Surry Estuary Management Plan
Summary This management plan covers the Surry estuary downstream from the Woolwash gauging station at Heathmere to the mouth of the estuary at Narrawong. This management plan has been developed in consultation with members of the local community and government agencies and provides a basis for coordinated and targeted investment in the maintenance and enhancement of the values provided by the estuary for future generations.
Development of the management plan has focused on identification of the key assets provided by the estuary and the threats that are degrading, or have potential to degrade the value of the identified assets. This approach is consistent with the Glenelg Hopkins River Health Strategy. The assets and values identified in the Surry Estuary Management Plan include:
o Habitat The habitat assets provided by the estuary underpin cultural, social and economic values held by the local community. The estuary provides habitat to a range of species, including 12 species of fish, and 18 species of birds. o Water quality and quantity Good water quality and sufficient quantity is essential to maintain a healthy estuary and healthy habitats. o Social values Key social values at the Surry estuary include recreational fishing, camping and swimming. o Cultural values Because of its environmental attributes the Surry estuary has been highly valued throughout its history – from its original indigenous occupants through to the present inhabitants and visitors. o Economic values Economic values in the estuary management plan area include agriculture, commercial fishing and tourism.
The main threats to the estuary’s ongoing health are: o Inappropriate artificial river mouth opening; o Invasion and spread of pest plants and animals; o Reduced water quality and quantity; o Inappropriate development; and o Climate change and sea level rise.
Assessment of the threats posed to assets and determination of practical means to reduce or eliminate these threats has allowed formulation of management objectives and actions. Groupings of these management actions form a set of key programs that, when implemented, will provide significant benefits in terms of maintenance and enhancement of the values of the estuary. The following table provides a summary of the implementation programs that have been developed within this estuary management plan. It also includes links to actions identified in the Glenelg Hopkins River Health Strategy (GHRHS).
Development of this management plan fulfils one of the high priorities identified by the South West Estuaries Coastal Action Plan (Western Coastal Board 2002a), and contributes to Regional Management Action Target 83 in the Glenelg Hopkins Regional Catchment Strategy (RMAT 83: Meet aspirational target for coastal areas through developing and implementing individual estuary management plans in accordance with the South West Estuaries Coastal Action Plan .). Development of this estuary management plan also fulfils actions identified in the Glenelg Hopkins CMA River Health Strategy (Glenelg Hopkins CMA 2004).
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Table 1 Management objectives and targets developed for the Surry estuary
Program Management objective Target GHRHS Links Physical habitat – aquatic and No reduction, and if possible an Extent, condition and diversity of RH-P2-2, semi-aquatic increase in the extent, condition and representative habitat types is comparable diversity of all representative habitat to those recorded in 2007. RH-P2-3 types. Fish Demonstrated recovery of fish stocks An increase in the population size and from the fish kill in 2005 and previous number of year classes of black bream from events. those recorded in 2005. Water quality and quantity Achieve a standard of water quality Develop and apply water quality criteria and quantity that protects the diversity specific to the Surry estuary using the and abundance of aquatic ecosystems ANZECC Guidelines (2000). and allows recreational and aesthetic enjoyment of the estuary. Recreation Estuary continues to provide the full Water quality is maintained at a level safe range of recreational opportunities for recreation as per State Environment currently enjoyed by residents and Protection Policy 90% of the time. visitors. Cultural Protect the Aboriginal and non- No disturbance of all sites of archaeological indigenous heritage of the estuary. and heritage significance. Economic Estuary continues to provide the basis Quantification of the economic importance for sustainable economic use. of a healthy Surry estuary. Estuary entrance management Implement a management process for Establish a protocol for estuary mouth RH-P2-1 and artificial river mouth the estuary entrance that provides the opening using the estuary entrance decision opening best possible compromise between support system. the ecological requirements of the estuary and the social and economic requirements of the local community. Pathogens and parasites – fish Maintain healthy indigenous fish Maintain current agency endorsed response populations. plans for all reported incidents of pathogens and parasites. Pest plants and animals Reduction in the extent of listed weed Establish a baseline understanding of listed RH-P2-5 species. weed species. Climate change Incorporate new information on climate change as it comes to light into the management framework for the Surry estuary. Local government planning Direct and control development to The results of the Surry estuary flood study protect the values of the Surry estuary incorporated into the Glenelg Shire and continue economic development Planning Scheme. within the framework of ecological sustainability. Monitoring, evaluation and Monitor and evaluate the health and Undertake an evaluation of the reporting functioning of the estuary and implementation of the plan. implementation of the estuary management plan.
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Acknowledgements Members of the community who gave up their time to attend the workshop
Jodie Honan for providing the quote from G.E. Morrison
Members of the Coast and Marine Technical Working Group
Published by: Glenelg Hopkins Catchment Management Authority 79 French Street, Hamilton Victoria 3300
Disclaimer This publication may be of assistance to you but the State of Victoria and the Glenelg Hopkins Catchment Management Authority and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims any liability for any error, loss or other consequence that may arise from you relying on the information in this publication
ISBN:
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Abbreviations AAV - Aboriginal Affairs Victoria ANZECC – Australian and New Zealand Environment Conservation Council ASS - acid sulphate soil ARMO - artificial river mouth opening. CAMBA - China Australia Migratory Bird Agreement CE – Community engagement DCNR - former Department of Conservation and Natural Resources, now DSE DEH - Department of Environment and Heritage (Federal Government department). DIMIA - Department of Immigration, Multicultural and Indigenous Affairs (Federal Government department). DOI - Department of Infrastructure DPI -Department of Primary Industries DSE - Department of Sustainability and Environment DU - Deakin University DVC - Department of Victorian Communities EVC – ecological vegetation class EPA - Environment Protection Authority FSR – Flow stress ranking GHCMA - Glenelg Hopkins CMA GSC – Glenelg Shire Council IPA - Indigenous Protected Area ISC – Index of Stream Condition IUCN - World Conservation Union JAMBA - Japan Australia Migratory Bird Agreement LCC - Land Conservation Council MER – Monitoring, evaluation and reporting NHT – Natural Heritage Trust NTU – nephelometric turbidity unit OW – On-ground works PV - Parks Victoria SAC – Scientific Advisory Committee SDL – Sustainable diversion limit SEPP WoV – State Environment Protection Policy Waters of Victoria SP – Strategic planning SRW - Southern Rural Water TFN - Trust for Nature WCB - Western Coastal Board
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1. INTRODUCTION...... 1
1.1 GENERAL PRINCIPLES FOR ESTUARY MANAGEMENT ...... 1 1.2 THE VALUE OF THE SURRY ESTUARY ...... 1 1.3 A PREFERRED FUTURE FOR THE SURRY ESTUARY...... 1 1.4 A PRINCIPLE FOR MANAGEMENT OF THE SURRY ESTUARY INTO THE FUTURE ...... 2 1.5 MANAGEMENT PLAN STATUS...... 3 1.6 MANAGEMENT PLAN AREA ...... 3 1.7 POLICY FRAMEWORK ...... 5 1.8 MANAGEMENT PLAN DEVELOPMENT AND CONSULTATION PROCESS ...... 6 1.9 IMPLEMENTATION OF THE SURRY ESTUARY MANAGEMENT PLAN ...... 6 1.10 THE SURRY ESTUARY – FUNCTION AND CHARACTERISTICS ...... 7 1.10.1 Estuary processes and function...... 7 1.10.2 Surry estuary bathymetry...... 9 1.10.3 Land use and tenure...... 9 1.10.4 Catchment condition...... 9 1.10.5 Flora and fauna...... 10 Flora...... 10 Fauna ...... 10 Birds...... 10 Mammals...... 10 1.11 SOCIAL VALUES ...... 10 1.12 ECONOMIC VALUES ...... 11 Agriculture ...... 11 Tourism...... 11 Commercial fishing ...... 11 Recreational fishing...... 11 Ecosystem services ...... 11 1.13 CULTURAL VALUES ...... 11 Aboriginal...... 11 Non-indigenous ...... 12 1.14 PAST MANAGEMENT INITIATIVES ...... 12 Surry River Restoration Plan...... 12 Surry to the Sea ...... 13 2. KEY MANAGEMENT AREAS ...... 14
2.1 PHYSICAL HABITAT – AQUATIC AND SEMI -AQUATIC ...... 14 2.1.1 The importance of good habitat...... 14 2.1.2 Habitats in the Surry estuary ...... 14 2.1.3 What are the current threats to habitat in the Surry estuary?...... 14 2.1.4 What information is needed to improve management? ...... 14 2.1.5 What is the capacity to change habitats in the estuary? ...... 15 2.1.6 Management actions – aquatic and semi aquatic habitat ...... 15 2.2 FISH ...... 15 2.2.1 The importance of healthy fish populations ...... 15 2.2.2 Fish in the Surry estuary...... 16 2.2.3 What are the current threats to fish in the Surry estuary? ...... 16 2.2.4 What is the current condition of fish in the estuary?...... 16 2.2.5 What information is needed to improve management? ...... 16 2.2.6 What is the capacity to change fish in the estuary? ...... 17 2.2.7 Management actions – fish ...... 17 2.3 WATER QUALITY ...... 17 2.3.1 The importance of good water quality ...... 17 2.3.2 Water quality in the Surry estuary ...... 17 2.3.3 What are the current threats to water quality in the Surry estuary?...... 17 2.3.4 What is the current condition of water quality in the Surry estuary?...... 18 Nutrients ...... 18 Deoxygenation...... 19 E.coli...... 19 2.3.5 What information is needed to improve management? ...... 20 vi Surry Estuary Management Plan
2.3.6 What is the capacity to change water quality in the Surry estuary? ...... 20 2.4 HYDROLOGY (WATER QUANTITY )...... 21 2.4.1 The importance of hydrology...... 21 2.4.2 Hydrology in the Surry estuary...... 21 2.4.3 What are the threats to hydrology?...... 21 2.4.4 What is the current condition of flows in the Surry estuary? ...... 21 2.4.5 What information is needed to improve management? ...... 22 2.4.6 What is the capacity to change hydrology in the Surry estuary? ...... 22 2.5 ESTUARY ENTRANCE MANAGEMENT AND ARTIFICIAL RIVER MOUTH OPENING...... 23 2.5.1 Importance of estuary entrance management ...... 23 2.5.2 Estuary entrance management and artificial river mouth opening in the Surry estuary...... 23 2.5.3 What are the threats and risks of estuary entrance management and artificial river mouth opening? ...... 23 2.5.4 What is the current condition of estuary entrance management and artificial river mouth opening in the Surry estuary? ...... 25 Case studies ...... 26 Case study one – 2004 ...... 26 Case study two – 2005...... 27 Case study three – July 2006...... 28 Case study four – July 2007 ...... 29 2.5.5 What information is needed to improve management of the estuary entrance?...... 30 2.5.6 What is the capacity to influence estuary entrance management in the Surry estuary?...... 30 2.5.7 Management actions – estuary entrance and artificial river mouth opening...... 30 2.6 INUNDATION ...... 30 2.6.1 Why is inundation important?...... 30 2.6.2 Inundation at the Surry estuary ...... 31 2.6.3 What are the current issues related to inundation in the Surry estuary? ...... 31 2.6.4 What information is needed to improve management? ...... 31 2.6.5 What is the capacity to influence inundation in the Surry estuary? ...... 31 2.7 PEST PLANTS AND ANIMALS ...... 33 2.7.1 What is the importance of controlling pest plants and animals? ...... 33 2.7.2 Pest plants and animals at the Surry estuary...... 33 Pest plants...... 33 Divided sedge...... 33 Sea spurge ...... 33 Potentially threatening pest plants...... 33 Pest animals ...... 34 Rabbits ...... 34 Foxes...... 34 2.7.3 What is the capacity to influence the distribution of pest plants and animals?...... 34 2.7.4 Management actions – pest plants and animals...... 34 2.8 RESPONSE TO EMERGING ISSUES – FISH PATHOGENS AND PARASITES ...... 35 2.8.1 Why is response to emerging issues important? ...... 35 2.8.2 Fish pathogens and parasites in the Surry estuary ...... 35 2.8.3 Management actions – pathogens and parasites ...... 35 3. EXTERNAL FACTORS THAT WILL INFLUENCE MANAGEMENT OF THE SURRY ESTUARY...... 36
3.1 CLIMATE CHANGE AND SEA LEVEL RISE ...... 36 3.1.1 Why is this issue?...... 36 3.1.2 What are the implications for the Surry estuary? ...... 36 3.1.3 What can be done?...... 36 3.1.4 Management actions – climate change and sea level rise...... 37 3.2 LAND USE CHANGE ...... 37 3.2.1 Why is this issue?...... 37 4. LOCAL GOVERNMENT PLANNING...... 39
4.1 THE PLANNING SCHEME ...... 39 4.2 LOCAL PLANNING POLICY ...... 39 4.3 ZONES AND OVERLAYS ...... 39 Zones ...... 39 Overlays ...... 39 4.4 Landscape values...... 40 Surry Estuary Management Plan vii
4.5 ‘Sea change’ development ...... 40 4.6 Management actions – local government planning...... 40 5. ASSESSING THE EFFECTIVENESS OF THIS MANAGEMENT PLAN – MONITORING, EVALUATION AND REPORTING ...... 41
MONITORING ...... 41 EVALUATION ...... 42 REPORTING ...... 42 MANAGEMENT ACTIONS – MONITORING , EVALUATION AND REPORTING ...... 42 REFERENCES ...... 43
PERSONAL COMMUNICATIONS ...... 45 GLOSSARY ...... 46 FURTHER INFORMATION ...... 47 APPENDICES...... 48
APPENDIX A –NOTES FROM THE WORKSHOP HELD ON THE 19 TH JULY 2006...... 48 APPENDIX B – RELEVANT LEGISLATION , POLICIES AND STRATEGIES ...... 51 1.1. APPENDIX C - CONSULTATION FRAMEWORK FOR DEVELOPMENT AND IMPLEMENTATION OF ESTUARY MANAGEMENT PLANS ...... 53 APPENDIX D – ECOLOGICAL VEGETATION CLASSES ...... 54 Pre 1750 ...... 54 Current EVCs ...... 55 APPENDIX E – BIRD SPECIES RECORDED IN THE SURRY ESTUARY ...... 56 APPENDIX F – SURRY RIVER RESTORATION PLAN REVIEW ...... 59 APPENDIX G – FISH SPECIES RECORDED IN THE SURRY ESTUARY ...... 62 Fish usage of estuaries ...... 62 APPENDIX H – ESTUARY WATER QUALITY MONITORING ...... 64 APPENDIX I - STATE ENVIRONMENT PROTECTION POLICY GUIDELINES OF VICTORIAN ESTUARIES ...... 65 APPENDIX J – MAXIMUM DAILY FLOW (ML/ DAY ) RECORDED AT THE WOOLWASH GAUGING STATION FROM 1975 TO 2006...... 65 APPENDIX K – WORKS ON WATERWAYS AND COASTAL MANAGEMENT ACT CONSENT – ESTUARY ENTRANCE MANAGEMENT AND ARTIFICIAL RIVER MOUTH OPENINGS ...... 66 Works on Waterways permit...... 66 Coastal Management Act Consent...... 66 APPENDIX L – WORKS ON WATERWAYS PERMIT ...... 67
viii Surry Estuary Management Plan 1. INTRODUCTION 1. Introduction This Surry Estuary Management Plan provides a strategic framework for investment in maintenance and enhancement of the estuary’s values. Management of the estuary is particularly focussed on protecting assets (Section 2) through reducing threats (Section 3) to the long-term health of the estuary’s environmental, social and economic values.
Development of this management plan fulfils one of the high priorities identified by the South West Estuaries Coastal Action Plan (Western Coastal Board 2002), and is a step toward meeting Regional Management Action Target 83 in the Glenelg Hopkins Regional Catchment Strategy (RMAT 83: Meet aspirational target for coastal areas through developing and implementing individual estuary management plans in a000ccordance with the South West Estuaries Coastal Action Plan .). Development of this estuary management plan also fulfils actions identified in the Glenelg Hopkins CMA River Health Strategy (Glenelg Hopkins CMA 2004) and furthers the work of the Surry River Restoration Plan (SKM 2000).
1.1 General principles for estuary management Guiding principles for estuary management for the Glenelg Hopkins Region have been established by the South West Estuaries Coastal Action Plan (Western Coastal Board 2002). These principles have been adopted with minor revision as follows:
1. The present generations have a basic duty of care, to ensure that the health and diversity of the environment is maintained or enhanced for the benefit of future generations. 2. Ecosystems (including estuaries), and the individual life forms and natural processes that underpin ecosystems have by their very nature, value in their own right.
These principles form the foundation of Glenelg Hopkins CMA’s approach to estuary management, and have been considered in the development of actions for the Surry estuary.
1.2 The value of the Surry estuary The social, economic and cultural benefits that human society currently enjoys are dependent on the health of the environment. The value of the services provided by ecosystems, including estuaries, is very high. Calculations of the dollar value of services provided by major ecosystems around the world have rated estuarine ecosystems as providing some of the highest value in terms of the return to human society on a per hectare basis (Costanza, d'Arge et al. 1997; NLWRA 2002). This is because of the highly productive nature of estuaries and their role in supporting fisheries, the range of species they support and the function of estuaries in absorbing nutrients and pollutants before they can reach the oceans. The high value of estuaries is also evident at a local scale. Townships, enterprise and social activities have developed around estuaries to take advantage of the services that they provide.
Recreational fishing is one of the many examples of ecosystem services and social and economic values depending on a healthy environment. Recreational fishing requires healthy fish stocks, which are dependent on healthy fish habitat. Strong recreational fisheries support tourism and other economic activities that benefit local communities.
The health of the Surry estuary underpins the social, cultural and economic values of the Narrawong community.
1.3 A preferred future for the Surry estuary The first step in the development of this management plan was a community workshop held at the Narrawong Hall on the 19 th of July 2006 (Appendix A). At this workshop, the local community expressed views on what the future should hold for the Surry estuary. The workshop produced a number of statements presented a range of community views on the preferred future of the estuary. These statements, or preferred futures, provided the Glenelg Hopkins CMA with an indication of how people who live near and use the estuary would like to see the estuary in the future. These preferred futures were prioritised as part of the workshop and the top three are presented below:
Access to the beach reserve, amenities etc. The river remains open so that the tidal movement keeps the river oxygenated rather than becoming stagnant.
Hopefully a healthy river left alone and problems of sewage and roads are fixed – we work around the river, not alter the river, and our children, grandchildren etc are able to enjoy a healthy river.
Surry Estuary Management Plan 1 1. INTRODUCTION The river makes us feel okay about the environment – the fish and the birds are telling us that there is a future.
Each of these statements demonstrates the strong community desire to see the estuary maintained as a healthy and vibrant natural resource for generations to come, and the differing perceptions of what “healthy” means. Each statement needs to be considered in the context of current legislative and physical constraints to estuary management and the general sustainable estuary management principles adopted for the Glenelg Hopkins Region.
Aspects of these vision statements do not align with each other, or with current legislation. One of the key functions of this management plan is to balance the desires of the community with the needs of the estuarine ecosystem and legislative requirements to develop management objectives, targets and actions to protect and enhance the environmental, social, economic and cultural assets of the Surry estuary. The following discussions highlight some of the inconsistencies and constraints to fully adhering to only one of the visions identified above.
The river remains open and tidal Seasonal closure of the Surry estuary through the build up of sand at the entrance is a natural occurrence, and occurs in many other estuaries across southern Australia. The diaries of the earliest European settlers demonstrate that the process of seasonal closure and reopening of estuary mouths in Victoria has occurred at least since European settlement. Maintaining the estuary mouth in an open condition would cause drastic changes in the ecology of the estuary. The works required to do this would require approval under the Coastal Management Act 1995, the Water Act 1989 , and the Planning and Environment Act 1987, which is unlikely. Environmental Significance Overlay 1 in the Glenelg Shire Planning Scheme covers the mouth of the estuary; the primary objective of this overlay is to ensure the long-term protection of coastal and marine environments. Altering the estuary from its natural state does not meet this objective.
