces #1 ...... 58 Table 31. West Gippsland Salinity Provinces #1 ...... 59 Table 32. and Western Port Salinity Provinces ...... 61 Table 33. List of Environmental Asset Areas (“Flagships” and “Biolinks”) ...... 62 Table 34. Intersection of Salinity Provinces with priority biodiversity regions (“Flagships”) ...... 63 Table 35. Intersection of Salinity Provinces with strategic linkage regions (“Biolinks”) ...... 67 Table 36. Preliminary list of priority Salinity Provinces (based on Tables 34 and 35)...... 70 Table 37. Listing of typical groundwater trends (or range) for each priority salinity province...... 72 Table 37. Listing of typical groundwater trends (or range) for each priority salinity province (cont.) ...... 73

Salinity Provinces in Victorian Bioregions – 2011 vii

1. Introduction This Technical report is the final milestone for the 2010-2011 Statewide Salinity Research and Support Project funded by the Department of Sustainability and Environment. It directly addresses Objective 1 of the Project Plan by reporting on the current and future salinity risk of environmental asset areas, defined as “Flagships” and “Biolinks” in the Land and Biodiversity White Paper (2010). It contains important information required by DSE to meet reporting requirements for the Natural Resources Management Plan and will inform future investment targeted at managing salinity across Victoria.

DSE Land Health Program invests in regional and State-wide actions to protect environmental asset areas and the resilience of ecosystems where they are threatened by dryland salinity and soil degradation. Investment from the Land Health Program is based on the understanding that: “the condition of our land and waterways will improve as the impact of salinity and soil degradation is reduced” (Growing Victoria Together).

Over recent years, investment in soil and salinity has shifted from a threat-based to an asset-based approach that recognises salinity must be addressed in conjunction with other land, water and biodiversity issues rather than in isolation. To achieve this, DSE Land Health Program investment is now targeted towards the long-term protection of high value natural resource assets threatened by soil degradation including dryland salinity.

Project Outcome By 30 June 2011, there will be improved information and knowledge of the current and future groundwater and salinity threats to instructively inform the management of identified high priority environmental assets and meet Victorian DSE policy obligations. Project Background A draft dryland salinity position paper by Shayne Annett (May 2009), then of DSE, concluded that while the threat to natural assets from dryland salinity is not expected to reach levels predicted in the late 1990s, the threat has not disappeared. Despite the downgrading of the dryland salinity threat during the dry 1997-2009 period, it remains a serious ongoing threat to priority assets including land, waterways and biodiversity. This may be reinforced by subsequent impacts of the current wet year, which could serve as a timely and needed reminder that salinity is still a significant environmental issue. Annett (2009) further concluded that future investment in dryland salinity should be based on a rigorous and well targeted analysis of the likelihood and consequence of dryland salinity threatening natural assets. It should not be treated as a special case, but as one of a range of threats that exist across Victorian landscapes. Dryland salinity management should be part of a comprehensive catchment management approach.

In keeping with this philosophy and within the Hydrogeological Support for DSE Statewide Dryland Salinity program, FFSR propose to maintain a well-targeted watching brief on groundwater levels, groundwater salinities, soil salinity, and salt export. This watching brief will be strongly aligned to significantly threatened high priority NRM assets and the ecosystems they provide, particularly those within environmental asset areas (defined as Flagships and Biolinks in the White Paper for Land and Biodiversity, “Securing our Natural Future”, DSE, November 2009). Importantly also, it will be aligned to the White Paper for Climate Change by analysing climate impacts on groundwater and base flow, and assessing salinity risk based on long-term climate forecasts.

The three main components of the work in 2010-2011 are: (i) NRM Plan reporting of current and future salinity risks to high priority NRM assets, particularly those in environmental asset areas (as defined in the White Paper for Land and Biodiversity, DSE, 2009), (ii) targeted assessment of the impacts on watertables of the wet conditions in 2010, and (iii) Continued collection and management of groundwater and soil salinity data for the State.

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An additional component being completed and closely related to this report is a report on the findings from salinity remapping of six representative salt-affected sub-catchments in 2008 and 2009. The report is entitled: “Remapping soil salinity in Victoria in 2008 and 2009 to identify changes in its extent and severity since the late 1980s” by Clark (2011, in draft). Project Objectives This report provides the descriptive component of objective 1 (below) and relates to the major spatial analysis and mapping component which is the development of a ‘Salinity Provinces’ layer for the state. This completes one of the objectives of the 2010/11 statewide dryland salinity project. The other objectives are reported elsewhere (as indicated in brackets). 1) To determine and advise on the current and future risk of dryland salinity, either in or affecting identified priority assets in environmental asset areas. 2) To determine the impact of wet conditions in 2010 on watertables in the Goulburn-Broken and North Central CMA regions (Cheng, 2011 – in draft). 3) Review Victoria’s dryland salinity bore network monitoring program (Hekmeijer and Cook 2011, in progress). 4) Maintain currency and integrity of Victoria’s dryland soil salinity and groundwater databases, and data collection from the statewide salinity bore network (monitoring and data management). 5) Improve dryland salinity information on the VRO website (Done, May 2011 – Clark and Brown). 6) Meet objectives of linked project, CMI 103784, “New hydrological tools to assess catchment behaviour” (collaborative project with Tim Peterson at University of ), as follows:- a) strengthen the validity of catchment resilience theories with an emphasis on groundwater; b) develop new statistical methods for mapping and forecasting groundwater data which can identify the crossing of thresholds and model change in resilience; c) forecast and map groundwater elevation and resilience in catchments. 7) Provide all necessary project documentation b) Meet all FFSR quality assurance standards c) Meet all project closure requirements

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2. Method Project scope DSE require reporting with map outputs on the present salinity status of environmental asset areas to feed into the Natural Resources Management (NRM) Plan and Victorian Investment Framework (VIF). The development of salinity provinces and their coincidence with the defined ‘Flagships’ and ‘Biolinks’ are to provide a measure of current extent of salinity, future salinity risk (or likelihood of change) and resilience of designated assets, particularly in defined asset areas for environmental protection (defined as “Flagships” and “Biolinks” in Land and Biodiversity White Paper 2010). The scope also sought a qualified statement on the ability to intervene where there is a significant threat to such areas. Wherever there is poor or insufficient information to form a conclusion as to future threat, resilience or ability to intervene, this needs to be stated together with any knowledge gaps. Outline of approach The comprehensive GIS soil salinity layer provides the spatial distribution of nearly all salt-affected soil in Victorian dryland regions (Clark and Harvey 2008). This, together with knowledge gained from past salinity investigations and improved understanding of climate impacts, provides an excellent basis for understanding current extent and risk of salinity, and the salinity hazard areas, or Salinity Provinces (see introduction of salinity province concept in Section 3). This is enhanced by groundwater flow systems (GFS) knowledge which, along with groundwater hydrograph and salt export risk assessments, will permit predictions of risks and consequences to priority assets, particularly those in environmental asset areas (as defined in Land and Biodiversity White Paper 2010). Conclusions about intervention feasibility will be reliant upon GFS knowledge in relation to system behaviour, responsiveness and resilience, the nature and scale of the threat, and knowledge of appropriate treatment options and their likely effectiveness at treating either cause or effect.

Method The method described here is slightly modified from the original method reported in the Project Plan (Reid 2010). It has a greater emphasis on the identification, mapping and prioritisation of Salinity Provinces, which are then regarded as fundamental to effectively addressing the above defined scope.

Task 1. Review of regional salinity plans and past salinity risk assessments Review salinity plans, catchment strategies and associated documents of the past two decades to summarise what were regarded at the time to be priority salinity areas. Use these to help identify / validate and prioritise salinity provinces.

Task 2. Soil salinity (current extent and severity) and GFS cover Produce updated soil salinity maps (for the State and 3 large regional maps) from the Soil Salinity Database held in the Corporate Spatial Data Library. Intersect these with the “Flagships and Biolinks” layer, also in the Corporate Library. Produce tables with calculated salinity class areas for each “Flagship” and “Biolink” area. Also overlay the current soil salinity layer on a full GFS / geology cover for the State together with a geological fault cover from Geoscience Victoria.

Task 3. Salinity Provinces This task forms the main basis and component of this salinity risk assessment.

Define the concept of salinity provinces, then identify, define and map salinity provinces for the whole State of Victoria, including irrigation areas. This will be based largely on Tasks 1 and 2, including GFS setting (could comprise one or more influential GFS) and geological structure (also see Section 3). The Victorian Dryland Salinity Bore Network (DSBN) cover will also be used to validate provinces and refine province boundaries.

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Intersect the new Victorian Salinity Provinces map with the “Flagships” and “Biolinks” layer to construct a preliminary list of priority Salinity Provinces, using criteria of a 30% or greater intersection of Salinity Provinces with “Flagships” and/or “Biolinks”.

Task 4. Hydrograph assessment Overlay the Dryland Salinity Bore Network (DSBN), State Observation Bore Network (SOBN) and Salinity Province layer onto the “Flagships and Biolinks” layer. Use the key DSBN bores from Task 1, above, and identify relevant SOBN bores with good monitoring record (preferably greater than 10 years of uninterrupted record). Undertake analysis of trends and recharge using the hydrographs of the identified suitable bores. This analysis will assess trend and recharge occurrence against climate (particularly focussing on pre- and post-1997) and groundwater flow system, to help assess likelihood of expansion or regression of salinity, as well as groundwater responsiveness to climate and consider ability to intervene.

This task will be partly informed by work on Tasks 1 and 3. For analysis of groundwater trends, it will adopt the Hydrograph Analysis: Rainfall and Time Trends (HARTT) approach which was developed by Ferdowsian et al (2001). This method can differentiate between the effect of rainfall fluctuations and the underlying trend of groundwater level over time. Rainfall is represented as an accumulation of deviations from average rainfall, and the lag between rainfall and its impact on groundwater is explicitly represented.

Task 5. Salt export risk assessment Conduct a literature and data search to identify streams/catchments with historically high salt export and/or salinities. Identify areas where these intersect with and/or affect “Flagships” and “Biolinks”.

Task 6. Complete final products and conclusions Integration of results from Tasks 1 to 5 to identify high priority salinity hazard areas in terms of (a) current extent and severity, and (b) risk of increase in extent/severity. Conduct preliminary assessment of feasibility to intervene (with levels of confidence) in identified high priority hazard areas based on integration of results from Tasks 1 to 5, together with conceptual interpretation of groundwater flow system responses. Products

Maps • Current extent and severity of soil salinity in “Flagship” and “Biolink” areas. Produce Statewide and large regional maps (3 for State). From Task 2. • Current extent and severity of soil salinity with GFS / geology cover plus major geological faults. From Task 2. • Statewide maps of (a) Salinity Provinces intersected with soil salinity, GFS/geology and major geological faults, (b) Salinity Provinces intersected with soil salinity and “Flagship” and “Biolink” areas, and (c) Salinity Provinces intersected with soil salinity and the DSBN. From Task 2. • High future salinity hazard areas in “Flagships”/”Biolinks”. (Premise:- Rating of salinity hazard will be based on intersection with salinity provinces, the current extent/severity of soil salinity and salt export in or affecting “Flagships”/”Biolinks”, the risk of future increase in either of these. High ratings will tend to be those already significantly impacting or threatening assets. Areas with currently minor to negligible salinity extent/severity are unlikely to attract a high hazard rating. From Tasks 1 to 5.

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3. Salinity Provinces Introduction The concept and framework of salinity provinces was first introduced in 1986 (DWR) with the aim of improving understanding of physical control options. It has been re-visited here in order to further improve governance and management of salinity. This improved framework will enable better targeting of risk or hazard assessment against high value assets and form a user friendly reference base for describing salinity occurrence and risk in Victoria. It makes use of past salinity management plans, catchment strategies and associated documents, as well as the Statewide GIS soil salinity layer, the Statewide GIS 1:250,000 groundwater flow system (GFS) layer and, to some degree, the Geoscience Victoria geological structure layer. It assumes that the knowledge of historic and current extent and severity of salinity is well represented by the soil salinity layer and well documented by past investigations and salinity management plans. It also assumes that, based on observations of salinity in response to dry and wet climate cycles over the past 40 years, the majority of salinity occurrences will tend to cyclically worsen or improve within the identified salinity provinces. Definition of salinity province A geographically discrete salinity impacted area with low to high salinity hazard rating; an area which possesses a discrete geographic concentration or incidence of recorded land and stream salinisation (from primary or secondary causes), the majority of which can be explained by a particular landscape setting or groundwater process, but which could include more than one GFS and could be defined and/or controlled by major geological structure. Background Findings in recent years (incl. Gill 2004, Cheng et al 2006, Mudd et al 2006; Reid et al 2006; Hekmeijer et al 2008; Clark and Harvey 2008, Dahlhaus et al 2008; Reid et al 2009; Dahlhaus et al 2010; Reid 2010), have provided a range of new knowledge about groundwater behaviour, GFS, salinity occurrence and salinity risk in Victoria. Conclusions from these works include the following: • Salinity extent and severity is strongly cyclical, expanding and contracting periodically. • Salinity may not in the medium-long term spread much in extent beyond existing mapped or recorded salt-affected areas, or not increase much in severity beyond what has been experienced already (NB. this assumes that longer-term drier climate forecasts are correct, and that environmental care remains paramount and well observed for all land uses). • Climate has the larger overall influence on changes in groundwater levels and salinity but land use also has a major influence, particularly where it directly interacts with primary (natural) discharge areas, causes or repairs secondary saline discharge areas or significantly modifies recharge in hazardous areas. • In some cases (e.g. parts of the Corangamite region; Dahlhaus et al 2008, Dahlhaus et al 2010), broad-scale clearing of native vegetation cannot be demonstrably linked to salinity risk, so that other causes or factors, including aspects of climate and geology, or different aspects of land use, are required to explain the cause of salinity or salinity risk. • The incidence of primary salinity as a percentage of total salt-affected area in Victoria is greater than previously thought or acknowledged. This includes emerging evidence suggesting that a significant proportion of discharge areas previously thought to be secondary and due to increased recharge, are instead primary discharge areas with secondary degradation resulting from direct land use change impacts. • Most salinity occurrences are the result of hydrologic interactions with or across more than one GFS. • A particular type of GFS that may contain common occurrences of salinity will not necessarily be a universal hazard. A number of other factors influence whether that GFS, in any particular area,

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poses a hazard. These include interaction with other GFS, geological structure, geomorphology, climate and land use. This was probably implied in previous work (e.g. Coram et al 2001; Walker et al 2003) but is expressed specifically here to help clarify the way in which salinity processes involving GFS should be defined; and • Geological structure (including faults, down-faulted blocks, major folds, geological contacts, volcanic intrusions) are considered to exert a commonplace and significant control on the location of groundwater discharge and salinity occurrence. Furthermore, where this is the case, it is considered likely that the discharge area supports, or used to support, a dependent native ecosystem and thus is, or was, a groundwater dependent ecosystem, or GDE.

The process of identifying salinity provinces begins with a review of salinity plans, catchment strategies and associated documents of the past two decades to summarise what were regarded at the time to be priority salinity areas. The salinity provinces and their later priority rating will be guided by this, but their final definition will be resolved by assessment of recorded or known salinity occurrence and hazard against GFS setting (could comprise one or more influential GFS) and geological structure.

Based on the scope and instructions provided by DSE, the highest priority for investment will apply to those salinity provinces satisfying the following three criteria: • intersect priority biodiverse areas, especially formally recognised high value environmental assets within these areas; • the contained salinity hazards, through secondary salinity processes have caused, or are predicted to continue to cause, significant harmful consequences to high value assets; • intervention or mitigation of the threatening salinity hazards is considered feasible and to offer good return for investment in protection or enhancement of the threatened environmental asset.

The salinity provinces are defined across the whole State and given a preliminary low or high priority rating based partly on the currently mapped salinity extent and severity and partly on how they rated (or not) in salinity plans. These are then overlayed onto the Statewide cover of environmental asset areas (i.e. priority biodiverse regions, or “Flagships” and strategic linking regions, or “Biolinks”, as defined and presented in the Land and Biodiversity White Paper, DSE 2010). A preliminary list of priority salinity provinces is then compiled (Table 36) based on 30% or greater intersection of a high priority salinity province with a “Flagship” and/or “Biolink”. This includes the proviso that the intersected portion comprises significant recorded salinity and that this salinity occurrence is not known to be mostly or all primary in origin (for example, the Raak Plains, which intersects the Mallee “Flagship”, is well recognised as an area of natural salinity; e.g. Macumber 1991). By definition, all provinces should contain some recorded, known or suspected incidences of salinity and will have low to high salinity hazard ratings. The priority for investment for a major proportion of provinces may later be found to be low for any of several possible reasons, including: • they do not intersect significantly (or at all) with environmental asset areas; • feasibility to successfully intervene is poor, or intervention has a poor rate of return; and • there is sufficient knowledge to indicate a low future threat, or low impact, or one that is easy to manage without need for government investment.

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4. Priority areas identified in regional salinity documents The following CMA region summaries of previously identified priority salinity areas are based on a review of salinity management plans (SMPs), regional catchment strategies (RCSs) and associated documents. Corangamite Region

“Restoring the balance – a strategy for managing salinity in the Corangamite Salinity Region” (Corangamite Salinity Forum 1992) This original plan for managing salinity in the Corangamite region identified 11 worst affected areas or “hot spots” for prioritising action. These are described below in Table 1 and were based on:-

• The amount of salt affected land. • How quickly salinity was expanding. • The net value of production. • The effect of salinity on rivers, streams, , flora and fauna. • The effect of salinity on surrounding areas. • The effect of salinity on the urban community.

Table 1. Salinity “Hot Spots” identified in Corangamite Salinity Forum (1992) Salinity Hot Spot Approx. total area (ha) & Description mapped salinity area as at 1992 (ha) 1. Hill country of the Upper Total area: 23,000 Extends from the granite hills of Pittong and Salinity area: ?? Linton eastwards and south eastwards to the sedimentary hills around Cape Clear, Illabarook and Rokewood. 2. Granite rises at Lismore 3,000 Granite country centred around the 350 township of Lismore. 3. Moriac and 24,000 Between the foothills of the Otway Ranges 4. 1,100 and the valley, stretching from Barwon Downs to Moriac. 5. The Heytesbury Settlement 47,000 Centred on the town of Simpson to the 400 west of the Otway Ranges. 6. Basalt plains 52,000 Bounded by the towns of Rokewood, 500 Cressy, Wingeel and Shelford. and dune systems at: 18,000 -Eurack, Leslie Manor and 7. Beeac-Eurack, 6,500 (60% estimated to be Winchelsea. Includes naturally saline 8. Leslie Manor, and natural) and dunes, or lunettes. 9. Winchelsea 10. Deans and Barongarook 11,000 South of Colac. The Deans catchment Creek catchments 310 (3,500 ha) drains the hills of Barongarook West and the flats of Larpent. The Barongarook catchment is 7,500 ha. Both catchments drain into . 11. Upper Maribyrnong 45,000 Bounded by Sunbury, Kilmore, Riddells catchment (Note: this is now in 450 Creek and Wallan. the Port Phillip and Western Port CMA region)

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Corangamite Salinity Action Plan 2005-2008 (Nicholson et al 2006) This plan identified twelve (12) salinity target (priority) areas using an asset based approach. The 12 areas encompass more than an estimated 80% of the primary salting, 87% of the saline wetlands and 63% of the secondary salting in the Corangamite CMA Region. The plan described the assets threatened by salinity, the salinity trends and predictions, management options and impact of proposed treatments for each target area in the SAP.

