ENVIRONMENTAL AUDIT
MERRI RIVER ESTUARY
FINDINGS AND RECOMMENDATIONS
ENVIRONMENTAL AUDIT
MERRI RIVER ESTUARY
Findings and Recommendations
EPA Victoria 40 City Road, Southbank Victoria 3006 AUSTRALIA
April 2004
Publication 945 ISBN 0 7306 7642 0
EXECUTIVE SUMMARY the impact of the inputs on the estuary’s beneficial uses. An assessment of the current management An environmental audit is an assessment of the frameworks to protect these beneficial uses is nature and extent of harm (or risk of harm) to the presented and recommendations made to environment posed by waste, substance or noise or contribute to improved management. by an industrial process or activity.
Many organisations use environmental audits as Audit Findings one of a range of tools available to assist in The audit found that the Merri River Estuary is assessing the condition of the environment they adversely impacted upon by land use activities in manage (or can influence), prioritise actions to the catchment of the Merri River. The lack of reduce risks to the environment as a result of their biological and water quality data for the estuary activities or to demonstrate accountability to third significantly reduced the auditor’s ability to quantify parties. the extent of this impact. Subsequently, the This environmental audit of the Merri River Estuary, conclusions reached are primarily based on the conducted by EPA Victoria at the request of the measured water quality impacts of land-use Glenelg Hopkins Catchment Management Authority, activities on the Merri River upstream of the estuary. examined landuses, activities and their associated The activities and land uses examined pose at least impacts on the beneficial uses of the estuary. a moderate risk of harm to the beneficial uses of the The audit was conducted from March to September Merri River Estuary, while the risks to the following 2002. Issues examined included current uses are considered high: environmental condition of the estuary, pollutant • the maintenance of the aquatic ecosystem; inputs, water extractions, management and • recreational use; and planning for the estuary and physical modifications to the Merri River. • the fishery potential.
The following activities were identified as adversely Background impacting on the beneficial uses of the estuary: The Merri River is located within the Hopkins River • The management of wastewater at basin in South Western Victoria. The estuary is Warrnambool Stock Feeds. This is not in located in Warrnambool. accordance with the site’s Waste Discharge The Merri Estuary is one of four Victorian estuaries to Licence and the wastewater irrigation area be classified as ‘extensively modified’ by the defined in the Waste Discharge Licence is not National Land and Water Resources Audit. consistent with EPA Publication 168 Guidelines for Wastewater Irrigation. This environmental audit report identifies hazards that may affect the estuarine waters of the Merri • Direct cattle access to waterways in the River, and presents a qualitative risk assessment of catchment. This was identified as a likely
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source of nutrients in the waterways. Financial • The study ‘Environmental Flow incentives are available for landowners wishing Recommendations for the Merri River South- to construct fencing to exclude stock from West Victoria’, undertaken to determine the waterways however there is no pro-active environmental flow requirements of the Merri program encouraging farmers to fence River, did not consider the environmental flow waterways. requirements of the estuary.
• Effluent from dairy farms is likely to pose a risk • There are a number of septic tanks in the by increasing nutrients in the waterway. There catchment that have the potential to leak are currently no proactive programs to prevent bacteria and other pollutants into the Merri water pollution from dairy effluent. River.
• Evidence of landfilling in low-lying areas within • In Warrnambool City, the Urban Floodway Zone the Merri Catchment was observed. This could and Land Subject to Inundation overlay may lead to flooding and therefore pressure to open not accurately represent the one in 100 year the estuary mouth. Landfilling has also directly floodplains of the Merri River. This has resulted reduced the size of the South Warrnambool in the floodplains being subject to Wetlands. inappropriate development.
In addition, management practices within the A major research project being initiated at the time estuary could be improved to further reduce the risk, of the audit - the Western Estuaries Classification specifically: Project - found that the biota of the Merri Estuary was comparable to other estuaries in the region that • The responsibility for the management of the drained catchments ranging from largely unmodified Merri and its inputs is shared between many to extensively modified. organisations. This has lead to some aspects being overlooked. There is currently no • Water quality monitoring of the Merri River management plan to specifically address the indicates that activities in the catchment are Merri River Estuary. impacting on the nitrogen and phosphorus concentrations of freshwater sections of the • There is currently no coordinated water quality waterway. monitoring program in the freshwater or estuarine section of the Merri River. Therefore, Recommendations short and long term changes in water quality cannot be identified. The auditor made 37 recommendations for reducing the risk posed to the beneficial uses of the Merri • The limited recent water quality monitoring River estuary. Among these there were 10 data that has been collected by various groups considered high priority and one very high priority. is not readily available to land managers or the These were: public.
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• Until an environmental flow study recommends conducted in accordance with EPA Pub 168 as otherwise, Southern Rural Water should update required by the Waste Discharge Licence. Year- the irrigation roster to ensure that round irrigation, depth to groundwater, environmental flows meet Streamflow wastewater application rates, and water Management Plan requirements (very high budgeting should be included in the scoping; priority); • The Western Coastal Board and Department of • Relevant stakeholders implement the Sustainability and Environment should ensure recommendations in the Glenelg Hopkins that the Merri Estuary Coastal Action Plan and Nutrient Management Plans to ensure that Streamflow Management Plan are integrated to nutrient levels in Merri River are reduced; ensure that environmental flows for the estuary are provided; • Glenelg Hopkins Catchment Management Authority should undertake to proactively • Southern Rural Water should ensure that the educate farmers about the importance of Streamflow Management Plan has fencing waterways to ensure that stock cannot contingencies for periods of drought to ensure gain direct access; environmental flows are protected; and
• EPA and Moyne Shire Council staff should • Glenelg Hopkins Catchment Management implement a proactive program with dairy Authority should consider additional proactive farmers within the catchment to prevent measures to encourage revegetation of the pollution of waterways; catchment.