It is unlikely that tidal influence would have a significant impact on water quality within the estuary. The coastline of southwest Victoria is microtidal; that is, there is a difference of less than one metre between low and high tides. This indicates that tidal intrusion would not be sufficient in improving the water quality in the estuary.
Leaving the river alone Since the arrival of Europeans in Australia there have been significant changes to the landscape, many of which have had a negative impact on the estuary’s health. One of the greatest impacts on the Surry estuary has been the development of infrastructure on the estuary floodplain. Historically, the estuary was managed to protect infrastructure and private property from inundation and as such development has increased. Ceasing all intervention now will not protect existing infrastructure. Steps need to be taken to improve infrastructure and reduce the risks associated with high water levels. Specific infrastructure issues include the inundation of Caravan Park Road, operation of the Caravan Park septic system and access to the boat ramp.
Rather than leaving the estuary completely alone, a more realistic future would be one in which management intervention decreases with time as infrastructure is improved and risks mitigated. In the interim, management needs to be well planned and less reactive to reduce the frequency and impacts of intervention.
Although very different overall, the preferred futures identified by the community have several positive themes in common. All have identified: • The importance of maintaining estuary health • The importance of access • The importance of the wildlife that the estuary supports
These themes provide a basis upon which an overarching management principle for the Surry estuary has been developed.
1.4 A principle for management of the Surry estuary into the future In light of the preferred futures and Glenelg Hopkins CMA’s role in protecting estuary health, this plan adopts the following principle for the management of the Surry estuary.
Protect and enhance the environmental, social and economic value of the Surry estuary and its surrounds into the future, while reducing the requirement for intervention over time.
2 Surry Estuary Management Plan 1. INTRODUCTION 1.5 Management plan status This management plan forms a sub-strategy of the Glenelg Hopkins River Health Strategy (2004) and has been developed according to provisions of the Water Act 1989 Section 189 (a) to (d).
1.6 Management plan area This management plan covers the estuarine reach of the Surry River downstream of the streamflow gauging station at a point known as the Woolwash downstream to the river mouth at Narrawong, shown in Figure 1.
Although this plan has been developed specifically for the estuary, the relationship between the health of the estuary and the up-stream catchment is recognised. Up-stream activities, actions and adjacent land-use have a significant influence on the estuary’s health. Reference to actions required outside the boundary of this management plan are made where the influence of wider catchment activities has not been adequately dealt with by existing strategies and plans.
A number of other strategies and plans are in place, which address issues higher in the catchment upstream, including the Glenelg Hopkins CMA River Health Strategy (2004) and the Glenelg Hopkins Nutrient Management Strategy (Glenelg Hopkins CMA 2002). This estuary management plan does not seek to repeat the work of other strategies and plans.
Surry Estuary Management Plan 3
Figure 1 – Estuary management plan area 4 Surry Estuary Management Plan
1. INTRODUCTION
1.7 Policy framework The Victorian Coastal Strategy (2002) and the South West Estuaries Coastal Action Plan (Western Coastal Board 2002) outline a suite of relevant government legislation and policy that directs the management of estuaries and estuarine wetlands.
A range of plans and strategies exist at the regional level that provide for the protection and enhancement of natural and cultural values of estuaries. Victoria has a strong natural resource policy framework and as a result these plans and strategies have a high level of integrated planning and address many aspects of sustainable use (see Figure 2). These plans and strategies, along with relevant legislation are presented in Appendix B.
The Victorian Coastal Strategy (2002) is especially relevant to this estuary management plan. It was endorsed by the State Government in 2002 and establishes the overall framework for the planning and management of the Victorian coast. The aim of this strategy is to ensure that Victoria’s coastal and marine environment continues to be well managed and used by present and future generations. The Victorian Coastal Strategy (2002) directly impacts on all coastal Crown land.
Implementation of the Strategy is undertaken through Coastal Action Plans (CAPs) which allow for the broad principles and strategies identified at the state level, to be further developed and applied at a regional level. Regional Coastal Action Plans of relevance to the Surry estuary include the Glenelg Coastal Action Plan (Glenelg Shire Council 2002), the South West Victoria Regional Coastal Action Plan (Western Coastal Board 2002) and the South West Estuaries Coastal Action Plan (Western Coastal Board 2002).
The Glenelg Shire Coastal Action Plan (2002) is consistent with both the South West Regional Coastal Action Plan (Western Coastal Board 2002) and the South West Estuaries Coastal Action Plan (Western Coastal Board 2002) in recommending the development of a management plan for the Surry River Estuary.
The South West Victoria Regional Coastal Action Plan (Western Coastal Board 2002) includes recommendations for coastal and marine areas between Breamlea and the South Australian border. It also establishes the need for a Coastal Action Plan specific to estuaries, which resulted in the development of the South West Estuaries Coastal Action Plan (Western Coastal Board 2002).
The South West Estuaries CAP (Western Coastal Board 2002) provides a regional framework to “ facilitate the development and implementation of individual estuary management plans” (Western Coastal Board 2002). The Surry Estuary Management Plan has been developed according to the principles set out in this CAP, and therefore seeks to address those objectives of the Victorian Coastal Strategy (Victorian Coastal Council 2002) that relate to this estuary.
In addition to fulfilling the strategic direction established by the abovementioned documents, the Estuary Management Plan also defines actions, which are consistent with and contribute to the implementation of the Glenelg Hopkins River Health Strategy 2004 (Glenelg Hopkins CMA 2004). The Surry estuary comprises part of the P2 sub-catchment, as defined by the River Health Strategy (Glenelg Hopkins CMA 2004).
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1. INTRODUCTION
Legislation that directly impacts on estuary management Legislation that underpins estuary management plans. Coastal Management Act 1995
Flora and Fauna Guarantee Act Victorian Coastal 1988 Water Act 1989 Strategy Catchment and Land Protection Act 1994
Victorian River Health Strategy South West Coastal Action Plan Victorian Biodiversity Strategy Glenelg Hopkins Regional Catchment Strategy Glenelg Hopkins River Health
Strategy South West Estuaries Coastal Action Plan
Surry Estuary Management Plan
Figure 2 - Key legislation and policies that influence management of the Surry estuary
1.8 Management plan development and consultation process Development of the management plan commenced in July 2006, and was funded through the Federal Government’s Natural Heritage Trust (NHT) and National Action Plan for Salinity and Water Quality (NAP) initiatives. Consultation with agency and community stakeholders began in March 2006. Details of the consultation are included in Appendix A. Appendix C shows the various stakeholders, both community and agency, and how they have been involved in the consultation process and their role in development of the plan.
1.9 Implementation of the Surry Estuary Management Plan The effectiveness of implementation of this plan needs to be regularly assessed using principles of adaptive management. That is, management needs to reflect changes in priorities that may become evident through the availability of improved information.
Three factors will govern implementation of this plan and investment in the health of the estuary: • Community attitude towards use and management of the estuary as a natural resource that should be preserved for future generations • The alignment of priorities for investment identified by this plan with those established for investment of State and Federal funding by the Glenelg Hopkins Regional Catchment Strategy and the Glenelg Hopkins River Health Strategy
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1. INTRODUCTION
• The alignment of priorities for investment identified by the plan with those of the lead agencies identified for individual actions including State government agencies, local government and the community.
1.10 The Surry estuary – function and characteristics The Surry estuary is a seasonally closed salt wedge estuary that extends approximately 10 kilometres upstream from the mouth at Narrawong (Mondon, Sherwood et al. 2003). An estuary is the mixing place of seawater and freshwater that flows off (or through) the land areas of the catchment, therefore the extent of an estuary at a particular point in time is entirely dependent on the amounts of freshwater and seawater flowing into it.
1.10.1 Estuary processes and function Estuaries are defined as “a partially enclosed coastal body of water which is either permanently or periodically open to the sea, and within which there is a measurable variation of salinity due to the mixture of sea water with freshwater derived from land drainage ” (Day 1980).
Many of the processes that occur in estuaries are related to inflows, both tidal and riverine. This includes stratification of water in the estuary, which occurs due to the higher salt content of seawater, which makes it denser than freshwater. This difference in density means that when seawater enters estuaries it flows in along the bottom and wedges underneath the freshwater. This creates layers of different water quality, with very little mixing in between. The estuarine hydrological cycle is shown in Figure 3.
As there is very little mixing between the two layers, once freshwater flows have decreased and the mouth is closed, oxygen in the bottom saltwater layer can be used up over time. There are a number of ways that dissolved oxygen can be consumed or lost from water, including respiration of aquatic plants, animals, and aerobic bacteria; diffusion back into the atmosphere; chemical oxidation processes; and as an export in outgoing flows. Over time these bottom waters can become deoxygenated, which means that more oxygen is being used up than can be replaced. Oxygen can be replaced in water through photosynthesis of aquatic plants; direct diffusion from the atmosphere; turbulent aeration and through tidal and freshwater inflows. The process of aerobic decomposition of organic matter uses oxygen. If there is no oxygen present then decomposition becomes anaerobic, which means that it is done without oxygen. This leads to the production of hydrogen sulphide, which is commonly known as rotten egg gas due to its smell.
Seasonal closure of the estuary entrance is another estuarine process that is related to inflows. Seasonal closure is a natural process, and occurs in estuaries throughout southern New South Wales, Victoria, Western Australia and even South Africa (Barton and Sherwood 2004). Within the Glenelg Hopkins CMA region six of the eight estuaries close on a seasonal basis; the other two are maintained permanently open. G.E. Morrison, who walked through Narrawong on his way to Adelaide in early 1880, described the Surry estuary as having “ a most extraordinary course. From the bridge it was seen to flow first almost due east, then to turn sharp round and flow almost west, til it was brought up on the beach by a sandbar” (Duruz unknown date). Morison also described the banks along the estuary as being “low and marshy” and described a freshwater spring that was located near the bridge (Duruz unknown date).
Seasonal closure of the estuary entrance is also linked to offshore sand transport as well as river flow (see Figure 4) and is most likely to occur during low flow periods (see Figure 3). Sand is continually deposited at the estuary entrance by waves, and then flushed out by river flow. During periods when freshwater inflow is low, sand builds up and creates a bar that remains there until river flows increase enough to remove it or the bar is artificially breached.
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1. INTRODUCTION
Figure 3 – Estuarine hydrological cycle (EEMSS 2006)
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1. INTRODUCTION
Figure 4 – Factors contributing to estuary mouth status (EEMSS 2006) 1.10.2 Surry estuary bathymetry Water depth in the Surry estuary is highly variable. At its deepest spot, the Surry estuary is only 4.2m deep, with much of the estuary less than 1.3m deep (Figure 5) (Ball and Blake 2007).
Figure 5 – Bathymetry of the Surry estuary, between 0 and 6000m upstream
1.10.3 Land use and tenure Agriculture is the predominate land use within the catchment, with 50.5% of land being used for agricultural practices (Mondon, Sherwood et al. 2003). Forestry occurs over 43% of the catchment, while 6% of land in the sub catchment is reserved for nature conservation purposes (Mondon, Sherwood et al. 2003). The remaining land in the catchment is used for urban or other land uses.
1.10.4 Catchment condition The Glenelg Hopkins CMA River Health Strategy defines the Surry River Catchment (P2) as a high priority catchment due to its high environmental assets (Glenelg Hopkins CMA 2004). The Surry River has its headwaters in the Cobboboonee State Forest, before flowing 46.4 kilometres to the sea at Narrawong (Mondon, Sherwood et al. 2003). The condition of the Surry River upstream of the estuary was assessed in 2004 as part of the Index of Stream Condition (ISC). This found that the river was in poor to moderate condition, however water quality was found to be good (Department of Sustainability and Environment 2005).
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1.10.5 Flora and fauna The Surry estuary and surrounding area provides home to a range of species. Some of the flora and fauna of the surrounding area is outlined below.
Flora Information on the native vegetation, including distribution maps of the ecological vegetation classes, is included in Appendix D.
The riparian zone, which is considered to be land adjoining or directly influencing the water body, is important in maintaining a healthy waterway. Good vegetated riparian zones can improve grazing productivity and provide shelter for stock. Riparian vegetation can also contribute to a decrease in erosion and improve water quality as it acts as a filter (Price, Lovett et al. 2004).
Revegetating the riparian zone of the Surry River was identified as a medium priority action in the Surry River Restoration Plan (SKM 2000). Since then the Surry River has been the focus of a major revegetation project (Glenelg Hopkins CMA 2002). Ninety percent of private estuary frontage has been fenced, as has 75% of private river frontage upstream of the estuary (Glenelg Hopkins CMA 2002).
Fauna Birds A total of 154 species of birds have been observed at the Surry estuary and are presented in Appendix E. Birds observed within the estuary include 13 species listed under the State Flora and Fauna Guarantee Act 1988 , one species listed under the China-Australia Migratory Bird Agreement (CAMBA); and two species listed under both CAMBA and the Japan- Australia Migratory Bird Agreement (JAMBA).
Mammals Swamp wallabies ( Wallabia bicolor ) have been recorded in the area.
1.11 Social values The estuary management plan workshop held on the 19th of July 2006 identified a range of social values that occur in and around the Surry estuary (Appendix A). Social values include fishing, swimming, boating, dog walking and exercise. Other social and recreational values that have been identified include bird watching and duck hunting (SKM 2000). Facilities for recreational use in the area include a boat ramp and barbeques located in the Narrawong Foreshore Reserve. Camping facilities are available at the Narrawong Caravan Park, which is situated on the banks of the estuary.
Recreational fishing has been highlighted as a popular social activity, although the level of use by recreational anglers is unknown. Shore based recreational fishing is restricted within the management plan area to the area near the mouth, as much of the estuary is bordered by private property.
Recently there has been increased interest in jetty construction along the Surry estuary. The primary purpose of these facilities is to improve recreational access and opportunities at the Surry estuary. There are a number of factors that need to be taken into account when considering new recreational facilities adjacent to the estuary to ensure the preservation of existing values.
One of the biggest threats to recreation and other social values at the Surry estuary is inappropriate facilities. This includes facilities that are inappropriately designed or constructed and cannot cope with the changing conditions in the estuarine environment, particularly the variable water levels that occur as a result of seasonal closure of the estuary entrance.
In other estuaries, such as the Hopkins estuary at Warrnambool, inundation of some jetties following closure of the estuary entrance results in them being unsafe for use for a period of time. The amount of time jetties are unable to be used depends on how long it either takes the estuary to meet the criteria set for an artificial river mouth opening, or for the estuary to open naturally. 10 Surry Estuary Management Plan
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Jetties should be constructed as floating rather than fixed structures in any seasonally closed estuary such as the Surry. When considering the design of floating jetties, results from the Surry estuary flood study will provide valuable information on the likely range of water levels they need to accommodate. Floating jetties have the added advantage of not only being functional at a range of water levels, but also in reducing the pressure to artificially open the estuary mouth.
Construction of jetties requires a permit issued under the Water Act 1989 as they are considered to be Works on Waterways. Glenelg Hopkins CMA is the responsible authority for regulating works on waterways. Under Glenelg Hopkins CMA Waterways Protection By-Law No. 1, any works in, on or around a designated waterway require a permit from the CMA
1.12 Economic values Agriculture In the Glenelg Hopkins region, agriculture for the period of 1999 to 2000 had a total turnover of $650 million and employed around 6,800 people (Green Triangle Regional Plantation Committee 2002 cited in Glenelg Hopkins CMA 2003). The economic value of agriculture within the area covered by this management plan is unknown and needs to be quantified.
Tourism Very little information is available on the total value of tourism to the Narrawong community. The Glenelg Shire Strategic Tourism Plan (Glenelg Shire Council 2005) highlights the lack of research on the value of tourism to the Glenelg Shire.
Commercial fishing Within Victoria, commercial eel fishing has a value of between 1.4 and 4.7 million dollars per year (Allen, Midgley et al. 2002). Four commercial licenses are able to take eels from the Surry estuary downstream of the Princes Highway Bridge (Allen, Midgley et al. 2002).
Recreational fishing Like commercial fishing, recreational fishing can also generate an economic benefit. A survey of recreational fishing conducted in 2001/2002 found that the average Victorian angler spent $721 on recreational fishing throughout this period (Henry and Lyle 2003), and that state-wide a total of almost $397 million was spent (Henry and Lyle 2003). The economic value of recreational fishing in the Surry estuary is unknown, as is the level of recreational fishing pressure.
Ecosystem services Ecosystem services can be defined as: “ those public good services, which generally come from natural areas, but which can also result from sustainable management of land and water. Included are provision of clean air and water, biodiversity services and the sequestration of carbon. There are services that benefit many, not only the producer” (VCMC and DSE 2003).
One study valued the services that a range of ecosystems provide and found that estuaries were the most valuable (Costanza, d'Arge et al. 1997), providing services worth $39,000 per hectare per year (Costanza, d'Arge et al. 1997; NLWRA 2002). This valuation was based on the use values of the system, which included factors such as nutrient cycling, but did not attempt to value the non-use values, such as spiritual and cultural values of the ecosystem.
Applying this figure of $39,000 per hectare per year to the Surry estuary, which has a total surface area of 15 hectares would mean that the Surry estuary provides ecosystem services of approximately $585,000 per year. This figure does not include any of the wetlands that are attached to the estuary.
1.13 Cultural values Aboriginal Konung was the name of the Surry River where it joined the sea (each section of river had its own name). Historically the Kilcarer gunditj was the clan that occupied this coastline stretching from the river to Portland and north towards Mt Clay. Their country was rich in ocean, estuarine, wetland and terrestrial resources. Numerous springs fed into the Surry River
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1. INTRODUCTION ensuring high water quality. However, this area was the first to be permanently occupied by the whalers from Tasmania with devastating effect on indigenous cultural practices.
Native title for the Gunditjmara people was declared in March 2007 and recognises the continuing connection of the Gunditjamara people to their traditional lands - from the Glenelg estuary to the Shaw River. Gunditj Mirring Traditional Owners Corporation has been proclaimed as the first Registered Aboriginal Party in Victoria under the Aboriginal Heritage Act 2006 which provides for the protection of Aboriginal cultural heritage
Non-indigenous Nearby Portland was the first settlement in Victoria (1834). William Dutton, the first European to permanently settle, in 1833 lived in his house to the west of the estuary of the Dutton River, as it was known until Mitchell renamed it in 1836. He harpooned the first and the last of the commercially caught whales along this coastline in the first half of the 1800s. His land extended to Henty’s Convincing Ground whaling station, also in Kilcarer country. A wharf was built in the mid-section of the estuary and the river used for transport (Glenelg Hopkins CMA 2002). The Campbell family manually scoured wool in the river at the “Woolwash” from the late 1800s to 1914 (Glenelg Hopkins CMA 2002), immediately upstream of the estuary.
The Victorian Heritage Register lists two shipwrecks that have occurred in the nearby area, including the wreck of the Julia in 1863. The Victorian Heritage Inventory lists a number of places in the Narrawong area that are considered to be significant including the Narrawong Homestead, the Woolwash, the Narrawong Sawpit and the Surry River.
1.14 Past management initiatives Significant management initiatives completed for the Surry River and estuary include:
Surry River Restoration Plan The Surry River Restoration Plan was developed by Sinclair Knight Merz (SKM) for the Western Coastal Board. It was finalised in 2000 and provided a five-year whole of catchment plan for the Surry River, including consideration of the estuary area.
Broad areas for consideration of issues identified by the plan include: o Biodiversity conservation o Water quality o Waterway condition o Cultural heritage o Recreation o River mouth and estuary flooding o Development o Catchment management
A review of the implementation of the Surry River Restoration plan was undertaken by Glenelg Hopkins CMA as the first step in developing this management plan for the Surry estuary. Details of this review are provided in Appendix F. Much has been learnt since the development of the Surry River Restoration Plan (SKM 2000) and it is necessary that plans are updated to ensure that decisions are based on the best information.
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Surry to the Sea A major action in the Surry River Restoration Plan was implemented and achieved by the Surry to the Sea project. Initiated by the Surry River Landcare Group in 2001-2002, the focus of this project was to re-establish native vegetation corridors along the length of the Surry River. The project was highly successful with 90% of private estuary frontage and 75% of private river frontage upstream of the estuary fenced and revegetated. An example of one of the revegetation areas is shown in Figure 6.