Table 2. Target (priority) areas and rankings (after Nicholson et al 2006) Rank Market ranking (based on Non-market ranking Overall ranking Benefit-Cost Ratio)* 1 Lismore-Derrinallum Lake Corangamite 2 Murdeduke Morrisons Sheoaks Morrisons Sheoaks 3 Modewarre Upper West Moorabool Upper West Moorabool 4 Morrisons Sheoaks Colac-Eurack Colac-Eurack 5 Pittong - Geelong-Lake Connewarre 6 Illabarook Pittong Lismore-Derrinallum 7 Lake Corangamite Illabarook Illabarook 8 Colac-Eurack Lismore-Derrinallum Pittong 9 Geelong-Lake Connewarre Modewarre Murdeduke 10 Warncoort Murdeduke Modewarre 11 Warncoort Warncoort 12 Lara Lara *No BCR determinations were made for the Upper West Moorabool or Lara areas

Table 3. Target areas and estimated salinity (ha) (after Nicholson et al 2006) Target area Total area Primary Secondary Saline (in overall ranking order) (ha) salinity (ha) salinity (ha) wetlands (ha) 1. Lake Corangamite 88,894 1,116 2,413 28,883 2. Morrisons Sheoaks 22,368 23 40 3. Upper West Moorabool 29,045 15 4. Colac-Eurack 34,367 1,410 797 4,129 5. Geelong-Lake Connewarre 12,922 2,307 64 3,104 6. Lismore-Derrinallum 16,443 1,466 305 25 7. Illabarook 20,492 366 8. Pittong 6,300 378 9. Murdeduke 14,959 243 381 2,091 10. Modewarre 23,675 270 160 681 11. Warncoort 6,826 385 111 13 12. Lara 3,418 143 89 949 Total in SAP target areas 279,709 7,363 5,120 39,874 Total in CCMA area 9,182 8,084 45,731

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Glenelg-Hopkins Region

Salt assault! – the Glenelg Region Salinity Strategy (Glenelg Salinity Forum 1993) Table 4 shows the area of agricultural land and estimated salt-affected area for each Land Management Unit (LMU) as defined in Glenelg Salinity Forum (1993).

Table 4. Glenelg Salinity Region – salt affected land (after Glenelg Salinity Forum 1993) Land Management Unit (LMU) Area of agricultural Estimated salt- Reliability of land (ha) affected area (ha) estimate 1a. Dundas Tablelands West 186,300 3,020 2 1b. Dundas Tablelands East 148,900 6,860 2 2. Grampians 6,700 <100 3 3. Grampians Slopes 6,300 200 2 4. Granite 35,300 300 2 5. Merino Tablelands 91,700 1700 3 6. South West Sands 214,300 860 3 7. Weathered Limestone 126,800 <100 3 8a. Sedimentary Rises 96,500 530 1 8b. Steep Sedimentary Hills 20,100 40 1 9. Southern Alluvial Plains 42,600 150 3 10a. Volcanic Plains 760,600 3120 2 10b. Stony Rises and Scoria Cones 153,400 800 3 11. Northern Alluvial Plains 101,600 2050 1 12. Tertiary Sands 19,600 140 3 TOTAL 2010000 19970 NOTE: Reliability of estimates are as follows:- Estimate based on detailed survey including aerial photograph interpretation with extensive ground truthing and mapping. Estimate based on extrapolation from surveyed areas where the initial sample was less than 20% of the LMU area and/or extrapolation has been extended over an extensive range. Estimate based on anecdotal information and observations of field staff using available information.

The following areas listed in Table 5 were highlighted by the Glenelg Salinity Forum (1993) as being of most concern at the time.

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Table 5. Notable salt-affected areas of the Glenelg Salinity Region (after Glenelg Salinity Forum 1993). Area Key affected Land Management Comments Units (refer also Table 4) Upper Hopkins Catchment LMU 11 most severely affected. Salinity distribution mapped in detail Other affected LMUs are 4, 8a, 8b by Sturmfels (1988) and 10a. Dundas Tablelands LMUs 1a and 1b Aerial photograph interpretation in 1986 yielded estimate of 9880 ha of visible salting (~3% of agricultural land) Glenthompson LMU 4 Dixon (1989) mapped 670 ha of salinity in a sub-catchment south of Glenthompson. This amounted to about 15% of the sub-catchment and was considered at the time to be representative of the wider area. Victoria Valley LMUs 2, 3, 4 and 11 Estimate of 1200 ha of salt-affected land based on landholder survey Volcanic Plains and Stony Rises LMUs 10a and 10b Dunn (1991) estimated that 130 ha, or 4.5% of a 2400 ha area of plains adjacent to stony rises, was salt- affected. Other surveys indicated that groundwater readily discharges from margins of stony rises.

Other areas identified in Glenelg Salinity Forum (1993) as having observable salinity problems are:- • Tatyoon-Rossbridge • Carngham-Chepstowe • Dergholm • Digby • Lake Fyans-Mt. William Creek • Pura Pura-Nerrin Nerrin • Strathkellar-Moutajup • Hensley Park • Trawalla • Woorndoo-Chatsworth

For each of these other areas, no reliable information was available at the time concerning relative area of salt-affected land.

1:250,000 scale Groundwater Flow Systems map (Dahlhaus 2002) Based on concentration/extent of mapped salinity on the 1:250,000 scale GFS map (Dahlhaus 2002), the following areas stand out as the most salt-affected:

• Merino Tablelands • West Dundas Tablelands • East Dundas Tablelands • Hamilton Volcanic Plains • Mortlake Volcanic Plains • Late Phase Volcanics north-east of Mortlake • Woorndoo • West of Woorndoo (deeply weathered granite and other Palaeozoic rocks) • Beaufort (fractured Palaeozoic rocks and granites) • Ararat and south (mainly fractured Palaeozoic rocks and fractured basalts) • Volcanic Plains between Grampians and south of Ararat • Victoria Valley (Grampians) weathered granite and alluvium

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Wimmera Region

Wimmera Catchment Salinity Management Plan – Draft (Wimmera CCG 1992a) In 1992, approximately 20,000 ha of salt-affected land had been identified, while some areas in the north of the catchment had yet to be assessed. This figure includes naturally salt affected areas. The draft plan stated that ‘despite the high estimate of salt-affected land, it was salting or saline degradation of the surface water that had the greatest impact on the environment and community in the Wimmera catchment’.

The majority of salinity in the catchment is located in low lying land next to the between Drung and and around the chains of lakes in the south west of the catchment (i.e. Douglas Depression and Edenhope areas). The draft plan reported that some of this area was known to be saline before the mid 1880s when it was first settled. Based on the hydrogeological setting, it is highly probable that the majority of the salinity in these areas is due to natural causes.

As at 1992, there was 2,580 ha of salt affected land mapped in the upper catchment but it was regarded to be not as severe as in the lower catchment.

Up to 1992, an average of 85,000 tonnes of salt entered the Wimmera catchment surface waters each year. This figure did not include salt imported from the catchment, or groundwater intrusion into the Wimmera River downstream of Lochiel. The highest recorded salt exporting sub-catchment was the Mt. William-Pleasant Creek catchment, which was producing an average of 21,000 tonnes of salt per year.

Between Horsham and Lochiel, the average salt load in the Wimmera River was increasing from 17,200 to 31,000 tonnes per year, an increase of 80%, while the flow only increased about 7%. The majority of this salt load increase is due to groundwater intrusion. Downstream of Lochiel, there was little flow or salinity data, but it was considered possible that the river could receive around 30,000 tonnes of salt per year from groundwater seepage, which would make it the highest salt load entering the river over any reach.

The main aim of the Wimmera SMP was to improve water quality. It did not generally specify particular localities or geographic areas for priority management action to achieve this. Instead, it employed a system of 21 Land Management Units (LMUs), which were defined on the basis of physiography and geology. From this it identified nine (9) priority LMUs for immediate works using the following criteria: • Total amount of recharge. • Impact on water quality. • Impact on agricultural productivity. • Impact on the environment. • Impact on areas outside the Wimmera Catchment. • Likely impact of control measures on improving water quality in the short term.

The nine priority LMUs are listed in Table 6 together with their priority rating, general location and estimated salt-affected land.

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Table 6. Priority Land Management Units (after Wimmera CCG 1992a) LMU LMU Name Priority General Locality Description Estimated salt- No. Rating affected land (ha) 1 Uplands Alluvial Plains Very high Upper catchment; upland valleys of 696 Concongella, Wattle, Six Mile, Greens and Mt. Cole Creeks. 2 Grampians Alluvial Plains Very high Between Moyston, Pomonal, Lake 1415 Lonsdale and Bellellen; dissected by Mt. William Creek. 5 Granitic Terrain High Mt. Cole, Ben Nevis, Langhi Ghiran, 111 Black Range south of Stawell, Great Western, Mt. Buangor, and Moyston. 6 Metamorphic Ridges High Pyrenees Ranges and Mt. Ararat area; 9 adjacent to sedimentary rises. 7 Sedimentary Rises High Throughout upper catchment (e.g. 333 Landsborough and Moyston). 10 Grampians Colluvium High Margins of the Grampians Ranges 23 13 Mallee Plains High High priority for this LMU is the area 3103 (+) immediately west of the Wimmera River, between the Little Desert National Park and Lake Hindmarsh. 14 Undulating Alluvial Plains High South of the Wimmera River, between 6528 the river and the Grampians/Black Ranges, including the Mackenzie Creek system and Laharum. 15 Flat Grey Plains Very high Margins forming the natural floodplain of 1714 the Wimmera River and .

Wimmera River Integrated Catchment Management Strategy (Wimmera CCG 1992b) The Wimmera River is a seriously degraded river with salinity being a major factor. Most of its entire length is affected to some degree by salinity. At low flows, the level of salinity in some pools in the lower Wimmera River is greater than that of sea water, seriously affecting aquatic life. In 1992, 50 km of the 130 km of public land frontage upstream of Horsham showed signs of salinity and many upper catchment tributaries, especially Mt. Cole, Six Mile and Heifer Station Creeks, were highly saline.

Wimmera Regional Salinity Action Plan (SAP) 2005 – 2010 (Wimmera CMA 2005). This plan has a strong GFS focus but mostly does not appear to define worst-affected or highest risk areas, or clearly define salinity priorities in geographical terms, except for the Wimmera River, Lake Hindmarsh, the Wimmera River terminal lakes and Millicent Basin wetlands.

Priority Areas / Assets (see also Tables 7, 8 and 9, below):- • Wimmera River • Lake Hindmarsh • and other terminal lakes of Wimmera River Basin • Millicent Coast Basin (Edenhope area)

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Table 7. Investment classification of Wimmera GFS (“incl. Priority GFS”) (after Wimmera CMA 2005) Investment GFS Rationale Classification Implementation - Local flow systems in deeply These GFSs pose a major threat to key assets; weathered granite (low relief) management options are relatively well understood - Local flow systems in highly and have the potential to influence the system in the fractured rocks short term. - Local and intermediate flow While there are still some R&D questions relating to systems in deeply weathered these systems they would be the focus for public fractured rock. investment in implementation initiatives. - Regional flow systems in Parilla Sand – Millicent Coast Basin Research & - Regional flow systems in Parilla While these GFS pose significant threats to key Development Sands assets, there is limited capacity of current (R&D) - Local flow systems in weathered management options to influence these systems. If granite (high relief) assets are to be protected in the long term, - Intermediate flow systems in management options will need to be developed for alluvial plains these GFS. Therefore these systems will be the - Local flow systems in colluvium focus for public investment in R&D. (Grampians Sandstone) Co-investment - Local flow systems in sand dunes These systems pose limited threats to public assets, (Lowan Sands) however, available management options could have - Local flow systems in Woorinen a significant influence in the very short term. sediments Public investment should focus on providing - Intermediate flow systems in information and initiatives to facilitate private fractured rocks investment for private gain. These systems provide the potential for quick benefits for broader salinity.

Table 8. GFS identified as having Medium to Major Asset Threat and the capacity to influence (based on Table 33 in Wimmera CMA 2005) GFS Threat to assets Capacity to Investment influence Classification Regional flow systems in Parilla Sand Major Limited Research & Development (R&D) Local flow systems in deeply weathered granites Major Medium Implementation – low relief Local flow systems in highly fractured rocks Major Medium to Implementation significant Local and intermediate flow systems in deeply Major (but limited Medium Implementation weathered fractured rocks threat to agric land) Regional flow systems in Parilla Sand – Millicent Medium to Major Medium Implementation & Coast Basin R&D Intermediate flow systems in fractured rocks Medium Limited Co-investment Intermediate flow systems in alluvial plains Medium Medium R&D

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Table 9. Area of land affected by salinity in the Wimmera SAP (after Wimmera CMA 2005) Groundwater Flow System Area Affected by Salinity (ha) Low Moderate High Total Intermediate flow systems in alluvial plains 2,951 1,281 263 4,495 Intermediate flow systems in fractured rocks (sedimentary and 128 49 0 177 metamorphic) Local and intermediate flow systems in deeply weathered fractured 45 131 4 179 rocks (sedimentary and metamorphic) Local flow systems in colluvium (Grampians Sandstone) 6 0 0 6 Local flow systems in deeply weathered granite (low relief) 25 10 0 35 Local flow systems in highly fractured rocks (sedimentary and 15 0 0 15 metamorphic) Local flow systems in sand dunes (Lowan Formation) 1,816 280 1,204 3,301 Local flow systems in weathered granite (high relief) 8 0 0 8 Regional flow systems in limestone overlain by local flow systems 349 0 4 353 in Woorinen sediments Regional flow systems in Parilla Sands overlain by local flow 6,109 807 2,508 9,423 systems in Woorinen sediments Groundwater Flow Systems - No Data 1,948 208 1,563 3,719 Total 13,399 2,765 5,547 21,711

Note: the shaded GFS above are those which have been classified for implementation investment in the Wimmera SAP, although for the regional flow systems in Parilla Sands, that applies only to the Millicent Coast Basin (refer also to Tables 7 and 8).

It appears from Table 9 that agricultural assets in the Wimmera are given equal weighting to environmental and other assets, regardless of area impacted. Therefore, it is problematic to reconcile some of the above salt-affected areas with the threats to assets ratings in the preceding table. For example, local flow systems in highly fractured rocks is identified as having a “major threat” to assets while it apparently only affects a total of 15 ha (all of which is classed as low severity). Similarly, for local flow systems in deeply weathered granite (low relief), an asset threat classification of ‘Major’ does not seem consistent with an affected area of only 35 ha, of which 25 ha is low severity. In contrast, intermediate flow systems in alluvial plains have been given an asset threat classification of medium, yet have recorded a total mapped salinity area of 4,495 ha, of which 1,544 ha is moderate to high severity.

A potential issue with the broad GFS approach used in this case is that the apparent intersection of GFS with mapped salinity is based on intersection with the mapped outcrop of GFS or its associated geology, the point being that intersection of salinity with a particular GFS outcrop does not necessarily mean that that GFS is the main or only driver of salinity expressed at that particular location. For example, salinity mapped as occurring on a local or intermediate alluvial plain GFS, especially where thinly developed, may in fact be predominantly influenced by an adjacent/underlying fractured or weathered bedrock GFS.

In conclusion, it is quite difficult to use this generic GFS approach of Wimmera CMA (2005) to identify priority salinity areas, and so in this respect, more attention will be given to the earlier Wimmera SMP documents (Wimmera CCG 1992a and 1992b).

Salinity Provinces in Victorian Bioregions – 2011 21

Based on an approximate interpretation of the current mapped salinity concentration/extent, the following areas could be priority salinity areas: • Lower Wimmera • Edenhope area • Telopea Downs (mostly primary salinity) • Lake Hindmarsh • Dimboola-Jeparit (west side of Wimmera River) • NE Wimmera (east of Warracknabeal) • Horsham • Natimuk (northern Douglas Depression) • Southern Douglas Depression (west of Toolondo) • Upper Wimmera • Stawell • Great Western • Elmhurst • Navarre These accord quite well with areas mentioned in Wimmera CCG (1992a and 1992b).

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Mallee Region

Nangiloc-Colignan Draft Salinity Management Plan (Nangiloc-Colignan CSWG 1991) The Nangiloc-Colignan sub-region covers 39,000 ha, about 28,200 ha of which, at the time, were used for dryland farming while 5,300 ha were used for irrigation. Public land occupied approximately 5,500 ha.

At the time of the draft plan, approximately 1,000 ha of irrigated property were suffering reduced incomes due to waterlogging and salinity and the lack of access to drainage disposal. Large tracts of dryland farm were salt-affected due partly to natural causes and partly to land clearing, channel seepage and seepage from adjacent irrigation areas. Table 10 lists dryland salt-affected areas with estimates of their size in 1989 and original natural size. The figures show that an estimated additional 2,255 ha of dryland became saline between the commencement of irrigation in the early 1920s, and 1989. Two major wetlands, the Karadoc and Bullock Swamps (respectively 1,400 and 340 ha), became severely degraded, suffering as a result of rising regional groundwater levels, drainage water disposal and changes to flooding cycles.

Table 10. Dryland salt-affected areas, Nangiloc-Colignan, 1989 (after Nangiloc-Colignan CSWG 1991) Dryland Site Estimated natural size Estimated size in 1989 Increase in area (ha) (ha) (ha) Yatpool Basin 890 950 60 Carwarp West Basin 490 620 130 Boonoonar Basins 440 570 130 Colignan Basins 120 150 30 Other salt pans 110 245 135 Within irrigated properties 0 110 110 Karadoc Swamp and Creeks 0 1,200 1,200 Lake Iraak 0 110 110 Bullock Swamp 0 350 350 Total 2,050 4,305 2,255

Sunraysia Draft Salinity Management Plan (Sunraysia CSWG 1991) This draft plan covered the irrigation districts of Robinvale, Red Cliffs, Mildura and Merbein. The districts at the time comprised 17,400 ha of irrigated horticulture. Combined, they were generating 28,000 ML of drainage water per year, of which 56% drained towards the (4% to floodplain, 52% to the river) and 44% finished up in 32 drainage basins. In total, 2,020 ha were occupied by drainage basins and many other areas were degraded by drainage transport and disposal. Also, the Murray River salinity was increasing each year by approximately 15 EC (electrical conductivity) units at Morgan (measured as microSiemens per centimetre) due to drainage outfalls (>60% of EC change) and irrigation induced groundwater seepage (<40% of EC change) in the Victorian Sunraysia region. Drainage water was often further contaminated with highly saline (50,000 EC) regional groundwater where the drainage system intersected areas of shallow watertables.

The Murray River floodplain has high environmental importance. An almost unbroken corridor of diverse aquatic and terrestrial riverine vegetation extends from Wentworth to Robinvale. Kings Billabong Wildlife Reserve is the most important conservation area in Sunraysia and was under threat from drainage disposal and rising groundwater levels. In 1991, the northern portion of the reserve was described as being in relatively good condition while the southern portion was extremely degraded.

Lakes Ranfurly and Hawthorn were natural floodplain lakes but levee banks constructed along the Murray River now restrict flooding of the lakes. They were originally freshwater lakes but are now saline, due to their use for disposal of drainage water and pumped groundwater. The lakes have maintained some environmental values (e.g. they support large and sometimes diverse bird populations) and have various recreational uses.

The Robinvale irrigation district had six major drainage system outfalls onto the Murray River floodplain. This has had an adverse effect on floodplain vegetation communities and wetlands at Gadsdens Bend, Knights Bend and Walshes Bend.

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The Mallee dunefields of Sunraysia contain productive soils that support dryland agriculture and irrigated horticulture. Historically, irrigation drainage disposal utilised convenient local and regional depressions creating artificial saline wetlands which support large populations of waterbirds. Major disposal sites include the Wargan Basins, Koorlong Basins and . State Forests located around the latter two sites are of regional conservation significance. Table 11 shows a list of specific environmental sites in the Victorian Sunraysia region, their conservation value, salinity status and salinity impacts with and without plan implementation.

Table 11. Salinity impacts on specified environmental sites in Sunraysia (after Sunraysia CSWG 1991) Site Conservation Salinity Consequences Impact of value status* of no plan preferred salinity (threat of doing control options nothing)# Kings Billabong Wildlife Reserve North High S4 Moderate No change South (Psyche Bend Basin 12) Moderate S4 Moderate Negative Sandalong Park Recreation Reserve High S4 Moderate -- Merbein Common Moderate S4 Moderate -- Southeast Moderate S2 Low -- Lake Ranfurly & Lake Hawthorn Low** S4 Moderate Positive Robinvale High S2 Low Positive Cardross Lakes Moderate S2 Low -- Koorlong Basins Low S2 Low -- Lamberts Swamp Low** S4 Low Positive Coars Swamp Low** S3 Low -- Wargan Basins Low** S3 Low Positive Legend:- * Salinity Status: S1 Sites with no evidence of salting. S2 Sites with low levels of salting – appearance of salt tolerant plants and evidence of salt stress in other plants. S3 Sites with moderate levels of salting – dominant salt tolerant plants, including some saline shrubs, and severe stress in other plants. S4 Sites with high levels of salting – dominant highly salt tolerant plants and shrubs; large areas of bare and salt encrusted ground. ** These sites may have a higher conservation value as they support large waterbird populations.

# Consequences of no plan:- High Significant deterioration of the present environment. Moderate Some deterioration of the present environment. Low Negligible deterioration of the present environment.