• EPA and Warrnambool Stock Feeds work together to collect sufficient data to enable an accurate assessment of the environmental impact from the wastewater treatment operations. This should consider impacts from the wastewater stored in ponds and that disposed of by land irrigation;
• Warrnambool Stock Feeds ensure that their wastewater is analysed at least monthly as required by the Waste Discharge Licence;
• EPA and Warrnambool Stock Feeds work together to ensure wastewater irrigation is conducted outside the floodplain of the Merri;
• EPA and Warrnambool Stock Feeds work together to ensure that wastewater irrigation is
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LIST OF ACRONYMS
CBD Central Business District DNRE Department of Natural Resources and Environment DPI Department of Primary Industry DSE Department of Sustainability and Environment DRDC Dairy Research and Development Corporation EPA Environment Protection Authority GHCMA Glenelg Hopkins Catchment Management Authority GHNMP Glenelg Hopkins Nutrient Management Plan GMA Groundwater Management Area LPCRMP Levy’s Point Coastal Reserve Management Plan LSI Land Subject to Inundation MRCRP Merri River Catchment Restoration Plan MSC Moyne Shire Council NLWRA National Land and Water Resource Audit NHT Natural Heritage Trust PAV Permissible Annual Volume SEPP (WoV) State Environment Protection Policy (Waters of Victoria) SGSC Southern Grampians Shire Council SMP Streamflow Management Plan SRW Southern Rural Water SWMP Stormwater Management Plan SWW South West Water SWWLMP South Warrnambool Wetlands Landscape Management Plan VSAP Victorian Stormwater Action Program VWQMN Victoria Water Quality Monitoring Network WCAP Warrnambool Coastal Action Plan WCB Western Coastal Board WCC Warrnambool City Council WECP Western Estuaries Classification Project
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TABLE OF CONTENTS
EXECUTIVE SUMMARY...... I Background...... I Audit Findings ...... I Recommendations ...... I LIST OF ACRONYMS ...... IV TABLE OF CONTENTS...... V 1 INTRODUCTION...... 1 2 OBJECTIVES...... 1 3 SCOPE...... 2 4 APPROACH AND METHODOLOGY...... 2 4.1 Hazard Identification...... 2 4.2 Risk Classification...... 4 4.3 Audit Compliance Criteria...... 4 4.4 Methodology...... 6 5 DESCRIPTION OF ESTUARY AND CATCHMENT ...... 8 6 AUDIT FINDINGS ...... 10 6.1 Management Responsibilities ...... 10 6.1.1 Findings ...... 10 6.1.2 Risk Classification...... 10 6.2 Planning...... 12 6.2.1 Findings ...... 12 6.2.2 Risk Classification...... 13 6.3 Estuary Condition...... 13 6.3.1 Findings ...... 13 6.3.2 Risk Classification...... 14 6.4 River Condition...... 14 6.4.1 Findings ...... 14 6.4.2 Risk Classification...... 24 6.5 Estuary Inputs – Diffuse Rural...... 25 6.5.1 Findings ...... 25 6.5.2 Risk Classification...... 27 6.6 Estuary Inputs – Diffuse Urban ...... 28 6.6.1 Findings ...... 28 6.6.2 Risk Classification...... 31 6.7 Estuary Inputs – Point Source...... 32
6.7.1 Findings ...... 32 6.7.2 Risk Classification...... 37 6.8 Estuary Inputs – Marine...... 38 6.8.1 Findings ...... 38 6.8.2 Risk Classification...... 38 6.9 Water Extractions ...... 38 6.9.1 Findings ...... 38 6.9.2 Risk Classification...... 43 6.10 Physical Modifications to Catchment and Watercourse ...... 44 6.10.1 Findings ...... 44 6.10.2 Risk Classification...... 47 7 RECOMMENDATIONS ...... 48 REFERENCES...... 55 GLOSSARY...... 57
APPENDIX 1 Location Map APPENDIX 2 Catchment Map APPENDIX 3 Aerial Photo of Estuary APPENDIX 4 Planning Zones APPENDIX 5 VWQMN Data APPENDIX 6 EPA Water Quality Monitoring Data APPENDIX 7 Russell’s Creek Nutrient Levels APPENDIX 8 Average Monthly Rainfall at Warrnambool Airport APPENDIX 9 Merri River Irrigation Roster
MERRI RIVER ESTUARY
1 INTRODUCTION over the audit period (March to September 2002). The audit conclusions are based primarily on data The Australian Catchment, River and Estuary obtained from the Western Estuaries Classification Assessment 2002, a report of the National Land and Project and the auditor’s assessment of Water Resource Audit, classified the Merri Estuary as management practices. Audit findings, including 'extensively modified'. The Merri was one of four qualitative assessment of potential risks, are Victorian estuaries to receive this classification. presented in Section 6. An environmental audit of the Merri River Estuary The audit process is different from a purely scientific was conducted by EPA in the period March to study in that its assessment involves comparing September 2002 at the request of the Glenelg water quality and management practices with Hopkins Catchment Management Authority. The standards and legislation. An assessment of audit examined landuses, activities and associated possible harm or detriment to the environment is impacts on the beneficial uses of the estuary. then made based on this evidence and on the Issues examined included current environmental opinion of the Environmental Auditor. condition of the estuary, pollutant inputs and water A scientific study involves the author drawing extractions, management and planning for the conclusions based primarily on data gained through estuary and physical modifications to the Merri experimental work or field studies. Further details River. The environmental audit report identifies regarding the audit’s approach and methodology are hazards that may affect water quality and provides a contained in section 4. qualitative risk assessment of the impacts of various land uses and activities in the river catchment on the beneficial uses of the surface waters within the 2 OBJECTIVES estuary. The objectives of this audit were to: The Merri River is located within the Hopkins River - assess the condition of the Merri River basin in South Western Victoria. The total length of Estuary in relation to the protection of the river system is approximately 110km and it has a beneficial uses identified in the State catchment of approximately 1,900 square environment protection policy (Waters of kilometres. The Merri River Estuary is located in Victoria) 1988; Warrnambool. The rural land in the catchment is predominantly used for dairy, cattle and sheep - determine the effectiveness of the current farming. management of the estuary in minimising risk of harm to the estuary; and The environmental audit was undertaken by assessing water quality data and management - to explore and develop the use of practices against relevant standards, legislation and environment condition auditing. management plans. This audit provides a “point in time” assessment of the condition of the estuary
EPA Victoria 1 MERRI RIVER ESTUARY
3 SCOPE - issues associated with biodiversity, and historical values For the purpose of this audit, the Merri River Estuary - estimation of the relative contributions is defined as all surface waters from the mouth of of pollutants (eg bacteriological and the Merri River to the Swinton Street Bridge nutrients) from each land use or activity (including the South Warrnambool Wetlands). - verification of the accuracy of any of the The scope includes identifying the hazards that may data used. affect the estuarine waters of the Merri River, qualitatively assessing the risk of harm to the Observations of the estuary were made and estuary and its beneficial uses caused by inputs to interviews were restricted to the period between the estuary, and assessing the adequacy of current March 2002 and September 2002. The audit management frameworks to protect these beneficial findings are constrained to the information gathered uses. Beneficial uses of water within the estuary at that time. and water quality objectives for these waters are defined in the State environment protection policy 4 APPROACH AND (Waters of Victoria) 1988 (The 1988 Policy) and are METHODOLOGY presented in section 4.3 of this report.