The project involved a coordinated effort between community groups, individuals and the Glenelg Hopkins CMA and was funded by both the State and Federal Governments.
Figure 6 - One of the Surry to the Sea revegetation areas in 2007
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2. Key management areas 2.1 Physical habitat – aquatic and semi-aquatic 2.1.1 The importance of good habitat Habitats are complex assemblages of biological, geological, hydrological and sometimes artificial (of human manufacture) components. The protection of habitat and its associated values is integral to a healthy estuary. Without healthy habitats it is difficult to protect and enhance the species and populations that depend on them. Therefore, the long-term sustainability of systems as a whole depends on the health of habitats. Habitats associated with estuaries include seagrasses, riparian vegetation, wetlands and their diverse vegetation, floodplains and substrates such as submerged wood, sand and mudflats. Seagrass, or submerged aquatic vegetation, is important for a range of reasons. It can provide habitat for a range of aquatic species, like fish and invertebrates, and may even be essential for some life history stages.
2.1.2 Habitats in the Surry estuary Mapping of the aquatic and fringing habits of the Surry estuary was carried out in early 2007, but prior to this very little was known about the seagrass in the Surry estuary. During the project four species of submerged aquatic vegetation were been recorded in the estuary, including Zostera muelleri, a species of Ruppia , Stuckenia pectinata and one species of charophyte algae ( Lamprothamnium succintum ). Charophyte algae have been found to form a dense mat in the upstream area of the estuary that can be up to 30cm thick in some locations.
Vegetation around the estuary is also significant. Mapping of the fringing vegetation has identified nine different ecological vegetation classes (EVCs), all of bioregional conservation significance. These are listed in Table 2 and their distribution displayed in map form in Appendix D. Some of the vegetation classes were not in good condition, suffering the impacts of stock grazing and weed infestation. Of particular concern at the Surry estuary is Carex divisa , also known as divided sedge, which is a pest plant that has seriously degraded the brackish wetland EVC. More information on divided sedge is presented in Section 2.7.
Table 2 – Ecological vegetation classes mapped at the Surry estuary in 2007 (Sinclair and Sutter 2007)
EVC Bioregional Area (Ha) conservation status Brackish wetland (aggregate EVC 656) Endangered 0.2 Estuarine reed bed (EVC 952) Endangered 19.5 Estuarine wetland (EVC 10) Endangered 1.2 Gahnia sedgeland (EVC 968) (Estuarine community) Endangered 1.6 Gahnia sedgeland (EVC 968) (Brackish heath community) Endangered 2.6 Spike-sedge wetland (EVC 819) Endangered 0.2 Swampy riparian woodland (EVC 83) Endangered >1.4 Swamp scrub (Freshwater) (EVC 53_61) Endangered 1.4 Tall marsh (EVC 821) Endangered 3.3
2.1.3 What are the current threats to habitat in the Surry estuary? Threats to the aquatic and semi-aquatic habitat values include: • altered flooding regime due to artificial river mouth opening • climate change and sea level rise • erosion and sedimentation • poor water quality • pest plants, particularly divided sedge
2.1.4 What information is needed to improve management? In order to improve management of the habitats in the Surry estuary, a monitoring program is required to ensure that any changes in condition or area of habitats can be readily detected.
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Although there is now a good understanding of the vegetation habitats in and around the Surry estuary, there is limited understanding of the importance of other types of habitats, like sand flats and snags. This information is currently not essential; however the value of these types of habitats does need to be considered.
2.1.5 What is the capacity to change habitats in the estuary? The capacity, or ability, to protect habitats in the Surry estuary, is reasonably good, provided that a rapid response to emerging issues, particularly pest plants, is maintained. Rapid response requires regular monitoring to allow for early identification of the establishment of new pest plant species.
Protecting habitats from the impacts of climate change is much more problematic. It requires that plants have space available to laterally migrate in response to both higher water levels and possible erosion. This can be achieved through the local planning scheme. Other solutions to address climate change are best undertaken on a national and international level.
2.1.6 Management actions – aquatic and semi aquatic habitat Habitat – aquatic and semi-aquatic Management objective : No reduction, and if possible an increase in the extent, condition and diversity of all representative habitat types.
Management action target : Extent, condition and diversity of representative habitat types is comparable to those recorded in 2007. Action No. Action Key Lead Priority Implementation Agency Tool SH1 Work with landholders to protect and rehabilitate OW GHCMA VH estuarine related habitat SH2 Complete a habitat risk assessment based on overlaying SP GHCMA VH the estuarine habitat maps and condition data with flood study mapping, cadastral mapping, development plans and other threat information. SH3 Develop a prioritised and costed estuarine habitat SP GHCMA VH protection and enhancement investment plan depending on the outputs from habitat risk assessment. SH4 Establish habitat reference sites and monitoring program MER GHCMA H to: • monitor the condition of aquatic and semi-aquatic vegetation • enable reporting against the estuarine habitat Resource Condition Target. SH5 Develop/identify indicators of condition for aquatic and MER DSE H semi-aquatic estuarine vegetation for use in monitoring progress towards achieving the resource condition target. SH6 Implement a communications process to convey the CE GHCMA H broad outcomes of the estuarine habitat mapping to the community and other management agencies.
2.2 Fish 2.2.1 The importance of healthy fish populations Healthy fish populations are important for a range of reasons. Fish can be recreationally important, but they can also be an indicator of how the estuarine ecosystem is functioning. That is, a healthy fish population can indicate that there is a healthy supporting environment.
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2.2.2 Fish in the Surry estuary Thirteen species of fish have been recorded in the Surry estuary, and are presented in Appendix G. Fish found in estuaries can include non-estuarine species, which includes both freshwater and marine species that may visit estuaries occasionally.
Occasional visitors to the estuary can be either marine or freshwater species that enter the estuary for a short period of time. Other fish species may use estuaries on a seasonal basis, and this use can be classified as either facultative or obligate. Facultative fish use estuaries only if they are available, if not they find alternative habitats. This includes species like yellow-eye mullet ( Aldrichetta forsteri ), which can enter estuaries as juveniles but can also complete their life cycle in the marine environment. Obligate fish need to use estuaries to complete their life cycle. In the Surry estuary this includes species such as the short-finned eel ( Anguilla australis ) and the common galaxid ( Galaxias maculatus ). Other fish species, such as black bream ( Acanthopagrus butcheri ) are considered to be permanently estuarine as they can complete their entire life cycle within the estuary. More information on how fish use estuaries can be found in Appendix G.
Many of the organisms that inhabit estuaries, or even use estuaries for part of their life cycles, have adapted and in some cases rely on the hydrodynamic cycle of estuaries (Figure 3). One example of this is black bream ( Acanthopagrus butcheri ), which have been shown to spawn in estuaries as the salt wedge advances back up the estuary following a river mouth opening (Sherwood and Backhouse 1982; Newton 1996). Another example is the common galaxias ( Galaxias maculatus ). Common galaxias typically migrate from the freshwater reaches of rivers to estuaries, where they spawn in vegetation at the spring tide. The eggs adhere to the vegetation and hatch when inundated at the next spring tide (EEMSS 2006).
Fish and their habitat utilisation in the Surry estuary have been investigated between June 2004 and June 2005 as part of a PhD study on the Surry estuary. Results from the study have shown that fish species in the Surry estuary make significant use of flooded habitats, and that flooded habitats are as important as the main channel of the estuary. The study has also shown that species composition changes with river mouth state (open or closed), and that this has a bigger influence on usage of habitats than seasons (Becker 2007).
2.2.3 What are the current threats to fish in the Surry estuary? Fish health and diversity can be impacted on by a number of factors. These threats need to be minimised to ensure that indigenous fish health and diversity remains high. Key threats to fish diversity, health and abundance include: • artificial river mouth openings and draining of wetlands • poor water quality • reduced water quantity • loss of habitat • pathogens and parasites
Overfishing may also pose a threat to the health of fish populations. Bag and size limits are in place to ensure that fishing does not irreparably reduce the breeding population to below viable levels. Due to the enforcement of bag and size limits conducted by Fisheries Victoria, the risk of overfishing is considered to be low.
2.2.4 What is the current condition of fish in the estuary? Fish populations in the Surry estuary have in the past been negatively impacted by estuary entrance management. The Surry estuary has a history of fish kills linked to artificial river mouth opening; with the last major fish kill occurring after an illegal opening in 2005 with an estimated 30,000 fish of a range of species killed. Recovery from such an event can take a considerable amount of time, and it is more than likely that the larger longer lived species like black bream will take a number of years to recover.
2.2.5 What information is needed to improve management? There is currently a reasonable understanding of the fish species and their usage of the Surry estuary. However there are some information gaps that, while not essential, would improve the understanding of fish in the Surry estuary. These information gaps include improving the understanding of links between fish species and estuarine habitats.
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2.2.6 What is the capacity to change fish in the estuary? Effective protection and enhancement of fish populations in the Surry estuary requires a number of different management approaches. It is essential to not only protect the fish populations, but to identify and protect key habitats essential for different life history stages. Managing any uses of fish populations, either commercial or recreational, is also important and should be done in accordance with the principles of ecologically sustainable development. Monitoring and evaluation of fish populations are vital to ensure that management is proactive and adaptive, rather than solely reacting to problems.
2.2.7 Management actions – fish Fish Management objective: Demonstrated recovery of fish stocks from the fish kill in 2005 and previous events.
Management action target : An increase in the population size and number of year classes of black bream from those recorded in 2005. Action No. Action Key Lead Priority Implementation Agency Tool SF1 Identify key fish habitat areas within the estuary and SP GHCMA VH develop management actions to protect and improve these areas whilst considering economic, social and cultural values as well as environmental. SF2 Establish an ongoing monitoring program to collect MER DPI VH information on angler visitor numbers to the Surry estuary over time. SF3 Develop/identify indicators of condition for indigenous SP, MER GHCMA VH fish diversity for use in monitoring progress towards achieving the resource condition target for fish. SF4 Undertake literature review of the habitat and SP DPI VH environmental conditions required to sustain the production (spawning, recruitment, survival, growth and movement) of black bream. SF5 Implement the actions relevant to the Surry estuary from SP DPI VH the Glenelg Hopkins Fishery Management Plan SF6 Commence a fish tagging program for recreationally SP, CE, MER FISHCARE H important species involving community groups.
2.3 Water quality 2.3.1 The importance of good water quality Good water quality is essential for a healthy ecosystem. Fish and other organisms require good levels of dissolved oxygen (generally above 5mg/L) for survival, while aquatic plants require good levels of light.
2.3.2 Water quality in the Surry estuary The Surry River Restoration Plan (SKM 2000) highlighted the lack of information on water quality in the estuary and recommended establishing a monitoring program to address this information need. In light of this recommendation, water quality within the Surry estuary has been monitored at a number of sites on a monthly basis since October 2003. Water quality parameters and monitoring sites are presented in Appendix H.
2.3.3 What are the current threats to water quality in the Surry estuary? There are a number of factors that can influence estuarine water quality. Key threats to water quality include: • artificial river mouth openings • high levels of nutrients • erosion and sedimentation
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• reduced freshwater inflow
2.3.4 What is the current condition of water quality in the Surry estuary? There are currently three key water quality issues in the Surry estuary: • Nutrients, eutrophication and algal blooms • Deoxygenation • E.coli
Nutrients Although the water quality monitoring (Appendix H) shows that nutrient inputs into the Surry estuary are lower than other regional estuaries, there are still indications that nutrients may be a potential problem within the estuary. One of the key indicators of nutrient problems is algal blooms. Nitrogen and phosphorus are essential to plant growth, however excessive levels can contribute to the eutrophication of a waterway. Eutrophication can lead to algal blooms, which may have a serious impact on water quality. Algal blooms, particularly non-toxic blue-green algae, have been recorded at different times over the past few years within the Surry estuary. Non-toxic algal blooms are still a concern as they limit recreational access to the waterway, increase oxygen demand and decrease light penetration. The increase in oxygen demand that may occur as a result of an algal bloom could be a potential factor in causing the complete deoxygenation of the water column noted in the upstream section of the estuary.
Nutrient inputs can either come from the surrounding catchment, or from sediment within the estuary. As highlighted above, nutrient inputs to the estuary appear to be low. However, samples are only taken at the Woolwash, and are only representative of a single point in time, which means peak periods of nutrient input that typically following heavy rainfalls may have been missed. Further investigation is required to determine the total nutrient input into the Surry estuary from catchment sources.
As estuaries are depositional environments, nutrient levels in the sediments may build up over many years. When the estuary becomes anoxic during low freshwater flow periods, the nutrients stored in the sediments can be released into the water, making it available for use by plants and other organisms. The amount of nutrients in the sediments of the Surry estuary and the potential rate of release under anoxic conditions were investigated in February and May 2007. The primary motivation for investigating the sediment nutrient release was to determine if it could possibly be driving the algal blooms in the Surry estuary and potentially contributing to the deoxygenation in the upstream area of the estuary.
Benthic chambers were deployed at two sites, one at the Boat Ramp and the other at Barnetts, for 18hrs in both February and May 2007. These chambers are designed to measure the rate of release of nutrients from the sediments and are essentially large containers that sit on the bottom and collects samples at fixed intervals.
Analysis of these samples shows that under anoxic conditions in February and May 2007, nitrogen, phosphorus and silica were being released from the sediment. The amount of nutrients is comparable to many other estuarine environments that suffer from blue-green algal blooms (Nicholson and Longmore 2007). In fact, the benthic chamber installed at the dissolved oxygen probe at Barnetts was estimated to release enough phosphorus into the water column in 10 days to support Figure 7 – Benthic chamber being retrieved an algal bloom (Nicholson and Longmore 2007). High phosphorus from the Surry estuary in February 2007 levels are ideal for blue-green algae, as unlike other algae species, they are able to fix nitrogen out of the air (Nicholson and Longmore 2007).
Favourable conditions for an algal bloom include low flow, calm conditions, available nutrients and warm water temperatures - conditions that typically occur over summer in the Surry estuary. Options for reducing the amount of nutrients in the sediments are limited, the primary conclusion of the benthic chamber deployments is that the “only way to remediate the eutrophic condition of the Surry estuary is to increase river flows into the estuary (Nicholson and Longmore 2007).” However, investigations into possible ways to minimise the release of nutrients from the sediment need to take place, considering that anoxic conditions in estuaries are natural conditions during low flow periods. 18 Surry Estuary Management Plan
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Deoxygenation Dissolved oxygen is necessary for aquatic life to survive, with fish requiring a minimum concentration of 5mg/L. Typically in estuaries in southwest Victoria, oxygen at the base of the estuary can be gradually used up through normal biological activity. However over summer and autumn in the upper reaches of the Surry estuary, this layer of deoxygenated or anoxic water has been found to extend all the way to the surface and can extend over a one-kilometre stretch of the upper estuary.
In 2005, the presence of the deoxygenated water was one of the primary reasons for refusing to authorise artificially opening the estuary entrance due to the risk of causing a fish kill through the movement of this slug of water through the estuary. This is precisely what occurred following the illegal opening of the estuary on the 11 th July 2005, and resulting in a mass fish kill and conditions remaining poor throughout the entire estuary for a number of days.
Initially it was thought that the charophyte algae that form dense mats in the upstream section of the estuary (see Section 2.1) might be contributing to the poor water quality conditions through die-off and decomposition. However, as the species is perennial, it is unlikely that it is contributing to the decrease in dissolved oxygen levels that have been noted in the upstream section of the estuary over the past few years. In fact, it is possible that the plant is contributing positively to dissolved oxygen levels, through photosynthesis.
A number of investigations have been undertaken to further investigate the causes of the low dissolved oxygen in the estuary’s upper reaches. Preliminary investigations indicate that the deoxygenation is linked to nutrient dynamics and cycling within the estuary. Although the nutrients in the waters entering the estuary are low, it is possible that there has been a build-up of nutrients in the sediment over a long period of time. These nutrients can be released from the sediments and thereby create ideal conditions for algal blooms. As these blooms eventually die off, there is a possibility that they are using up all of the oxygen.
Using mechanical means to improve the dissolved oxygen levels has been put forward as one possible solution. Increasing oxygen levels can be achieved through either oxygenation or aeration. Aeration is a strategy that has been used in other estuaries, for example the Swan Canning system in Western Australia (Hamilton, Chan et al. 2001). The primary purpose of aeration in the Swan Canning estuary was to attempt to control eutrophication. However it was not found to be overly effective (Hamilton, Chan et al. 2001).
Evaluation of the feasibility of aeration to improve oxygen conditions in the Surry estuary was undertaken by a consulting firm at the request of Glenelg Hopkins CMA (GHD 2007). The report found that although aeration may help improve oxygen concentrations, it is unlikely that it would help over the short term and was likely to be cost prohibitive. Initial costs provided as part of the report indicate that aeration of the estuary, as a short-term management option, would cost in excess of $26,000 (GHD 2007). The use of aeration as a long-term management option is likely to require in excess of $550,000 to cover capital costs (GHD 2007), while the costs of operating over 25 years would exceed $300,000.
E.coli Escherichia coli ( E.coli ) is a bacterium found in the gut of warm-blooded animals, including humans and livestock, and indicates faecal contamination, and can cause gastroenteritis, stomach cramps, and diarrhoea. EPA guidelines for primary contact of E.coli are less than 200 organisms per 100mL of water. Potential sources of E.coli may include stock access and leaking septic systems.
E.coli is monitored on a monthly basis at two sites in the Surry estuary. Monitoring to allow an assessment of E.coli against EPA guidelines requires five samples to be undertaken over a 30 day period. Assessment of E.coli in the Surry estuary during winter has just been completed, with one sample taken every week for five weeks. The median level of E.coli over this period was 1050 organisms per 100mL. This indicates that levels in the Surry estuary exceed the guideline criteria for both primary (200 organisms per 100mL) and secondary contact (1000 organisms per 100mL).
When interpreting the results it is important to consider the dates and weather conditions when this sampling took place. Sampling in weeks 3 and 4, the 4 th and 11 th July 2007 respectively, were taken following the first significant rainfall in winter, which resulted in a rapid increase in streamflow, with freshwater flows to the estuary the highest recorded for three
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2. KEY MANAGEMENT AREAS years. It is possible that the lack of rainfall over the past few years had resulted in a build up of faecal matter in the catchment, all of which washed into the estuary.
The current E.coli sampling provides insight into winter levels of E.coli within the Surry estuary; however further sampling is required over the summer period. Should further sampling highlight issues with E.coli then targeted sampling to detect sources is advisable.
2.3.5 What information is needed to improve management? In order to maintain good water quality, the State Environment Protection Policy (Waters of Victoria) sets out environmental water quality objectives. These water quality objectives recommend a range of values between which water quality can be assumed to be healthy. If water quality within the estuary falls outside of these values, then actions should be undertaken to facilitate improvements. Some water quality parameters, such as turbidity, well defined objectives have not been developed due to a lack of data. At present, guidelines are prepared at a statewide level, with no consideration for variation across the state. Estuary specific guidelines would allow variation within individual estuaries to be properly accounted for as well as inform a process for refining the state wide SEPP (WoV) guidelines for estuaries. Both SEPP (WoV) and the ANZECC Guidelines (2000) outline the processes required for establishing site-specific water quality guidelines.
As highlighted above, further detailed information on the catchment sources of nutrients would also help improve management.
2.3.6 What is the capacity to change water quality in the Surry estuary? Although there are water quality problems in the Surry estuary, the capacity for addressing some of these issues may be limited, primarily due to the high capital costs and the limited environmental benefit. There is a need for more information on some aspects to further improve the management of water quality, particularly the identification of catchment sources of nutrients.
Continuation of monitoring is vital to understand the complex relationships between the state of the river mouth, water quality and the ecology of the system. Furthermore, it is essential for determining seasonal trends and variations and establishing risks associated with eutrophication, stratification and potentially reduced volumes of freshwater inflow. A long-term data set is also essential in establishing estuary specific water quality guidelines.
Water quality Management objective : Achieve a standard of water quality that protects the diversity and abundance of aquatic ecosystems and allows recreational and aesthetic enjoyment of the estuary.