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Protecting Our River – Nyah to South Australian Border Draft Salinity Management Plan Background and Supplementary Reports (Nyah to the South Australian Border CSG 1992a and 1992b) Due to the dispersed nature of private diversion irrigation, this draft plan did not recognise boundaries as such. Instead, it covered all Victorian land and wetlands (in the Mallee region) downstream of Nyah that, (a) contribute or may contribute to river salinity, or (b) are being salinised or may be salinised by private diverters.

The draft plan built on the above plans for Nangiloc-Colignan and Sunraysia by aiming to reduce the environmental impact of existing water use within the region and by also proposing guidelines for trading water in the region.

The river salinity effect of extra irrigation development was categorised into two zones according to the amount of salt displaced to the river by each megalitre (ML) of applied water: low impact zone (up to 1 tonne of salt per ML) and high impact zone (>1 tonne of salt per ML). Two high impact zones were defined, namely (i) an area extending from the Robinvale irrigation district to about 20 km upstream, and (ii) a large area extending from the northern end of the Nangiloc-Colignan salinity plan area all the way downstream to the South Australian border.

In terms of risk to the Murray River from saline groundwater intrusion, the greatest risk river reaches are where the Murray River trench is directly connected to the highly saline regional aquifer, the Parilla Sand. In a downstream direction, these reaches are: • From Nyah, past Piangil to just south of the Wakool River mouth; • A small reach about 10 km upstream of Boundary Bend; • From Robinvale, past Wemen to halfway up the eastern side of Hattah-Kulkyne National Park; • From the northern part of Nangiloc-Colignan, past Mildura down to Yelta; and • From the lower Wallpolla Creek, past Lindsay Island to the South Australian border. The presence of irrigation and drainage disposal in these areas (e.g. Mildura) significantly increases the risk to the river.

Mallee Dryland Draft Salinity Management Plan (Mallee Dryland CSWG 1992) The plan simply defined the cause of salting in the Mallee as “extra water entering the groundwater system”. The plan proposed three ways of arresting this cause, namely:- • Pipelining the stock and domestic water supply. • Making more use of rainfall. • Encouraging better management of irrigation drainage water. The plan also recommended ways to treat the symptoms. However, the plan was very generalised and there was no specific definition of high risk areas or priority geographic areas for treatment.

Mallee Regional Catchment Strategy (Mallee CALP Board 1997) This strategy also did not define specific geographic areas for priority action. Instead, it defined nine (9) Regional Resource Management Units (RRMU) as a framework for management action. The RRMU were based on physical characteristics such as soil type, climate and topography. Table 12 shows their priority rankings in terms of severity of degradation processes.

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Table 12. Priority rankings of Mallee RRMU (after Mallee CALP Board 1997) RRMU Ranking Proportion (%) of total area Mallee Sands Public High 12 Northern Mallee Sands Dryland High 23 Southern Mallee Sands Dryland High 27 Irrigation High <1 Floodplain Public Medium 4 Floodplain Pastoral Medium 4 Lowan Sands Medium 24 Raak Public Medium 4 Raak Dryland Low <1

Mallee Catchment Technical Bulletin (SKM 2009) The main salinity risk areas based on shallow watertable areas identified from watertable mapping were:- • Tyrrell Basin (including Manangatang) • Raak Plains • Hattah Kulkyne National Park • Pink Lakes • Ouyen area • Murray Trench, particularly Lindsay Island and the irrigation area between Mildura and Colignan • Morkalla • Lake Agnes

Predicted “areas of concern” by 2050 (SKM 2009) were:- • Tyrrell Basin • The irrigation area between Red Cliffs and Colignan • Raak Plains • Hattah Kulkyne National Park • Morkalla • Pink Lakes • Lake Agnes • Hopetoun

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North Central Region

AVON-RICHARDSON CATCHMENT

Avon-Richardson Land & Water Management Plan – Draft (Avon-Richardson LWMG1992) Main areas of environmental interest affected by salinity or at future risk include (pp34-35 in A-RLWMG 1992): • ; • Avon (lower part) and Richardson Rivers; • York Plains; • Avon Plains Lakes; • Cope Cope Lakes •

From the salinity map (Fig. 9 in A-RLWMG 1992), main salt affected areas identified in 1992 were: • Lake Buloke and surrounding inter-lunette areas; • Donald township area (including lower Richardson River and small salinas west of Donald); • Cope Cope Lakes; • Avon Plains Lakes; • Rich Avon-Banyena (mainly Richardson River); • Marnoo (including Richardson River and Muddy Waterholes Creek); • Upper Faulkner Creek (near Kanya); • Paradise (upper Paradise Creek); and • Winjallok (upper Sandy Creek.

Identified high priorities (page 56 in A-RLWMG 1992):- 1. frontages of Avon and Richardson Rivers and their tributaries 2. the following high value wetlands: • Lake Buloke • Cope Cope Lakes • Avon Plains Lakes • Lake Batyo Catyo • Lake Jil Jil • Chirrup Swamp • York Plains • Waltons Lakes

3. the following specific communities: • Native Pine and Mallee woodlands, north-east of Donald • Buloke woodlands throughout catchment • Salt paperbark communities adjacent to Waltons Lakes • Redgum woodlands on western shore of Lake Buloke • Redgum forest and treeless herbfield at York Plains; and • Native grasslands scattered along roadsides and depressions.

AVOCA CATCHMENT

Avoca Catchment Salinity Management Plan – Draft (Avoca DCWG 1993) Main affected streams (pg 35): • (particularly from Natte Yallock to Berrimal West); • Fentons Creek; • Western, Middle and Carapooee Creeks; • Glenlogie Creek; • (Upper Mountain Creek)

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Most affected sub-catchments (>100 ha with **asterisks indicating >250 ha; pg 34): • Amphitheatre West; • **Moonambel; • **Natte Yallock (Plains); • Hines/Middle Creek; • **Cherry Tree Creek; • Black Ranges North; • Tarpaulin Creek; • **Western-Middle-Carapooee Creeks; • **Burkes Flat; • Logan; • Berrimal East; • **Bald Hill (Richmond Plains); and • **Gowar Park.

High Priority Areas (**asterisks indicate highest priority; from Appendix 1 in Avoca DCWG 1993):- • **Mt. Lonarch; • Amphitheatre; • **Amphitheatre West; • **Green Hill Creek; • Avoca South; • **Moonambel; • **Natte Yallock Plains; • **Hines/Middle Creek; • **Cherry Tree Creek; • **Black Ranges North; • Black Ranges South; • Smoky Creek; • Stuart Mill East; • Stuart Mill West; • **Tarpaulin Creek; • Western-Middle-Carapooee Creeks; • **Burkes Flat; • Logan; • Berrimal East; • Berrimal West; • **Bald Hill (Richmond Plains); • Mt. ; and • **Gowar Park

LODDON CATCHMENT

Loddon Catchment Salinity Management Plan – Draft (Loddon CWG 1992) High priority sub-catchments are (page xv, Exec Summary):- • Bet Bet Creek; • Middle/Joyces Creeks; • Mid ; • Loddon Plains; and • Bendigo / Myers Creeks (includes Kamarooka and Bendigo).

Medium priority sub-catchments are:- • Tullaroop Creek; and • Bullabul Creek

Low priority sub-catchments are:- • Upper Loddon River; and • Kingower / Korong Creeks.

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CAMPASPE CATCHMENT

Campaspe West – Planning for its future. Draft Salinity Management Plan (Campaspe West SRWG 1989) The Campaspe West sub-region comprised the part of the Campaspe Irrigation District (CID) west of the and a small part of the Rochester Irrigation Area (RIA) south of the Waranga Western Main Channel. At the time of this document, 3,400 ha of its 5,700 ha area was irrigated.

Despite the provision of surface drainage, high watertables developed quickly following commencement of irrigation in 1967-68 and salinity problems emerged in the late 1970s. At the time of the draft salinity management plan, watertables were within 2 metres of the surface across 60% of the sub-region with salinity effects visible across 13% and an additional 23% of area producing below its potential. Greatest impacts were in the northern part of the sub-region where watertables were shallowest.

Campaspe Catchment Salinity Management Plan – Draft (Campaspe CWG 1992) Most salt-affected Campaspe sub-catchments (Table 8, pg 23):- • Axe Creek; • Mt. Pleasant Creek (incl. Mt. Camel Range); • Forest Creek (Knowsley); • Wild Duck Creek; and • Lower (some of the recorded salinity, e.g. Elphinstone, is questionable or low severity). Note 1: two other listed, highly salt-affected sub-catchments are actually in other catchments, namely Bendigo Creek (Loddon) and Cornella Creek (Goulburn-Broken) Note 2: Axe Creek and Wild Duck Creek are high salt exporters, while the others in the list are rated as low salt exporters.

The Kerang Lakes Area Management Plan – Draft (KLAWG 1991) Essentially the whole of this area is a priority salinity management area, and accordingly a salinity province has been defined around the whole area (see Table 26, Section 5).

ASSALT: An asset based salinity priority setting process (Clifton and Heislers 2004) This report documented the development of ASSALT, a robust and transparent priority setting approach for assets and catchments exposed to dryland salinity within the North Central CMA. The approach was intended to ‘direct investment to the protection and/or restoration of assets of greater value and which remain in relatively good condition or can, in a cost-effective manner, be restored to good condition’.

ASSALT comprises two main phases. The first phase involves the derivation of a map of asset risk intensity. Locations of high asset risk intensity are those where there is relatively high confidence that more highly valued assets coincide with an existing or imminent salinity hazard. Asset value is based on a social, environmental and economic assessment of classes of asset that have been represented in GIS data sets. Salinity hazard is based on mapped land or stream salinity, high water tables, and relatively high groundwater and stream salinity.

The second phase of ASSALT is designed to assist decision making about where intervention should commence in order to protect or restore threatened assets. It first considers the merit in protecting or restoring asset condition and the potential for that to happen. It then considers the nature of salinity and other threatening processes operating, and facilitates an assessment of the types, location and likely success of interventions to protect or restore threatened and valued assets.

The Avoca catchment was used as a case study to test the application of the ASSALT priority setting process. Significant concentrations of asset risk occurred in the very upper reaches of the catchment, the Natte Yallock area, on land approximately between Stuarts Mill and Wedderburn, north-east of Wycheproof, and in the Avoca Marshes area. Scattered areas of asset risk are located across other parts of the catchment.

Salinity Provinces in Victorian Bioregions – 2011 29

Salinity Investment Framework 3 (SIF3) (Ridley et al 2006) SIF3 is an asset based framework developed by Anna Roberts (formerly Ridley) and David Pannell. In Ridley et al (2006) application of this framework relied on the application of a predictive watertable mapping method developed by Sinclair Knight Merz (SKM) to determine threats to assets (SKM, 2006). A detailed review of this regional scale watertable modelling method applied at the time (Gill et al 2008) showed it to be seriously flawed. A consequence of the identified flaws and reassessment of salinity risk is that a number of the priority threatened assets/areas identified in Ridley et al (2006) are not considered to be under serious threat of salinity. Examples from the above listed SIF3 priority areas in the NCCMA region include Elmore, , Merin Merin Swamp and Bridgewater.

Avon-Richardson priority areas based on SIF3 process: • Donald township (and lower Richardson River) • Avon Plains Lakes (including Lake Batyo Catyo) • Greys Bridge-Banyena (incl. Creswick Swamp and York Plains) Note: Lake Buloke, Cope Cope and the Richardson River (River Reaches 43 and 45) were considered but rejected on the basis of expense of treatment and tractability.

Avoca priority dryland areas based on SIF3 process: • Amphitheatre (including upper reach of Avoca River; Reach 8) • Natte Yallock • Gowar East springs (Avoca River, Reaches 5 and 6) • Avoca River Reach 5 indigenous site • Lower Avoca floodplain, Reaches 1 to 4 (incl. numerous high value wetlands and floodplain) Note: Redbank tourism, Carapooee, Warrenmang and Pental Hills were considered – the catchment wide program to develop options for salt and non-salt affected agricultural land help cover these areas.

Loddon priority dryland areas based on SIF3 process: • Tang Tang, incl. Tang Tang Swamp and other wetlands; Reach 42 • City of Greater Bendigo & surrounds (incl. Bendigo Urban Growth area & peri-urban areas) • Castlemaine Heritage area (Castlemaine, Chewton and Campbells Creek) • Merin Merin (including Merin Merin Swamp) • • Upper Loddon River, Reach 10 • Bridgewater (incl. Loddon River, Reach 7) Note: Laanecoorie, Bet Bet/Timor West, Mt Franklin, Birches and Creswick creeks, Mt Beckworth, Tullaroop and Tansfards Swamp were considered but not as highly valued as other areas. Bullabul was also covered in the original analysis. Boort Lakes were not included, as the high-value Woolshed Swamp should be covered by the Irrigation Plan.

Campaspe priority dryland areas based on SIF3 process: • Axe Creek • Tooborac-Heathcote • Wild Duck Creek • Lake Eppalock • Elmore, including Campaspe River Reach 4 Note: Knowsley East was analysed but not deemed high enough in asset value to be considered further. Mt Camel Range and Barnadown were also considered, and the recommendations on technology development would cover this.

North Central Dryland Region Management Plan – Draft (Delaney and Alexander 2007) Salinity priorities were based upon Ridley et al (2006) and so are the same as those listed above and subject to the same comments as in the Note above.

Salinity Provinces in Victorian Bioregions – 2011 30

Goulburn-Broken Region

Dryland management plan – Land and water salinity in the catchment of Goulburn- Broken Rivers, Victoria (Stage II report; McGowan International 1988) This plan covered the dryland portion of the Goulburn and catchments. It identified the location and extent of major dryland salinity problems by river catchment and sub-catchment as follows:

Goulburn River Catchment • Whiteheads Creek • Creightons Creek • Colbinabbin Range • Majors Creek • Sheep Pen Creek • Balmattum-Sheans Creek • Sunday Creek • Boho • Kialla East

Broken River Catchment • Molyullah-Tatong • Warrenbayne

Broken Creek Catchment • Dookie Hills

Particular focus at the time had been directed towards the following five (5) sub-catchments:- • Whiteheads Creek • Sheep Pen Creek • Warrenbayne-Boho • Molyullah-Tatong • Dookie

Thirteen (13) Land Management Units (LMU) were defined based on particular consistent geological or hydrogeological features, salinity characteristics and control options. They are listed in Table 13 together with general locations and priority for action at the time.

Table 13. Goulburn-Broken Dryland Land Management Units (after McGowan International 1988) Land Management Unit General Locations Priority For Action 1. Cambrian Volcanics and Sediments Dookie, Colbinabbin High 2. Violet Town Volcanics Warrenbayne, Balmattum, Boho, Sheans High Creek, Euroa 3. Silurian-Devonian Sediments (A) Caniambo, Earlston, Koonda High 4. Granites (A) Strathbogie, Longwood, Hughes Creek Low 5. Volcanics-Metamorphics-Sediments Molyullah, Tatong, Lurg High 6. Siluro-Devonian Sediments (B) Glenaroua, Puckapunyal, Rushworth High 7. Siluro-Devonian Sediments (C) Strath Creek, Yea, Alexandra, Whiteheads High Creek 8. Carboniferous Sediments Mansfield Low 9. Granites (B) Pyalong Low 10. Riverine Plain Sediments Miepoll, Kialla East, Yabba North, Low 11. Ordovician Sediments Goorambat, Devenish, Boweya Low 12. Granites (C) Wilby, Boweya Low 13. Basalt Broadford High

Salinity Provinces in Victorian Bioregions – 2011 31

Shepparton (Irrigation Region) Land and Water Salinity Management Plan – Draft (Goulburn-Broken Region SPPAC (1989) High watertables and salinisation problems were recorded in horticultural areas at Tongala and Bamawm in the 1930s and spread progressively thereafter. Mapping of regional watertables commenced in 1982. By 1989, high watertables (within 2m of the surface) were estimated to underlay about 188,000 ha (36%) of the Shepparton Irrigation Region, covering virtually all the more intensively irrigated and most productive land, as well as a significant number of high value conservation wetlands. High watertables were projected to extend to 274,000 ha (55%) of the Region by 2020. Areas which were obviously degraded were estimated in 1984 to total about 4,000 ha and additional areas were later identified. However, a much larger area was believed likely to be suffering significant production losses (up to 20%) mainly due to waterlogging, as salinity symptoms were not easily discernible. Studies carried out indicated that production losses could already have exceeded 20% in the Stanhope, Girgarre and Tongala areas.

The plan covered activities across the whole region, encompassing farm works, regional surface drainage, subsurface drainage, and environmental protection. Priority works involved joint management by government agencies and the community; examples of these included the Girgarrre Evaporation Basin Scheme, surface drainage construction, the Phase A and Phase B Subsurface Drainage (by groundwater pumping) Schemes, on-farm water efficiency programs and private groundwater pumping incentives programs.

Cheng et al 1999 High priority sub-catchments from west to east:- • Cornella (incl. Mt. Camel Range) • Majors Creek • Mollisons Creek • Kurkerac Creek • Dry Creek • Whiteheads Creek • Sheep Pen Creek plain and upland • Congupna (Ck) plain and upland (incl. Dookie) • Honeysuckle Creek upland (incl. Warrenbayne-Boho) • Creek • Four and (Lurg) • Holland Creek (Molyullah-Tatong • Broken upland (incl. upper Broken River and east side of Strathbogies)

Goulburn-Broken Dryland Salinity Management Plan – 1995-2001 Review (Goulburn- Broken CMA 2002).

Priority Assessment Summary The Goulburn-Broken was divided into several physiographic sub-regions and high priority ratings were based on high ratings for either or both in-catchment salinity risk and ex-catchment salinity risk (i.e. off- site impacts/risk).

BROKEN PLAIN HIGH PRIORITY AREAS Lower Broken R (Kialla East-Pine Lodge South) Congupna Ck Upland Muckatah Ck

BROKEN UPLANDS HIGH PRIORITY AREAS Four and Seven Creeks Holland Ck Broken River upland

Salinity Provinces in Victorian Bioregions – 2011 32

GOULBURN PLAIN HIGH PRIORITY AREAS Honeysuckle Ck Upland Sheep Pen Ck Plain Sheep Pen Ck Upland Lower Goulburn

SOUTH WEST GOULBURN HIGH PRIORITY AREAS Dry Ck Hughes Ck Kurkurac Ck Majors Ck Mollisons Ck Whiteheads Ck Sunday Ck

UPPER GOULBURN HIGH PRIORITY AREAS No high priority areas; mostly classed as low with some moderate.

WEST GOULBURN HIGH PRIORITY AREAS Cornella Ck

Salinity Provinces in Victorian Bioregions – 2011 33

North-East Region

Draft North East Salinity Strategy (NESWG 1997) The Draft North East Salinity Strategy (NESWG 1997) forms a component of the North East Regional Catchment Strategy (NERCLPB 1997) and acts as a framework for targeting priority on-ground salinity works. It identified over 2100 ha of salt-affected land (Table 14), along with trends (at the time) of steeply rising watertables in some Land Management Units (LMU). Salinity caused by rising watertables was identified as one of the factors contributing to water quality decline and the need for action on this was rated very highly in the Regional Catchment Strategy.

Seven of the thirteen defined LMU were identified as priority LMU, as follows: • Riverine Plain Lower Terrace • Riverine Plain Higher Terrace • Permian Tillite • Metamorphic Ridges • Sedimentary Rises • Western Sedimentary Hills and Mountains • Gneisses and Schists

The two Riverine Plain LMU were regarded as being of greatest concern due to: • the rapidly rising watertable (at that time); • the size and number of discharge sites; • the threat to floodplain and systems; and • the large area of high value agricultural land potentially under threat from salinity.

The salinity strategy identified priority areas for salinity control totalling an area of approximately 179,180 ha, mostly within the Ovens catchment. The priority salinity areas are shown with their calculated discharge areas and total areas in Table 15.

Table 14. Number of sites and total areas of salinity discharge points by Catchment Management Unit (after NERCLPB 1997) CMU No. of sites Total Area (ha) Alpine 0 - Dartmouth 0 - Lower Kiewa 22 355 Lower Mitta Mitta 4 5 Lower Ovens 64 1,048 Mid Kiewa 0 - Mid King 43 678 Mid Ovens 8 23 Omeo 0 - Upper Murray 1 6 Upper Ovens and King 0 - TOTAL 142 2,115 Source: Department of Sustainability and Environment, Soil salinity discharge area data layer, 2000.