Only management aspects considered necessary to 4.1 Hazard Identification ensure protection of the beneficial uses identified in Hazards identified as potentially causing a risk to the 1988 Policy were assessed in the audit. the estuary originate from the activities and land Aquatic life in streams was considered where uses in the catchment. These are presented in Table relevant to water quality. 4-1. Flows into the estuary were assessed where relevant to the maintenance of aquatic ecosystems. The audit included an assessment of whether environmental flow levels required by the Streamflow Management Plan were being met.
3.1 Constraints and Exclusions
The following issues and details were considered beyond the scope of this audit:
- assessing whether the environmental flow levels required by the Streamflow Management Plan are adequate to protect the beneficial uses of the estuary
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Table 4-1 Table of Hazards
Potential Hazards Potential Cause(s) Potential Impacts(s) Increased Nutrient Levels - Livestock waste Eutrophication - Fertilizer runoff - Leaking septic tanks - Sewerage overflow - Point sources (Stock Feeds, saleyards, race track) Altered Flow Regime - Surface water extraction - Closure of river mouth - Groundwater extraction - Lack of flushing Faecal Coliform - Livestock waste Disease - General agricultural runoff - Leaking septic tanks - Sewerage overflow - Point sources (Stock Feeds, saleyards, race track) Decreased Dissolved Oxygen Algal Blooms Fish Kills Levels Obstruction of Migratory Fish Bromfield Street weir Fish unable to reproduce Loss of Native Vegetation - Land clearing Lack of appropriate habitat - Weed invasion Loss of Habitat - Landfilling Flooding - Accumulation of sand at estuary mouth Gross Pollutants Littering Aesthetics Sediment - Construction Sites Reduced appropriate habitat - Removal of bank vegetation Flooding
EPA Victoria 3 MERRI RIVER ESTUARY
4.2 Risk Classification 4.3 Audit Compliance Criteria
A qualitative risk classification was used to identify The environmental quality of the Merri River Estuary the magnitude of risks to the estuary caused by was assessed against the beneficial uses, water activities and land uses in the catchment. This was quality indicators and objectives contained in the then used to assign priorities to the State environment protection policy (waters of recommendations provided in this audit report. The Victoria) 1988. risks caused by the activities and land uses have A draft version of the updated policy was released been categorised as set out in Table 4-2. for public comment in December 2001 and There is little systematic or consistent data on water subsequently declared in June 2003. At the time of quality or ecosystem health available in relation to conducting this audit it was appropriate to make the Merri River Estuary. However, the data available assessments against the provisions of the 1988 together with the observations made during site Policy. However, comments have also been made visits were sufficient to perform a qualitative risk on whether objectives of the 2001 draft policy have classification. been met.
The auditor’s judgement was used when The 1988 Policy identifies beneficial uses to be determining risk classifications and presenting protected in various segments in the existing Policy some of the findings in the report. area.
Table 4-2 The beneficial uses identified in the 1988 Policy for estuarine segments are: Activities, practices or estuary High • Maintenance of natural aquatic ecosystems inputs which pose an and associated wildlife: immediate and acute risk to the - wide safety margin (level 3) environment • Water based recreation: Activities, practices or estuary Moderate - primary contact (eg swimming, water inputs that pose an ongoing skiing) risk to the environment - secondary contact (eg boating, fishing) Minor opportunities for Low - aesthetic enjoyment (eg walking by the improvement of management waters) systems, in order to further • Production of molluscs (mussels, oysters, reduce low risks to the scallops, squid, abalone) for human environment consumption • Commercial and recreational use of edible fish
and crustacea • Industrial water use
Environmental Audit 4 MERRI RIVER ESTUARY
The beneficial uses in the 2001 draft policy are • EPA Waste Discharge Licence EM2 held by similar, however the 2001 draft policy also Warrnambool Stock Feeds P/L. recognises having water suitable for aquaculture, • EPA Waste Discharge Licence EM32140 held by indigenous cultural and spiritual values and non- Nestle Australia Ltd. indigenous cultural and spiritual values as • The Warrnambool Planning Scheme, which sets beneficial uses of estuarine waters. out requirements for the use, development and
The 1988 Policy also includes an attainment protection of private land. The Warrnambool program, which provides a framework to manage City Council administers this scheme. actions to protect beneficial uses. There are • The Moyne Planning Scheme, administered by standards and legislation and many management the Moyne Shire Council. plans that have sections directly or indirectly • Warrnambool Coastal Action Plan (WCAP) 1999, relating to the protection of beneficial uses in the which provides strategic guidance for the use Merri River Estuary. As part of this audit, an and management of coastal land within the assessment of compliance with these documents Warrnambool City Council municipal area. has been made. The relevant legislation, standards • Warrnambool Foreshore Management Plan and management plans are: (WFMP) 1993, which identifies measures to • Glenelg Hopkins Nutrient Management Plan implement and manage development and (GHNMP) 2002, which provides a mechanism resources in the foreshore area. for local communities to develop and • Landscape Management Plan for the South implement actions to control nutrients in their Warrnambool Wetlands (SWWLMP) 1996, which local catchment. adds further detail to general • Merri River Catchment Restoration Plan recommendations made in the Warrnambool (MRCRP) 2000 (Draft), which identifies specific Foreshore Management Plan 1993. waterway issues in a number of areas along the • Warrnambool City Council Stormwater river and provides strategic actions and Management Plan (WCC SWMP) 2001 priorities for these actions. The purpose of this plan is to protect and • Streamflow Management Plan (SMP) for the enhance the local waterways by improving the Merri River 1998 quality of stormwater draining from the urban The function of the streamflow management areas in Warrnambool. plan is to create a balanced and sustainable • Levy’s Point Coastal Reserve Management Plan sharing of the available water resource (LPCRMP) 1998 between all stakeholders (licensed diverters, the environment, water-based recreation and The purpose of this plan is to guide the future aesthetic enjoyment). conservation, development and management of the Coastal Reserve.