Management action target : Develop and apply water quality criteria specific to the Surry estuary using the ANZECC Guidelines (2000). Action No. Action Key Lead Priority Implementation Agency Tool SWQ1 Continue monitoring water quality on a minimum monthly MER GHCMA VH basis. SWQ2 Conduct a monitoring program for both E.coli and MER GHCMA VH Enterococci during summer to enable assessment of levels against EPA criteria. SWQ3 If levels of E.coli or Enterococci are found to exceed EPA MER GHCMA H guidelines implement a targeted monitoring program to identify sources. SWQ4 If required, implement remedial actions to reduce E.coli OW GHCMA M and Enterococci inputs into the Surry estuary. SWQ5 Apply the principles and methods described in chapter 3 MER GHCMA M
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of the ANZECC Guidelines (2000), using data from the current water quality monitoring program to develop and adopt acceptable water quality criteria for the Surry estuary. SWQ6 Implement an estuary water quality evaluation and MER GHCMA M reporting process in order to monitor attainment of the resource condition target.
2.4 Hydrology (water quantity) 2.4.1 The importance of hydrology Water quantity is important in the functioning of estuaries and can also influence water quality. Freshwater inflow plays an important role in the movement of the salt wedge; the duration of stratification and the process of seasonal closure of the estuary entrance (see Figure 3 and Figure 4).
Water quantity, in terms of inundation, is also an important natural process in estuaries. High winter flows within the estuary are essential for effective flushing of the system and maintenance of the environmental, social and economic values of the estuary. Flushing is necessary to remove all traces of stratification from the system and allow the process of salt wedge formation and stratification to begin again. Flushing acts as a “reset” button for water quality conditions within the estuary. This is essential as a major spawning cue of recreationally important fish species such as black bream and may also be important in the life cycles of many other estuarine species.
2.4.2 Hydrology in the Surry estuary The amount of freshwater inflow into estuaries is linked to rainfall, extraction and land use. Assessment of both the sustainable diversion limits (SDL) and flow stress ranking (FSR) of the Surry River indicate that the impact of extraction and diversion in the winterfill period (June to October) is negligible. The FSR indicates that there is some impact on summer flows. Future increases in extraction and diversion in the Surry catchment could result in a decrease in freshwater inflow to the estuary, which may influence water quality and exacerbate existing issues with mouth openings.
The volume of water that is held within the estuary varies depending on water level height. At 1.5m AHD the volume of the estuary is approximately 380ML. Understanding how much water is held in the estuary at a given time is important as it gives some indication of how much flow is needed to replace the water in the estuary – of key importance if water quality is a concern. To illustrate this, if the mouth is open and the water height is 1.5m AHD and the freshwater inflow to the estuary is 380ML/day, the water within the estuary is replaced every 24hrs.
Freshwater inflow is particularly important when attempting to manage the poor water quality conditions within the estuary. The fish kill that occurred in 2005 was exacerbated by both the deoxygenated water and the low freshwater inflows, which ensured that water quality conditions in the estuary remained poor for a number of days. In 2005, freshwater inflow was just 4.2ML/day, which meant it took a long time for water within the estuary to be completely replaced – 90.5 days at this flow rate. . An increase in freshwater flows to only 20ML/day would decrease the amount of time required to completely replace the water in the estuary to less than 19 days. The quicker a slug of deoxygenated water is moved through the estuary, the better as it reduces the amount of damage that can be done to biota.
2.4.3 What are the threats to hydrology? Potential threats to the hydrology (water quantity) of the estuary include: • climate change • water extraction and diversion • land use change
2.4.4 What is the current condition of flows in the Surry estuary? Freshwater inflows into the Surry estuary over the past few years have been amongst the lowest recorded. In fact the maximum daily flow recorded in 2006 is the lowest since records began at the Woolwash gauging station in 1975 (Appendix J). The maximum flow rate recorded in 2007 was significantly higher at around 2,900ML/day.
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The trend in average annual freshwater inflows to the estuary shows a gradual decrease over the thirty year period between 1976 and 2006 (Figure 8), however there is significant variability between years.
Average annual flow for the Surry estuary between 1976 and 2006
220 210 200 190 180 170 160 150 140 130 120 110 100 90 80 70
Average flow (ML/day) Average 60 50 40 30 20 10 0 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 Year
Figure 8 – Average annual flow for Woolwash gauging station for the period between 1976 and 2006, showing both the moving average and the linear trend lines.
2.4.5 What information is needed to improve management? One factor that has not been investigated is the relationship between streamflow and groundwater. It is important to understand the impacts that groundwater extraction may have on the base flows in the Surry River.
2.4.6 What is the capacity to change hydrology in the Surry estuary? Opportunities for influencing freshwater inflows into the estuary are very limited. However, it is important that any new proposals for extraction from the Surry estuary be carefully considered.
Hydrology Management objective : Achieve a standard of water quantity that protects the diversity and abundance of aquatic ecosystems and allows recreational and aesthetic enjoyment of the estuary.
Management action target : Develop and apply water quality criteria specific to the Surry estuary using the ANZECC Guidelines (2000). Action No. Action Key Lead Priority Implementation Agency Tool SWQ7 Investigate the impacts of groundwater extraction on MER GHCMA VH baseflow to the Surry estuary
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2.5 Estuary entrance management and artificial river mouth opening 2.5.1 Importance of estuary entrance management Seasonal closure is a natural process in south west Victoria, and indeed in other parts of the world (e.g Potter, Beckley et al. 1990; Whitfield 1999). However the closure of the estuary entrance can impact a number of social and economic values of the surrounding area, and estuary entrances can be artificially opened to relieve the pressure of inundation on these values. Artificially opening the mouth is not without environmental consequences. One of the more visible impacts of the environmental impacts is fish kills, which have been known to occur in the Surry estuary. Other impacts may include the flushing of fish eggs and larvae to sea. Careful management of the estuary and its entrance is required to minimise the impacts on all estuary values.
2.5.2 Estuary entrance management and artificial river mouth opening in the Surry estuary Estuary entrance management, particularly artificial river mouth opening, is regulated under the following legislation: • Section 67 of the Water Act 1989 , administered by the Glenelg Hopkins CMA through Works on Waterways permits; • Section 37 of the Coastal Management Act 1995 administered by the Department of Sustainability and Environment through consents.
These are discussed in more detail in Appendix K.
2.5.3 What are the threats and risks of estuary entrance management and artificial river mouth opening? The decision to open or not open an estuary is complex, with a range of factors that need to be taken into consideration, including water quality and inflow, as well as environmental, social and economic values. When making a decision about artificial river mouth openings, the cost to the environment and the benefits of a healthy system to all has to be weighed against the cost of flooding private property and infrastructure.
Table 3 shows some of the potential impacts of either opening or not opening on a number of environmental, social and economic values. As can be seen from the table, trade offs need to be made when making a decision to open or not open. When considering opening or not opening an estuary entrance, it is important that the cost of either decision is considered against the benefit of the action.
To ensure that all management decisions follow a consistent approach and consider all values, the Estuary Entrance Management Support System (EEMSS) has been developed. Much of the ecological information required to populate EEMSS has already been collected such as water quality, bird, fish and vegetation data. Collection of data on the social and environmental values at different water levels and times of the year will commence in early 2008 and will be incorporated into EEMSS to ensure they are taken into equal consideration in decisions regarding river mouth openings.
There are always arguments for and against opening the Surry estuary mouth depending on which assets people value most highly. The challenge is to balance the likely impacts on each asset and make an objective decision based on risk. To illustrate this, Table 3 highlights some of the impacts of opening or not opening the estuary mouth at any given time on the various asset groups. It is important to note that the level of impact and therefore risk is not fixed and will vary with water level and time of year.
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Figure 9 Factors that need to be considered to reduce the risk of a fish kill following an artificial river mouth opening (EEMSS 2006)
Table 3 – Some of the assets of the Surry estuary and the potential impacts of opening or not opening the estuary entrance
Impacts Asset group Asset Opening Not opening Recreational If an opening is done under the wrong Inundation of the boat ramp. fishing conditions, then there is the possibility of a fish Social kill. This will impact on future fishing opportunities. Swimming Make sure that warning signs are in place None while the opening is being conducted. Boating None Inundation of the jetty and boat ramp. Bird watching Openings generally result in a large drop in Inundation of wetlands can create additional water levels. This may cause birds to move to habitat, which can be extremely valuable other areas. refuge in drought conditions.
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Impacts Asset group Asset Opening Not opening Exercise/dog None Possible inundation of walking tracks. walking Economic Agriculture None Inundation of pasture Tourism Potential for negative publicity about the area Impact of inundation on the access and if there is a fish kill functioning of the Narrawong Caravan Park. Commercial If an opening is done under the wrong Migration of eels and galaxids may be affected fishing conditions, then there is the possibility of a fish if prolonged. kill. This will impact on current and future fishing opportunities and result in economic loss. Environmental Physical Can lead to the drainage of wetlands, Can over time lead to the degradation of habitat reduction in the amount of available habitat for vegetation. The period of inundation before fish and birds. degradation occurs depends on the species. Fish Potential for a fish kill, egg and/or larvae loss Migratory species and marine visitors unable to sea, possible strandings of juvenile fish. to get in or out during their peak migration periods. Birds Reduces the water level and results in the loss Increases the extent of open water and of habitat for waterbirds margin dwellers- provides a range of water levels in the vegetated and raptors. Opening increases the inundated areas that can be used for foraging, available mudflats for margin dwellers – non- nesting and roosting. vegetated. Water quality If done under the wrong conditions, opening None can lead to the drainage of oxygenated water from the estuary, which can lead to a fish kill. Water None None quantity
2.5.4 What is the current condition of estuary entrance management and artificial river mouth opening in the Surry estuary? Although the decision regarding artificial river mouth opening needs to be made based on prevailing conditions, it is also important to consider and learn from past river mouth openings. Looking at how the estuary has responded to river mouth openings under various conditions in the past, it can provide insight into the likely consequences of opening the estuary under current conditions. Records from the past few years show that there have been a number of mass fish kills in the Surry estuary associated with mouth openings (Table 4). Mass fish kills have only been recorded following artificial river mouth openings. Although there have been minor fish deaths following natural openings, nothing of the magnitude that occurred following the 2005 artificial opening has been reported. It is important to note that although there haven’t been mass fish kills following natural openings, it is possible for them to occur.
Table 4 – Records of fish kills resulting from mouth openings in the Surry estuary
Date Opening type Mass fish Flow rate Data source (natural/artificial) kill? (ML/day) (y/n) 1980s – at least 2 A Y unknown C. Cooper pers. comm. significant fish kills 1991 – April A Y 2.34 ∗ C. Cooper pers. comm. 1993 - May A Y 1.797 ∗ C. Cooper pers. comm. 1995 – June A Y 18.293 ∗ C. Cooper pers. comm.
∗ Flow rates for these months are the monthly average
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1997 – 29 th June A Y 4.214 Portland Observer page one – 2/7/1997 1999 – 19 th June A Y 7.143 Portland Observer page one – 23/6/1999 2005 – 11 th July A Y 4.2 GHCMA, Portland Observer page 1
Comparing records of known openings where there has been a fish kill (Table 4) with known openings where there have been no mass fish kills (Table 5); indicates that a high freshwater inflow is an important factor in reducing the risk of a fish kill when artificially opening the estuary mouth. This is not surprising due to the number of processes in estuaries that are related to freshwater inflow including stratification and mouth closure.
Table 5 – Flow rates and dates of known natural openings where there have been no recorded mass fish kills
Date Flow rate (ML/day) 1998 – 21 st June 19.5 2000 – June 26.8 2003 – 4 th July 27.6 2004 – 18 th June 91.7 2005 – 5 th August 18.9 2006 – 30 th July 13.2 2007 – 3 rd July 18.7
Authorisation to open the mouth of the Surry estuary was withheld in 2005, 2006 and 2007, due to conditions in the estuary unsuitable for an opening and the associated high risk of a mass fish kill. Water quality conditions in the upstream reach of the estuary have deteriorated during low flow periods, resulting in almost no oxygen throughout the water column at a number of the upstream sites. This area, stretching downstream from Wades Road Bridge, has been the primary reason for refusing permission for an artificial opening over the past three years. As a consequence of this, there has been inundation of economic and social assets and considerable angst within the community.
Case studies Mouth openings over the past three years have provided an interesting insight into the Surry estuary and the potential risks that may be associated with artificial river mouth openings. The following section provides more detail on river mouth openings in 2004, 2005, 2006 and 2007.
Case study one – 2004 Date of opening 18 June 2004 Type of opening Natural opening (natural/artificial) Flow rate (as measured 91.7 ML/day at the Woolwash) Mass fish kill (yes or no) No Post opening water Water quality tests done at three sites along the estuary on the 27 th June 2004 showed that the quality system was well mixed, well oxygenated and the water was completely fresh. Duration of opening Approximately six months. The mouth remained open for some time, closing in late December 2004 (Alistair Becker pers. comm. 2006).
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Case study two – 2005 Date of opening 11 July 2005, sometime between 5 and 7am Type of opening Artificial – unauthorised Flow rate (as measured 4.2 ML/day at the Woolwash) Mass fish kill (yes or no) Yes Pre opening water quality Dissolved oxygen (DO) conditions on the 5 th of July 2005 (see graph below) show that although there were a number of sites that had very low levels of DO, sites from the Princes Highway Bridge downstream had good quality water for the top metre. The graph below also shows that all the poor water quality sites were in the upper reaches of the estuary.
Dissolved oxygen profiles for the Surrey River Estuary, July 5th 2005.
Dissolved oxygen (mg/L) Site 1 - River M outh 0 12 34 5 67 8910 0 Site 2 - Boat Ramp
-1 Site 3 - Highway Bridge -2 Site 4 - M cIntyre House
-3 Site 5 - Bells Creek Confluence bottom(m) -4 Site 6 - Gasline Landing
Site 7 - Pear Tree Point Depth fromto surface -5
M inimum dissolved oxygen requirements for fish (5mg/L)
Post opening water The dissolved oxygen probe installed approximately one kilometre downstream of the oxygen quality depleted area, showed that following the opening it took between five and seven hours for the oxygen depleted water to travel one kilometre. This slug of poor water quality then had to travel a further three kilometres downstream to reach the estuary, which would have taken between 15 and 21 hours.
As fish were observed dying and in distress well before then, it is highly unlikely that conditions in the upstream reach of the estuary caused the initial fish kill. The water quality monitoring undertaken on the afternoon of the 11th of July supports this. The graph below shows that all of the sites in the estuary had dissolved oxygen levels less than the minimum 5mg/Lrequired for fish. It also shows that the depth of all sites has decreased by one metre, which means that the opening of the mouth has stripped off the top layer of water, removing all of the suitable habitat.
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Dissolved oxygen profiles for the Surry Estuary, July 11th 2005.
Dissolved oxygen (mg/L) Site 1 - River Mouth 0 1 2 3 4 5 6 7 8 910 0 Site 2 - Boat Ramp
-1 Site 3 - Highway Bridge Site 4 - McIntyre House -2 Site 5 - Bells Creek -3 Confluence
bottom (m) bottom Site 6 - Gasline Landing -4 Site 7 - Pear Tree Point Depth from surface to to surface from Depth -5 Minimum dissolved oxygen requirements for fish (5mg/L)
Duration of opening Seven days Comments The initial cause of the fish kill was opening of the estuary mouth when flow and water quality conditions were not suitable, resulting in a rapid drop in water level, and the top layer of oxygenated water being flushed out to sea. The deoxygenated water in the upstream reach exacerbated conditions, as there were limited freshwater flows this water took a considerable amount of time to move through the system. Although tidal inputs can improve water quality conditions, no tidal inputs were noted until the 15th of July. Conditions did not improve substantially until the 18th of July 2005 at which point the mouth had closed again due to lack of flow
The mouth reopened naturally on the 5 August 2005.
The impacts on fish populations were significant. Estimated mortalities were in the range of 20,000 to 30,000, although mortalities could have been greater due to difficulties in accessing all areas of the estuary. A survey conducted three weeks after the opening recorded only 58 fish representing just five species throughout the entire estuary (Grixti, McKeown et al. 2006). A follow-up survey at the end of September 2005 found only 57 fish in the entire estuary.
The otoliths, or ear bones, of a number of black bream were extracted to allow the age of each fish to be determined. Otoliths function much the same as tree rings, in that the number of growth rings can be counted and the age of the fish determined. The aging was conducted by PIRVic who found that there was an unusual lack of older fish (Grixti, McKeown et al. 2006), which may be an indication of previous mortalities (Grixti, McKeown et al. 2006). Only one fish in the sample was older than five years (Grixti, McKeown et al. 2006).
Case study three – July 2006 Date of opening 30 July 2006 Type of opening Natural Flow rate as measured at 13.2 ML/day the Woolwash Mass fish kill (yes or no) No Pre opening water quality Poor water quality conditions similar to those recorded in 2005 were present. Post opening water quality Duration of opening 20 days. The estuary closed on the 19 August 2006 and then reopened naturally on the 24 August 2006. Comments The primary difference between 2005 and 2006 is the recorded freshwater inflows at the Woolwash. Freshwater inflows in 2006 were three times higher than those recorded in 2005. As the freshwater inflow was the primary difference between 2005 and 2006, it potentially illustrates the importance
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considering freshwater flows when making decisions about artificial river mouth openings.
Case study four – July 2007 Date of opening 3rd July 2007 Type of opening Natural Flow rate as measured at 18.7 ML/day the Woolwash Mass fish kill (yes or no) No Pre opening water quality Poor water quality conditions similar to those recorded in 2005 and 2006 were present. Post opening water Dissolved oxygen profiles for the Surry estuary 4 June 2007 quality
D.O. (mg/L). 0 1 2 3 4 5 6 7 8 0
-0.5
E1 -1 E2
-1.5 E3
Depth (m). Depth E4 -2 E6
-2.5 E9 E11
-3 Min DO requirements for fish
Duration of opening Still open as at the 27 November 2007 Comments Although there was some debate about the possibility of this opening being illegal, it is highly likely that the opening was natural. Heights of the sandbar at the estuary entrance were recorded on a weekly basis and had remained steady, ranging between 1.5 and 1.55m AHD along the length of the sandbar. Water level heights in the estuary in the early hours of the 3 rd of July exceeded the height of the sandbar, indicating that the mouth was likely to have opened naturally.
The graph below shows the change in water level over time between midnight on the 2 nd of July to midday on the 4 th of July. The small increase in water level that occurred on the afternoon of the 3 rd of July is due to the tide.
1.8 Water level 1.6 1.4 Sandbar height 1.2 1 0.8 0.6 0.4 Height Height (m AHD) 0.2 0 00:00_02/06/2007 03:00_02/06/2007 06:00_02/06/2007 09:00_02/06/2007 12:00_02/06/2007 15:00_02/06/2007 18:00_02/06/2007 21:00_02/06/2007 00:00_03/06/2007 03:00_03/06/2007 06:00_03/06/2007 09:00_03/06/2007 12:00_03/06/2007 15:00_03/06/2007 18:00_03/06/2007 21:00_03/06/2007 00:00_04/06/2007 03:00_04/06/2007 06:00_04/06/2007 09:00_04/06/2007 12:00_04/06/2007 Time and date
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2.5.5 What information is needed to improve management of the estuary entrance? From observations of artificial and natural mouth openings over the past few years, a good understanding of the consequences of ill timed mouth openings has been developed.
One of the major information gaps has recently been addressed. The Surry estuary flood study project has compiled maps showing what areas of land are inundated at what water level heights. This information is integral to ensuring that new infrastructure is appropriately sighted and designed, and will also aid in modifying existing infrastructure, like Caravan Park Road.
2.5.6 What is the capacity to influence estuary entrance management in the Surry estuary? The Estuary Entrance Management Support System (EEMSS) is the primary tool for estuary entrance management, and represents the best approach to improving management of artificial river mouth openings. Water quality issues in the upstream section of the estuary will influence the ability to open the estuary; however there is limited capacity to address these issues in the short term due to the high costs associated with any mechanical means.
2.5.7 Management actions – estuary entrance and artificial river mouth opening Estuary entrance and artificial river mouth opening Management objective : Implement a management process for the estuary entrance that provides the best possible compromise between the ecological requirements of the estuary and the social and economic requirements of the local community.