Salinity Provinces in Victorian Bioregions – 2011 34

Table 15. Identified priority areas in the North East Region (after NESWG 1997) Priority areas Area of salinity discharge (ha) Total area (ha) Riverine Plain – Ovens / Upper Murray 569 43,920 / 15,000 Rutherglen 28 14,745 Springhurst / Byawatha 130 14,515 Indigo Valley 142 19,240 Wodonga / Baranduda 68 6,130 Everton / Tarrawingee 119 18,995 Carboor / Bobinawarrah 185 15,705 Greta 332 18,995 Murmungee 16 11,935 TOTAL 1589 179,180

East Gippsland Region

East Gippsland Regional Catchment Strategy – 2005-2010 (EG CMA 2005) The area of salt affected land in East Gippsland has not been fully mapped, although it is primarily associated with coastal locations. The Bengworden area within the Red Gum Plains management unit has the most extensive mapped area of salinity in the region (2400 ha). This is thought unlikely to increase rapidly in the short term but may have significant economic impacts over the long term. Poor irrigation practices could lead to localised watertable problems; therefore, environmentally sound irrigation practices should be encouraged in new and existing irrigation developments. The Bengworden area is included in the Lake Wellington Catchment Salinity Management Plan.

Current production losses from salinity are relatively small from a regional perspective. While some salinity investigation work has been undertaken in the Bengworden area, further work needs to be carried out in all the management units to assess salinity risk and potential risk reduction options.

In addition to the Bengworden area, the strategy concluded that further work was required to quantify the risks and impacts of salinity in the following areas: • Marlo ( Flats); • Corringle; • Brodribb; • Clifton Creek; • Flaggy Creek; and • Lakes Entrance areas.

Salinity Provinces in Victorian Bioregions – 2011 35

West Gippsland Region

Draft Management Plan (DCE 1990) CATCHMENT SALINITY This plan recognised that the salinity of wetlands fringing Lake Wellington (and to a lesser extent and Lake King) probably reflects a range of natural and anthropogenic processes. Some areas are considered to have been saline before European occupation (e.g. Lake Reeve), while others are showing the salinity effects of European modification. Apart from the opening of the Entrance in 1889 and its impacts on lake salinity (see below), human intervention has also contributed to the saline degradation of some wetlands around the lakes by way of changes to land cover and water movement that affect groundwater processes and stream flow.

Salinity problems caused by rising groundwater levels were identified in the Nambrok-Denison (Macalister) irrigation district in the 1950s. By1990, there was some control of groundwater levels through pumping, but evidence of continued groundwater rises occurred in other parts of the district. The pumped groundwater was drained to Lake Wellington, that together with increased salt loads in streams, led to increased lake salt loads. Salinity problems were also identified in over 10,000 ha of low lying land surrounding Lake Wellington and other small scattered areas throughout the Gippsland Lakes catchment.

LAKE SALINITY This plan also recognised that the intrusion of sea water (or ‘marine salinity’) through the Entrance, which was opened in 1889, continues to pose a serious threat to the quality of water in the Gippsland Lakes and that this acts to exacerbate other adverse impacts resulting from clearing of foreshores and urban development. There are a large number of direct and indirect effects of the marine intrusion. A few of these include: increases/fluctuations in salinity of lake waters, depletion of shoreline vegetation and resulting erosion, and loss of, or severe alteration to, breeding/wildlife habitats.

West Gippsland Salinity Management Plan 2005 (SKM 2005) The plan area includes the West Gippsland Catchment Management Authority region plus an additional area in the East Gippsland Catchment Management Authority region to cover the salinity in the Bengworden Salinity Management Area (also known as the “Red Gum Plains”). The East and West Gippsland CMAs decided to include the Bengworden Salinity Management region in this plan due to the similarity of salinity problems and solutions across the CMA boundary.

The groundwater flow systems (GFS) in and around the Macalister Irrigation District are reasonably well understood and the contained Clydebank, Nambrok, Heyfield, Maffra and Boisdale Salinity Management Areas have been used as a basis for the planning and implementation of salinity control measures for several years. Similarly, the GFS operating in the Bengworden region are also well understood from investigations conducted in the area (Sinclair Knight Merz, 2005).

Conversely, (in regard to salinity), there have been no investigations of the GFS operating in the rest of the region including South Gippsland, and the area to the south of the Gippsland Lakes. Therefore, the characteristics of the GFS causing dryland salinity are relatively unknown. This affects the ability to test and recommend effective management options in dryland areas. The plan identified a strong need to investigate salinity risk and the GFS contributing to salinity in the following priority dryland regions:- • Bengworden (in East Gippsland CMA region), • Foster, including south of Wonthaggi, the eastern flanks of the Bass Hills and the Powlett catchment (it is likely that much of the salinity is primary, • (incl. township), • Reeve (including Lake Wellington, refer also to Draft Gippsland Lakes Management Plan – DCE 1990) • Rosedale (incl. township), • Stratford, • Trafalgar, and possibly, • Walhalla.

Salinity Provinces in Victorian Bioregions – 2011 36

These areas cover the South Gippsland region and all areas south of the , the catchment of Lake Reeve, the forested area in the north of the region and the areas outside the Macalister Irrigation District.

The Walhalla area, or vast forested northern sector, of the West Gippsland CMA region was nominated in the WGCMA SMP as potentially being a salinity management priority but it is not clear why as it is nearly all forested and there is no known or mapped salinity incidence or threat of salinity to or from the area.

The change in resource condition from the implementation of the management actions was regarded as difficult to predict in the dryland areas relative to the irrigated Salinity Management Areas due to the lack of knowledge of the processes causing salinity and the effect of the management options on these processes.

The plan recommended a long term strategy development process to address dryland salinity in the region, whilst also providing shorter term “best bet” approaches that can be implemented while the longer term strategy is being formulated. According to the plan, the Salinity Management Areas with the greatest environmental, social and economic costs of dryland salinity, and therefore the greatest priority for investment in dryland salinity remediation, are: • Port Albert; • Bengworden; • Rosedale; • Foster; and • Reeve.

There are also gaps in the knowledge of the extent and effect of salinity on wetlands. The current state of knowledge on wetlands in the region is limited. There is a large disparity between the knowledge of different wetlands; detailed salt and water balance studies have been undertaken of wetlands such as Dowd Morass, Clydebank Morass and Lake Coleman, while there is almost no information available on wetlands such as Morley Swamp, Tucker Swamp and Backwater Morass.

Salinity Provinces in Victorian Bioregions – 2011 37

Port Phillip and Western Port Region

Port Phillip and Western Port Regional Catchment Strategy 2004-2009 (PP&WP CMA 2004)

The salinity section in chapter 6 (Land) identified significant economic, environmental and social impacts of salinity, particularly to infrastructure and agricultural production. Salinity caused estimated losses totalling $330,000 in regional agriculture and horticulture production in 1998. If the worst-case trends were to occur, and there was no intervention, the potential annual loss was predicted to potentially increase to more than $17 million by 2050. The following 10 ‘salinity hot spots’ were identified as areas where rising watertables were expected to become a serious issue, (clockwise from west to south-east):-. • Balliang • Rowsley • Rockbank • Upper Maribyrnong • Whittlesea • Packenham-Bunyip • Cranbourne • Mornington Peninsula • Bass • Phillip Island (Refer also to Phillip Island Draft Salinity Management Plan; PICSCG and DCNR 1992. This describes the island as having 1000 ha of dryland salinity, assumed to be mostly secondary, affecting 10% of the island).

Table 16 provides the framework used to assess the level of risk to the economic values of agriculture from salinity. The formula used was:-

Asset rating x Severity of threat x Sensitivity = Risk

Table 16 PP&WPCMA - Framework for risk to economic values of agriculture from salinity Economic value of Susceptibility of land areas to Susceptibility of enterprises to salinity agricultural production salinity 5 >$5,000/ha/yr 0.8 Salinity hot spots 0.6 Horticulture, viticulture 4 $2,000 to $5,000/ha/yr 0.1 Other lowland areas 0.4 Dairying, grazing, cropping and plantations 3 $1,000 to $2,000/ha/yr 2 $500 to $1,000/ha/yr 1 <$500/ha/yr

For example, high value agricultural industries, such as horticulture in the Mornington Peninsula salinity hot spot, have an asset rating of 5, a severity rating of 0.8 and a sensitivity rating of 0.6, giving a relatively high overall risk rating of 2.4.

Relatively high risks to agricultural production from salinity were particularly evident in the northern areas of the Western Port catchment and on the Mornington Peninsula. It was also noted that substantial urban growth is planned or occurring in some of these areas, and salinity (potentially) poses a serious risk to residential and urban infrastructure there. Other areas of medium-high risk were also indicated in parts of the Yarra catchment around Whittlesea, the upper Maribyrnong catchment and some areas of the Werribee catchment.

Numerous existing and potential risks were considered in planning to maintain the health and productivity of the region’s surface waters, rivers, streams and wetlands, but there was no specific mention or description of salinity as a risk/threat in the RCS.

Vegetation dieback was identified as occurring incrementally across the region, affecting important areas of native vegetation and consequently, biodiversity. Some of this was due to salinity. The identified salinity hot spots were a particular concern, as widespread salinisation was considered a possibility in the

Salinity Provinces in Victorian Bioregions – 2011 38 future. Other localised salinity impacts were also considered likely on the plains and lowland areas of the region. A framework used to assess the level of risk to the environmental values of native vegetation from salinity resulted in few high risk ratings. Medium and occasionally high risks to environmental values of native vegetation from salinity were particularly evident in parts of the Yarra catchment around Whittlesea, some areas of the Werribee catchment (particularly Rockbank), Pakenham-Bunyip, and the Mornington Peninsula.

Salinity Provinces in Victorian Bioregions – 2011 39

5. Results Soil salinity vs “flagships” & “biolinks” 3 Maps showing mapped salinity with “Flagships” and “Biolinks” (split into NW, SW and Eastern Victoria) are shown in Appendix A. These were developed as follows.

The Victorian GIS soil salinity spatial layer is the repository for mapped dryland salinity data across the State (Clark and Harvey 2007; Clark et al 2008). Using this layer, Tables 17 and 18, below, provide the currently recorded areas of soil salinity against severity class respectively for each “Flagship” and “Biolink” (as defined in the Land and Biodiversity White Paper 2010), current as of February 2011, from the DPI Corporate GIS Soil Salinity Layer.

There are some limitations in the soil salinity layer that need to be borne in mind when considering the information reported in Tables 17 and 18. Firstly, while the data coverage across the State is considered quite good, it is incomplete. The data layer comprises soil salinity data collected from private land in dryland areas only; it does not include any irrigation areas, and many public land areas (including Murray floodplain areas such as Lindsay-Wallpolla) are excluded (however, it is assumed that salinity occurrences in public land areas are predominantly due to natural processes). Data has not been obtained for all dryland areas; apart from public land, data does not exist for some coastal areas and low priority inland areas.

Secondly, being a data repository, the salinity layer contains data collected at different times over approximately a 30 year timeframe. Tables 17 and 18 report this data in total as contained in the layer in February 2011, and do not distinguish between old, new or updated/remapped data. As such, 30 year old data sits alongside recent data. Generally speaking, the older the data, the less reliable it is. Thirdly, some areas, most notably the Mallee, lack ground validation.

In consideration of the above limitations, the known soil salinity data coverage and professional knowledge of the data-poor areas, a medium confidence level has been assigned to area totals for all “Flagships,” except Mallee, Mega Murray and Far East Gippsland, for which low confidence levels have been assigned. For the “Biolinks”, a medium confidence level has been assigned to the North and Central Victoria, and Gippsland “Biolinks”, and a low confidence level to the Mallee “Biolink”.

Table 17 Mapped dryland salinity extent in “Flagships” (as at February 2011) “Flagship” Severity Area in Hectares (or Comment) Confidence Level Name Class A. Far East NA None recorded but some salinity known to occur in Low Gippsland Bengworden and Orbost-Marlo salinity provinces B. NA None recorded Medium C. Gippsland 1 1526.4 Lakes 2 1855.9 3 10179.7 4 71.8 8 1255.3 Total 14889.1 Medium

D. Wilson’s 1 280.7 Promontory 2 765.3 4 68.3 Total 1114.3 Medium

E. Central NA None recorded in area as defined in Land and Medium Highlands Biodiversity White Paper 2010

Salinity Provinces in Victorian Bioregions – 2011 40

Table 17 Mapped dryland salinity extent in “Flagships” (as at February 2011) continued

“Flagship” Severity Area in Hectares (or Comment) Confidence Level Name Class F. Goldfields 1 255.0 2 1400.2 3 298.8 4 28.9 8 5.4 9 7.5 Total 1995.8 Medium

G. Western 1 2303.7 Volcanic Plains 2 1807.2 3 26.6 4 17215.8 8 699.3 Total 22052.6 Medium

H. Otways 1 15.6 2 6.5 Total 22.1 Medium

I. South West 1 3035.6 2 938.4 3 2785.7 4 2993.0 8 847.3 Total 10600.0 Medium

J. Mega Murray 1 673.2 2 92.9 3 151.3 8 0.02 Total 917.4 (actual total is probably much greater; see Note 2) Low

K. Greater 1 155.3 Grampians 2 84.2 3 6.0 4 1.6 Total 247.1 Medium

L. Western Port 1 1074.9 2 1.9 4 714.1 8 22.9 Total 1813.8 Medium

M. Mallee 8 (and 40894.5 (significant proportion is primary salinity; see Low Total) Note 1) Severity Class Legend (after Clark et al 2008): 1 = slightly saline 2 = moderately saline 3 = highly saline 4 = extremely saline 8 = saline but severity not recorded 9 = non-saline area within a saline area

Note 1: Very high spatial salinity tallies are recorded for the Gippsland Lakes, Western Volcanic Plains, South West and Mallee Flagships, however, it is most probable that high proportions of these tallies (~50% or more) are due to some form of primary salinisation process.

Note 2: The Mega Murray “Flagship” tally is artificially low due in part to non-inclusion of irrigation area (or irrigation induced) salinity and, in part to no mapped salinity information for the Murray River floodplain (e.g. Lindsay-

Salinity Provinces in Victorian Bioregions – 2011 41

Wallawalla Salinity Province), however again, it is most probable that a high proportion of the salinity is due to primary salinisation processes.

In terms of total area affected by soil salinity (based on Table 17 and its notes), the following “Flagships” are the most impacted by soil salinity: • Gippsland Lakes • Western Volcanic Plains • South West • Mega Murray, and • Mallee

Salinity Provinces in Victorian Bioregions – 2011 42

Figure 1 Map showing the 140 salinity provinces against geology and faults. (for a higher resolution version of this map, please contact DPI in Bendigo)

Salinity Provinces in Victorian Bioregions – 2011 43

All these “Flagships” have a significant proportion of primary salinity.

Table 18 Mapped dryland salinity extent in “Biolinks” (as at February 2011) “Biolink” Severity Area in Hectares Confidence Level Name Class Mallee 1 554.0 2 581.2 3 976.6 4 828.2 8 4155.0 Total 7095.0 Low

North and 1 2273.4 Central 2 1827.2 Victoria 3 3550.1 4 3762.9 8 2591.3 Total 14004.9 Medium

Gippsland 1 1310.2 2 993.5 3 368.0 4 38.3 8 1450.0 Total 4160.0 Medium Severity Class Legend (after Clark et al 2008): 1 = slightly saline 2 = moderately saline 3 = highly saline 4 = extremely saline 8 = saline but severity not recorded 9 = non-saline area within a saline area

Note: While not to the same degree as in the Flagships, a significant proportion of mapped salinity in the Biolinks is likely to be due to some form of primary salinisation process.

In terms of total area affected by soil salinity (based on Table 18), the “Biolinks” that are most impacted by soil salinity are Mallee, and North and Central Victoria. Although the North and Central Victoria “Biolinks” record the largest salt affected area, it is noted that it covers a very large part of the State, therefore, the total mapped salinity area is only a small proportion of this.

Salinity Provinces in Victorian Bioregions – 2011 44

Salinity province identification Approximately 140 Salinity Provinces have been defined and mapped for the whole State of Victoria, including the irrigation areas (see figure 1). Starting with the Corangamite CMA region and continuing to other CMA regions in a clockwise direction, Tables 19 to 32 list the identified salinity provinces for the whole State, including irrigation areas, together with their dominant or critical groundwater flow systems (GFS) and comments about geological fault influence where known or suspected to occur.

The new statewide cover of Salinity Provinces is based on: (i) the review of priority salinity areas identified from Salinity Management Plans (SMPs), Regional Catchment Strategies (RCSs), and some associated documents, (ii) knowledge of salinity investigation history and (iii) professional appraisal of the current GIS cover of salinity extent and severity, together with the pattern and logic of salinity occurrence in the context of GFS, geology and structure.

Data layers used are:- • Victorian GIS soil salinity spatial layer; • Victorian 1:250,000 scale GFS data layer ; and • Victorian 1:250,000 scale geology and geological structural layers.

The most important GFS is listed first in the cases where multiple influential GFS are listed against a province. The influence of the nominated GFS is based on prior knowledge of the authors and large scale map interpretation, not on a thorough literature or data review. As such, they should be regarded as preliminary. In general, there is greater confidence for those GFS assigned to provinces north of the Great Divide. Included also in the tables are occasional qualitative comments as to the likely incidence of primary salinity; however no definitive distinction is made between primary or secondary salinity occurrences in the salinity provinces.

Salinity Provinces in Victorian Bioregions – 2011 45

Table 19 Corangamite Salinity Provinces Province Other localities, Main influential GFS #1 Structural influence name features and other comments Connewarre Ocean Grove, Barwon Local-intermediate marine sediments GFS; Lakes Heads, Leopold, Point local fractured basalt plains, and regional Lonsdale, Mt Duneed alluvial plains GFS Modewarre Breamlea, Moriac, Regional-intermediate marine and alluvial Freshwater Creek, GFS, and local-intermediate fractured Wurdiboluc, Lake basalt plains Modewarre Barrabool Hills Fyansford, Ceres, Local-intermediate layered sedimentary Structural influence Waurn Ponds, rocks [Otway Group], local-intermediate possibly important Gnarwarre, Mt.Moriac marine sediments, and fractured basalt plains Murdeduke Inverleigh, Shelford, Local-intermediate GFS in fractured basalt Campbelltown Fault Winchelsea, Wingeel, plains, scoria cones, stony rises and marine may define western Ombersley, Lake sediments, and local-intermediate GFS in limit of salinity and Murdeduke diverse unconsolidated Quaternary Rowsley Fault the sediments, overlying regional marine and eastern limit alluvial GFS Eurack Cressy, Beeac, Colac, Local-intermediate GFS in diverse Avoca Fault defines Warrion, Ondit, Lake unconsolidated Quaternary sediments, western limit/control of Colac, , fractured basalt plains, and minor scoria salt Cundare Pool cones/stony rises, overlying regional marine and alluvial GFS Barwon Downs Colac, Warncoort, Regional marine and alluvial GFS, local- Structural influence Gerangamete, Deans intermediate GFS in layered sedimentary possible Marsh, Barongarook, rocks [Otway Group] and local-intermediate Yeodene fractured basalt GFS #2 Bungador, Swan Marsh Multiple GFS in marine and alluvial Some structural sediments influence possible. Low priority Heytesbury #2 Timboon, Simpson, Port Multiple GFS in marine and alluvial Possible structural Campbell, sediments influence. Cooriemungle, Scotts Low priority – mostly Creek low severity salinity and waterlogging; not a target area in Corangamite SAP Lake Camperdown, Cloven Local-intermediate GFS in fractured basalt Structure broadly Corangamite Hills, Leslie Manor, plains, scoria cones and stony rises, local- important Pomborneit, intermediate marine sediments GFS, and regional marine and alluvial GFS Lismore Derinallum, Mingay, Local-intermediate fractured basalt plains, Structure broadly Berrybank, Foxhow regional marine and alluvial GFS, and local important GFS in scoria cones and stony rises Pittong Mannibadar Local-intermediate deeply weathered granite and colluvium Ballarat Hills Ballarat, Buninyong, Intermediate GFS in alluvial plains, incl. Haddon, Smythesdale, deep leads, local-intermediate deeply Napoleons weathered fractured Palaeozoic rocks, local to intermediate GFS in fractured basalt plains and minor local GFS in gravel cappings Illabarook Grenville, Little Hard Local-intermediate GFS in deeply Avoca Fault defines Hills, Cape Clear, weathered fractured Palaeozoic rocks and western limit of salt Rokewood local GFS in gravel cappings

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Table 19 Corangamite Salinity Provinces continued Province Other localities, Main influential GFS #1 Structural influence name features and other comments Upper Morrisons, Sheoaks, Local-intermediate GFS in deeply Muckleford Fault Moorabool Durdidwarrah, Mount weathered fractured Palaeozoic rocks (incl. possibly important Doran, Lal Lal, Gordon, granite), deep leads and fractured basalt Bungaree plains, and local GFS in gravel cappings Lara Anakie, Lovely Banks, Local-intermediate GFS in fractured basalt Low priority Avalon, The You Yangs plains, cones, marine sediments and deeply weathered granite, and local-intermediate GFS in unconsolidated Quaternary sediments

Note #1: Local-intermediate GFS in diverse unconsolidated Quaternary sediments occur in many of the above provinces. Note #2: While names may differ, essentially only two of the above provinces cover areas additional to those priority areas identified in Nicholson et al (2006), namely Heytesbury and Irrewillipe, both of which have been rated low priority.