EPA Victoria 5 MERRI RIVER ESTUARY
4.4 Methodology the furthest percentile that can be meaningfully used. The audit was conducted using the following methodology: The draft 2001 Policy has water quality objectives for • identifying the environmental condition of more specific geographic areas. The available data the estuary; was compared with the draft 2001 Policy objectives • identifying inputs to the estuary and for the Murray and Western Plains: Lowlands of modifications to the catchment and Glenelg, Hopkins, Portland and Corangamite watercourse; Catchments. • assessing the risk that these inputs and The majority of the water quality data obtained is for modifications pose to the beneficial uses of the non-estuarine sections of the Merri. This data the estuary identified in the 1988 Policy; has been compared with the 1988 Policy indicators • identifying current management and objectives for general surface waters to responsibilities and practices for the determine the condition of the river (the major input estuary and its catchment; into the estuary). • assessing the management of land uses A valuable component was recent monitoring of the and activities within the estuary for estuary undertaken as part of the Western Victorian compliance with relevant legislative Estuaries – Classification and Management requirements and management plans; and Guidelines project being undertaken in partnership • providing recommendations for between Western Coastal Board, Deakin University, management solutions where a risk to the Glenelg-Hopkins and Corangamite Catchment beneficial uses has been identified. Management Authorities, Parks Victoria and the Both the 1988 Policy and the draft 2001 Policy South West Victoria Partnership for Sustainable provide specific water quality indicators and Development. objectives. The 1988 Policy predominantly uses While protection of beneficial uses in the non- objectives for acceptable variations from estuarine sections of the river and catchment are background levels, which allow short-term changes outside the scope of this audit, the Merri River is the in water quality to be evaluated and compared to major input into the estuary and so land Policy objectives. management practices in this area may pose a risk Under the draft 2001 Policy, the approach is to the estuary. generally to compare a percentile from an ambient The only long-term data-set for the freshwater data set, with a percentile from long-term reference sections of the Merri was from the Victorian Water data set. For water quality data, the further a Quality Monitoring Network (VWQMN) which percentile is from the median, the more information contained monitoring data for a range of physical it provides. The number of data points, determines and chemical parameters from 1948 to 1990.
Environmental Audit 6 MERRI RIVER ESTUARY
Although VWQMN data is not available for the Merri River after 1990, monitoring has continued in the nearby Moyne and Hopkins Rivers. As the catchments are similar, (Sherwood per comms 2002) it is likely that similar conditions prevail in the Merri. Recent trends in nutrient levels and dissolved oxygen levels (identified as the most significant water quality risks to the estuary) in the Moyne and Hopkins Rivers were examined.
EPA Victoria 7 MERRI RIVER ESTUARY
5 DESCRIPTION OF ESTUARY The South Warrnambool Wetlands are located west AND CATCHMENT of the estuary mouth and drain into the river downstream from the Stanley Street Bridge (refer The Merri River is located in south-western Victoria Appendix 3, Figure 5-2). in the Hopkins River Basin (refer Appendix 1). It has a catchment of approximately 1,900km2. The river Figure 5-2 South Warrnambool Wetlands rises near Minja North. The main drainage area is from numerous small tributaries in the upper and mid sub-catchment, with more defined waterways present in the lower region. Some of the named and defined tributaries include Tea Tree, Gipsys, Kennedy, Union, Drysdale, Manifold, Russell’s and
Yangery Creeks.
The lower reaches of the Merri River loop around The entire Merri River Estuary, as defined in this Warrnambool, a large regional urban centre with a audit, is man-made. Until 1859, the Merri River population of approximately 29,500. entered the ocean at Levy’s Point South of
Lake Pertobe in Warrnambool (refer Figure 5-1) Dennington (refer Appendix 3). In an attempt to drains into the Merri River approximately 1 km from prevent the harbour filling with sand, the course of the river mouth at Pickering Point (refer Appendix 3). the Merri was diverted in 1859 and it now flows The Lake is one of Warrnambool’s main tourist through a man-made cutting and enters the sea into attractions and is located centrally in the City. Lake Stingray Bay, South Warrnambool (refer Appendix 3, Pertobe comprises three lakes, one of which is man- Figure 5-3 and Figure 5-4). Stingray Bay is small and made. The area was originally marshy wetlands that sheltered and offers safe swimming. were linked to the coast and received wash-over Figure 5-3 Estuary discharging into Stingray Bay from Lady Bay.
Figure 5-1 Lake Pertobe
Environmental Audit 8 MERRI RIVER ESTUARY
Figure 5-4 Estuary discharging either side of The catchment of the Merri River has been farmed middle island since 1834. Above Winslow, the predominant land use is dryland grazing for sheep production for wool and prime lambs and beef cattle production. Below, dairy dominates with small areas of cropping of cereal grains such as barley.
There are many small towns in the catchment in addition to the City of Warrnambool, which is a major urban centre. During high flows, water from the Merri River enters Saltwater Swamp and Kelly Swamp. A periodically open second river mouth discharges waters from Kelly Swamp into the ocean at Rutledges Cutting south of Tower Hill. The estuary at Rutledges Cutting is a tidally-dominated (bar) estuary with a seasonal regime of opening and closing. While this estuary is an important and ecologically interesting coastal water body in Western Victoria, it is outside the scope of this audit.
The 1988 Policy defines the estuarine segment as the surface waters between a line drawn across the mouth of the stream at the high water mark on adjacent foreshores to the upstream limit of the saline intrusion. As the limit of saline intrusion varies, so does the boundary of the estuary. Measurements in the field and local expert opinion suggests that the limit of saline intrusion in the Merri River Estuary is no further upstream than the Swinton Street Bridge. The absolute boundary of the estuarine section is the Bromfield Street weir. For the purpose of this audit, the estuary is defined as all surface waters from the mouth of the Merri River to the Swinton Street Bridge (including the South Warrnambool Wetlands and excluding Lake Pertobe).