Management action target : Establish a protocol for estuary mouth opening using the estuary entrance decision support system. Action No. Action Key Lead Priority Implementation Agency Tool SARMO1 Apply the Estuary Entrance Management Support SP GHCMA VH System to produce revised artificial river mouth opening protocols that fully consider the risks to social, economic and environmental values. SARMO2 Replace the existing septic system at the Narrawong OG DSE VH Caravan Park SARMO3 Raise Caravan Park Road to reduce the impact of OG Glenelg VH inundation Shire SARMO4 Continue investigating the causes of poor water quality in SP GHCMA VH the upstream zone of the estuary with the view to identifying mitigation options SARMO5 Incorporate flood study results into Glenelg Shire SP Glenelg VH planning overlays Shire SARMO6 Incorporate findings into management regime or GHCMA VH undertake works based on outcomes of investigations into poor water quality in the upstream zone of the estuary
2.6 Inundation 2.6.1 Why is inundation important? Inundation is a natural process and can play an important role in the life cycle of many species, for example black bream. Periodic inundation of wetlands is also necessary to ensure their ongoing health. However, inundation can negatively impact on social and economic uses of the estuary and surrounding area.
Inundation is a threat to social uses of the estuary, in particular recreational fishing and boating, for example it causes the boat ramp at the estuary to be submerged, restricting its usage. Inundation is strongly linked to the estuary entrance and
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2. KEY MANAGEMENT AREAS artificial river mouth openings (Section 2.5). At present, inundation is one of the main reasons for artificially opening the estuary mouth.
2.6.2 Inundation at the Surry estuary In 2007 a flood study was conducted at the Surry estuary. The main purpose of this study was to collect information on the extent of flooding both as a result of high river flows and also as a result of closure of the estuary mouth. Figure 10 shows the extent of inundation for a number of water levels ranging between 1m AHD and 2m AHD. It can be seen that the greatest area of inundation is in and around the mouth area. As can be seen from Figure 10, many of the wetland areas in the upstream section of the estuary do not become inundated until water levels reach 1.3m AHD.
When considering the area of inundation at specific water levels it is important to remember that estuary water level will be also be affected by predicted increases in sea level rise, which may also impact on the bar at the mouth of the estuary.
Figure 10 Flood extents at specified water levels during periods of mouth closure
2.6.3 What are the current issues related to inundation in the Surry estuary? The primary issues related to inundation at the Surry estuary are related to the inundation of private property close to the estuary entrance. Inundation of the facilities at the Narrawong Caravan Park and of Caravan Park Road is a threat; however there are projects currently underway to reduce these impacts.
2.6.4 What information is needed to improve management? Results from the flood study need to be integrated into the Glenelg Shire Planning Scheme to ensure that inundation levels are considered in any future development.
2.6.5 What is the capacity to influence inundation in the Surry estuary? Options for manipulating water levels within the estuary were investigated by a consultant at the request of Glenelg Hopkins CMA (GHD 2007). Potential options evaluated included pumping, syphoning, construction of a regulator at the estuary entrance, pipe through the dunes, and investigating methods of opening the entrance that do not result in a rapid
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2. KEY MANAGEMENT AREAS decrease in water level. Permanent modification of the estuary entrance through construction of a regulator or similar structure are not appropriate, as they are in direct contradiction with the management principle set out in Section 1.4.
Pumping was trialled at the Surry estuary in 2006 and was found to be costly and of limited benefit, only lowering the water level three centimetres over a 36hr period. This was an expensive exercise, costing in excess of $20,000, without including staff time.
The use of a syphon to remove deoxygenated water from the estuary, like pumping, may require a discharge license from the EPA to allow the poor quality water from the estuary to be discharged to sea. This option would also require extensive monitoring to ensure that the syphon is removing water only from the lower layer. The outlet of the syphon would need to be maintained to ensure that it does not become blocked with sand. Similar to syphoning, a pipe system to draw water from the upper layer of the estuary was also investigated. The only main difference between this option and syphoning is that water would be drawn from the upper layer, which may lead to a reduction in the amount of good quality water available and is therefore highly unfavourable.
It is also possible that different methods of opening the estuary mouth could be trialled. Currently when the mouth is opened artificially a drop in water levels of over one metre are recorded. If the drop in water level exceeds the depth of the oxygenated layer it is possible for a fish kill to occur. Other methods of opening other than excavating a channel through the sand bar might be as efficient but drop the water level more slowly, decreasing the risk of a fish kill. A “dry notch” has been proposed for use in estuaries in New South Wales, however the purpose there was to destabilise the sand bar at the estuary entrance to encourage a full opening. The dry notch concept was trialled at the nearby Fitzroy estuary, and was found to slowly decrease the estuary water levels. Following the trial at the Fitzroy, a proposal for a more rigorous trial was put forward, requiring: • Appropriate earthmoving machinery on site for up to 72 hrs with an operator available 24hrs a day over this period. • Staff on site 24 hrs per day to monitor the notch and to direct the machinery operator as required. • Accurate survey of the notch excavated to document its dimensions and establish a benchmark for potential future use of the method and to enable calculations of flow rate. • 12 hourly monitoring of water quality conditions within the estuary as water level declines. • Close monitoring of water level decline (perhaps every three hrs) to document rate of water level drop Detailed monitoring of any trial undertaken at the Surry estuary would be required to ensure that a full opening did not occur and that there were no adverse impacts of the trial, which would significantly add to the cost, set out in Table 6. Based on the dot points outlined above, a closely monitored trial would cost in excess of $8,000.
Table 6 provides a summary of what the long-term (25year) costs of installation and operation may be of any of the investigated engineering options.
Table 6 Engineering options for management of inundation at the Surry estuary, including capital costs and net present value. Net present value factors in the cost of ongoing operation over the next 25 years and is essentially what it costs in today’s money. Net present value includes the capital costs (taken from GHD 2007).
Option Capital cost Net present value Pumping $600,000 $910,000 Syphon $540,000 $690,000 Piping $570,000 $710,000 Dry notch $1550 $86,414
Relocating low-lying assets or modifying infrastructure to increase resilience to inundation may reduce risk to economic assets such as the Narrawong Caravan Park. Upgrade and replacement of the existing septic system with treatment plants not only ensures that septic function is not impacted by estuary water levels, but reduces potential impacts on water quality and public safety within the estuary. Other potential infrastructure modifications include raising Caravan Park Road and extending the boat ramp. Before any structures are modified or relocated, it is important to fully consider the results of the Surry Flood Study (Figure 10), which provides key information on areas of inundation at a range of water level heights.
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2.7 Pest plants and animals 2.7.1 What is the importance of controlling pest plants and animals? Pest plants and animals are either introduced species (e.g. rabbits) or native species outside of their natural range (e.g. Cootamundra wattle). Control of pest plants and animals are important as they can outcompete native plants and animals and compromise natural values.
2.7.2 Pest plants and animals at the Surry estuary
Pest plants There are two key pest plant species within the management plan area that threaten the environmental, social and economic values of the Surry estuary. The more serious of the two is divided sedge, which not only out-competes native vegetation in wetlands, but also vigorously competes with pasture species. The other species is sea spurge, which has the potential to negatively affect environmental values. Both species are discussed in more detail below.
Divided sedge Divided sedge ( Carex divisa ) was introduced into Australia from Europe, and can occur around the edges of marsh habitat. Transportation methods are unknown, but could include livestock, machinery, hay, water and wind. Divided sedge effectively out-competes native vegetation, smothers salt marsh habitat and is extremely difficult to remove once established (Sinclair and Sutter 2007). It also aggressively competes with low-lying pasture.
Estuarine habitat mapping (section 2.1) included mapping of divided sedge infestations at the Surry estuary. A total of 4.7 hectares of divided sedge infestation was mapped and is included on the map of current ecological vegetation classes presented in Appendix D. These infestations need to be monitored carefully and actions developed to eradicate or control divided sedge.
Sea spurge Sea spurge ( Euphorbia paralias ) was introduced into Australia from the Mediterranean, possibly through ballast water. The plant is a small leafy shrub that displaces native species in dune systems. It also can alter the morphology of dunes. It has the potential to negatively effect species such as Hooded Plover that prefer open sand areas for nesting. Stems and leaves of sea spurge contain a toxic substance that is released when the plant is damaged or broken. This can cause skin irritations and potentially eye damage. Sea spurge is not listed under the Catchment and Land Protection Act 1994 and therefore is not a priority species for control via State government funding. Sea spurge can be found in the area around the mouth of the estuary. Figure 11 – Sea spurge ( Euphorbia paralias) near the mouth of the Surry estuary Potentially threatening pest plants Spartina Spartina was introduced into Australia in the late 1920s. There are two species of Spartina in Australia. One species, S.townsendii is sterile, reproducing through rhizome expansion . S.anglica produces fertile seed, which can be transported through currents, wading birds and human activities.
Spartina threatens native vegetation in estuarine wetlands through the trapping of sediments and subsequent alteration of habitat structure and characteristics. This affects native fauna, especially waterbirds, aquatic invertebrates and fish. It also has the potential to take over seagrass flats, which could impact on a variety of fauna species, including juvenile black bream and juvenile estuary perch. This species has not been recorded within the management plan area. The nearest recorded location is in the Barwon estuary near Geelong.
The introduction of Spartina, otherwise known as rice or cord grass, is listed as a threatening process under Schedule 3 of the Flora and Fauna Guarantee Act 1988 (SAC 1996). The species is also declared as an aquatic pest plant species under the Fisheries Act 1995 .
Surry Estuary Management Plan 33
2. KEY MANAGEMENT AREAS
Typha There are three species of typha, also known as bulrush or cumbungi, which occur in Victoria, two of which are native. It is not known which of the three species occurs within the management plan area. Waterways with high nutrients and low flows present ideal habitat for all three species of typha.
In some areas typha is considered a problem plant as it can restrict flow and increase sedimentation. However, typha also provides important environmental functions in providing habitat and food for birds and other animals. It can also play an important role in filtering water and may also provide a role in protecting stream banks from erosion.
Pest animals Rabbits Rabbits ( Oryctolagus cuniculus ) are the most serious vertebrate pests in Victoria, with an estimated annual economic impact in the Glenelg Hopkins region alone of about $38 million (Glenelg Hopkins CMA 2002). This is due to their impact on agricultural production through direct competition with livestock for grasses. Rabbits also contribute significantly to erosion due to their burrowing and overgrazing which can contribute to high sediment loads within the estuary and lead to detrimental habitat change.
Rabbits are also detrimental to the native flora and fauna of the estuary area, being identified under the Flora and Fauna Guarantee Act 1988 as a threat to the survival and range of a number of species. In addition, they are considered a major contributor to the declining quality of vegetation surrounding wetlands. Reduction in biomass and biodiversity of native vegetation through grazing by rabbits is listed under the Flora and Fauna Guarantee Act 1988 as a threatening process.
Foxes Foxes ( Vulpes vulpes ) are another serious threat to biota in the estuary area, both economically and environmentally. Economically, they are a threat to livestock predating lambs and, to a lesser extent, calves. Foxes may be responsible for the death of 30% of all newborn lambs. Environmentally, they are a threat to waterbirds and other native species. Species such as the Hooded Plover ( Thinorinis rubricollis ), listed under the Flora and Fauna Guarantee Act 1988 and considered threatened in Victoria, are at great risk from foxes as they nest on the ground. Foxes also prey on native mammals, although the extent to which this is happening in the area is unknown. Predation of native wildlife by foxes is listed under the Flora and Fauna Guarantee Act 1988 and Schedule 3 of the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 as a threatening process.
2.7.3 What is the capacity to influence the distribution of pest plants and animals? Prevention of the introduction of pest plants and animals is the ideal strategy. However where this is not achieved; early detection and rapid control is essential to allow for containment and possible eradication of any detected pest plants and animals. The estuarine habitat mapping (Section 2.1) gives a baseline of one pest plant; regular habitat monitoring might be expanded to include pest plants, which would enable an assessment of the effectiveness of control strategies.
2.7.4 Management actions – pest plants and animals Pest plants and animals Management objective : Reduction in the extent of listed weed species.
Management action target : Establish a baseline understanding of listed weed species. Action No. Action Key Lead Priority Implementation Agency Tool SPPA1 Conduct a risk assessment for invasive plant species as SP DPI M per the Glenelg Hopkins Draft Weed Plan? SPPA2 Removal of willows within the catchment, particularly OG GHCMA M around the Woolwash area.
34 Surry Estuary Management Plan
2. KEY MANAGEMENT AREAS
SPPA3 Undertake a feasibility study for the eradication of SP and OW DPI M Divided Sedge from the estuary and undertake appropriate management actions depending on the outcomes of a feasibility study.
2.8 Response to emerging issues – fish pathogens and parasites 2.8.1 Why is response to emerging issues important? Many pathogens and parasites occur in waterways. Outbreaks of pathogens and parasites in fish may be an indicator of stress, and in particular poor water quality. . Stress causes fish to lose the protective film from their skin that acts as a barrier to disease and infection. As fish become stressed they are less able to protect themselves against pathogens and parasites
Current management of pathogens and parasites focuses on response and control of outbreaks, rather than prevention. EPA has produced a Waterway Incident (Fish Death) Response Guideline that outlines the methods for collecting infected specimens and reporting on the fish kill, along with relevant contact details. Investigation into any potential stressors that may have made fish or other aquatic fauna more susceptible to pathogens and parasites also needs to be conducted.
2.8.2 Fish pathogens and parasites in the Surry estuary Although to date there have been no reported occurrences of pathogens or parasites in the Surry estuary, there have been instances of poor fish health recorded in other estuaries in the south west. In September 2004 a small number of Black Bream caught in the Yambuk Lake estuary and wetlands had ulcers and lesions under the scales. Black Bream of all sizes and weights were affected; however no other species were affected. The pathology report on the Black Bream revealed ulcerative dermatitis and myositis of the skin, which is consistent with Epizootic Ulcerative Syndrome, otherwise known as EUS or Red Spot Disease. Testing of infected samples collected from Yambuk Lake proved inconclusive; the exact cause of these lesions is unknown.
2.8.3 Management actions – pathogens and parasites Pathogens and parasites Management objective : Maintain healthy indigenous fish populations.
Management action target : Maintain current agency endorsed response plans for all reported incidents of pathogens and parasites. Action No. Action Key Lead Priority Implementation Agency Tool SPP1 Ensure any fish kills are reported, cleaned up, monitored MER EPA VH and assessed according to the EPA Waterway Incident (Fish Death) Response Guidelines
Surry Estuary Management Plan 35 4. LOCAL GOVERNMENT PLANNING 3. External factors that will influence management of the Surry estuary There are a number of key external factors that will influence the management of the Surry estuary and the assets that have been identified. Estuary values, be they environmental, social or economic, are not static and may change with time. However there are a number of factors that may have a significant impact on these values and cause changes greater than would otherwise normally be expected. The most obvious of these are climate and land use change, which are likely to irreversibly alter the estuarine environment. This section discusses these two factors in more detail.
3.1 Climate change and sea level rise 3.1.1 Why is this issue? Climate change and sea level rise has the potential to have serious impacts on the habitat values of the Surry estuary. Latest research results put the rate at which sea level rise is occurring at between 0.8 and 8 centimetres every ten years (Department of Sustainability and Environment 2004).
Sea level rise is not a recent occurrence, CSIRO (2003) states that in the last 100 years sea level has risen between 10 and 20 cm. A number of factors are likely to contribute to an increase in sea level globally, which includes the melting of glaciers and the thermal expansion of seawater as a result of increased temperatures due to climate change. Sea level is predicted to rise between 0.09 and 0.88m by 2100, which equates to a rise of 0.8 to 8.0 mm per year (CSIRO 2002; Department of Sustainability and Environment 2004)
3.1.2 What are the implications for the Surry estuary? Prediction of the impacts of climate change is extremely difficult, as any impacts are likely to be highly complex and dependant on future actions and emission levels. In general, it is thought that climate change in southwest Victoria will result in higher average temperatures, decreased rainfall, more frequent storm events and increased storm ferocity (CSIRO 2002).
The implications of climate change for estuarine habitat and associated biodiversity values may be significant. As estuary water level increases, many of the fringing vegetation communities will, where possible, move landwards. If the opportunity for responding to increases in water level is not available, then there is a very real risk of some vegetation communities and habitat types becoming locally extinct.
Other implications for the estuary could include: • Alteration of wave energy, which could have a dramatic effect on the estuary entrance and its management, along with changes in species distributions and life cycles (Howden, Hughes et al. 2003). • An increase in shoreline erosion (Pittock 2003), • Dieback of reeds and other plants due to increased salinity resulting from increased estuarine area, which would also have effects on the aquatic animals (Pittock 2003),
Species with longer generational times are likely to be more seriously affected by climate change as they not able to quickly adapt to an altered environment. Other general impacts on the area may include an increase in temperature, a decrease in rainfall and an increase in storm events and ferocity.
The effect of an increase in water level height on the state, size or location of the sand bar at the estuary mouth is unknown, and would require a detailed study of the geomorphology and hydrodynamics of the estuary mouth area. It is possible however that the sand bar could decrease in size if there was an increase in water level within the system which would subsequently lead to the estuary being opened to the sea more frequently. If temperatures in the region continue to increase as predicted (CSIRO 2001) it is possible that the effects of higher evaporation and lower rainfalls may negate this. This makes it extremely difficult to predict what effects an increase in sea level may have on the opening/closing regime the estuary.
3.1.3 What can be done? Investment in estuarine habitat mapping and flood studies represent a responsible and pro-active response to this threat. The map and condition data produced from these exercises will enable habitat zones under threat from rising water levels
36 Surry Estuary Management Plan 4. LOCAL GOVERNMENT PLANNING to be accurately located and prioritised for the application of measures to facilitate retreat of vegetation communities as water level rises.
Measures that could allow for vegetation community retreat might include: • Fencing of retreat zones combined with vegetation enhancement plantings and controlled grazing. • An ecosystem stewardship scheme for private landholders willing to change adjacent land use practices for the benefit of the ecosystem. • Strategic purchase, covenanting and resale of covenanted land freehold land. • Strategic purchase and reversion of freehold land to Crown land
3.1.4 Management actions – climate change and sea level rise Climate change and sea level rise Management objective : Incorporate new information on climate change as it comes to light into the management framework for the Surry estuary.
Management action target : Action No. Action Key Lead Priority Implementation Agency Tool SCC1 Review and update this management plan on a regular SP GHCMA VH basis
3.2 Land use change 3.2.1 Why is this issue? Land use can influence the amount of water entering rivers. The Water and Land Use Change study (WatLUC 2005) was commissioned to investigate the impact of different land use scenarios on stream flow in rivers in southwest Victoria and southeast South Australia.
For the Surry estuary catchment (P2), Table 7 shows that there is expected to be a decrease in some land use types such as broadacre agriculture, however there is likely to be an increase in the amount of land used for dairying over the next 20 years.
The predicted impacts of these land use changes on stream flow in the Surry estuary are shown in Figure 12. It can be seen that under a number of different scenarios, land use change over the next 20 years is likely to result in a decrease in flow ranging from 5.5% to 8.5%. It is important to note that none of the projections produced by the Water and Land Use Change study incorporate climate change predictions.
Changes in land use and the subsequent impact on stream flow are likely to have an impact on the water quality of the Surry estuary (See Section 3.5).