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Table 20 Glenelg-Hopkins Salinity Provinces Province Other localities, Main influential GFS Structural influence name features and other comments Dorodong Wombat Ridge, Dismal Multiple GFS in Quaternary sand plains and Rated low priority but Swamp other unconsolidated sediments, underlain should be verified by regional GFS in marine sediments.

Merino Branxholme, Merino, Multiple GFS in deeply weathered Tablelands Casterton, Dergholm ferruginised tablelands and peripheral local- intermediate GFS in marine sediments and local-intermediate GFS in Quaternary sand plains West Dundas Balmoral, Harrow, Multiple GFS in deeply weathered Tablelands Chetwynd, ferruginised tablelands and marginally Konongwootong occurring local-intermediate marine sediments GFS East Dundas Coleraine, Cavendish, Deeply weathered ferruginised tablelands Tablelands Gatum, Melville Forest, GFS and marginally occurring local- Rocklands Reservoir intermediate marine sediments GFS Victoria Valley Mirranatwa, Bryan Local-intermediate GFS in weathered May include colluvial Swamp; southern granite, colluvium and alluvium slopes and fractured Grampians rock of adjacent Grampian Ranges Willaura Glenthompson, Yarram Local-intermediate GFS in fractured basalt, Park, Watgania, Lake local GFS in various unconsolidated Muirhead, Lake Quaternary sediments and local- Buninjon intermediate GFS in various fractured Palaeozoic rocks including Grampians Sandstone Ararat-Maroona Dobie, Denicull Creek, Local-intermediate GFS in fractured Rossbridge Palaeozoic metasediments and granites, local-intermediate GFS in fractured basalt, and local-intermediate GFS in various unconsolidated Quaternary sediments and Tertiary deep leads Beaufort Raglan, Waterloo, Local-intermediate GFS in fractured Trawalla Palaeozoic metasediments and granites and colluvium Burrumbeet Learmonth, Miners Local-intermediate GFS in fractured basalt, Low priority Rest, Snake Valley, deep leads and fractured Palaeozoic , Lake metasediments, and minor local GFS in Learmonth weathered granite Skipton Stoneleigh, Cross Local-intermediate GFS in fractured basalt Some structural Roads, Streatham, plains, scoria cones and stony rises, influence possible in the Mount Emu, Lake fractured Palaeozoic metasediments, deep west. Low priority Goldsmith, Lake leads and minor local GFS in weathered Wongan granite and Quaternary sediments Dundonnell North-east of Mortlake; Local-intermediate GFS in scoria cones and incl. Pura Pura, Barnie stony rises (late phase Newer Volcanics) Bolac and Darlington Terang Glenormiston North, Local-intermediate GFS in fractured basalt Elingamite North, and scoria, and local GFS in scoria cones Mumblin, Lake Bookar and stony rises; also local-intermediate GFS in marine sediments, regional alluvial GFS (?) and local GFS in diverse unconsolidated Quaternary sediments Mortlake- Hexham, Woolsthorpe, Multiple GFS in fractured basalt and scoria, Caramut Minhamite incl. local GFS in scoria cones and stony rises Woorndoo Chatsworth, Lake Bolac Multiple GFS in deeply weathered ferruginised tablelands, including local- intermediate GFS in weathered, fractured rock of various ages

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Table 20 Glenelg-Hopkins Salinity Provinces continued Province Other localities, Main influential GFS Structural influence name features and other comments Moffat North-west of Local-intermediate GFS in deeply Woorndoo and south of weathered Palaeozoic granite and Glenthompson metasediments Hamilton South Byaduk, Multiple GFS in fractured basalt and scoria, Penshurst, Moutajup, incl. local GFS in scoria cones and stony Mt. Napier, Lake rises Linlithgow Hawkesdale Gerrigerrup, Willatook Local-intermediate GFS in fractured basalt Low priority plains, scoria cones and stony rises, and minor local GFS in Quaternary sediments Warrnambool Port Fairy, Woodford Local-intermediate GFS in fractured basalt Majority of salinity likely plains, scoria cones and stony rises, and to be due to natural local GFS in Quaternary sediments coastal processes. Low priority Heywood Drumborg, Narrawong Local-intermediate GFS in fractured basalt Low priority plains, scoria cones and stony rises, intermediate-regional GFS in marine sediments, and local GFS in Quaternary sediments

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Table 21 Wimmera Salinity Provinces Province Other localities, Main influential GFS Structural influence name features and other comments Edenhope Langkoop, Apsley, Regional GFS in marine and alluvial Bringalbart, Goroke, sediments overlain by local to intermediate Wombelano, Lake aeolian, alluvial and paludal GFS Wallace Douglas Douglas, Miga Lake, Regional GFS in marine and alluvial Depression Clear Lake, Mitre, sediments overlain by local to intermediate Gymbowen, Mount aeolian, alluvial and paludal GFS Arapiles Wartook Laharum, Zumsteins; Local-intermediate GFS in weathered, Low priority northern Grampians fractured Palaeozoic rocks and colluvium and alluvium Telopea Downs Yannac, Miram, Regional GFS in marine and alluvial Possibly mostly primary Sandsmere, Dinyarrak, sediments overlain by local and salinity? Kaniva intermediate GFS in aeolian sediments Dimboola Lower Wimmera River, Regional GFS in marine and alluvial incl. Jeparit, Antwerp, sediments overlain by local-intermediate Lake Hindmarsh, Lake GFS in aeolian, alluvial and evaporite Albacutya sediments Peppers Plains East and SE of Lake Regional GFS in marine and alluvial Low priority Hindmarsh, incl. sediments overlain by local-intermediate Dalmalee, Crymelon, GFS in aeolian sediments Aubrey Watchem West East of Warracknabeal; Regional GFS in marine and alluvial Significant primary incl. Boolite, Carron and sediments overlain by local GFS in aeolian salinity? Warmur and alluvial sediments Warracknabeal- Minyip, Jung, Pimpinio, Regional GFS in marine and alluvial Some primary salinity Murtoa Byrneville, Wallup sediments overlain by local GFS in aeolian and structural control. sediments Low priority. Horsham Natimuk, Noradjuha, Regional GFS in marine and alluvial McKenzie Creek, Green sediments overlain by local GFS in aeolian Lake, St.Helens Plains sediments, and regional GFS in alluvial plains Moyston West and SW of Regional GFS in alluvial plains and local- Stawell, incl. Pomonal, intermediate GFS in weathered, fractured Bellellen, Lake Palaeozoic rocks Lonsdale Stawell Great Western, Local-intermediate GFS in weathered, Armstrong, Norval fractured Palaeozoic rocks and local- intermediate GFS in weathered granite and colluvium Navarre Frenchmans, Local-intermediate GFS in weathered, Landsborough, Greens fractured Palaeozoic rocks Creek Elmhurst Upper Wimmera, incl. Regional-intermediate GFS in alluvial plains Joel Joel, Crowlands, and local-intermediate GFS in fractured Mount Cole Creek Palaeozoic rocks

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Table 22 Mallee Salinity Provinces Province Other localities, Main influential GFS #1 Structural influence name features and other comments #2 Lindsay- Murray River floodplain Regional GFS in marine and alluvial Some structural control. Wallpolla islands west of Mildura, sediments overlain by local-intermediate Natural salinity incl. Lindsay Point, GFS in aeolian and salina processes exacerbated Neds Corner, Lindsay sediments/evaporites and Murray Trench by irrigation River, Wallpolla Ck. alluvials development Morkalla Karween, Tunart, Regional GFS in marine and alluvial Structural control northern Murray-Sunset sediments overlain by local GFS in aeolian evident and probably is Nat. Park and salina sediments/evaporites mainly primary salinity, but needs verification Mildura- Several irrigation Regional GFS in marine and alluvial Some structural control. Colignan districts and adjacent sediments overlain by local-intermediate Natural salinity dryland; incl. Merbein, GFS in aeolian sediments, salina processes exacerbated Red Cliffs, sediments/evaporites, and Murray Trench by irrigation Nangiloc, Carwarp, alluvials development Kings Billabong Hattah Lakes Includes some irrigation Regional GFS in marine and alluvial Some structural control. along Murray River; sediments overlain by local-intermediate Natural salinity Hattah Lakes NP GFS in aeolian sediments, salina processes potentially sediments/evaporites, and Murray Trench exacerbated by alluvials irrigation development Robinvale-Nyah Several irrigation areas, Regional GFS in marine and alluvial Some structural control. including Robinvale sediments overlain by local-intermediate Natural salinity district; Boundary Bend, GFS in aeolian sediments, salina processes exacerbated Hattah Lakes sediments/evaporites, and Murray Trench by irrigation alluvials development Raak Plains Hattah, Nowingi; most Regional GFS in marine and alluvial Structural control. of area is large salina sediments overlain by local-intermediate Primary salinity. complex GFS in aeolian and salina sediments/evaporites Cowangie- Koonda, Boinka; many Regional GFS in marine and alluvial Significant structural Underbool salinas in northern part, sediments overlain by local GFS in aeolian control and may be incl. Pink Lakes and salina sediments/evaporites mainly primary salinity but needs verification Ouyen Galah, Gypsum, Regional GFS in marine and alluvial Mainly primary salinity Mittyack, Kulwin sediments overlain by local GFS in aeolian with structural control and salina sediments/evaporites Tyrrell Basin Manangatang, Sea Regional GFS in marine and alluvial Mainly primary salinity Lake; Lakes Tyrrell, sediments overlain by local-intermediate with strong structural Wahpool and Timboram GFS in aeolian and salina control, e.g. Tyrrell sediments/evaporites Fault Lascelles Speed, Yarto, Gama, Regional GFS in marine and alluvial Much salinity strongly Woomelang, Curyo sediments overlain by local-intermediate correlated to faults. Low GFS in aeolian sediments priority but needs verification. Yaapeet Rainbow, Hopevale, Regional GFS in marine and alluvial Some structural control Kenmare sediments overlain by local-intermediate apparent. GFS in aeolian sediments Low priority but needs verification Note #1: There is no GFS cover for this region, so the 1:250,000 scale Geology cover was used instead. Note #2: There is a high proportion of primary salinity in this CMA region Note 3 : Two localities mentioned as salinity risk areas in SKM (2009) are not specifically included above. They are Lake Agnes and Hopetoun. Salinity (mostly or entirely primary?) is most likely significantly present in the Lake Agnes area but there is currently no recorded salinity in the Victorian GIS soil salinity spatial layer; a province for this area could be defined subject to further investigation. The Hopetoun area, while not specifically mentioned, is partly covered above by the Lascelles province.

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Table 23 North Central Salinity Provinces: Avon-Richardson catchment Province Other localities, Main influential GFS Structural influence name features and other comments Lake Buloke Donald, Corack, Regional GFS in alluvial and marine Probable structural Banyenong, lower reach sediments overlain by local-intermediate control/influence of Richardson River GFS in lunette sediments Cope Cope Swanwater West, Rich Regional GFS in alluvial and marine Probable structural Avon, Avon Plains, sediments overlain by local-intermediate control/influence Cope Cope Lakes and GFS in lunette sediments, and local- Lake Batyo Catyo intermediate GFS in deeply weathered fractured Palaeozoic rocks Marnoo Banyena, Grays Bridge, Regional-intermediate GFS in alluvial Callawadda, upper sediments and local-intermediate GFS in Richardson River, lower deeply weathered fractured Palaeozoic Avon River, York Plains rocks Swanwater-Gre Gooroc, Marnoo East, Local-intermediate GFS in alluvial and Low priority Gre Beazleys Bridge marine sediments and in deeply weathered fractured Palaeozoic rocks Paradise Upper Avon River Local-intermediate GFS in fractured and catchment, incl. deeply weathered fractured Palaeozoic Tottington, Winjallok rocks and minor alluvials

Table 24 North Central Salinity Provinces: Avoca catchment Province Other localities, Main influential GFS Structural influence name #1 features and other comments Amphitheatre Green Hill Creek, Mount Local-intermediate GFS in weathered, Low priority Lonarch fractured Palaeozoic rocks Natte Yallock Rathscar West, Intermediate GFS in alluvial sediments Likely structural Archdale Junction, influence Archdale Black Range Rathscar, Wiseman Hill Local intermediate GFS in weathered, Structural control – fractured Palaeozoic metasediments and Avoca Fault plus granite metamorphic aureole contact with granite. Low priority Pyrenees Moonambel, Stuart Mill, Local-intermediate GFS in fractured and Suspected structural Redbank, the Western, weathered, fractured Palaeozoic rocks and influence in places, e.g. Middle and Carrapooee local GFS in alluvial sediments Moonambel Creeks Tarpaulin Tarpaulin and Smoky Local-intermediate GFS in weathered Low priority Creeks, Mount Hawkins granite and colluvium and local GFS in gravel cappings Burkes Flat Between Logan and Local-intermediate GFS in deeply Possible structural Cochranes Creek weathered, fractured Palaeozoic rocks influence Pental Hills Logan, Gowar East, Local-intermediate GFS in fractured and Probable structural Nine Mile, Richmond weathered, fractured Palaeozoic rocks, control including Avoca Plains including granite Fault Glenloth #2 Part of Lower Avoca Regional GFS in alluvial sediments Perched, losing river on floodplain, incl. broad floodplain. Very Bunguluke and little salinity or risk at Ninyeunook present. Low priority Note #1: The Avoca Marshes, , Nyah West and Swan Hill are included in the Kerang Lakes salinity province (see under Loddon, below). Note #2: Clifton and Heislers (2004) identified an area of potentially high salinity risk to assets north-east of Wycheproof. The Glenloth salinity province, above, effectively captures this area but is rated low priority.

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Table 25 North Central Salinity Provinces: Loddon catchment Province Other localities, Main influential GFS Structural influence name features and other comments Lexton Upper Bet Bet Creek Local-intermediate GFS in weathered Possibly some catchment, including fractured Palaeozoic rocks (including structural control Burnbank Creek granite), and minor alluvials Upper Loddon Clunes, Carisbrook, Local to intermediate GFS in fractured Probable structural Volcanic Plains Moolort, Ascot, Newlyn, basalt plains and scoria cones influence from Tullaroop Reservoir, sedimentary bedrock, and Birch and Middle including faults, e.g. Creeks Campbelltown Fault Muckleford Maldon, Strangways, Local-intermediate GFS in weathered Low priority Muckleford Creek fractured Palaeozoic rocks and minor alluvials Ravenswood- Western half of the Local-intermediate GFS in weathered Possibly structurally Nuggetty Harcourt Granite granite and colluvium, and in weathered bound and influenced complex, incl. fractured Palaeozoic sediments Lockwood South and Cairn Curran Res. Woodstock Woodstock West, Bald Local-intermediate GFS in fractured basalt Probable structural Hill plains, deeply weathered Palaeozoic rocks influence from and shallow alluvials sedimentary bedrock, including faults, e.g. Campbelltown Fault. Low priority Timor West Wareek, Bet Bet, Intermediate GFS in alluvial sediments and Low priority Betley, Eddington local-intermediate GFS in deeply weathered fractured Palaeozoic rocks Bullabul Rheola, McIntyre, Local-intermediate GFS in deeply Arnold; Bullabul and weathered granite and colluvium Kangderaar Creeks Bendigo City and surrounds; incl. Local-intermediate GFS in weathered upper Bendigo Creek, fractured Palaeozoic rocks and minor Myers Flat, Epsom, alluvials Spring Gully Huntly Plains Huntly, Bagshot, Intermediate GFS in alluvial plains and Probable bedrock Goornong, Bendigo local-intermediate GFS in deeply weathered structural influence. Creek Palaeozoic sediments Low priority Kamarooka Kamarooka North, Intermediate GFS in deeply weathered Suspected structural Tandarra Pondage, Palaeozoic rocks and regional GFS in influence Tang Tang Swamp alluvial plains Loddon Plains Serpentine, Fernihurst, Regional GFS in alluvial plains overlain by Some structural Boort, Appin, Bears local-intermediate GFS in Quaternary influence Lagoon, Calivil, Pyramid alluvial, lake and lunette sediments Hill, Tragowel, Loddon floodplain and Pompapiel and Bullock Creeks Gunbower- Kerang, Cohuna, Regional GFS in alluvial and marine Benjeroop Koondrook, Murrabit, sediments overlain by local-intermediate Gunbower Island, lower GFS in Quaternary alluvial sediments and Loddon River, Kow minor lake and aeolian sediments Swamp, Barr and Pyramid Creeks Kerang Lakes Tyntynder, Swan Hill, Regional GFS in alluvial and marine Includes significant Tresco, Kerang, Avoca sediments overlain by local GFS in primary salinity with Marshes, Lake Quaternary aeolian, lake, evaporite and probable strong Tutchewop, , shallow alluvial sediments structural influences, Lake Charm, Kangaroo but with considerable Lake secondary modification. Note #1 : (i) The last four provinces above include irrigation areas. (ii) The eastern Loddon plains, including the Pine Grove-Lockington area, are included in the Campaspe-East Loddon Plains salinity province under Campaspe, below. (iii) The Kerang Lakes province also includes the lower end of the Avoca catchment.

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Table 26 North Central Salinity Provinces: Campaspe catchment Province Other localities, Main influential GFS Structural influence name features and other comments Wild Duck Baynton, Baynton East, Local-intermediate GFS in fractured and Structural influence Creek Glenhope weathered, fractured Palaeozoic rocks Redesdale- Mia Mia, Glenhope, Local-intermediate GFS in weathered, Low priority – mostly Barfold Sidonia, Metcalfe East, fractured Palaeozoic rocks, local- low severity salinity or Barfold Gorge intermediate GFS in fractured basalt, and waterlogging local GFS in alluvials Axe Creek Strathfieldsaye, Intermediate GFS in fractured and Structural influence, Axedale, Sedgwick, weathered, fractured Palaeozoic rocks and including Whitelaw Pilchers Bridge, Sutton local-intermediate GFS in alluvial sediments Fault Grange Knowsley Derrinal, Eppalock Local GFS in Permian glacial sediments Possibly some Reservoir (eastern arm and weathered fractured Palaeozoic rocks structural influence Mount Camel Redcastle, Toolleen, Local-intermediate GFS in fractured Strong structural Range Corop, Colbinabbin, Cambrian rocks (Cambrian axes), local- influence Lake Cooper; straddles intermediate GFS in deeply weathered Campaspe and west Palaeozoic rocks and minor alluvials and Goulburn catchments colluvials Campaspe-East Irrigation in eastern Regional GFS in alluvial plains Possibly some Loddon Plains part; includes Pine structural influence Grove, Lockington, along the Meadow Rochester, Bamawm, Valley Fault and Wharparilla East Campaspe Some irrigation; Regional GFS in alluvial plains Possibly some Plains includes Rochester, structural influence Strathallan, Simmie and Echuca Note 1 : Tooberac-Heathcote was identified in Ridley et al (2006) as a priority salinity area. A province could be defined for this area subject to further investigation but is likely to be a low priority due to low impacts. Note 2: Lower Coliban River area was identified in Campaspe CWG (1992) as a priority salinity area but field checking of mapped salinity areas in 2008 indicated only low incidence and low severity in the area.