EPA Victoria 9 MERRI RIVER ESTUARY
6 AUDIT FINDINGS is concerning, and provides potential for management gaps. For this reason the absence of a The findings of the audit are presented in sections co-ordinated framework is considered to pose a covering management responsibilities, planning, moderate risk to all the beneficial uses of the environment condition and inputs to the estuary and estuary. The development of the Merri Estuary its segments. Each section contains a subsection Coastal Action Plan, as recommended in the South describing the audit findings, and a subsection West Estuaries Coastal Action Plan, should address presenting the risk classification output for that this risk. section. The risk classification identifies the risks and management priorities for the relevant section.
A map showing the location of the estuary is presented in Appendix 1.
A map of the river catchment is presented in Appendix 2.
A aerial photo of the estuary is presented in Appendix 3.
6.1 Management Responsibilities
6.1.1 Findings
1. The responsibility for managing the Merri River Estuary and its inputs is shared between many organisations (refer Table 6-1).
2. Many community groups have voluntarily contributed to the management of the Merri River and its catchment. These groups include the Warrnambool City Landcare Group, the Warrnambool Flyfisher’s Club and Friends of Russell Creek Environment.
6.1.2 Risk Classification
The absence of a coordinated management framework for the Merri River Estuary and its inputs
Environmental Audit 10 MERRI RIVER ESTUARY
Table 6-1 Management Responsibilities
Organisation Role/Responsibility Department of Natural Managing the development of statewide policy and strategic directions for Resources and Environment1 natural resource management and the implementation of a range of programs that influence planning and management of public and private land. Environment Protection Development of programs to protect air, water and land from adverse Authority impacts of wastes, and for the abatement of noise and litter. Parks Victoria Parks Victoria is responsible for managing the Merri Marine Sanctuary that extends from the footbridge over the Merri River to offshore beyond Middle Island. Western Coastal Board Development of coastal action plans, facilitating implementation of the Victorian Coastal Strategy and encouraging a coordinated and integrated approach to addressing coastal and marine issues. Glenelg Hopkins Catchment Overseeing the preparation and implementation of regional catchment Management Authority strategies and promoting the sustainable management of land and water resources in partnership with other organisations. Local Government Land use planning, provision and maintenance of stormwater drainage (Warrnambool, Moyne & systems and strategic planning/policy development. Southern Grampians) Southern Rural Water Manages rural water supply from surface and groundwater. South West Water Authority Provides water supply and sewerage services to Warrnambool. Management of algal blooms in the catchment. Framlingham Aboriginal Custody of local sites and places of Aboriginal and cultural heritage. Trust
1 At the time of the audit DNRE was responsible for the management of Victoria’s natural resource base. This agency has since been restructured into DPI and DSE.
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6.2 Planning 1988 State Environment Protection Policy (Waters of Victoria). 6.2.1 Findings 6. An Environmental Significance Overlay – Schedule 2 covers the course of the Merri 3. Under the Victorian Planning Provisions and River from the Stanley Street Bridge to the the local Planning Schemes, the Merri River boundary of the WCC municipality above and its catchment are covered by a variety Woodford. A key environmental objective of of zones and overlays (refer Appendix 4). this overlay is to protect the natural, These planning zones and overlays are cultural and visual values of the Merri River, discussed in more detail below. its tributaries, adjacent land and associated 4. A Public Conservation and Resource Zone habitat corridors. covers the area from the estuary mouth up 7. From the Princess Highway Bridge to to Stanley Street Bridge. A key purpose of Woodford, the course of the Merri River is a this Zone is to protect and conserve the Public Park and Recreation Zone and in natural environment and natural processes some areas, the land immediately adjacent for their historic, scientific, landscape, to the river is an Urban Flood Zone. habitat or cultural values. An Environmental Significance Overlay – 8. Within the MSC, the Merri River and Schedule 1, also covers this area. surrounds are in a Rural Zone. Ecosystem Protecting the natural and cultural values of protection is not a primary purpose of this the coast, and appreciating the complex Zone nature of biological and physical coastal 9. The Warrnambool Planning Scheme processes is an environmental objective to Municipal Strategic Statement identifies be achieved in the area covered by this using local policy to control development overlay. on flood prone land (ie land subject to 5. An Urban Floodway Zone covers the South inundation by a 1:100 year flood). Planning Warrnambool Wetlands, and the River from Controls used by the WCC are the Urban the Stanley Street Bridge to the Princess Floodway Zone and Land Subject to Highway Bridge. A key purpose of this Zone Inundation (LSI) Overlay. The auditor was is to protect water quality and waterways as unable to trace the basis for the areas natural resources in accordance with the covered by the local planning controls. provisions of relevant State Environment Interviews with relevant WCC staff indicated Protection Policies, and particularly in that extent of these areas are largely based accordance with Clauses 332 and 353 of the on local opinion.
2 Relates to potable water supplies. 3 Relates to floodplain management.
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6.2.2 Risk Classification (identified in the 1988 Policy). The WECP classification and assessment system The fact that the MSC Planning Scheme does not included benthic macrofaunal, physio- specifically protect environmental values above chemical parameters and sediment data. Woodford is considered to pose a low risk to aquatic The audit obtained preliminary data (ie for a ecosystems and aesthetic enjoyment of the estuary. single season) for ten sites from forty The fact that the LSI overlay and Urban Floodway estuaries being assessed by this project, Zone may not accurately represent the 1 in 100 year including two from the Merri River estuary. floodplain of the Merri is considered to pose a The preliminary data allowed for a moderate risk to aquatic ecosystem and recreational comparison of the Merri River with eight use, as flood plains may be subject to inappropriate other estuaries in western Victoria (Aire, development. Curdies, Eumeralla, Fitzroy, Gellibrand, Hopkins, Moyne and Surrey Rivers). This is 6.3 Estuary Condition based on the assumption that similar results across the estuaries would indicate 6.3.1 Findings maintenance of aquatic ecosystems. This assumption would not be correct if all 10. There has been no regular monitoring of estuaries are degrading at a similar rate. water quality in the estuary. The data were compared using a series of 11. Two studies provide some insight into the similarity indicies and analyses. The ecological health of the Merri River Estuary benthic macrofauna assemblage of the or similar Western Victorian estuaries. Merri River estuary did not differ statistically These are ‘Estuarine Health Assessment from the other western plains estuaries. using Benthic Macrofauna’ (Moverley and 13. The Australian Catchment, River and Estuary Hirst 1999) and the ‘Western Estuaries Assessment 2002 (a report on the findings Classification Project’ (WECP), which is still of the NLWRA4) states that ‘The small wave- being conducted. Both studies used dominated estuaries common in West estuary biota to create an estuarine Victoria are at risk from inappropriate land classification and/or assessment system, use practices and are in need of targeted however Moverly and Hirst (1999) did not management’. A key need identified in the include the Merri River in their estuarine report is ‘Greater focus on the management health assessment. of Western Victorian estuaries as these 12. The WECP data was used to assess the estuaries are most susceptible to impact Merri River Estuary against the beneficial
use described as “maintenance of aquatic 4 The National Land and Water Resource Audit ecosystems and associated wildlife” (NLWRA) is a program of the National Heritage Trust.