Surry Estuary Management Plan 37 4. LOCAL GOVERNMENT PLANNING Table 7 - Projected changes in land use for the Surry River catchment (P2)
2370001-P2 1990 2003 2010 2020 2030
0.0% 0.0% 0.0% 0.1% 0.1% agriculture: crop agriculture: broadacre 34.2% 24.3% 22.4% 20.3% 18.2% agriculture: dairy 9.5% 17.9% 18.7% 20.1% 21.5% horticulture: vegetables 0.0% 0.0% 0.0% 0.0% 0.0% horticulture: trees 0.0% 0.0% 0.0% 0.0% 0.0% horticulture: grape vines 0.0% 0.0% 0.1% 0.1% 0.1% native vegetation 49.9% 49.9% 49.9% 49.9% 50.0%
forestry: hardwood (blue gum plantation) 0.0% 0.9% 1.6% 1.7% 1.7%
forestry: sugar gum or other low rainfall farm forestry species 0.0% 0.0% 0.0% 0.0% 0.0%
forestry: softwood (pine) 2.0% 2.1% 2.2% 2.3% 2.4%
rural residential land use 0.5% 0.9% 1.1% 1.4% 1.7%
urban residential land uses 0.3% 0.3% 0.3% 0.4% 0.4%
commercial land uses 0.6% 0.6% 0.7% 0.7% 0.8% transport 3.0% 3.0% 3.0% 3.1% 3.1%
0%
-1%
-2%
-3% Scenario One- BASE CASE
Scenario Two- HIGH CROP -4% Scenario Three- HIGH FORESTRY
-5% Scenario Four- HIGH GRAPE
Scenario Five- HIGH DAIRY -6% Scenario Six- HISTORICAL TRENDS
Scenario Seven- IUCN -7%
CHANGE IN STREAMFLOW (% of annual streamflow) streamflow) annual of (% STREAMFLOW IN CHANGE Scenario Eight - HIGH NATIVE VEGETATION
-8% Scenario Nine - RURAL RESIDENTIAL
Scenario Ten - BROADACRE GRAZING -9% 1985 1990 1995 2000 2005 2010 2015 2020 2025 2030 DATE
Figure 12 - Projected decrease in stream flow for the Surry River sub catchment (P2) based on different land use change scenarios
38 Surry Estuary Management Plan 4. LOCAL GOVERNMENT PLANNING 4. Local Government Planning 4.1 The Planning Scheme The Glenelg Shire Planning Scheme contains State and local planning policies, zones and overlays and controls land use and development within the municipality. The scheme indicates if a planning permit is required to change the use of land, to construct a building or make other changes to the land (Department of Sustainability and Environment 2001). The Municipal Strategic Statement focuses on key land use planning and development issues relating to primary production, urban development, infrastructure provision and the environment and is to be reviewed on a three yearly basis.
4.2 Local planning policy Decisions regarding applications for planning permits are made using planning policies (Department of Sustainability and Environment 2001). An appropriate local planning policy is required for the area covered by this management plan to ensure control of potential changes in land use and increasing pressure from recreational activities. Future reviews of the Glenelg Shire Planning Scheme represent important opportunities to ensure planning policy forms a strong foundation for the maintenance and enhancement of the significant environmental, economic, social and cultural values of the area.
4.3 Zones and overlays Zones The planning scheme zones land for particular uses – e.g. residential, industrial, business or other. The scheme lists the zones along with particular requirements and information, such as if a planning permit is required and the matters the council must consider before deciding to grant a permit. The zones also contain information relative to land uses, subdivision of land, construction of new buildings and other land changes (Department of Sustainability and Environment 2001).
Zones covering the Surry estuary and adjacent land include a Public Purposes and Recreation Zone (PPRZ), a Farming Zone (FZ), a Rural Living Zone (RLZ), a Rural Conservation Zone (RCZ2) as well as a Township Zone (TZ) which covers the Narrawong township.
Overlays Overlays are maps showing special features of land that need to be considered in planning decisions. There are a number of overlays in the management plan area including two Environmental Significance Overlays (ESO1 and ESO2) and two Development Plan Overlays (DPO5 and DPO7).
Different overlays have different objectives. ESO1 covers the coastal zone within the management plan area and has two objectives: • Ensure the long -term protection of coastal and marine ecosystems. • Prevent inappropriate development in coastal areas that is likely to prejudice the long-term environmental values of the coast. ESO2 covers the Surry estuary and has three environmental objectives. These are: • Maintain environmental diversity and quality of areas that constitute wetlands, swamplands, intertidal areas, lagoons and significant waterways. • Prevent inappropriate development adjacent to significant wetlands and waterways. • Prevent pollution of significant waterways and wetlands and the degradation of habitat areas.
Development Plan Overlay 5 (DPO5) covers land surrounding the township of Narrawong, while DPO7 covers land along the coastal strip between Portland and Narrawong. The purpose of a Development Plan Overlay is to require any development in the area covered by that overlay to prepare a plan outlining the form and conditions of use and address the specific criteria in the appropriate schedules. Schedules to the overlays, which can be found online at www.dse.vic.gov.au/planningschemes , state the information that needs to be included in any development plan. The conditions set out in DPO7 require that any development plan take into account factors such as coastline recession, sea level rise and storm surge. Results from the Surry estuary flood study will provide valuable information on the likely impacts of sea level rise on the estuarine area, while other studies currently underway in the state will provide valuable information on the possible impacts of coastline recession.
Surry Estuary Management Plan 39 4. LOCAL GOVERNMENT PLANNING 4.4 Landscape values Landscape values are important socially, recreationally and economically - for tourists and local residents. While this plan recognises the importance of landscape values, no specific direction is recommended by the management plan regarding management of this issue. Appropriate zones and overlays applied by local government represent the primary management tool to prevent development and uses that are not aesthetically pleasing in areas with important vistas.
4.5 ‘Sea change’ development Lifestyle aspirations and the lure of coastal environments drive the ‘sea change’ phenomena, bringing associated expectations with respect to local (public and private) services. Turn over in housing stock and new land development tends to follow, again with consequences for the adequacy of local infrastructure, planning controls and township character.
It is important to consider the impacts of climate change particularly sea level rise, storm surge and coastline recession and the impacts that this will have on the landscape over the next few decades. Development Plan Overlay 7 (DPO7) provides the framework whereby these impacts can be considered when considering permit applications. Current studies underway both in the management plan area and across the state will provide important information to ensure that the best possible information is considered in the permit process.
4.6 Management actions – local government planning Local government planning Management objective : Direct and control development to protect the values of the Surry estuary and continue economic development within the framework of ecological sustainability.
Management action target : The results of the Surry estuary flood study incorporated into the Glenelg Shire Planning Scheme. Action No. Action Key Lead Priority Implementation Agency Tool SLGP1 Incorporate the results of the Surry estuary flood study SP GHCMA H into the Glenelg Shire Planning Scheme.
40 Surry Estuary Management Plan
5. MONITORING, EVALUATION AND REPORTING
5. Assessing the effectiveness of this management plan – monitoring, evaluation and reporting
The mechanism for assessment of the effectiveness of investment in the implementation of this management plan has two main components.
1. Short term assessment process This is to be achieved through evaluation of progress towards the implementation of Management Action Targets. This assessment will take place on an annual basis through a forum convened by the Glenelg Hopkins CMA in partnership with the Western Coastal Board (see section 1.7 for details). This process forms a component of the reporting requirement for the implementation of the South West Estuaries Coastal Action Plan.
2. Long term assessment process This is to be achieved through the evaluation of progress towards the implementation of resource condition targets (RTCs). At present, resource condition targets for the Surry estuary are being developed for the Glenelg Hopkins CMA Region. In general, decades represent realistic timeframes for meaningful assessment of progress towards RCTs. The effectiveness of this long term assessment process will rely heavily on the level of investment in establishing baseline condition and extent of key components of estuary health, and then long term monitoring to ensure that the condition of the estuary does not deteriorate from the established baseline condition.
The annual review process outlined in Section 1.7 represents a key mechanism for ensuring that the implementation, including the monitoring evaluation and reporting, of this management plan remains effective and relevant.
Monitoring Management actions identified in this plan, focus on protecting and enhancing the environmental, social and economic values of the Surry River Estuary. Effectiveness of investment in implementing these actions will be assessed through monitoring of the condition of key resources (components) of the estuary that define its overall health. The condition of these key resources will form the focus of RCTs.
Resource condition targets are the desired physical state (condition and or extent) of particular natural resource assets at a point in time in the future. In general, RCTs establish the long term target for investment in implementation of the management plan. As resource condition targets have yet to be finalised for estuarine environments, they have not yet been included in the management plan. The action tables identify management objectives, which are defined as the desired future state of the estuary. Management action targets (MATs), also included in the same tables, represent a first step towards achieving the resource condition target.
In order to ensure that progress is made towards achieving the MATs, and consequently the management objective, it is necessary to monitor implementation of not only the actions identified in this management plan but also the current condition of the estuary. Information on changes, both positive and negative, in the current condition gives managers a base on which to adapt management actions to respond to the changes in the estuary’s condition.
Monitoring is vital to ensuring that we are protecting and enhancing the environmental assets of the estuary. Monitoring programs are also useful in quantifying the progress of implementation, and form part of both short and long term assessment processes. Current monitoring programs include the estuarine water quality monitoring program, which monitors eight sites within the Surry estuary and two sites above the estuary. This program provides information on the water quality conditions within the estuary on a monthly basis. The advantage of the program is the provision of valuable baseline information, which ensures that managers have current information on the quality of water within the estuary. Future changes in water quality will be compared to the baseline data.
The estuary water quality monitoring program is currently being evaluated to assess how it can be expanded to ensure that it continues to meet all of the objectives.
Surry Estuary Management Plan 41
5. MONITORING, EVALUATION AND REPORTING
Evaluation Evaluation of the implementation of the management plan is a key component of adaptive management. To ensure that management actions are effective it is necessary to critically evaluate the outcomes from actions and understand the contribution that they make to the health of the estuary. In addition, it is necessary to evaluate the adequacy of monitoring programs to ensure the data collected is sufficiently robust to detect change at the desired level and to assess whether management objectives are being achieved. .
Reporting Reporting of the outcomes of current actions will take place as part of the annual meeting to review the implementation of the plan. Informing the wider community of the outcomes of the meeting will also represent an integral component of reporting. Reporting will need to identify the actions that have been implemented in the past 12 months, outcomes of those actions as well as identify any new issues or priorities within the management plan area.
Management actions – Monitoring, evaluation and reporting Monitoring, evaluation and reporting Management objective : Monitor and evaluate the health and functioning of the estuary and implementation of the estuary management plan.
Management action target : Undertake an evaluation of the implementation of the plan. Action No. Action Key Lead Priority Implementation Agency Tool SMER1 Review and evaluate the success of implementation of MER GHCMA VH actions from this plan on a yearly basis. SMER2 Develop realistic and measurable resource condition SP GHCMA H targets for the estuarine resources of the Surry estuary. SMER3 Report on the outcomes of this plan to the Coastal and MER GHCMA H Marine Technical Working Group on an annual basis. SMER4 Review all monitoring programs being carried out in the MER GHCMA H estuary plan area to ensure they are adequate for data requirements and meeting monitoring objectives. SMER5 Review and update this management plan in five years MER GHCMA H (2013) SMER6 Following development of estuarine RCTs for the Surry SP GHCMA M estuary, develop a monitoring program, including a series of indicators, to measure progress towards achieving the desired resource condition targets.
42 Surry Estuary Management Plan
REFERENCES
References
Allen, G. R., S. H. Midgley and M. Allen (2002). Field Guide to the Freshwater Fishes of Australia . Perth, Western Australian Museum.
Ball, D. and S. Blake (2007). Submerged aquatic vegetation in estuaries of the Glenelg Hopkins Catchment. DRAFT Report., Department of Primary Industries, Victoria, Queenscliff.
Barton, J. and J. Sherwood (2004). Estuary Opening Management in Western Victoria: An information analysis. Parks Victoria Technical Series . Melbourne, Parks Victoria.
Becker, A. (2007). Fish use of flooded margins of an intermittently open estuary. School of Life and Environmental Sciences . Warrnambool, Deakin University.
Costanza, R., R. d'Arge, R. de Groot, S. Farber, M. Grasso, B. Hannon, K. Limburg, S. Naeem, R. V. O'Neil, J. Paruelo, R. G. Raskin, P. Sutton and M. van den Belt (1997). The value of the world's ecosystem services and natural capital. Nature . 387: 253-260.
CSIRO (2001). Climate Change Projections for Australia. Melbourne, CSIRO Atmospheric Research.
CSIRO (2002). Climate Change And Australia's Coastal Communities, CSIRO Atmospheric Research.
CSIRO (2003). Greenhouse: questions and answers, CSIRO Atmospheric Research.
Day, J. H. (1980). "What is an estuary?" South African Journal of Science 76 : 198.
Department of Sustainability and Environment (2001). Planning: A Short Guide, Department of Sustainability and Environment.
Department of Sustainability and Environment (2004). Adapting to Climate Change - Enhancing Victoria's Climate Change - A consultation paper, Department of Sustainability and Environment.
Department of Sustainability and Environment (2005). Index of Stream Condition: The second benchmark of Victorian river condition. Melbourne, Department of Sustainability and Environment.
Duruz, R., Ed. (unknown date). The Long Walk by G.E. Morrison - Diary of his journey from Queenscliffe to Adelaide in 1879-80 .
EEMSS (2006). Estuary Entrance Management Support System (EEMSS) , Report prepared for GHCMA (project manager) Hamilton, Vic, Australia (118pp incl CD).
GHD (2007). Assessment of possible engineering options for water level control. Report to Glenelg Hopkins CMA .
Glenelg Hopkins CMA (2002). Glenelg-Hopkins Catchment Nutrient Management Plan - A framework for reducing nutrient loads and the increasing occurrence of algal blooms in regional waters, Glenelg Hopkins CMA, Hamilton, Victoria.
Glenelg Hopkins CMA (2002). Glenelg Hopkins Rabbit Action Plan - Strategic Rabbit Management. Prepared by Brett Harrison and South Pest Plants and Animals Team, Department of Natural Resources and Environment.
Glenelg Hopkins CMA (2002). Surry to the Sea. Project summary. Glenelg Hopkins CMA, Hamilton, Victoria.
Glenelg Hopkins CMA (2003). Glenelg Hopkins Regional Catchment Strategy 2003 - 2007, Glenelg Hopkins CMA.
Glenelg Hopkins CMA (2004). Glenelg Hopkins River Health Strategy 2004-2009, Glenelg Hopkins CMA, Hamilton.
Surry Estuary Management Plan 43
REFERENCES
Glenelg Shire Council (2002). Glenelg Shire Coastal Action Plan. Prepared by Parson Brinckerhoff Pty Ltd.
Glenelg Shire Council (2005). Glenelg Shire Strategic Tourism Plan 2005 - 2008 .
Grixti, D., D. McKeown and A. Morison (2006). Fish community abundance after a fish death event in the Surrey River, Victoria. Marine and Freshwater Systems Report No. 28 , Primary Industries Research Vcitoria, Queenscliff.
Hamilton, D. P., T. Chan, M. S. Robb, C. B. Pattiaratchi and M. Herzfeld (2001). "The hydrology of the upper Swan River Estuary with focus on an artificial destratification trial." Hydrological Processes 15 : 2465-2480.
Henry, G. W. and J. M. Lyle, Eds. (2003). The National Recreational and Indigenous Fishing Survey , Australian Government Department of Agriculture, Fisheries and Forestry, Canberra.
Howden, M., L. Hughes, M. Dunlop, I. Zethoven, D. Hilbert and C. Chilcot, Eds. (2003). Climate Change Impacts on Biodiversity in Australia, Outcomes of a workshop sponsored by the Biological Diversity Advisory Committee, 1-2 October 2002 , Commonwealth of Australia, Canberra.
Mondon, J., J. Sherwood and F. Chandler (2003). Western Victorian Estuaries Classification Project, Deakin University, Warrnambool.
Newton, G. M. (1996). "Estuarine icthyoplankton ecology in relation to hydrology and zooplankton dynamics in a salt-wedge estuary." Marine and Freshwater Research 47 (1): 99-111.
Nicholson, G. and A. Longmore (2007). Nutrient fluxes and trophic status of the Surry estuary during February and May 2007. Marine and Freshwater Systems Internal Report No. 89 , Primary Industries Research Victoria, Queenscliff.
NLWRA (2002). Australian Catchment, River and Estuary Assessment 2002 , Australian Government.
Pittock, B., Ed. (2003). Climate Change: An Australian Guide to the Science and Potential Impacts , Australian Greenhouse Office, Canberra.
Potter, I. C., L. E. Beckley, A. K. Whitfield and R. C. J. Lenanton (1990). "Comparisons between the roles played by estuaries in the life cycles of fishes in temperate Western Australia and Southern Africa." Environmental Biology of Fishes 28 : 143-178.
Price, P., S. Lovett and J. Lovett (2004). Managing riparian widths. Fact sheet 13., Land and Water Australia, Canberra.
Sherwood, J. and G. N. Backhouse (1982). Hydrodynamics of salt wedge estuaries: implications for successful spawning of black bream (Acanthopagrus butcheri), Faculty of Applied Science and Technology Research Warrnambool Institute of Advanced Education.
Sinclair, S. J. and G. Sutter (2007). Wetland vegetation mapping: interim report: Fitzroy and Surry Rivers. Report to the Glenelg Hopkins CMA , Arthur Rylah Institute.
SKM (2000). Surry River Restoration Plan. Final Report November 2000, Sinclair Knight Merz.
VCMC and DSE (2003). Ecosystem Services through Land Stewardship Practices: Issues and Options.
Victorian Coastal Council (2002). Victorian Coastal Strategy, Victorian Coastal Council, Melbourne.
WatLUC (2005). Water and Land Use Change study. Stage 2 Community Report., Water and Land Use Change Steering Committee and Sinclair Knight Merz.
Western Coastal Board (2002). South West Estuaries Coastal Action Plan, Coastal and Marine Planning Program, Western Coastal Board.
44 Surry Estuary Management Plan
REFERENCES
Western Coastal Board (2002). South West Victoria Regional Coastal Action Plan, Coastal and Marine Planning Program, Western Coastal Board.
Whitfield, A. K. (1999). "Ichthyofaunal assemblages in estuaries: A South African case study [Review]." Reviews in Fish Biology & Fisheries 9(2): 151-186.
Personal communications
Becker, Alistair (2006). Deakin University. Personal communication. 21 st August 2006. Cooper, C. (1999). Department of Primary Industries Victoria. Email to A. Mulhall (SKM). 13 th October 1999.
Surry Estuary Management Plan 45
GLOSSARY AND FURTHER INFORMATION
Glossary Actions - works or activities that need to be undertaken in order to achieve management objectives Algal bloom – A term used to describe the dense growth of planktonic algae which imparts a distinct colour to the water.
Artificial – man-made; not occurring naturally; made in imitation of something natural. Anoxic - containing no oxygen. Biomass – total weight, volume or energy equivalent of organisms in a given area. Dissolved oxygen – oxygen freely available in water for uptake by aquatic life and organic processes Dissolved oxygen levels in water need to be higher than 5 mg/L to be suitable for fish.
Eutrophication –is the excessive enrichment of a lake, etc. with nutrients, resulting in growth of organisms and depletion of oxygen.
EVC - Ecological Vegetation Class. Ecological vegetation classes provide a guide to the plant community and individual species that occur (or once occurred) in different parts of the landscape. Maps of the extent of EVCs prior to European settlement and the current extent have been produced by DSE.
Hydrodynamics - the movement of water. In estuaries it is also relates to the movement and changes in freshwater and saltwater.
Land managers - are the persons or agencies responsible for managing the land in the area. This includes land managers for both private and public land areas.
Life history stages – is the different stages that an individual goes through to reach adulthood. For fish these include egg, larvae, juvenile and adult. Different life history stages can have different environmental requirements. For example, eggs and larvae can be free floating in the water column, while a juvenile may be found in seagrass beds.
Morphology – the form and structure of the estuary. Natural – normal or to be expected; genuine or spontaneous; produced by nature; not created by human beings; not synthetic.
Objectives – these state the “preferred future” of the estuary that is how we would like the estuary to be in the future.
Photosynthesis – is the process by which plants use the sun’s energy and carbon dioxide for growth. Phytoplankton – plant plankton Plankton – usually small marine or freshwater plants (phytoplankton) and animals (zooplankton) drifting with the surrounding water
PPT – Parts per thousand. Usually the measurement of the salt content of water. Seawater has a salt concentration of 35ppt.
Public land managers –authorities, agencies or councils that have the responsibility for managing and maintaining public and Crown land areas and facilities.
Regionally controlled weeds - a category of weeds listed under the Catchment and Land Protection Act 1994 , and is those weed species that are considered to be widespread and considered important in a particular region.