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Table 27 Goulburn-Broken Salinity Provinces: Goulburn catchment Province Other localities, Main influential GFS Structural influence name features and other comments Broadford Puckapunyal, Local-intermediate GFS in fractured and Possibly some Glenaroua, Kilmore, weathered, fractured Palaeozoic rocks, structural influence Willowmavin, Wandong; local-intermediate GFS in fractured basalt Kurkurac, Dry, Sunday, plains and local-intermediate GFS in upland Sugarloaf and Mollisons alluvial valleys Creeks Majors Creek Costerfield, most of Local-intermediate GFS in fractured and Some structural Puckapunyal Army weathered, fractured Palaeozoic rocks and influence Reserve, Gardiners local-intermediate GFS in upland alluvial Creek valleys Whiteheads Seymour, Highlands Local-intermediate GFS in fractured and Some structural Creek weathered, fractured Palaeozoic rocks and influence including local-intermediate GFS in upland alluvial metamorphic aureole valleys Nagambie Tabilk, Wahring, Regional GFS in alluvial plains Possibly some Mitchellstown, Goulburn structural influence. Weir Low priority West Goulburn Irrigation area; incl. Regional GFS in alluvial plains, with Probably some Plains Colbinabbin, Tongala, possible local watertable perching in places structural control, e.g. Kyabram, Tatura, Corop Basin and Mt. Corop, Lake Cooper Scobie Shepparton- Mostly irrigation area, Regional GFS in alluvial plains, with Kialla incl. Zeerust, Lemnos, possible local watertable perching in Congupna, Pine Grove, places, including Kialla area Kialla East and lower Broken River Sheep Pen Caniambo, Earlston; Local-intermediate GFS in deeply Suspected structural Creek northern and eastern weathered, fractured Palaeozoic rocks and influence. extremities are in local-intermediate GFS in alluvial plains Low priority Broken catchment Longwood Locksley, Creighton, Local GFS in weathered Palaeozoic granite Rated low priority but Creightons Creek and sedimentary rocks, and local GFS in needs verification minor alluvium and colluvium Warrenbayne- Euroa, Violet Town, Local-intermediate GFS in acid volcanics Probable structural Boho Sheans Creek, Lima; and colluvial fans, and local-intermediate influence, as most eastern quarter is in GFS in weathered, fractured Palaeozoic salinity appears to be Broken catchment rocks around the interface of these two geologies/GFS Merton-Ancona Dry Creek, Woodfield Local-intermediate GFS in fractured Low priority Palaeozoic sediments and granite, and minor alluvials Mansfield Maindample, Goughs Local-intermediate GFS in fractured Low priority Bay, Boorolite, Ford Palaeozoic sediments (including Creek, ; intermediate GFS in layered, fractured northern part is in Carboniferous sediments in the east), and Broken catchment local-intermediate GFS in upland alluvials Note : for Mt. Camel Range, see under North Central and Campaspe.

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Table 28 Goulburn-Broken Salinity Provinces: Broken catchment Province Other localities, Main influential GFS Structural influence name features and other comments Murray Valley Mostly irrigation area, Regional GFS in alluvial plains incl. , , , Nathalia, Yarrawonga, Muckatah Depression and Broken Creek Boomahnoom- , eastern Local-intermediate GFS in deeply weathered Possibly some oonah Yarrawonga, Dowdle fractured Palaeozoic rocks, regional GFS in structural influence. Swamp and southern alluvial plains and minor local GFS in Low priority bank of Permian glacial sediments Invergordon mostly irrigation area, Regional GFS in alluvial plains, with Possible structural incl. Katandra West, possible local watertable perching in places influence. Rated high priority but needs to be verified Goorambat- St. James, Lake Local-intermediate GFS in weathered Low priority Devenish Rowan, Thoona, fractured Palaeozoic sediments and granite, Boweya and intermediate-regional GFS in alluvial sediments Dookie Cosgrove, Stewarton Local-intermediate GFS in fractured Possibly some Cambrian rocks (Cambrian axes) structural control. Low priority Molyullah- Benalla, Upper Lurg, local-intermediate GFS in fractured and complex geology with Tatong Samaria weathered, fractured Palaeozoic rocks, probable structural local-intermediate GFS in acid volcanics and control colluvial fans, local-intermediate GFS in alluvial sediments and local-intermediate GFS in fractured Cambrian rocks

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Table 29 North East Salinity Provinces Province Other localities, Main influential GFS Structural influence name features and other comments Greta Greta West, Greta Local-intermediate GFS in fractured Possibly some South, Hansonville Palaeozoic rocks (including Carboniferous structural influence. and Permian sediments) and colluvium, and Rated low priority but local-intermediate GFS in alluvial sediments should be verified. Bobinawarrah Carboor, Whorouly Local-intermediate GFS in fractured Structural influence South, Hurdle Creek Palaeozoic rocks and associated colluvials likely as most salinity along the eastern Ovens Graben fault line. Low priority. Everton Brookfield, Hodgsons Local-intermediate GFS in fractured Some structural Creek, Horseshoe Palaeozoic rocks, incl. granite, and in influence including Creek alluvials and colluvials granite contact. Low priority Murmungee Bowmans Forest, Local-intermediate GFS in deeply Structural influence. Burgoigee Creek weathered granite and colluvium Low priority surrounded by Palaeozoic metamorphic aureole Lower Ovens Moyhu, Oxley, Regional GFS in alluvial plains Possibly some Valley Wangaratta, structural influence. Boorhaman, Bundalong, Also geomorphic Dugays Bridge, lower influence – diagonal , lower Reedy orientation of Ovens Creek floodplain across the Ovens Graben Springhurst Byawatha, Boralma Local GFS in Permian glacial sediments, Probable structural local-intermediate GFS in fractured influence, as comprises Palaeozoic rocks and local GFS in complex geology and is weathered granite and colluvium adjacent to eastern Ovens Graben fault line Rutherglen Wahgunyah, Lilliput Local-intermediate GFS in weathered, Possible structural fractured Palaeozoic rocks, local GFS in control/influence – is Tertiary sand caps and regional GFS in bounded on eastern alluvial plains side by the eastern Ovens Graben fault line. Upper Black South of Chiltern, incl. Local to intermediate GFS in deeply Some structural control. Dog Creek Chiltern-Mt. Pilot Nat. weathered granite and colluvium and local- Low priority. Park intermediate GFS in alluvials Indigo Valley Barnawartha, Indigo Local-intermediate GFS in fractured Probable significant Upper Palaeozoic rocks and associated colluvials, structural control as local-intermediate GFS in fine and coarse- most salinity is in close grained metamorphic Palaeozoic rocks and proximity to a major associated colluvials (low grade fault system running metamorphism and fine textures along along the valley south-western side and high grade, (Kancoona Fault). schistose/gneissic textures along north- eastern side), and local-intermediate GFS in alluvials Talgarno North of Tallangatta and Local-intermediate GFS in fine and coarse- Possible significant adjacent to Lake Hume; grained metamorphic Palaeozoic rocks and structural control – incl. Mt. Talgarno and associated colluvials salinity appears to be Tallangatta Creek coincident with junction of the Kiewa and Tallangatta Creek Faults. Low priority. Corryong Cudgewa, Tintaldra, Local-intermediate GFS in various fractured Low priority Towong, Colac Palaeozoic rocks including metamorphic and granitic rocks, and local GFS in upland alluvials/colluvials Note : One priority area identified in NESWG (1997), Wodonga-Baranduda, is not covered by any provinces above. Although it would probably only attract a low priority rating, a province could be defined for this area subject to further investigation.

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Table 30 East Gippsland Salinity Provinces #1 Province Other localities, Main influential GFS #2 Structural influence name features and other comments Bengworden North-east of Lake Regional GFS in marine and alluvial Included in Lake Wellington, incl. Goon sediments overlain by local-intermediate Wellington Nure, Meerlieu, GFS in Quaternary aeolian, lagoonal and Management Plan and Cameron Point alluvial sediments West Gippsland SMP Orbost-Marlo #3 Newmerella, Intermediate GFS in alluvial sediments Possibly some Jarrahmond, Snowy overlying intermediate-regional GFS in structural influence as a River Flats irrigation marine and alluvial sediments? series of faults are area, Lake Corringle, mapped across the Lake Curlip area. Rated low priority but needs to be verified Note #1:. although it is probable that salinity is not a major issue in this region, especially compared to other regions, mapped salinity data and salinity knowledge is acutely deficient. Note #2: There is no GFS cover for this region, so the 1:250,000 scale Geology cover was used instead Note #3: Further work will be required to verify the risks and impacts of salinity in the Orbost-Marlo province, and additionally in Corringle (south of Newmerella), Brodribb (east of Orbost), Clifton Creek (north of ), Flaggy Creek (north-west of Bairnsdale) and Lakes Entrance areas. Very little is known about the salinity in any of these areas (EG CMA 2005).

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Table 31 West Gippsland Salinity Provinces #1 Province Other localities, Main influential GFS Structural influence name features and other comments Lake Wellington Sale, Clydebank, Loch Regional GFS in alluvial and marine See Note 2 under this #2 Sport, Lake Reeve, sediments overlain by local-intermediate table. Lake Coleman and GFS in Quaternary aeolian, lagoonal, and lower reaches of La alluvial sediments Trobe and Avon Rivers Macalister Mostly irrigation area, Regional GFS in alluvial and marine Structural/geologic incl. Heyfield, Nambrok, sediments overlain by local-intermediate boundary influence Denison, Boisdale, GFS in Quaternary alluvial sediments uncertain but possible Maffra and Stratford; (e.g. faulting or marine adjoins NW side of Lake boundary). Much Wellington salinity salinity could be related province to irrigation. Rosedale Flynn, La Trobe River, Regional GFS in alluvial and marine Large size and location Blind Joe Creek sediments (near marine boundary) overlain of salinity occurrence by local-intermediate GFS in Quaternary suggests marine alluvial sediments boundary and/or faulting influence. Rosedale township also affected. Moe Basin Yarragon, Trafalgar, Intermediate GFS in layered alluvial and No salinity mapped; Moe, Tanjil South, basalt sequence may be minor impacts Newborough; Moe and and could be largely La Trobe Rivers, Lake structurally controlled Narracan primary salinity. Low priority Woodside- Toora, Hiawatha, Port Regional GFS in alluvial and marine Area is structurally Yarram #3 Welshpool, Port Albert, sediments overlain by local-intermediate bound and some Jack Smith Lake GFS in Quaternary aeolian, lagoonal, salinity is possibly swamp and alluvial sediments structural controlled; (salinity may be due to a mixture of natural discharge from regional GFS, sea water intrusion and land use influence). Yanakie Sandy Point, Shallow Local GFS in swamp deposits overlying May be sea water Inlet, Waratah Bay various GFS in alluvials and fractured intrusion effects; Palaeozoic sediments and granite alternatively, could be natural spring discharge from adjacent hills north-west of Shallow Inlet and from granite hill south-east of Yanakie). Low priority. Inverloch Venus Bay, Tarwin Intermediate GFS in alluvial sediments, Salinity may be a Lower, Pound Creek, local-intermediate GFS in layered mixture of natural Wattle Bank sedimentary rocks (Strzelecki Group), and discharge from minor local GFS in Quaternary swamp intermediate alluvial deposits GFS under influence of Strzelecki Group structure, natural sea water intrusion, and land use influence. Hicksborough NW of Wonthaggi; Local-intermediate GFS in alluvial Cause and severity mouth sediments and local-intermediate GFS in uncertain – could be area, incl. Dalyston layered sedimentary rocks (Strzelecki structural control and/or Group) seawater intrusion; Rated low priority but needs to be verified.

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Note #1: mapped salinity data and salinity knowledge is deficient in parts of this region, especially dryland areas. Note #2: Salinity in the Lake Wellington Province could be largely a combination of primary salinity (structural influence; natural regional discharge location, particularly west side of lake), influx of saline water due to historical opening of sand barrier at Lakes Entrance, natural sea water intrusion (Lake Reeve); and possibly secondary effects from adjacent irrigation and dryland areas. It is possible that natural fresh groundwater discharge may have been significantly reduced due to deep pressure reduction caused by offshore oil and gas extraction and Boisdale Formation groundwater use (urban and irrigation). Note #3: The Foster area was described as a priority salinity area in the West Gippsland SMP (SKM 2005) but is not specifically covered by any of the above provinces, although it could be partially covered by the western side of the Woodside-Yarram province. There is currently no recorded salinity immediately around Foster in the Victorian GIS soil salinity spatial layer, making it difficult to define a province around it. However, a province could be defined subject to further investigation. Note 4 : The Walhalla area, a vast forested northern part of the West Gippsland CMA region, was nominated in SKM 2005 as potentially being a salinity management priority but it is not clear why, as it is nearly all forested and there is no known mapped salinity incidence or threat of salinity to or from the area.

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Table 32 Port Phillip and Western Port Salinity Provinces Province Other localities, Main influential GFS Structural influence name features and other comments Bass San Remo, Corinella, Intermediate GFS in alluvial and marine Probably significant Anderson, Woolamai; sediments and local-intermediate GFS in structural influence, lower layered sedimentary rocks (Strzelecki including Bass Fault Group) overlain by local-intermediate GFS in coastal plains and swamps French Island Fairhaven, Tankerton local-intermediate GFS in layered Possible structural sedimentary rocks (Strzelecki Group) and influence/control. local-intermediate GFS in fractured basalts Believed to be (Older Volcanics) overlain by local- undisturbed, therefore intermediate GFS in marine sediments primary salinity and (Baxter Formation) probably Low priority. Phillip Island Cowes, Summerland, local-intermediate GFS in fractured basalts Substantially salt- Cape Woolamai (Older Volcanics) with minor local GFS in affected, although a shallow alluvials major proportion could be natural causes. Mornington Upper part of Local-intermediate GFS in marine Probable structural Mornington Peninsula, sediments and local-intermediate GFS in control along Balcombe incl. Mt. Martha, Baxter, deeply weathered, fractured Palaeozoic and Tyabb Faults Tyabb, Hastings and rocks Balnarring Cranbourne Clyde, Carrum Downs, Local-intermediate GFS in marine Lyndhurst sediments, local-intermediate GFS in fractured basalts (Older Volcanics), and local-intermediate GFS in coastal plains and swamps Pakenham- Officer, Garfield, Nar Local GFS in weathered granite and Possible structural Bunyip Nar Goon colluvium, local-intermediate GFS in control and also fractured Palaeozoic meta-sedimentary possibility of some rocks, and local GFS in Quaternary alluvial Princes Freeway sediments influence (i.e. intercepting groundwater flow). Whittlesea- Wallan, Epping, Yan Local-intermediate GFS in fractured Craigieburn Yean, Kalkallo, Plenty Palaeozoic rocks, local-intermediate GFS in River, , Yan fractured basalts (Newer Volcanics), and Yean Reservoir local-intermediate GFS in upland alluvials Lancefield- Middle to upper Local-intermediate GFS in fractured Some structural Sunbury Maribyrnong catchment, Palaeozoic rocks, including Cambrian axis influence likely (e.g. Mt. incl. Romsey, rocks, and local-intermediate GFS in William Fault). Rated Clarkefield, Rockbank fractured basalts (Newer Volcanics) low priority but requires and Caroline Springs verification. Werribee Lower Werribee Plains, Intermediate-regional GFS in fractured Mainly primary salinity, incl. Laverton, Point basalt plains (Newer Volcanics), regional and was not included in Cook, Wyndham Vale, GFS in layered alluvial and marine the “hot spots” in Truganina sediments, and local-intermediate GFS in PP&WP CMA (2004). shallow alluvials (Werribee Delta). Low priority Rowsley Fiskville, Glenmore, Local-intermediate GFS in deeply incised Complex geology; Yaloak Vale, Parwan valleys of the Rowsley Complex (incl. some structural Creek Tertiary alluvials, Permian and Ordovician influence possible. rocks, and fractured basalts) Rated low priority but needs verification. Balliang Beremboke, Staughton Local-intermediate GFS in fractured Some structural control Vale, upper Little River, Palaeozoic rocks (metasediments and possible (e.g. Rowsley Balliang Creek, eastern granite), local-intermediate GFS in fractured Fault and the You You Yangs basalt plains (Newer Volcanics), regional Yangs Granite). Rated GFS in layered alluvial and marine low priority but needs sediments, and local-intermediate GFS in verification. shallow Quaternary alluvials

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Environmental asset areas The Land and Biodiversity White Paper (2010) defined for Victoria a series of environmental asset areas comprising priority biodiversity regions (“Flagships”) and strategic environmental regions linking these (“Biolinks”). These are listed in Table 33 and form the basis for priority setting and targeting protection of environmental assets. It is these defined regions to which this salinity risk assessment particularly applies. The above identified Salinity Provinces have been intersected with the defined environmental asset areas to derive a preliminary list of priority salinity provinces (Table 36) and to identify potential threatening salinity risks to key environmental assets.

Table 33 List of Environmental Asset Areas (“Flagships” and “Biolinks” – after Land and Biodiversity White Paper 2010) “Flagship” Asset Area Preliminary Land Health Program Salinity Investment Interest (as at 2010) A Far East Gippsland B Victorian Alps C Gippsland Lakes D Wilson’s Promontory E Central Highlands F Goldfields Localised salinity and soil degradation impacts threatening priority assets including goldfields vegetation. G Western Volcanic Plains Reducing rural land-based threats of dryland salinity to high value freshwater systems and native vegetation. H Otways I South West Long-term protection of high value wetlands and waterways threatened by dryland salinity J Mega Murray Management of salt loads from unsustainable dry rural land where it is a major threat. Reduction of impacts of soil degradation where this impacts on high value waterways and aquatic tributaries of the greater Murray system. Includes Murray River floodplain from S.A. border to Hume Reservoir; also Ovens, King and Kiewa Valleys, and lower . K Greater Grampians L Western Port M Mallee “Biolink” Asset Area Mallee North and Central Victoria Gippsland

Environmental asset areas vs salinity provinces The two tables below list the salinity provinces (see Tables 19 to 32) that intersect with the environmental asset areas. Table 34 lists salinity provinces that intersect with priority biodiversity regions (defined as “Flagships” in Land and Biodiversity White Paper 2010). Table 35 lists salinity provinces that intersect with strategic environmental linkage regions (defined as “Biolinks” in Land and Biodiversity White Paper 2010). The respective tables list the intersected salinity provinces against each “Flagship” and “Biolink”, highlighting the key intersections in terms of extent and severity (priority). Following and based on these tables, Table 36 summarises the preliminary, or “first cut”, priority salinity provinces grouped by CMA region.

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Table 34 Intersection of Salinity Provinces with priority biodiversity regions (“Flagships”) “Flagship” CMA Region Salinity Province Comments (highlighted ones = preliminary priority) A. Far East East Gippsland Orbost-Marlo Indicatively Low Priority (LP), but should be verified Gippsland B. Victorian None None Alps C. Gippsland East Gippsland Bengworden South edge in Flagship and SW third in Gippsland Lakes Biolink

West Lake Wellington About 40% flagship and about 55% biolink Gippsland D. Wilson’s West Woodside-Yarram Along southern edge, <10% of area; also about 40% Promontory Gippsland in biolink E. Central None None Highlands F. Goldfields Wimmera Navarre Eastern third

North Central Amphitheatre Northern tip only Pyrenees - Natte Yallock Northern tip only with all salinity outside flagship Tarpaulin Northern two-thirds; lower third in biolink; rated LP. Burkes Flat Eastern side, with most of salinity outside flagship Pental Hills Only small parts on SW edge and the NE Bullabul - Timor West LP Upper Loddon Volcanic Fringes only with most salinity outside flagship Plains

Woodstock Small area in the west; LP Loddon Plains Small area on SW edge Kamarooka Small area along SE margin; remainder in biolink Huntly Plains LP Bendigo - Axe Creek - Ravenswood-Nuggetty Eastern two-thirds; remainder in biolink Muckleford LP Redesdale-Barfold Western third; LP Wild Duck Creek Northern third only; most salinity outside flagship Knowsley - Mount Camel Range Southern tip only; both sides of NCCMA and GBCMA boundaries Goulburn- Majors Creek - Broken Nagambie Small area on western side; LP

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Table 34 Intersection of Salinity Provinces with priority biodiversity regions (“Flagships”) continued “Flagship” CMA Region Salinity Province Comments (highlighted ones = preliminary priority) G. Western Port Phillip and Werribee Mainly primary salinity; LP Volcanic Western Port Plains Balliang SE third but rated LP. However, verification required.