EPA Victoria 13 MERRI RIVER ESTUARY
from land use’. The Merri Estuary was one from these data points, other than to note of four Victorian estuaries classified as that total nitrogen and total phosphorus “extensively modified” in the NLWRA. This seemed high on the few available data. assessment was based on properties such as catchment use and condition, catchment 6.3.2 Risk Classification hydrology, estuary use and level of The risk of the current water qualtiy monitoring modification to estuarine ecology. regime adversely impacting upon the aquatic 14. Two single-time measurements of nutrients ecosystem of the estuary is considered moderate. in the estuarine section of the Merri, (April Due to the lack of regular water quality monitoring in and September 2002, WCEP) did not the estuary, there are insufficient data for the Merri contain enough measures for comparison to River estuary to enable firm conclusions on the the 2001 draft Policy objectives5. The levels current condition of the estuary or short and long of nutrients in these restricted datasets term trends occurring in water quality. showed total nitrogen of 877µg/L (April) and 957µg/L (September). The 2001 draft 6.4 River Condition Policy (EPA 2001) has 75th percentile levels set for total nitrogen in estuaries at •300 6.4.1 Findings µg/L. The total phosphorous was 67 µg/L (April) and 100 µg/L (September). The 16. An investigation of the condition of the 2001 draft Policy has 75th percentile levels stream channel and riparian zone along the set for total phosphorous in estuaries at Merri River and Spring Creek using the •30 µg/L. River, Channel and Environmental (RCE) methodology was undertaken in 1995 by 15. The pH measured during these two Denny as part of an honours project (Denny sampling events was within the range 1995). The river system was classified as specified in the 2001 draft Policy (EPA 2001) poor to degraded along most of its length for lowland streams in western Victoria. In except for one site in the Winslow Gorge April, measurements ranged from 7.09 to that was classified as good. 7.71 and in September measurements ranged from 8.44 to 9.12. However, note 17. The Victorian Water Quality Monitoring that these objectives are for lowland Network (VWQMN) measured a range of streams and not for estuaries where water water quality parameters at Woodford four is more saline and higher pH is expected. It times a year from 1948 to 1990. Since this is difficult to draw any solid conclusions time, EPA, researchers at Deakin University, Waterwatch Victoria and environmental 5 There are no nutrient objectives for estuaries in the consultants have undertaken some limited 1988 Policy. monitoring in the catchment. The VWQMN
Environmental Audit 14 MERRI RIVER ESTUARY
data set is the only data set that is publicly available and the only data set large enough to be compared with percentile objectives. The VWQMN Data is shown in Appendix 5. Water quality monitoring data conducted by EPA is shown in Appendix 6.
EPA Victoria 15 MERRI RIVER ESTUARY
Table 6-2 Comparison with Preliminary Nutrient Guidelines for Victorian Streams (EPA Publication 478, June 1995) and SEPP (WoV) 1988 Objectives
Parameter TP TN DO pH Objective • 0.035 mg/L • 1.000 mg/L • 5mg/L 6.0-9.0 • 50% saturation DATA SOURCE/ Number Number Number Number Location Exceedences Exceedences Exceedences Exceedences VWQMN (1978-1990) Woodford 34 out of 46 18 out of 466 2 out of 152 0 out of 152 McGREGOR (1995) Minja North 5 out of 6 0 out of 6 0 out of 6 0 out of 6 Minja 6 out of 6 0 out of 6 0 out of 6 0 out of 6 Bromfield’s Rd Ford 4 out of 6 0 out of 6 0 out of 6 0 out of 6 Woolsthorpe 5 out of 6 0 out of 6 0 out of 6 0 out of 6 Winslow 6 out of 6 0 out of 6 0 out of 6 0 out of 6 Woodford 6 out of 6 1 out of 6 0 out of 6 0 out of 6 Woolaston Road 6 out of 6 1 out of 6 1 out of 6 0 out of 6 Woolen Mill 6 out of 6 0 out of 6 0 out of 6 0 out of 6 MANFORD (1999-2001) Woodford 4 out of 4 2 out of 47 1 out of 8 0 out of 8 Warrnambool 8 out of 10 1 out of 4 0 out of 4 KOROBLITSAS (2000) 10 out of 10 Rural 1 3 out of 3 2 out of 4 Rural 2 2 out of 2 2 out of 4 Racecourse 5 out of 6 0 out of 4 Urban 1 4 out of 4 0 out of 4 Urban 2 3 out of 6 0 out of 4 S. Urban 4 out of 6 0 out of 4 WATERWATCH (01-02) Nestle 2 out of 2 0 out of 2 Russell Ck – Parkland 4 out of 4 1 out of 4 Caramat Rd 2 out of 3 3 out of 3 Russell Ck – Hopkins Hwy Bridge 3 out of 5 2 out of 5 Bromfield Weir 1 out of 1 0 out of 2 LANDFILL (1999-2002) Site 1 1 out of 18 Site 2 1 out of 1
6 Total Nitrogen obtained by adding Total Kjeldahl Nitrogen and Nitrates and Nitrites. 7 Total Kjeldahl Nitrogen only 8 Total Kjeldahl Nitrogen plus Nitrate only.