Riparian – frequenting, growing on, or living on the banks of streams or rivers. Saltmarshes – wetland areas that are saline and subject to tidal influences, generally near the estuary mouth. SEPP WoV – State Environment Protection Policy (Waters of Victoria). This policy can be viewed on the Environment Protection Authority’s (EPA) website http://www.epa.vic.gov.au
Stakeholders – are those groups or individuals that have an interest, either economic, environmental, social or cultural, in the management plan area.
Stratification – occurs in estuaries due to the difference in densities between salt and freshwater. The end result is a layer of freshwater sitting on top of a saltwater layer.
46 Surry Estuary Management Plan
GLOSSARY AND FURTHER INFORMATION
Substrate – a surface on which an organism grows or is attached. Targets –how we would like the estuary to be at the end of this management plan, which is in 5 years time. Turbidity –a measurement of the cloudiness of water and is caused by having large amounts of sediment or foreign particles either suspended in the water column or stirred up by some activity. Sediment sources include erosion of land areas as well as erosion of the river’s banks.
Further information
AAV - Aboriginal Affairs Victoria – www.dvc.vic.gov.au/aav.htm CAMBA - China Australia Migratory Bird Agreement. – www.deh.gov.au/biodiversity/migratory/waterbirds DEH - Department of Environment and Heritage (Federal Government Department). – www.deh.gov.au DPI -Department of Primary Industries. – www.dpi.vic.gov.au DSE - Department of Sustainability and Environment. – www.dse.vic.gov.au DU - Deakin University. – www.deakin.edu.au EPA - Environment Protection Authority. – www.epa.vic.gov.au Glenelg Hopkins CMA - Glenelg Hopkins Catchment Management Authority – www.glenelg-hopkins.vic.gov.au GSC – Glenelg Shire Council – www.glenelg.vic.gov.au JAMBA - Japan Australia Migratory Bird Agreement - www.deh.gov.au/biodiversity/migratory/waterbirds LCC - Land Conservation Council – www.veac.vic.gov.au NHT – Natural Heritage Trust – www.nht.gov.au PV - Parks Victoria – www.parkweb.vic.gov.au SRW - Southern Rural Water – www.srw.com.au TFN - Trust for Nature – www.tfn.org.au VFF - Victorian Farmers Federation – www.vff.org.au WCB - Western Coastal Board – www.westerncoastalboard.vic.gov.au WCC – Warrnambool City Council – www.warrnambool.vic.gov.au
Surry Estuary Management Plan 47
APPENDICES
Appendices Appendix A –Notes from the workshop held on the 19 th July 2006 Glenelg Hopkins CMA – Surry estuary Workshop 19 July 2006 – Narrawong AGENDA Welcome and Update Overview of Workshop Estuary Uses, Threats and Values Vision for the estuary Next Steps and Close
USES – THREATS – VALUES What is important to you about the Surry estuary?
Participants were invited to select a photograph to help them tell a personal story about the estuary and to identify the uses, threats and values of the Surry estuary. These uses, threats and values were posted on the wall. They have been grouped according to similar comments. Estuary Uses & Activities Recreation • Nature to our children • Fishing • Enjoyment of birdlife etc • Swimming • Boating Amenity • • Dog walking Scenic panoramas • • Exercise Financial boost to village
Other comments Nature • Beach that people can’t get to • Wildlife • Inaction on previous plans/proposals – • Fish round robin of responsibilities – a mindset • Diversity of nature that the river is the problem • Natural breeding ground • Nature sanctuary
Threats Competing interests • Too many doing nothing • Greedy, selfish people • Incompetent management • River health and (versus?) community health Environmental impacts • Man over nature • Drought • Division of community – threat of decision • Pollution ( E. coli ) making being based on commercial • Lack of flow reasons • Sand bar too high • Estuary is home to, and used by, a large
number of wildlife species and their activities are under threat from our actions! Other comments • Uninformed, uneducated local input • Bureaucracy and management Load of rubbish • Inaction by stakeholders • Uncertain future • Bureaucratic road blocks • Glasshouse effect • Too many scientists who won’t make a • Legal action decision • CMA Values • Water activities 48 Surry Estuary Management Plan APPENDICES • Community • River ‘belongs’ to everyone • Values to wildlife not given enough • Valuable natural asset if well-managed consideration resource • Economic values over-riding environment – • Water however local economy will suffer • Birdlife, wetlands, fish, swimming, recreation, • Tourism – Economic - Property value: property values attract visitors to the area Enhancement if managed correctly • Tourism • To preserve for the future • Nature within the village
Discussion General discussion following this activity raised the following points: • Health of the river is important – disagreement on what is the best way to maintain that health • Revisiting material that’s already been done • What good is a Management Plan? • Cross-section of stakeholders need to be involved in any management planning process • There are too many government (and other) bodies involved! Who is responsible? • More complexity • Actions need to be consistent with Acts and laws • Benefit of all is important
VISION/PREFERRED FUTURE
Participants were invited to use a ‘story spine’ to describe their picture of a preferred future for the Surry estuary and surrounds. The following statements were gleaned from the stories they wrote and prioritized in the order below. This is not a ranking, but simply an indication of importance identified by the group at the workshop.
The actual stories that participants wrote are included in the appendix to this report.
Statements of a preferred future for the Surry estuary (vision) Access to the beach reserve, amenities etc. The river remains open so that the tidal movement keeps the river oxygenated rather than becoming stagnant! (39) Hopefully a healthy river left alone and problems of sewage and roads are fixed – we work around the river, not alter the river, and our children, grandchildren etc are able to enjoy a healthy river (31) The river makes us feel okay about the environment – the fish and the birds are telling us that there is a future (19) The river is healthy and this is in everyone’s best interest (13) Need a bit of middle ground – rather than extremes (12) Enjoying the day-to-day changes that nature has to offer (4) Bureaucracy has stuffed around and stuffed it all up (2) Continuous evaluation of the management plan: cyclic evaluation, planning and implementation (2) River being used – fishing, boating, canoeing, picnics and barbies (2) Everyone is happy (1) Narrawong has become the place to be!! (1) They appreciate nature more (1) No more CMA meetings (0) The Government spent so much money they opened the river 2 – 3 times a year before the level rose too high (0) Government bodies are still stuffing it up (0)
DISCUSSION AND NEXT STEPS • How do you overcome the problem of dividing the community? Important to recognize that we (the community) have a common problem and that there are different solutions • We need to lower the river level
Surry Estuary Management Plan 49 APPENDICES • We need some empathy and practical support – especially if our businesses/livelihoods are being affected by the river • The sewage problem at the caravan park needs to be fixed • We need more communication about what’s going on o Notices at the General store o Everyone sent information when it’s available o Explore some other communication options e.g. email and letterbox drops • We also need information on grants – what money is available to assist us? • We also want understandable information on the science and data underpinning the management decisions made on our behalf • We also want more specific data on the Surry itself – not generalised information on estuaries – we want facts • We want to hear and understand both sides of the argument
CMA agreed to do the following:
1. Put notices in the General Store to keep community up-to-date on the latest incident 2. Organise as a matter of urgency an information sessions to describe the science behind estuary management 3. Provide notes from this evening’s meeting (these notes) to everyone who attended and left contact details 4. Explore options for improving communication with the Narrawong community
50 Surry Estuary Management Plan APPENDICES Appendix B – Relevant legislation, policies and strategies
Regional South West Estuaries Coastal Action Plan Sets out how and what to consider when preparing individual estuary (2002) management plans. South West Victoria Regional Coastal Action Coastal Action Plans provide strategic coastal planning for the region. Plan (2002) Prepared by the Regional Coastal Board – Western Coastal Board. Provides more detail for the area than the Victorian Coastal Strategy Glenelg Shire Coastal Action Plan Provides more detail for the area than the Regional Coastal Action Plan and the Victorian Coastal Strategy Glenelg Hopkins Regional Catchment Strategy Prepared by the GHCMA and provides the primary planning framework 2003 – 2007 for land, water and biodiversity in the region Glenelg Hopkins Nutrient Management Plan Prepared by the GHCMA to provide a framework for nutrient (2002) management projects Glenelg Hopkins Draft Native Vegetation Plan Prepared by the GHCMA under the State framework for native (2003a) vegetation management. Glenelg Hopkins Weed Action Plan (2000a) Prepared by the GHCMA for the management of pest plants within the region Glenelg Hopkins Rabbit Action Plan (2000b) Prepared by the GHCMA for the management of rabbits within the region. Glenelg Hopkins River Health Strategy (2004) Prepared by the GHCMA and sets out strategies for ecological sustainability and the restoration of environmental condition in the region. Prepared under the Victorian River Health Strategy.
State Victorian Coastal Strategy (2002); Prepared under the Coastal Management Act 1995 to guide planning objectives on the Victorian Coast. The objectives are: • Sustain • Protect • Direct • Develop Victoria’s Biodiversity Strategy (1997); Forms a key step in the Flora and Fauna Guarantee Act, 1988 implementation program, shows how to achieve the Act’s objectives for conserving native species, communities and gene pools, preventing threats and encouraging community involvement. Victoria’s Native Vegetation Management – A The broad purpose of this framework is to achieve a net gain in extent Framework for Action (2002); and quality of native vegetation across the state. Coastal Management Act 1995 Provides for the co-ordinated and strategic planning of Victoria’s coastal resources • Established the Coastal Boards • Provides for the preparation of the Victorian Coastal Strategy and Coastal Action Plans • Requires consent for the use and development of Crown Land Crown Land (Reserves) Act 1978 Provides for the reservation of Crown Lands and the management of those lands Planning and Environment Act 1994 Established to provide a framework for planning the use, development and protection of land in Victoria. Water Act 1989 Provide for the integrated management of all elements of the terrestrial phase of the water cycle; and to promote the orderly, equitable and
Surry Estuary Management Plan 51 APPENDICES efficient use of water resources. Catchment and Land Protection Act 1994 Established the Catchment Management Authorities Flora and Fauna Guarantee Act 1988 The key piece of Victorian legislation for the conservation of threatened species and communities and for the management of potentially threatening processes Wildlife Act 1975 Provides for the protection and conservation of wildlife; and the prevention of taxa from becoming extinct. Aboriginal Heritage Act 2006 Provides for the protection of archaeological and aboriginal relics. Victorian River Health Strategy (2002) The VRHS provides the framework for regional communities to make decisions on river protection and restoration and to find the balance between using our rivers and maintaining their ecological condition. Fisheries Act 1995 Provides for the management and conservation of Victorian fisheries resources, habitats and ecosystems. Also aims to facilitate access to fisheries resources for commercial, recreational, traditional and non-consumptive uses. Environment Protection Act 1970 Purpose is to create a legislative framework for the protection of the environment in Victoria having regard to the principles of environment protection. Also establishes the Environment Protection Authority. Land Conservation (Vehicle Control) Act 1972 Controls vehicle traffic on public land to aid in the prevention of soil erosion and damage. This includes vast areas of the coastal zone.
Federal Environment Protection and Biodiversity Provides for the protection of the environment, especially those aspects Conservation Act 1999 of the environment that are matters of national environmental significance; and to promote ecologically sustainable development China Australia Migratory Bird Agreement Agreement between China and Australia for the protection of migratory (CAMBA) birds and their environment Japan Australia Migratory Bird Agreement Agreement between Japan and Australia for the protection of migratory (JAMBA) birds and their environment Aboriginal and Torres Strait Islander Heritage Provide for the preservation and protect places, areas and objects in Protection Act 1984 Australia and Australian waters that are places, areas or objects of particular significance to Aboriginals in accordance with Aboriginal tradition. Native Title Act 1993 Provides for the recognition and protection of native title and also establishes mechanism for determining claims to native title.
52 Surry Estuary Management Plan APPENDICES 1.1. Appendix C - Consultation framework for development and implementation of Estuary Management Plans
South West and Wimmera Recreational Cultural Heritage Program Business users Deakin GHCMA Landholders Cultural groups University
Sporting DSE DPI groups Environmental groups Western Coastal Board Local Government Other individuals and groups.
Including visitors to the Parks estuary area. Victoria
Identify: Provide technical and scientific • issues guidance. • management needs Identify: • opportunities for • issues implementation • management needs • opportunities for • opportunities for partnerships implementation • opportunities for partnerships
Estuary Management Plan
Estuary Entrance Management - Decision Support Framework (under development)
A risk management system for application to artificial river mouth opening processes.
CMTWG = Coast and Marine A scientific foundation for determination of artificial river Technical Working Group mouth opening protocols.
(Revised river mouth opening protocols will be added to the management plan once produced through this process)
Surry Estuary Management Plan 53 APPENDICES Appendix D – Ecological vegetation classes Pre 1750
54 Surry Estuary Management Plan APPENDICES Current EVCs
Surry Estuary Management Plan 55 APPENDICES Appendix E – Bird species recorded in the Surry estuary This list has been compiled from a variety of sources including personal observations and DSE surveys of the area.
Abbreviations VROTS – Victorian rare and threatened species NT – near threatened EN – endangered
FFG – Flora and Fauna Guarantee Act 1988 L – listed N – nominated for listing
EPBC – Environment Protection and Biodiversity Conservation Act 1999
CAMBA – China Australia Migratory Bird Agreement JAMBA - Japan Australia Migratory Bird Agreement
CAMBA/ Family name Common name Scientific name VROTS FFG EPBC JAMBA Anseranatidae Magpie goose Anseranas semipalmata NT L Anatidae Blue-billed Duck Oxyura australis EN L Anatidae Musk Duck Biziura lobata Anatidae Black Swan Cygnus atratus Anatidae Australian Shelduck Tadorna tadornoides Anatidae Australian Wood Duck Chenonetta jubata Anatidae Pacific Black Duck Anas superciliosa Anatidae Australasian Shoveler Anas rynchotis Anatidae Grey Teal Anas gracilis Anatidae Chestnut Teal Anas castanea Anatidae Pink-eared Duck Malacorynchus membranaceus Anatidae Hardhead Aythya australis VU L Podicipedidae Australasian Grebe Tachybaptus novaehollandiae Podicipedidae Hoary-headed Grebe Poliocephalus poliocephalus Podicipedidae Great-crested Grebe Podiceps cristatus Phalacrocoracidae Little Pied Cormorant Phalacrocorax melanoleucos Phalacrocoracidae Black-faced Cormorant Phalacrocorax fuscescens Phalacrocoracidae Pied Cormorant Phalacrocorax varius NT Phalacrocoracidae Little Black Cormorant Phalacrocorax sulcirostris Phalacrocoracidae Great Cormorant Phalacrocorax carbo Pelecanidae Australian Pelican Pelecanus conspicillatus Ardeidae White-faced Heron Egretta novaehollandiae Ardeidae Little Egret Egretta garzetta EN L Ardeidae White-necked Heron Ardea Pacifica Ardeidae Great Egret Ardea alba VU L C&J Ardeidae Intermediate Egret Ardea intermedia CE L Ardeidae Cattle Egret Ardea ibis C&J Ardeidae Nankeen Night Heron Nycticorax caledonicus NT Ardeidae Australasian Bittern Botaurus poiciloptilus EN L Threskiornithidae Glossy Ibis Plegadis falcinellus Threskiornithidae Australian White Ibis Threskiornis molucca Threskiornithidae Straw-necked Ibis Threskiornis spinicollis Threskiornithidae Sacred ibis Threskiornis aethiopicus Threskiornithidae Royal Spoonbill Platalea regia VU
56 Surry Estuary Management Plan APPENDICES Threskiornithidae Yellow-billed Spoonbill Platalea flavipes Acciptridae Black-shouldered Kite Elanus axillaris Acciptridae Whistling Kite Haliastur sphenurus Acciptridae Swamp Harrier Circus approximans Acciptridae Brown Goshawk Accipiter fasciatus Acciptridae Grey Goshawk Accipiter novaehollandiae VU L Acciptridae Collared Sparrowhawk Accipiter cirrhocephalus Acciptridae Wedge-tailed Eagle Aquila audax Falconidae Brown Falcon Falco berigora Falconidae Australian Hobby Falco longipennis Falconidae Peregrine Falcon Falco peregrinus Falconidae Nankeen Kestrel Falco cenchroides Rallidae Buff-banded Rail Gallirallus philippensis Rallidae Lewin's Rail Rallus pectoralis Rallidae Australian Spotted Crake Porzana fluminea Rallidae Spotless Crake Porzana tabuensis Rallidae Purple Swamphen Porphyrio porphyrio Rallidae Dusky Moorhen Gallinula tenebrosa Rallidae Black-tailed Native-hen Gallinula ventralis Rallidae Eurasian Coot Fulica atra Scolopacidae Latham's Snipe Gallinago hardwickii NT L Scolopacidae Common Greenshank Tringa nebularia Scolopacidae Common Sandpiper Actitis hypoleucos VU Scolopacidae Ruddy Turnstone Arenaria interpres Scolopacidae Sanderling Calidris alba NT Scolopacidae Red-necked Stint Calidris ruficollis Scolopacidae Sharp-tailed Sandpiper Calidris acuminata Haematopodidae Pied Oystercatcher Haematopus longirostris Recurvirostridae Black-winged Stilt Himantopus himantopus Recurvirostridae Banded Stilt Cladorynchus leucocephalus Charadriidae Red-capped Plover Charadrius ruficapillus Charadriidae Double-banded Plover Charadrius bicinctus Charadriidae Black-fronted Dotterel Elseyornis melanops Charadriidae Hooded Plover Thinornis rubricollis VU L Charadriidae Red-kneed Dotterel Erythrogonys cinctus Charadriidae Masked Lapwing Vanellus miles Laridae Pacific Gull Larus pacificus NT Laridae Kelp Gull Larus dominicanus Laridae Silver Gull Larus novaehollandiae Laridae Caspian Tern Sterna caspia NT C Laridae Crested Tern Sterna bergii Laridae Whiskered Tern Chlidonias hybridus NT Columbidae Common Bronzewing Phaps chalcoptera Cacatuidae Yellow-tailed Black Cockatoo Calyptorynchus funereus Cacatuidae Gang-gang Cockatoo Callocephalon fimbriatum Cacatuidae Galah Cacatua roseicapilla Cacatuidae Long-billed Corella Cacatua tenuirostris Cacatuidae Sulphur-crested Cockatoo Cacatua galerita Psittacidae Musk Lorikeet Glossopsitta concinna Psittacidae Purple-crowned Lorikeet Glossopsitta porphyrocephala Psittacidae Crimson Rosella Platycercus elegans Psittacidae Eastern Rosella Platycercus eximius Psittacidae Blue-winged Parrot Neophema chrysostoma Cuculidae Fan-tailed Cuckoo Cacomantis flabelliformis
Surry Estuary Management Plan 57 APPENDICES Cuculidae Horsfield's Bronze-Cuckoo Chrysococcyx basalis Cuculidae Shining Bronze-Cuckoo Chrysococcyx lucidas Strigidae Powerful Owl Ninox strenua VU L Strigidae Southern Boobook Ninox novaseelandiae Tytonidae Barn Owl Tyto alba Apodidae White-throated Needletail Hirundapus caudacutus Apodidae Fork-tailed Swift Apus pacificus Alcedinidae Azure Kingfisher Alcedo azurea Halcyonidae Laughing Kookaburra Dacelo novaeguineae Halcyonidae Sacred Kingfisher Todiramphus sanctus Climacteridae White-throated Treecreeper Cormobates leucophaeus Maluridae Superb Fairywren Malurus cyaneus Maluridae Southern Emu-wren Stipiturus malachurus Pardalotidae Spotted Pardalote Pardalotus punctatus Pardalotidae Striated Pardalote Pardalotus striatus Pardalotidae White-browed Scrubwren Sericornis frontalis Pardalotidae Striated Fieldwren Calamanthus fuliginosus Pardalotidae Brown Thornbill Acanthiza pusilla Pardalotidae Yellow-rumped Thornbill Acanthiza chrysorrhoa Pardalotidae Striated Thornbill Acanthiza lineata Meliphagidae Red Wattlebird Anthrochaera carunculata Meliphagidae Little Wattlebird Anthrochaera chrysoptera Meliphagidae Yellow-faced Honeyeater Lichenostomus chrysops Meliphagidae Singing Honeyeater Lichenostomus virescens Meliphagidae White-eared Honeyeater Lichenostomus leucotis Meliphagidae Brown-headed Honeyeater Melithreptus brevirostris Meliphagidae White-naped Honeyeater Melithreptus lunatus Meliphagidae New Holland Honeyeater Phylidonyris novaehollandiae Meliphagidae Eastern Spinebill Acanthorynchus tenuirostria Meliphagidae White-fronted Chat Epthianura albifrons Petroicidae Jacky Winter Microeca fascinans Petroicidae Flame Robin Petroica phoenicea Petroicidae Eastern Yellow Robin Eopsaltria australis Pachycephalidae Crested Shrike-tit Falcunculus frontatus Pachycephalidae Golden Whistler Pachycephala pectoralis Pachycephalidae Rufous Whistler Pachycephala rufiventris Pachycephalidae Grey Shrike-thrush Colluricincla harmonica Dicruridae Restless Flycatcher Myiagra inquieta Dicruridae Magpie-Lark Grallina cyanoleuca Dicruridae Grey Fantail Rhipidura fuliginosa Dicruridae Willie Wagtail Rhipidura leucophrys Campephagidae Black-faced Cuckoo-shrike Coracina novaehollandiae Artamidae Dusky Woodswallow Artamus cyanopterus Artamidae Australian Magpie Gymnorhina tibicen Artamidae Pied Currawong Strepera graculina Artamidae Grey Currawong Strepera versicolor Corvidae Forest Raven Corvus tasmanicus Corvidae Little Raven Corvus mellori Alaudidae Skylark Alauda arvensis Motacilidae Richard's Pipit Anthus novaeseelandiae Passeridae House Sparrow Passer domesticus Passeridae Red-browed Finch Neochmia temporalis Passeridae Diamond Firetail Stagonopleura guttata VU L Fringillidae European Greenfinch Carduelis chloris
58 Surry Estuary Management Plan APPENDICES Fringillidae European Goldfinch Carduelis carduelis Hirundinidae Welcome Swallow Hirundo neoxena Hirundinidae Tree Martin Hirundo nigricans Hirundinidae Fairy Martin Hirundo ariel Sylviidae Clamorous Reed-Warbler Acrocephalus stentoreus Sylviidae Little Grassbird Megalurus gramineus Sylviidae Rufous Songlark Cincloramphus mathewsi Sylviidae Brown Songlark Cincloramphus cruralis Sylviidae Golden-headed Cisticola Cisticola exilis Zosteropidae Silvereye Zosterops lateralis Muscicapidae Common Blackbird Turdus merula Sturnidae Common Starling Sturnus vulgarus
Appendix F – Surry River Restoration Plan Review The Surry River Restoration Plan was completed in 2000. Although this plan covered the entire catchment, it did contain actions relating the estuarine reach of the river. A review of the actions identified in the plan was undertaken before commencing this management plan, the results of which are presented below.