Lancefield-Sunbury Small area in south end; rated LP but needs verification

Corangamite Lara LP Barrabool Hills Along north to NW margin Murdeduke - Barwon Downs Northern 10% only Irrewillipe Small area on north edge; LP Eurack - Lake Corangamite - Lismore - Pittong Approx. half of area; remainder in biolink Illabarook Approx. one-third of area; remainder in biolink Upper Moorabool Approx. southern quarter; remainder in biolink Glenelg- Terang Approx. two-thirds of province; rated LP but should Hopkins be verified

Mortlake-Caramut Approx 5% of province at east end Dundonnell - Woorndoo - Moffat - Willaura About 85% of area; remainder is biolink and Greater Grampians Flagship

Ararat-Maroona About half of area; remainder is biolink Skipton LP Beaufort Small area on SW edge; remainder is biolink H. Otways None None I. South West Glenelg- Heywood - Hopkins Dorodong Rated LP but should be verified Merino Tablelands More than half of western side West Dundas Western half, plus about 20% in biolink Tablelands Wimmera Edenhope - Douglas Depression - Dimboola Approx. southern 10%; remainder mainly biolink Warracknabeal-Murtoa Very small area in the west; LP

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Table 34 Intersection of Salinity Provinces with priority biodiversity regions (“Flagships”) continued “Flagship” CMA Region Salinity Province Comments (highlighted ones = preliminary priority) J. Mega Mallee Morkalla Plus biolink and small area of Mallee Flagship; Murray interpreted to be mostly primary salinity and (also includes therefore rated LP, but this needs verification. the Ovens, Lindsay-Wallawalla King and - Kiewa Valleys Mildura-Colignan Minor proportion of area but significant salinity risk and the lower Goulburn Hattah Lakes Also including biolink and Mallee Flagship River) Robinvale-Nyah About half of area North Central Kerang Lakes Most of province Gunbower-Benjeroop Most of province, plus some biolink Loddon Plains Northern tip only Campaspe-East Loddon Approx. northern 20%; most salinity outside flagship Plains

East Campaspe Plains Approx. northern 20%; most salinity outside flagship Goulburn- West Goulburn Plains Approx. northern 5% only Broken Shepparton-Kialla Small area in NW

Murray Valley Along SW and northern margins; salinity outside flagship

Boomahnoomoonah Northern margin only – adjacent to Lake Mulwala; LP North East Lower Ovens Valley About 70% of area; remainder is biolink Greta About 60% of area with remainder in biolink; rated LP but should be verified

Bobinawarrah LP Murmungee About half of area with remainder in biolink; LP Everton Most of area with remainder in biolink; LP Rutherglen About 40% of area on NW or Murray River side plus small area of biolink

Indigo Valley Approx. 10% of area in NE corner; most salinity outside flagship K. Greater Glenelg- East Dundas Tablelands About 10% of area, along NE margin; salinity is Grampians Hopkins outside this

Victoria Valley -

Willaura Western fringe, but mostly in Volcanic Plains Flagship Wimmera Wartook Eastern half, but most salt outside Flagship; LP

Moyston Western third; remainder is in biolink where all salinity is mapped

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Table 34 Intersection of Salinity Provinces with priority biodiversity regions (“Flagships”) continued “Flagship” CMA Region Salinity Province Comments (highlighted ones = preliminary priority) L. Western Port Phillip and Phillip Island Significant proportion could be primary causes Port Western Port French Island LP; primary salinity

Bass Western and northern margins, plus about 15% in biolink

Mornington Eastern margin only M. Mallee Mallee Morkalla Small proportion in south but is mostly in Mega Murray Flagship (see comment under Mega Murray)

Raak Plains Severe but mostly primary salinity, therefore LP

Hattah Lakes Approx. 15% in NW; remainder mostly Mega Murray Flagship and some biolink

Cowangie-Underbool Mainly in north part – Pink Lakes area; interpreted to be mostly primary salinity, therefore rated LP but needs verification

Yaapeet <5% area in north; LP

Wimmera Dimboola Small area in north; also some biolink and South West Flagship LP = Low Priority Salinity Province Note: the highlighted Salinity Provinces above are regarded as preliminary or “first cut” high priority provinces based on complete or major intersection (30% or more) with one or more “Flagships” (plus “Biolinks”) and on the extent and severity of salinity within the intersected “Flagship”, unless known to be mainly primary (natural) salinity.

IMPORTANT NOTE: three salinity provinces have been identified (and there may well be others) that are not listed above or in the table below (i.e. do not intersect any “Flagships” or “Biolinks”) but are considered to have significant environmental assets potentially at threat. They are:- • Connewarre Lakes (Corangamite CMA region) • Lake Buloke (North Central CMA region); and • Cope Cope (North Central CMA region)

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Table 35 Intersection of Salinity Provinces with strategic linkage regions (“Biolinks”) “Biolink” CMA Region Salinity Province Comments (highlighted ones = preliminary priority) Mallee Wimmera Telopea Downs About half of area but not worst affected part

Dimboola Includes Lake Hindmarsh; also has some flagship in the south Mallee Morkalla In eastern part; is mostly in Mega Murray Flagship and has small Mallee Flagship area; interpreted to be mostly primary salinity and therefore rated LP, but this needs verification.

Hattah Lakes Approx. southern 15%; remainder mostly Mega Murray Flagship with some Mallee Flagship

Robinvale-Nyah Small area at western end

Tyrrell Basin In the NW, <10% of province

Ouyen About 75% of area; could be high proportion of primary salinity; needs verification

Lascelles In the NW, about quarter of area; rated LP but needs verification

Yaapeet In the north, about quarter of area; rated LP but needs verification North and Corangamite Lara Small area in the north with most of remainder in Central flagship; LP Victoria Upper Moorabool About 75% of area, with remainder in flagship

Ballarat Hills

Illabarook About two-thirds of area with remainder in flagship

Pittong Approx. half of area; remainder in flagship

Glenelg- Burrumbeet LP Hopkins Beaufort >90% is biolink with remainder in flagship

Skipton About 15% in biolink; remainder in flagship; LP

Ararat-Maroona About half of area; remainder is flagship

Willaura About 10% of area; remainder is flagship

East Dundas Tablelands About one-third of area but almost all mapped salinity is outside this

West Dundas About 20% in biolink; western half in flagship Tablelands

Wimmera Horsham Small area in the south

Moyston Eastern two-thirds; remainder in flagship

Stawell

Elmhurst

North Central Amphitheatre Plus small area of flagship in the north; rated LP

Lexton -

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Pyrenees Small area in east, but remainder is Goldfields Flagship

Tarpaulin Lower third, with northern two-thirds in flagship; rated LP

Natte Yallock About 85% of area, with remainder in flagship

Black Range LP

Timor West Small area in west with most of remainder in flagship; LP

Upper Loddon Volcanic Small area in south Plains

Ravenswood-Nuggetty Western third with remainder in flagship

Woodstock Plus small flagship area in west; LP

Loddon Plains Plus small areas of flagship around edges

Kamarooka Plus some flagship in the south

Campaspe-East Loddon About a third of area in the SW, plus some flagship Plains in the north but most salinity is outside; some verification required

Gunbower-Benjeroop In the SW, about 15% of area; remainder is flagship

Goulburn- Majors Creek Small area in south but most of remainder in flagship Broken Broadford About half of area

Whiteheads Creek -

Nagambie Plus small area of flagship in west; LP

Longwood LP

Merton-Ancona LP

Mansfield About 20% of area, in the west; LP

Warrenbayne-Boho -

Molyullah-Tatong About one quarter of area, in the south; most salinity outside biolink

Sheep Pen Creek Southern two-thirds; LP

Goorambat-Devenish About 15% of area, in the east; LP

North East Greta About 40% biolink and about 60% flagship; rated LP but should be verified

Murmungee About half of area with remainder in flagship; LP

Everton About 25% of area with remainder in flagship; LP

Lower Ovens Valley About 30% but remainder is flagship

Springhurst -

Rutherglen Small area in south but about 40% in flagship

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Upper Black Dog Creek LP

Indigo Valley Plus a bit of flagship in the north

Talgarno LP

Corryong LP

Port Phillip and Whittlesea-Craigieburn In the north, about 10% of area, and all or most of Western Port salinity is outside biolink

Lancefield-Sunbury Very small areas along western boundary

Rowsley Rated LP but needs verification

Balliang Plus southern third in flagship; rated LP but needs verification Gippsland East Gippsland Bengworden SW third in biolink; south edge in flagship

West Gippsland Lake Wellington About 55% biolink and about 40% flagship

Macalister NE fifth only

Rosedale In the SE, about 15% of area

Woodside-Yarram Northern third and SE and western edges; also, southern edge intersects flagship

Yanakie About half of area but is LP

Inverloch Southern half

Hicksborough Most of area but is LP

Port Phillip and Bass About 15% of area; plus flagship around western Western Port and northern margins LP = Low Priority

Note: The above are regarded as preliminary or “first cut” high priority provinces based on complete or major intersection (30% or more) with a “Biolink” (plus “Flagship”) and on the extent and severity of salinity within the intersected “Biolink”, unless known or interpreted to be mainly primary (natural) salinity. A further qualification to this is that intersection with “Biolinks” may not carry the same weight as intersection with “Flagships”, unless those provinces highlighted above also intersect “Flagships”.

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Table 36 Preliminary list of priority Salinity Provinces (based on Tables 34 and 35) CMA Region Priority Salinity Province Dominant Intersected Dominant Intersected (Preliminary) “Flagship” “Biolink” Corangamite Murdeduke Western Volcanic Plains none Eurack Western Volcanic Plains none Lake Corangamite Western Volcanic Plains none Lismore Western Volcanic Plains none Pittong Western Volcanic Plains North and Central Victoria Illabarook Western Volcanic Plains North and Central Victoria Upper Moorabool Western Volcanic Plains North and Central Victoria Ballarat Hills none North and Central Victoria

Glenelg- Dundonnell Western Volcanic Plains none Hopkins Woorndoo Western Volcanic Plains none Moffat Western Volcanic Plains none Willaura Western Volcanic Plains North and Central Victoria Ararat-Maroona Western Volcanic Plains North and Central Victoria Victoria Valley Greater Grampians none Heywood South West none Merino Tablelands South West none West Dundas Tablelands South West North and Central Victoria

Wimmera Navarre Goldfields none Edenhope South West none Douglas Depression South West negligible Dimboola South West Mallee Moyston Greater Grampians North and Central Victoria Stawell none North and Central Victoria Elmhurst none North and Central Victoria

Mallee Lindsay-Wallawalla Mega Murray none Mildura-Colignan Mega Murray none Hattah Lakes Mega Murray Mallee Robinvale-Nyah Mega Murray Mallee Ouyen none Mallee

North Central Pyrenees Goldfields North and Central Victoria Bullabul Goldfields none Bendigo Goldfields none Axe Creek Goldfields none Ravenswood-Nuggetty Goldfields North and Central Victoria Knowsley Goldfields none Kerang Lakes Mega Murray none Gunbower-Benjeroop Mega Murray North and Central Victoria Lexton none North and Central Victoria Natte Yallock Goldfields (minor) North and Central Victoria Loddon Plains Goldfields (minor) North and Central Victoria Kamarooka Goldfields (minor) North and Central Victoria

Goulburn- Majors Creek Goldfields North and Central Victoria Broken Broadford none North and Central Victoria Whiteheads Creek none North and Central Victoria Warrenbayne-Boho none North and Central Victoria

North East Lower Ovens Valley Mega Murray North and Central Victoria Rutherglen Mega Murray North and Central Victoria Springhurst none North and Central Victoria Indigo Valley Mega Murray (minor) North and Central Victoria

East Gippsland Bengworden Gippsland Lakes (minor) Gippsland

West Gippsland Lake Wellington Gippsland Lakes Gippsland Woodside-Yarram Wilson’s Promontory (minor) Gippsland Port Phillip and Phillip Island Western Port none Western Port NOTE: The 18 bolded salinity provinces intersect both ‘Flagships’ and ‘Biolinks’

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Based on this table, the most intersected, or highest preliminary priority “Flagship” areas, are:-

• Western Volcanic Plains • South West • Mega Murray • Goldfields

Note that three provinces containing a large area of mapped soil salinity recorded in the Mallee and Gippsland Lakes “Flagships” aren’t among the above four priority ‘Flagship’ areas. In the Mallee “Flagship” area, the Raak Plains and Cowangie-Underbool salinity provinces are severely salt affected, but they are considered to have most or all of their intersected portions affected by primary salinity. Likewise the most significant mapped salinity intersection within the Gippsland Lakes “Flagship” area is the Lake Wellington salinity province, where the vast majority of the significant total of mapped soil salinity occurs (see Table 18). While these are important areas and cannot be ignored, most of the salinity is interpreted to be of primary origin (natural groundwater discharge and/or tidal zone intrusion linked), therefore reducing the priority relative to the above four listed “Flagships”.

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Groundwater trends for salinity provinces The following table lists observation bore data from each priority salinity province for each CMA region. Note that for the Goulburn Broken and NE regions, additional detail for slope class bores (lower, mid and upper slope) and a range of bores is available from the more detailed assessments undertaken by Cheng et al (2011 – in draft) for the Murray Darling Basin salt loads modelling review.

The trend data is from typical observation bores selected after plotting all key hydrographs in each province and taking into account landscape position, length of record and responsiveness. The trend rates are calculated over the period indicated as a per annum rate of fall (-ve) or rise (+ve). The key observations are that the drought period resulted in universal declines in level, and the last two years have seen almost all bores rise again, in many cases by a significantly greater rate than the previous rate of fall. Of the bores that have a strong to very strong response to the recent wet conditions in upland areas, the water levels have returned to a similar level as 2001.

Table 37 Listing of typical groundwater trends (or range) for each priority salinity province. CMA Region Priority Salinity Trend 2001 – 09 Trend 2009 – 11 Comments Province (dry years (wet year (Preliminary) response - per response – per annum) annum) Corangamite Murdeduke -0.14 to -0.27 +0.02 to +0.56, 5 bores Eurack -0.05 to -0.26 +0.27 to +1.43 8 bores Lake Corangamite -0.15 to -0.34 +0.58 to +1.47 6 bores Lismore -0.04 to -0.19 -0.04 to +1.21 8 bores Pittong +0.03 to -0.16 No data 4 bores Illabarook -0.29 to -0.39 -0.18 to +1.61 3 bores Upper Moorabool -0.07 to -0.59 +0.43 to +3.33 6 bores Ballarat Hills -0.18 to -1.36 +0.94 to +3.08 5 bores Glenelg- Dundonnell -0.09 to -0.26 +0.03 to +0.91 7 bores Hopkins Woorndoo -0.06 to -0.28 +0.02 to +0.68 8 bores Moffat -0.08 to -0.49 +0.06 to +0.09 2 bores Willaura -0.02 to -0.23 +0.11 to +0.89 3 bores Ararat-Maroona -0.12 to -0.23 0 to +1.16 9 bores Victoria Valley -0.01 to -0.4 -0.41 to +1.3 5 bores Heywood -0.13 to -0.17 +0.23 to +0.49 10 bores Merino Tablelands -0.15 to -0.58 +0.13 to +0.55 3 bores West Dundas -0.12 to -0.23 No data 4 bores Wimmera Navarre -0.551 +1.6 Bore 163 Edenhope -1.65 +2.17 Bore 67829 Douglas Depression -0.021 -0.03 Bore 66595 Dimboola -0.082 +1.14 Bore 110091 Moyston -0.083 +0.41 Bore 11693 Stawell -0.127 +4.73 Bore 67750 Elmhurst -0.48 +1.85 Bore 5396 Mallee Lindsay-Wallawalla -0.33 +0.14 Bore 7933 Mildura-Colignan -0.073 +0.8 Bore 69464 Hattah Lakes -0.074 No data (2007) Bore 26276 Robinvale-Nyah -0.348 +0.87 Bore 1264 Ouyen -0.04 No data (2004) Bore 116644 North Central Pyrenees -0.555 +1.25 Bore 6416 Bullabul -0.38 No data (2005) Bore 6331 Bendigo -0.163 +0.996 Bore 60013 Axe Creek -0.172 -0.126 Bore 13 Ravenswood-Nuggetty -0.030 No data (2005) Bore 6536 Knowsley -0.234 +2.74 Bore 6942 Kerang Lakes -0.22 +0.78 Bore 6485 Gunbower-Benjeroop -0.355 +1.13 Bore 66515 Lexton -0.282 +2.62 Bore 254 Natte Yallock -0.172 +0.86 Bore 103 Loddon Plains -0.528 +3.07 Bore 279 Kamarooka -0.007 -0.09 Bore 76

Salinity Provinces in Victorian Bioregions – 2011 72

Table 37 Listing of typical groundwater trends (or range) for each priority salinity province (cont.)

CMA Region Priority Salinity Trend 2001 – 09 Trend 2009 – 11 Comments Province (dry years (wet year (Preliminary) response - per response – per annum) annum) Goulburn- Majors Creek LS: -0.25 to -0.42m LS: +1.11 to +2.02m LS: DPI 9068, 9056 Broken MS: -0.21 to -0.32m MS: +1.45m MS:DPI 9052, 9060 US: -0.26 to -0.59m US: +0.22 to 1.05m US: DPI 65, 9058 Broadford LS: -0.16 to -0.22m LS: No data (2009) LS: DPI 9136, 9138 MS: -0.37m MS: No data (2009) MS: DPI247 Whiteheads Creek LS: -0.28 to -0.5m LS: No data (2009) LS: DPI9016, 9018 MS: -0.25 to -0.34 m MS: No data (2009) MS: DPI9001, 9010 US: -0.5m US: No data (2009) US: DPI161 Warrenbayne-Boho #1 LS: -0.24 to -0.34m LS: +0.6 to 0.82m LS: DPI8454, 8455 MS: -0.29m MS: +1.01m MS: DPI8420 US:-0.78m US: +2.89m US: Molyulla-Tatong #1 LS: -0.21m LS: +1.3m LS: DPI8246 MS:-0.55m MS:+1.35m MS:DPI8261 US:-0.38m US:+1.88m US: DPI197 North East Lower Ovens Valley A gentle fall at the Lower terrace: +0.6 Key bores at the lower terrace lower terrace (-0.12 to +1.47 m. of the riverine plain: Bores to -0.18m), and a Upper Terrace: 0 to SOBN86887, 98867 and strong fall at the +0.17m 110738. Key bores at the upper terrace (-0.15 upper terrace: SOBN54981, to -0.24 m). 73832 and 99102 Rutherglen LS: - 0.43 to -0.5m LS: +0.15 to +0.18m LS: DPI11132, 11140 MS: -0.24 to -0.43m MS: -0.1 to -0.11m MS: DPI11138, 11340 US: -0.07 to -0.42m US: -0.11 to -0.14m US: DPI11341, 11342 Delay response (reading up to Oct10) Springhurst LS: -0.27 to -0.47m LS: +0.25 to +2.91 LS: DPI11033, 11019, 11052 MS: -0.2 to -0.25m MS:+0.30 to +0.37m MS: DPI11041, 11056 US: -0.36 to -0.4m US:+0.18 to +0.53m US: DPI11024, 11025 Indigo Valley LS: -0.10 to -0.17 m LS: +0.15 to +0.88 LS: DPI11109, 11114, 11119 MS: -0.08m MS:+0.07 m MS: DPI11112 East Bengworden GMSbores -1.33 -0.4 to +0.3m Bores:65762, 121802-121815, Gippsland to +0.5m 122466-122470

West Lake Wellington GMSbores (-10.0 -0.5 to +5.0m Bores:77910-77938, 50870- Gippsland to -0.23m) 50877, 112984-121802

Expl.bores (-21 to -1.0 to -0.8m 90366, 90400

-19m) 4110-4171 Woodside-Yarram GMSbores (-4.0 to -4.0 to +0.95m -0.20m) 104536, 105221, 110726 Expl.bores (-23 to -7.0 to -0.12m -8.3m) Port Phillip Phillip Island -7.5 to +1.0m -3.2 to +4.0m Bores: 12001, 12002, 12003, and Western 12004, 12015, 12671, 12672 Port Notes: #1. Hydrographs for these bores are provided in Appendix B.

In respect to future salinity risk in these priority provinces, the groundwater data indicates that the groundwater flow systems that drive dryland salinity process are quite responsive to climatic variability. While it is unlikely that the current wet phase can re-invigorate the salinity discharge features to the same levels as occurred during the eighties and nineties, the fact that quite a large number of discharge sites remained active during the drought must be remembered. The rapid response of most systems to the recent wet year also highlights the need to continue to monitor and manage these sites. Particularly where these provinces intersect significant biodiversity assets, gaining further insights into how such groundwater features in the landscape act as either threats or assets to those bioregions, needs further work.