Environmental Audit 16 MERRI RIVER ESTUARY
Table 6-3 Comparison with SEPP (WoV) 1988 Suspended Solids Objective
Parameter SS Objective • 25 mg/L (50th percentile) • 80 mg/L (90th percentile) VWQMN Data 3 (50th percentile) 14 (90th percentile) Compliance? YES YES
Table 6-4 Comparison with Draft SEPP (WoV) 2001 Objectives
Parameter TP TN DO pH EC Turbidity Objective • 0.040 mg/L (75th • 0.900 mg/L • 8.3 • 1500 µS/cm • 10 mg/L percentile) (75th percentile) (75th percentile) (75th percentile) (75th percentile) VWQMN Data 0.07 1.165 80.33 7.75 2700 2.95 (75th percentile) (75th percentile) (25th percentile) (25th percentile) (75th percentile) (75th percentile) 118.4 8 (Maximum) (75th percentile) Compliance? NO NO NO YES NO YES NO YES
EPA Victoria 17 MERRI RIVER ESTUARY
18. A large number of measured total nitrogen and Figure 6-6 suggests a generally phosphorous and total nitrogen similar relationship for discharge and total concentrations in the Merri River and its phosphorous. tributaries exceed the objectives for rivers 22. Total nitrogen and total phosphorous levels in the Southwest River Region in the in Russell’s Creek decrease downstream Preliminary Nutrient Guidelines for Victorian (refer Appendix 7). The reduction in nutrient Streams (1995) (refer Table 6-2). 110 out of levels may be due to nutrients being taken the 126 (ie 87%) available total up by vegetation in the creek. phosphorous data points were greater than 0.035 mg/L. 54 out of the 131 (ie 41%) 23. The GHNMP 2002 identifies an action to available total nitrogen data points were investigate the increase in nutrient greater than 1.000mg/L. The VWQMN data concentrations in the Merri River and set exceeded the 2001 draft Policy developing benchmarks for nutrient loads objectives for both total phosphorous and in the river as an ongoing medium priority. total nitrogen (refer Table 6-4). This work has not yet started.
24. The 1988 Policy states “Waters shall be free 19. The VWQMN data for the Moyne and of substances in concentrations that cause Hopkins Rivers indicates that total nitrogen nuisance plant growth or changes in concentrations have remained reasonably species composition to the detriment of the constant in these rivers since 1990 (refer protected beneficial use.” Observations by Figure 6-2). Due to catchment and land use EPA Victoria on the 22 April 2002 showed similarities it is likely that the trend in the nuisance growth of filamentous algae and Merri River has been similar. Azolla sp. above the Broomfield Street weir 20. The VWQMN data for the Moyne and (refer Figure 6-1) thought to be caused by Hopkins Rivers indicates that total high levels of nutrients in the waters. phosphorous concentrations in these rivers Further downstream, above Kiaora9, just have increased since 1997 (refer Figure 6-3). below Woolsthorpe, little or no Azolla sp. Again, similarities in the catchment and and filamentous algae were present. In the their land uses make it likely that the trend opinion of the auditor, this suggests that in the Merri is similar. nutrient levels above Kiaora were not high enough to support these organisms. 21. Nutrients are often bound to suspended particulate matter and turbidity is seen to
peak during periods of high flows (refer 9 A site near the junction of Spring and Bullanbul Figure 6-4). Figure 6-5 shows a positive Creeks that has been proposed by SWW as a correlation between discharge and total possible site for stabilised biosolids application.
Environmental Audit 18 MERRI RIVER ESTUARY
Figure 6-1 Nuisance Growth of Filamentous Algae above Bromfield St Weir
25. A small number of the available measurements of dissolved oxygen levels in the Merri River and its tributaries were below the objectives in the 1988 Policy (refer Table 6-2). Fifteen out of 252 (ie 6%) of the available data points were below 5mg/L or 50% saturation. The VWQMN data did not meet the 2001 draft Policy objectives for dissolved oxygen (refer Table 6-4).
26. The VWQMN data for the Moyne and Hopkins Rivers indicate that dissolved oxygen levels have remained reasonably constant since 1990 (refer Figure 6-7). Due to catchment and land use similarities it is likely that the trend in the Merri River has been similar.
EPA Victoria 19 MERRI RIVER ESTUARY
Figure 6-2 Total Nitrogen Concentrations in the Merri, Moyne and Hopkins
2.5
2
1.5 mg/L 1
0.5
0 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001
Moyne@Toolong Hopkins@Hopkins Falls Merri@Woodford
Figure 6-3 Total Phosphorous Concentrations in the Merri, Moyne and Hopkins
0.16
0.14
0.12
0.1
0.08 mg/L 0.06
0.04
0.02
0 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000
Moyne@Toolong Hopkins@Hopkins Falls Merri@Woodford
Environmental Audit 20 MERRI RIVER ESTUARY
Figure 6-4 Comparison of discharge and turbidity in the Merri River
14000 80
12000 70
60 10000 50 8000 40 6000 30 Turbidity (NTU)
Discharge (ML/day) Discharge 4000 20
2000 10
0 0 1983 1984 1985 1986 Discharge Turbidity
Figure 6-5 Plot of Total Nitrogen against discharge for the Merri River
3.5
3
2.5
2
1.5
1 Total Nitrogen (mg/L)
0.5
0 1 10 100 1000 10000 Discharge (ML/day)
EPA Victoria 21 MERRI RIVER ESTUARY
Figure 6-6 Plot of Total Phosphorous against discharge for the Merri River
0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 Total Phosphorous (mg/L) 0.02 0 1 10 100 1000 10000 Discharge (ML/day)
Figure 6-7 Dissolved Oxygen Concentrations is the Merri, Moyne and Hopkins
10
9
8
7
6
5
4 Concentration (mg/L) Minimum Recorded DO 3
2
977 979 981 983 985 987 989 991 993 995 997 999 001 1 1 1 1 1 1 1 1 1 1 1 1 2 Moyne Hopkins Merri
Environmental Audit 22 MERRI RIVER ESTUARY
Policy for estuarine sections however the 27. All the measured pH levels in the Merri River auditor obtained no measurements of these and its tributaries met the objectives of parameters in the Merri River Estuary: both SEPP (WoV) 1988 (refer Table 6-2) and the draft SEPP (WoV) 2001 (refer Table 6-4). - Dissolved Inorganic Phosphorus (µg/L) - Dissolved Inorganic Nitrogen (µg/L) 28. The VWQMN data set meets the SEPP (WoV) - Chlorophyll a (µg/L) 1988 suspended solids objectives (refer - Transparency Table 6.3). - Transparency/PAR Attenuation (m)
29. The VWQMN data set meets the draft SEPP 33. The 2001 draft Policy has the following (WoV) 2001 turbidity objective (refer Table objectives for biological indicators in 6-4). freshwater sections in the Murray and Western Plains region: 30. The VWQMN data set does not meet the Number of Families Score ≥ 23 draft SEPP (WoV) 2001 electrical SIGNAL Index10 Score ≥ 5.3 conductivity objective (refer Table 6-4). Key Families Combined Habitat Score ≥ 21 AUSRIVAS11 O/E Score 0.87-1.13 The auditor identified two 31. Assessment of E.coli levels against the 1988 macroinvertebrate studies for sections of Policy objectives requires at least five the Merri River. Australian Water samples taken within 42 days and Technologies (2001) determined SIGNAL assessment against the 2001 draft Policy scores for five sites in the Merri River. requires at least five consecutive samples SIGNAL scores at two of these sites were taken within a month. The auditor obtained calculated to be less than the 2001 draft two sets of E.coli measurements in the Merri Policy objective. EPA conducted River (AWT 2000, McGregor 1996). Neither macroinvertebrate testing in 1997 at three of these data sets were large enough to sites in the Merri River. The AUSRIVAS O/E enable a comparison with either SEPP
objective to be made. The highest 10 Stream Invertebrate Grade Number - Average measured E.coli level in the River was Level, which is an index of water pollution based on 800orgs/100ml at Woolsthorpe in 1996. In tolerance of biota to pollution. addition, WCC measured E.coli levels in 11 AUSRIVAS (Australian River Assessment System) is Lake Pertobe on two occasions in October a rapid prediction system used to assess the 2001. The highest recorded level of E.coli in biological health of Australian rivers. AUSRIVAS was Lake Pertobe was 870 organisms/100ml in developed under the National River Health Program the “wading pool”. (NRHP) by the Federal Government in 1994, in 32. Objectives for the following water quality response to growing concern in Australia for parameters are contained in the 2001 draft maintaining ecological values.