Implemented? Priority No. Action Comments (y/n)
Identify areas of significant conservation value No mapping of ecological vegetation classes has been 1 N (page 9) undertaken.
Establish a water quality monitoring and Water quality in the estuary has been monitored since November 2 Y assessment programme 2003 at a number of sites in the estuary.
90% of private estuary river frontage is now fenced. 75% of Prioritise sites for restoring riparian 3 private river frontage upstream of the estuary is also fenced. Y revegetation (page 12) 30,000 native plants have been planted.
Glenelg Shire Council is currently undertaking stage 2 of a heritage study for the Shire, which identifies possible sites for inclusion under the heritage overlay in the planning scheme. It is Identify heritage sites within the Surrey 4 hoped that identification of all potential sites within the shire N catchment (page 13) High would be complete in the middle to late part of this year before a formal amendment process to the planning scheme would be undertaken.
Establish beach access path on western side A pontoon has been set up to cross the river between the 5 Y of estuary (Page 14) caravan park and the reserve.
Review license conditions for breaching the Review of the conditions will take place following the 6 N bar at the river mouth development of EEMSS.
Review planning scheme and develop Glenelg Shire Council is currently undertaking a review of the 7 planning overlays in light of new information N planning scheme called the Glenelg Strategic Futures Plan. (page 17)
Encourage community involvement in Waterwatch is the currently the only community monitoring 8 monitoring and decision making (page 19 of Y program taking place at the estuary. Restoration Plan)
90% of private estuary river frontage is now fenced. 75% of Medium Undertake works to revegetate the Surry River 1 private river frontage upstream of the estuary is also fenced. Y riparian zone 30,000 locally native plants have been planted.
Surry Estuary Management Plan 59 APPENDICES
Implemented? Priority No. Action Comments (y/n)
Identify point sources of pollution in the Audit of dairy practises carried out by EPA. All dairies are 2 Y catchment (page 11) complying with EPA requirements.
Undertake works identified in the existing 3 N catchment management strategy (page 19)
90% of private estuary river frontage is now fenced. 75% of 4 Revegetate high priority sites (page 12) private river frontage upstream of the estuary is also fenced. Y 30,000 locally native plants have been planted.
It is intended that this will be further action to be undertaken by Develop strategy for protection of heritage 5 Council once the planning scheme review/Glenelg Strategic N sites (Page 13) Futures Plan is completed.
Review trigger level to commence application There will be no review of the trigger level until the Estuary 6 N for approval to breach river mouth Entrance Management Support System has been completed.
Review existing development, including Upgrade of the Caravan Park septic system will take place in late 7 caravan park’s sewage and grey water N 2007. disposal (page 18)
Review location and serviceability of assets 8 associated with the Narrawong Caravan Park N (page 14)
Fox baiting for the Hooded Plover project is underway. The area in a priority area of rabbit management, which means funds are available to landholders for works. The Portland Gorse Group Continue existing programmes of weed and Low 1 has been established and extension and compliance actions are Y feral animal control (page 10) being undertaken. In the Narrawong area, Divided Sedge ( Carex divisa ) will be assessed and proposed for inclusion on the Victorian Noxious Weed List.
No estuary specific water quality indicators have been developed. Identify strategies to reduce water quality 2 ISC monitoring of water quality at one site in the Surry River, N indicator levels upstream of the estuary indicates that water quality may be good.
90% of private estuary river frontage is now fenced. 75% of 3 Revegetate lower priority sites (Page 12) private river frontage upstream of the estuary is also fenced. Y 30,000 locally native plants have been planted.
Protect heritage sites and develop interpretive 4 N material
Develop an interpretative walk around the 5 N estuary foreshore
Develop ‘inundation’ and ‘land subject to There are no existing inundation or land subject to inundation 6 inundation’ overlays for use in local planning overlays in the planning scheme, however the Surry estuary flood N scheme (page 17) study has recently been completed.
Once stage 2 of the heritage study has been completed, a formal amendment process will be undertaken in relation to Protect heritage sites and develop interpretive incorporating these sites into the heritage overlay under the 7 N material (page 15) planning scheme provisions. This is likely to be a detailed and thorough process due to the potential number of sites proposed to be listed in the heritage overlay.
60 Surry Estuary Management Plan APPENDICES
Implemented? Priority No. Action Comments (y/n)
As many of the actions identified in the plan have not been Implement a monitoring programme for each implemented, there have been little to no monitoring programs 8 N strategy in the restoration plan (page 19) established. A monitoring program has been established to monitor water quality in the estuary on a monthly basis
Surry Estuary Management Plan 61 APPENDICES
Appendix G – Fish species recorded in the Surry estuary
This list has been compiled from Alistair Becker’s PhD study on the Surry estuary (unpublished).
Common name Scientific name FFG EPBC VROTS Australian smelt Retropinna semoni Black bream Acanthopagrus butcheri Blue spot goby Pseudogobius olorum Bridled goby Amoya bifrenatus Common galaxias Galaxias maculatus Eastern Australian salmon Arripis trutta Flatheaded gudgeon Philypnodon grandiceps Short-finned eel Anguilla australis Small mouthed hardyhead Atherinosoma microstoma Southern pygmy perch Nannoperca australis Tamar River goby Favonogobius tamarensis Tupong Pseudaphritis urvillii Yellow-eye mullet Aldrichetta forsteri
Fish usage of estuaries Estuaries are a unique habitat, where environmental conditions can range from completely fresh to saline. Some estuaries can become hypersaline, with a salinity concentration greater than that of seawater. These diverse and varying conditions provide habitat for a variety of species, from marine opportunists that gain access via river mouth openings, to estuarine and freshwater fish. Marine opportunists are usually juveniles of marine species that utilise the benefits provided by estuarine habitats to complete a stage in their life cycle (See Figure 13). Estuarine species are those that complete their whole life cycle within the estuary, while some freshwater species can be found in the upper reaches (See Figure 14). Other species may use the estuary as a migratory route between freshwater and seawater or vice versa. An example is the Short-finned Eel ( Anguilla australis ) that migrates from freshwater to the sea from summer to autumn to breed in the Coral Sea (Allen et al. 2002). Adults die after breeding, but juveniles make their way to the estuaries, where they migrate up-stream into freshwater areas, sometime between October and January (Allen et al. 2002). Adults migrate to the sea in winter months, aided by floodwaters (McDowall 1996)
Other species may enter or “visit” estuaries as adults for short periods, although they are not dependent on estuaries for any specific stage of their lifecycle. Mullet are an example of marine visitor species to the Glenelg estuary (See Figure 15).
One of the most important functions estuaries provide is to act as a ‘nursery’ for juvenile fish. For an area to function efficiently as a nursery there needs to be a low number of predators and a large amount of food. Estuaries and their associated wetlands fulfil these requirements due to their high productivity and relatively shallow nature. This nursery function is particularly useful to marine opportunist species that can enter the estuary as juveniles, or larvae, when the river mouth is open (See Figure 13). The level of predation in an estuary is much lower than in the marine environment, so juveniles have a greater survival rate in the estuarine habitat. Once grown to a relatively large size, these fish return to the marine environment where their larger size reduces the risk of predation. Examples of marine opportunists include Sea Mullet ( Mugil cephalus ), Yellow-eye Mullet ( Aldrichetta forsteri ) and East Australian Salmon ( Arripis trutta ). The species of fish recruited into the estuarine system will depend on the season the mouth is open, and the period of time it remains open. Figure 13 shows the lifecycle pattern for a typical marine opportunist.
62 Surry Estuary Management Plan APPENDICES
Figure 13 Life cycle of marine opportunists, e.g. mullet (adapted from Swan River Trust, 1999)
Figure 14 Life cycle of an estuarine species, e.g. Black Bream (adapted from Swan River Trust, 1999)
Figure 15 Marine visitors (adapted from Swan River Trust, 1999)
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Appendix H – Estuary water quality monitoring
Chemical Monitoring Season Parameters Frequency Sites Comments Winter - Total Nitrogen (TN), Total Monthly 1 site at Allows for nutrient inputs Spring Phosphorus (TP), Turbidity NTU; freshwater limit from catchment to be Flow rate (Q) approximated June to November Winter - Turbidity NTU; Total Dissolved Monthly profiles 7 Estuary sites Profiles are to be done at Spring Solids, Dissolved Oxygen; each estuary site: a mid Temperature, pH surface layer and a mid June to bottom layer to identify any November occurrence of stratification Summer- Turbidity NTU; Total Dissolved Monthly profiles 7 Estuary sites Profiles are to be done at Autumn Solids, Dissolved Oxygen; each estuary site: a mid Temperature, pH surface layer and a mid December bottom layer to identify any to May occurrence of stratification
64 Surry Estuary Management Plan APPENDICES Appendix I - State Environment Protection Policy Guidelines of Victorian Estuaries
Total P Total Total N Dissolved Chlorophyll Dissolved Transparency/ Suspended Turbidity inorganic inorganic N a Oxygen PAR Solids P attenuation (µg/L) (µg/L) (µg/L) (µg/L) (µg/L) % M (µg/L) (NTU) 75 TH 75 TH 75 TH 75 TH 75 TH Max Min 75 TH percentile 75 TH 75 TH percentile percentile percentile percentile percentile percentile percentile Estuaries ≤ 30 ≤5 ≤300 ≤30 ≤4 80 110 ≥R25 ≤R75 ≤R75 and Inlets
R75 and R25 means that a single objective value could not be specified due to a lack of data or a variability of data collected in a segment. For these areas, the objective needs to be calculated and is the 75 th and 25 th percentile of data collected at reference sites. Reference sites are sites within segments that characterise background (or natural) levels, desirable conditions or the best available sites in that segment.
Appendix J – Maximum daily flow (ML/day) recorded at the Woolwash gauging station from 1975 to 2006. Maximum daily flow is ordered from highest flow, which occurred in 1976, through to lowest recorded flow which occurred in 2006.
Year Flow (ML/day) 1976 3903.465 1981 2732.412 1992 2648.209 1983 2612.226 2004 1941.933 1996 1888.775 2001 1847.595 1984 1628.835 1990 1469.607 1994 1451.09 2000 1438.988 1975 1424.136 1991 1264.774 1977 1232.078 1979 1231.971 1986 1227.485 1989 1104.74 1988 1085.219 1978 992.217 1995 942.634 1987 686.776 1993 555.733 1997 543.119 2003 495.035 1980 451.535 1998 446.745 1985 312.794 2002 248.109 2005 131.105 1999 122.593 1982 54.07 2006 20.782
Surry Estuary Management Plan 65 APPENDICES Appendix K – Works on Waterways and Coastal Management Act consent – estuary entrance management and artificial river mouth openings
Works on Waterways permit Works on Waterways permits provided under the Water Act 1989 expire one year from the date of issue. A copy of a standard license is included in Appendix L.
Works on Waterways permits stipulate a number of conditions that must be met prior to undertaking an artificial mouth opening. The principal condition is that a mouth opening cannot be considered until the water level in the estuary has reached a certain level, referred to as the “trigger level”. For the Surry estuary, this level has been set at 1.165m AHD, which is measured on the gauge board located on the Princes Highway Bridge. A common misunderstanding is that the trigger level defines the level at which the river mouth is automatically opened by artificial means - which is not the case.
Before an artificial opening can go ahead, there are a number of other conditions on the permit that must also be met. These conditions have been established to lower the risk of damage to estuarine processes and biodiversity. Figure 9 shows some of the factors that need to be considered when artificially opening an estuary entrance which include depth of oxygenated surface water, dissolved oxygen level in fringing wetlands and freshwater inflow.
Following attainment of the trigger level, assessment of the water quality conditions within the estuary is the next most important consideration in the process of artificial river mouth opening (ARMO). This is due to the often stratified nature of water quality in the estuary. Removal of the oxygenated top layer of water from the system is the most immediate risk to biodiversity when conducting ARMO. This can result in mass fish kills, such as those seen in the Surry estuary in 1997, 1999 and 2005. The degree and extent of stratification in an estuary is controlled by many factors, including tidal inputs, freshwater inputs and weather conditions, which is why assessment of these factors is included in the list of licence conditions.
Coastal Management Act Consent Along with a Works on Waterways permit, consent must also be obtained under the Coastal Management Act 1995 for the use and development of those areas that are coastal Crown land. The Coastal Management Act 1995 is administered by the Department of Sustainability and Environment. Coastal Management Act consent for artificial river mouth openings can be given for up to 5 years.
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Appendix L – Works on Waterways Permit Glenelg Hopkins CMA 79 French Street, Hamilton, Victoria, 3300 Ph: 03 5571 2526 Fax: 03 5571 2935 web-page: www.glenelg-hopkins.vic.gov.au
WATER ACT - 1989 (Sections 160,161 and 219)
PERMIT No:WW/07/0050 (Issued under By-law No:....1...... )
Subject to the conditions listed overleaf, the Glenelg Hopkins CMA authorises:
Parks Victoria 8-12 Julia St PORTLAND VIC 3305
to construct and operate the following works:
A River Mouth Opening
on the following waterway at a site in, or adjacent to, the land described below.
Waterway: Surrey River...... State Waterway No: 37/6......
Lot(s):CA5 ...... Plan of Subdivision:......
Allotment(s): ...... Section :......
Parish/Township: Narrawong ...... E:561,300….N:5,765,200 ......
NOTE
1. With regard to River Mouth Openings: • this permit is issued for a period of 12 months. River Mouth Openings may occur as many times as required in the 12 month period subject to the conditions of this permit being met on each occasion. • It is the responsibility of the permit holder to obtain written consent under section 40 of the Coastal Management Act 1995 prior to the commencement of works to artificially open the river mouth. NOTE: This consent will be issued by DSE for all coastal crown land other that which is managed by Parks Victoria.
2. The Authority accepts no responsibility for any claims, suits or actions, arising from injury, loss, damage or death, to any person or property which may arise from the construction, maintenance, existence or use of the works.
3. The extent of the review by the Authority of the works identified above, has been confined to a limited evaluation of the affect of the works on erosion in the waterway and flooding of adjacent lands and in particular has not included an evaluation of the structural soundness of the works.
...... Authorising Officer Date of Issue Surry Estuary Management Plan 67 APPENDICES ARTIFICIAL RIVER MOUTH OPENING Permit Conditions
1. The permit holder shall notify the Glenelg Hopkins CMA by E-mail to the address below of attainment of the trigger level and provide an intended date and time for an artificial river mouth opening in accordance with conditions 2 to 10 inclusive and any Special Conditions set out below.
2. Water quality data as specified under Special Conditions below must be collected and forwarded to the E- mail address specified above not more than 24 hrs before an artificial river mouth opening and not more than 48hrs after an artificial river mouth opening.
3. Artificial opening of the river mouth shall not commence prior to the receipt of final approval for the artificial opening from the Glenelg Hopkins CMA. Final approval from the Glenelg Hopkins CMA will be issued in writing by E-mail with verbal confirmation of approval via phone message to the permit holder.
NOTE: Final approval from the Glenelg Hopkins CMA will be dependant on the assessment of risks to environmental, social and economic assets as highlighted by the Estuary Entrance Management Support System (EEMSS) . The EEMSS accounts for the following:
• Risk of significant impacts of high water level on private and public infrastructure • Risk of disruption of to social , recreational or cultural activities • Risk to the long term health of the estuary including fish, birdlife and vegetation
4. All works are to be supervised by the WoW permit holder.
5. The release of water from the estuary to the ocean as a result of the artificial opening works is to be timed as near as practicable to coincide with the peak of high tide.
6. It is the responsibility of the permit holder to ensure that any person(s) conducting works be made aware of and comply with the requirements and conditions of this permit. A copy of any permits and conditions shall be kept on site and be easily accessible for the duration of works.
7. Works shall cease immediately upon the discovery of any suspected human remains. The police or State Coroner’s Office must be informed of the discovery without delay. If there are reasonable grounds to suspect that the remains are aboriginal, the discovery must also be reported to Aboriginal Affairs Victoria.
8. Works shall cease immediately upon the discovery of any aboriginal cultural material. Upon any such discovery Aboriginal Affairs Victoria shall be notified immediately and works suspended until advice from Aboriginal Affairs Victoria is received.
9. Aboriginal Affairs Victoria officers shall be permitted access to the site at any reasonable time.
10. Any archaeological relics or evidence discovered during the course of the works, shall be reported to the Executive Director of Heritage Victoria as soon as practicable, and works suspended until advice from Heritage Victoria is received.
68 Surry Estuary Management Plan APPENDICES
Special Conditions Surrey River Mouth
1. The mouth of the Surrey River shall not be artificially opened until the water level is above the agreed trigger level of 1.165m AHD as measured on the gauge board located underneath the Princes Highway bridge.
2. Measurements of dissolved oxygen, salinity and temperature are to be collected at 0.5m intervals from the waters surface to the bed of the estuary at the following sites extending from the river mouth to Wades Rd Bridge.
• E1 South of Panozzos Rd. (E558946 N5765216) • E2 Princes Highway Bridge (E560850 N5765505) • E3 Narrawong Camping Reserve (E561423 N5764581) • E4 Wades Rd. Bridge (E558173 N5766541) • E6 Opposite powerlines (E558333 N5765936) • E9 Adjacent to clearing upstream of campground (E558240 N5765602) • E11 Bend in river after first trees (E558018 N5765083)
3. The permit holder shall obtain the approval of all appropriate authorities and landowners to gain access for machinery to the river mouth area.
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