Salinity Provinces in Victorian Bioregions – 2011 73

Salt export risks for priority provinces

Salt export risk arises where the downstream impact of salt discharged within the salinity province has consequences downstream. As a general rule, priority provinces north of the Great Dividing Range pose a more tangible risk due to the impact on Victoria’s salt loads to the Murray Darling Basin. Victoria’s obligations under the Basin Salinity Management Strategy (BSMS) are managed through a salt accounting procedure using a system of debits and credits underpinned by an agreed climatic period for hydraulic modelling (the 1975-2000 Benchmark Period). It includes an agreed cost function for the impacts of salinity and an accounting arrangement that takes account of the shared responsibility for the legacy of past action and the individual responsibility for the impact of future actions that cause the generation of salt loads (MDBC, 2007).

The main sources of salt load to the Murray River are from the Mallee, North-central, Goulburn-Broken and North-east Catchments. Only those catchments that have surface drainage connection (or direct aquifer connection in the case of the Mallee) to the Murray River contribute to the salt accounting, and so the identified priority provinces in the three surface-drained catchments have the highest salt export risk. The identified salinity provinces in each northern CMA (see table 36) are the areas of highest activity in respect to generating salt loads and so can be regarded as key provinces in which to maintain monitoring in order to inform salt export risk.

In Cheng et al 2011 (in draft), an analysis of groundwater trends for salinity observation bores in the Goulburn-Broken Catchment has confirmed that the recent dry decade caused a substantial decrease in the number of bores showing a rising trend, a decline in the magnitudes of rise in those bores still rising and increased rates of decline in falling bores. These results are to be used to review projected salt load generation rates under the agreed BSMS modelling methods.

For catchments south of the divide, salt export risk to downstream assets is much less defined and depends upon the nature of the receiving water bodies. For example, in the Corangamite catchment, the majority of high priority provinces drain to naturally saline water bodies. Only the Moorabool province poses a risk to river water quality (used for urban and agricultural supply), and there is little risk of increased salt loads posing a threat to environmental values. Likewise the Lake Wellington province in West Gippsland is not capable of generating salt loads capable of causing detrimental impact on Lake Wellington and the Gippsland Lakes ‘Flagship’.

The most recently available surface water trends report (SKM, 2007) identified that increasing trends tended to be mostly in western Victoria, in particular in the Wimmera, Glenelg-Hopkins and Corangamite regions, the western part of the Port Phillip region, as well as a number of locations in the North Central region. A few sites showed stronger rising salinity trends than many others in the Wimmera, Glenelg- Hopkins and Port Phillip regions and there were both increasing and decreasing trends within the North Central, Corangamite and Port Phillip region. Most of the eastern part of the state showed no significant direction of trend for electrical conductivity.

In respect to the salinity provinces, conclusions cannot be drawn from the above report (SKM 2007) as to the level of risk the priority provinces pose to the bioregions through salt load generation. Due to the drought, it is likely that stream salt loads decreased, but in-stream salinities may have increased due to less rainfall and dilution. This highlights the need to undertake more specific data acquisition and analysis at each priority province if better understanding of the consequences of salt loads on environmental assets is to be gained.

Salinity Provinces in Victorian Bioregions – 2011 74

6. Conclusions Priority salinity provinces

Based on the intersection of the newly defined salinity provinces with the Victorian “Flagships” and “Biolinks” (see Table 36), the most intersected, or highest preliminary priority “Flagship” areas (not in any order), are:- • Western Volcanic Plains • South West • Mega Murray • Goldfields

The most intersected “Biolink” area is clearly North and Central Victoria, although it covers a very large part of the State. It and others should be given greater importance wherever it or they occur adjacent to intersected “Flagships” (e.g. Upper Moorabool, Willaura, Pyrenees, Gunbower-Benjeroop, Dimboola).

The most significantly intersected CMA regions in terms of contained high value environmental asset areas threatened by salinity (not in any order) are:- • Corangamite • Glenelg-Hopkins • Wimmera • Mallee, and • North Central

Defining the priority salinity provinces provides a better starting point from which to target efforts to analyse and document consequences of landscape salinity on identified assets. The large scale maps and supporting information about the proposed priority salinity provinces in this report provide a higher view level of starting information. Any more specific information about the consequences of each salinity hazard on defined assets within each province is an order of magnitude more detailed task.

More detailed investigations to delineate such things as the proportions of primary versus secondary salinity, the potential to intervene (or manage the salinity) and determining the need and benefits of actions on the identified assets is probably best undertaken at a CMA scale. Within each CMA, it would then be necessary to focus on site specific assets (once they are delineated), as the intersection of salinity provinces with the ‘Flagships’ and ‘Bioregions’ is too imprecise to generate the detail required.

Salinity Provinces in Victorian Bioregions – 2011 75

7. Recommendations Dryland salinity presents an ongoing threat to catchment conditions in many parts of Victoria. However, evidence of salinity behaviour during the extremes of climate cycles of the last 15 years has led to a maturing understanding of the nature of salinity occurrence in the Victorian landscape (in it’s many forms and levels of impact). These recommendations are therefore based on a clearer understanding of the climate driven equilibriums and vegetation adaptations that govern salinity expression and consequence in the landscape. For both public and private land management in the state, delineation of salinity occurrence into low salinity, high salinity and priority provinces provides land managers at the range of scales (from paddock to CMA to DSE) with fundamental information upon which to base subsequent decisions. Recommendations for future R&D and usage of the salinity provinces concept are: • That higher resolution delineation of key environmental assets needs to be undertaken and collated by DSE and CMA’s in order to focus effort in answering questions of ‘future salinity risk; salinity impact and manageability’ with regard to the impact of salinity within each province on the identified assets. Initial risk/impact assessments to identify additional priority provinces will be required for any key assets that occur outside of 'Flagships' and 'Biolinks' • That the bore monitoring program needs to be adequately resourced, particularly in the high priority provinces so that reliable predictions of salinity risk can be made (once key assets are identified). • That the results of the province identification be used to guide decisions in the monitoring review so as to ensure available resources are directed appropriately. • That key, long-term discharge monitoring sites be maintained in representative priority salinity provinces and that long term monitoring is suitably resourced and targeted to meet the needs of catchment condition reporting and asset risk assessments. • For DPI Landscape and Water Science, and DSE where relevant, the salinity provinces be used as the future framework when undertaking subsequent research and investigation into salinity. • That relevant agencies involved in natural resource management planning and programs around the state be encouraged and assisted to incorporate the new salinity thinking and salinity province work into their NRM planning.

Salinity Provinces in Victorian Bioregions – 2011 76

8. References Salinity management plan references Avoca DCWG (1993). Avoca Catchment Salinity Management Plan – Draft. Prepared by Avoca Dryland Community Working Group, October 1993.

Avon-Richardson RLWMG (1992). Avon-Richardson Land and Water Management Plan – Draft. Prepared by Avon-Richardson Land and Water Management Group, October 1992.

Campaspe CWG (1992). Campaspe Catchment Salinity Management Plan – Draft. Prepared by Campaspe Community Working Group, December 1992.

Campaspe West SRWG (1989). Campaspe West – Planning for its future. Draft Salinity Management Plan. Prepared by Campaspe West Sub-Regional Working Group, August 1989. Salt Action Victoria.

Corangamite Salinity Forum (1992). Restoring the balance – A strategy for managing salinity in the Corangamite Salinity Region. Draft strategy prepared by the Corangamite Salinity Forum, December 1992. Salt Action Victoria.

DCE (1990). Draft Gippsland Lakes Management Plan. Prepared by Department of Conservation and Environment and assisted by Gippsland Lakes Consultative Committee, July 1990.

Delaney A. and Alexander J. (2007). North Central Dryland Region Management Plan – Draft. Prepared for North Central Catchment Management Authority.

EG CMA (2005). East Gippsland Regional Catchment Strategy – 2005-2010. East Gippsland Catchment Management Authority.

Glenelg Salinity Forum (1993). Salt assault! The Glenelg Region Salinity Strategy. Draft strategy prepared by the Glenelg Salinity Forum, Hamilton, Victoria. Salt Action Victoria.

Goulburn-Broken CMA (2002). Goulburn-Broken Dryland Salinity Management Plan – 1995-2001 Review. Draft second generation salinity management plan by Goulburn-Broken Catchment Management Authority.

Goulburn-Broken Region SPPAC (1989). Shepparton (Irrigation Region) Land and Water Salinity Management Plan. Draft report prepared by Goulburn-Broken Region Salinity Pilot Program Advisory Council (SPPAC), August 1989. Salt Action Victoria.

KLAWG (1991). The Kerang Lakes Area Management Plan – Preliminary Draft. Kerang Lakes Area Working Group, August 1991.

Loddon CWG (1992). Loddon Catchment Salinity Management Plan – Draft. Prepared by Loddon Community Working Group, November 1992.

Mallee Dryland CSWG (1992). Mallee Dryland Draft Salinity Management Plan. Prepared by Mallee Dryland Community Salinity Working Group, October 1992.

Mallee CALP Board (1997). Mallee Regional Catchment Strategy. Prepared by Mallee Catchment and Land Protection Board, June 1997.

McGowan International (1988). Dryland management plan – Land and water salinity in the catchment of Goulburn-Broken Rivers, Victoria. Stage II report, Volume 1, July 1988.

Nangiloc-Colignan CSWG (1991). Nangiloc-Colignan Draft Salinity Management Plan. Prepared by Nangiloc-Colignan Community Salinity Working Group, February 1991. Salt Action Victoria.

NESWG (1997). Reversing the trend – Draft North East Salinity Strategy. Prepared by the North East Salinity Working Group as a component of the North East Regional Catchment Strategy, December 1997.

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NERCLPB (1997). North East Regional Catchment Strategy. Prepared by the North East Regional Catchment and Land Protection Board, December 1997.

Nicholson C., Dahlhaus P., Anderson G., Kelliher C. and Stephens M. (2006). Corangamite Salinity Action Plan 2005-2008. Published by Corangamite Catchment Management Authority.

Nyah to the South Australian Border CSG (1992a). Protecting our river – Draft Salinity Management Plan background report. Prepared by Nyah to the South Australian Border Community Salinity Group, May 1992.

Nyah to the South Australian Border CSG (1992b). Protecting our river – Draft Salinity Management Plan supplementary report. Prepared by Nyah to the South Australian Border Community Salinity Group, December 1992.

PICSCG and DCNR (1992). Phillip Island Draft Salinity Management Plan. Prepared by Phillip Island Community Salinity Consultative Group and Department of Conservation and Natural Resources, October 1992. Salt Action Victoria.

PP&WP RCS (2004). Port Phillip and Western Port Regional Catchment Strategy 2004-2009. Port Phillip and Western Port Catchment Management Authority.

SKM (2002). Second Generation Dryland Salinity Management Plan for the North Central Region. Draft B, Unpublished.

SKM (2005). West Gippsland Salinity Management Plan 2005. Published by West Gippsland Catchment Management Authority.

Sunraysia CSWG (1991). Sunraysia Draft Salinity Management Plan. Prepared by Sunraysia Community Salinity Working Group, November 1991. Salt Action Victoria.

Wimmera CCG (1992a). Wimmera Catchment Salinity Management Plan. Draft report prepared by Wimmera Catchment Co-ordinating Group, November 1992. Salt Action Victoria.

Wimmera CCG (1992b). Wimmera River Integrated Catchment Management Strategy. Final report prepared by Wimmera Catchment Co-ordinating Group, December 1992. National Soil Conservation Program.

Wimmera CMA (2005). Wimmera Regional Salinity Action Plan 2005-2010. Prepared and published by Wimmera Catchment Management Authority.

Other references Cheng, X 1999 Goulburn-Broken Dryland Catchment Prioritisation – Upland sub-catchments. Centre for Land Protection Research Technical report No 58. Dept Natural Resources and Environment ISBN 0 7311 4344 2

Cheng, X., Reid, M. and Terry, A. (2006). Groundwater hydrograph behaviour in the South West Goulburn region. Research Report, Dept. Primary Industries, Victoria, Australia.

Cheng, X., Adelana M. and Reid, M. (2011, in draft). Groundwater trend and behaviour in the Goulburn and Broken dryland catchments. Research Report, Dept. Primary Industries, Victoria, Australia

Clark R. (2011, in draft). Remapping of soil salinity in Victoria in 2008 and 2009 to identify changes in its extent and severity since the late 1980s. Future Farming Systems Research Technical Report.

Clark, R. and Harvey, W. (2008). Dryland salinity in Victoria in 2007 – An analysis of data from the soil salinity database and Victorian discharge monitoring network. DPI technical report to DSE.

Clark, R., Harvey, W. and Williams, S. (2008). Analysis of attribute errors in the Victorian soil salinity GIS database in 2007. DPI technical report to DSE.

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Clifton, C. and Heislers, D. (2004). ASSALT: An asset-based salinity priority setting process. Final discussion paper prepared for North Central Catchment Management Authority, July 2004.

Coram, J., Dyson, P., and Evans, R. (2001). An evaluation framework for dryland salinity . For the National Land and Water Resources Audit 2001. Natural Heritage Trust. Land and Water Australia, Canberra, 113p.

Dahlhaus, P., Cox, J., Simmons, C. and Smitt, C. (2008). Beyond hydrogeologic evidence: challenging the current assumptions about salinity processes in the Corangamite region, Australia. Hydrogeology J 16: 1283-1298.

Dahlhaus, P., Evans, T., Nathan, E., Cox, J. and Simmons, C. (2010). Groundwater-level response to land- use change and the implications for salinity management in the West catchment, Victoria, Australia. Hydrogeology J 18: 7, November 2010 pp 1611-23

Dixon, P. (1989). Dryland salinity in a sub-catchment at Glenthompson, Victoria. Australian Geographer 20(2): 144-152.

Dunn, B. (1991). Salinity discharge mapping on two Western District Land Systems. Unpublished B.App.Sc. research project, Ballarat University College.

DWR (1986) Salinity in Victoria: Physical control options. Authors P Macumber and C Fitzpatrick for the Natural Resources and Environment Committee of cabinet. Department of Water Resources Victoria, report number 15. ISBN 0 7241 8375 2

Gill, B. C. (2004). Landscape scale hydrologic balance – can we find it? In Proceedings of 9th Murray- Darling Basin Groundwater Workshop. Bendigo, Victoria, Australia, 5 pages

Hekmeijer, P., Gill, B., Reid, M., Fawcett, J. and Cheng, X. (2008). Dryland groundwater monitoring review, 2006-07. Department of Primary Industries report to Department of Sustainability and Environment, Victoria. Australia.

Gill B, Fawcett J, Cheng X and Reid M. (2008). Review of benchmarking watertables for six Victorian CMA regions. Department of Primary Industries Victoria. ISBN 978 1 74217 060 2

DSE 2010. Land and Biodiversity White Paper 2010. Securing Our Natural Future, A white paper for land and biodiversity at a time of climate change. ISBN 978 1 74242 152 0

Macumber, P. G. (1991). Interaction between ground water and surface systems in Northern Victoria. Published PhD. Thesis. Dept. Conservation and Environment.

MDBC, 2007. Murray-Darling Basin Commission – Basin Salinity Management Strategy 2001-2015. Mid- term review. Final report. MDBC Publication No. 11/08. ISBN 978-1-921257-51-3

Mudd, G.M., Jelecic, S. and Ginnivan, F. (2006). Towards quantifying shallow groundwater-climate relationships in central and northern Victoria. In Proceedings of 10th Murray-Darling Basin Groundwater Workshop, Canberra, September 2006, 5 pages.

National Land & Water Resources Audit (NLWRA) (2001). Australian Dryland Salinity Assessment 2000. NLWRA, c/o Land and Water Australia, Commonwealth of Australia.

Reid, M. (2010). Impacts of prolonged dry climate conditions on groundwater levels and recharge in . In Transactions of the Royal Society of Victoria, Special Issue on North Central Victoria: A golden era, a changed ecosystem forever? Vol 122 (2): lxii-lxxv. ISSN 0035-9211. December 2010.

Reid, M. (2010). A project plan for Statewide Salinity Support to DSE in 2010-2011. Future Farming Systems Research report to Dept. Sustainability and Environment, October 2010.

Reid, M., Cheng, X. and Huggins, C. (2006). Using ground water responses to improve understanding of climate variation impacts and salinity risk. In Proceedings of 10th Murray-Darling Basin Groundwater Workshop, Canberra, ACT, Australia, September 2006, 9 pages.

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Reid, M., Cherry, D., Hekmeijer, P., Terry, A. and Dyson, P. (2009). Upper Campaspe catchment groundwater flow systems at 1:100,000 scale. Department of Primary Industries Report for North Central CMA.

Ridley, A., Pannell, D. and Park, G. (2006). SIF3 / INFFER, North-Central CMA

SKM (2005) Shallow Groundwater Flow Systems of the West Gippsland region and the implications for salinity management. Report prepared for the WG CMA and DPI.

SKM (2007) Victorian Water Quality Monitoring Network Trend Analysis – Update to 2005. Prepared for DSE.

SKM (2009). Mallee Catchment Technical Bulletin. Mallee Catchment Management Authority.

Sturmfels, C. (1988). Ballarat Region salinity control strategy (Draft). Department of Conservation, Forests and Lands, Ballarat.

Walker, G., Gilfedder, M., Evans, R., Dyson, P. and Stauffacher, M. (2003). Groundwater Flow Systems Framework – essential tools for planning salinity management. Murray-Darling Basin Commission Publication 14/03, Canberra.

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9. Appendices

Appendix A – Map outputs The first three maps divide the state of Victoria into thirds and show the State soil salinity mapping with the State ‘Flagships’ and ‘Biolinks’. (NOTE: for higher resolution copies of these maps, please contact DPI in Bendigo)

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The second set of three maps show the salinity provinces and CMA regions, with the priority salinity provinces highlighted in yellow.

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Appendix B – Example bore hydrographs Some representative bore hydrographs from priority salinity provinces in the Goulburn Broken catchment showing groundwater responses to the drought years and the recent wet seasons.

Priority Salinity Province: Warrenbayne – Boho

WARRENBAYNE Colluvium of Violet Town Volcanics '92 '94 '96 '98 '00 '02 '04 '06 '08 '10

0

-2

-4

-6

-8 Bore no. 300 -10 8453 -12 8454 Depth Depth to(m) waterlevel 8455 -14 Falling watertable in response to BOS tree plantation until 1996. Bores 8453, 8454 and 8455 are located at 5 m, 50 m and 100 m below Harrison's BOS tree plantation. Bore 300 is located on the lower slope of an untreated area nearby.

WARRENBAYNE Colluvium of Violet Town Volcanics '94 '96 '98 '00 '02 '04 '06 '08 '10 -1 Bore no. -3 8463 -5 8464 -7 -9 -11 -13

Depth to(m) waterlevel -15 -17 Both bores are located below Sadler's BOS tree plantation. Falling trends due to the BOS tree plantation and dry conditions. Very stong rise in response to the wet conditions since mid 2010

Salinity Provinces in Victorian Bioregions – 2011 85

WARRENBAYNE Riverine Plain & Colluvium '82 '83 '84 '85 '86 '87 '88 '89 '90 '91 '92 '93 '94 '95 '96 '97 '98 '99 '00 '01 '02 '03 '04 '05 '06 '07 '08 '09 '10 '11 -2

-4

-6 Bore no. 8420 8419 Depth to waterlevel (m) Depth to waterlevel 8418 -8 Steady rise until 1994 and stable since then on the plain immediately below an untreated Violet Town Volcanics Hills. Slightly rising trend until 1994 and gradual fall since then in the colluvium of Violet Town Volcanics

Priority Salinity Province: Molyullah - Tatong Molyullah Siluro/Devonian sediments

'87 '89 '91 '93 '95 '97 '99 '01 '03 '05 '07 '09 '11 -1

-2

-3

-4 Bore no. 8249 (Lower slope) Depth (m) to waterlevel

-5 Strong seasonal fluctuations, slightly rising trend in the late 1980s and early 1990s, then moderately falling trend up to mid 2010. Very strong response to the wet conditions in 2010.

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Molyullah Siluro/Devonian sediments

'87 '89 '91 '93 '95 '97 '99 '01 '03 '05 '07 '09 '11 0

-2

-4

-6 Bore no. 8261 (mid slope) Depth (m) to waterlevel

-8 Rising trend in the early 1990s, then gradually fell to record low in mid-2010. The response to the wet conditions in 2010 was uprecedentedly strong.

Molyullah Siluro/Devonian sediments

'87 '89 '91 '93 '95 '97 '99 '01 '03 '05 '07 '09 '11 -7 -9 -11 -13 -15 -17 -19 Bore no. 197 (upper slope)

Depth (m) to waterlevel -21 -23 Fluctuating watertable strongly responds to rainfall variation, the response to the wet conditions in 2010 was strong.

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