EPA Victoria 23 MERRI RIVER ESTUARY
Scores calculated met the 2001 draft Policy 36. The GHNMP 2002 identifies ensuring objectives (refer Table 6-5). continued Waterwatch monitoring and increasing community involvement in Table 6-5 Biological Sampling Data – 1997 – monitoring as ongoing high priority actions. Combined Seasons Edge Woodford Primary School, St Johns Primary
Site OE50 SEPP Compliance School Brauer College, Emmanuel College, Wollaston Road 0.76 0.61- 9 Warrnambool College and the South West (urban) 0.87 Tafe are all currently involved in the Woodford (rural) 0.95 0.87- 9 Waterwatch program. In addition to this, 1.13 Grassmere (rural) 0.93 0.87- 9 the GHCMA 2002-03 Communication 1.13 Strategy identifies a project to increase involvement in Waterwatch activities
34. The GHNMP 2002 identifies the review of through a more diverse range of community current water quality monitoring gauging groups.
stations in the catchment as a high priority 37. The GHNMP 2002 identifies linking action to be undertaken within a year. The information on water quality to landuse plan also identifies implementing a changes and projects undertaken in the monitoring program as an ongoing medium region. A project on water quality and land priority action. The WCC SWMP 2001 use is currently being undertaken by the identifies expanding monitoring programs GHCMA. in the Merri River and Russell Creek as an 38. The WCC SWMP 2001 identifies establishing action. The SMP recommends a monitoring a monitoring program for Lake Pertobe as a program that enables trends in water necessary action. This action has not yet quality, particularly nutrients and salinity be been undertaken. established. It recommends that nitrogen, phosphorous, dissolved oxygen and salinity 39. The draft MRCRP 2000, identifies setting be measured at least monthly. Water water quality criteria for the wetlands and quality monitoring has not yet been lower reaches of the Merri River as a high expanded however the GHCMA is currently priority action. This has not yet been done. undertaking a review of the regional water- quality monitoring network. 6.4.2 Risk Classification
35. The WCC SWMP 2001 identifies The risk of elevated nutrient concentrations from the investigating catchment hydrology and Merri River adversely impacting upon the aquatic eutrophication with a view to on-going ecosystem, recreational use and fishery potential of monitoring of water quality and hydrologic the estuary is considered high. Nutrient regime. This has not yet been completed. concentrations in the Merri River (particularly
Environmental Audit 24 MERRI RIVER ESTUARY
phosphorous) have consistently exceeded SEPP The risk of pathogens adversely impacting any objectives since 1978. beneficial uses of the estuary was unable to be determined by the auditor. This is because there The Merri River is the major input into the Merri River were insufficient data available. Estuary. Therefore the condition of the river directly affects the condition of the estuary. The The risk of high electrical conductivity levels discontinuity of the data and the variety of sampling impacting on any beneficial uses of the estuary is sites and methods used makes drawing absolute considered low. The EC differential between the conclusions difficult. freshwater and seawater is great enough to ensure that stratification occurs in the estuary. However, Nutrients are important for the growth of plants, but high EC levels in the freshwater sections of the Merri when they exceed natural levels, excessive plant may affect estuarine fish that migrate upstream growth and algal blooms can occur resulting in poor during their lifecycle. water clarity and depleted oxygen levels.
The lack of recent consistent and reliable monitoring 6.5 Estuary Inputs – Diffuse Rural data is considered to pose a moderate risk to aquatic ecosystems, recreational use and fishery 6.5.1 Findings potential of the estuary, as short and long term changes to water quality may not be identified and 40. In many areas of the Merri catchment, managed. pasture continues right up to the water’s edge and stock is allowed direct access to The risk of low dissolved oxygen levels in the river waterways. (refer Figure 6-8). This can adversely impacting on any beneficial uses of the affect bank stability and cause estuary is considered low. Although low oxygen contaminants such as nutrients and levels can kill fish and other aquatic organisms, bacteria to enter the water. The breaches of the objectives were rare and minor. Warrnambool Flyfishers Club and These minor breaches may be of concern to the Warrnambool City Landcare Group have riverine environment, they are unlikely to been involved in fencing off areas of the significantly influence the oxygen status of the river to prevent cattle access. Funding for estuary. fencing to exclude stock from waterways is High levels of dissolved oxygen are considered to available through the GHCMA’s Partnership pose a low risk to any beneficial uses of the estuary. Projects. To obtain funding, both sides of High oxygen can indicate a likelihood of algal the waterway must be fenced. blooms. Again, the breaches were minor and although potentially concerning to the Merri River, are unlikely to significantly affect the oxygen status of the estuary.
EPA Victoria 25 MERRI RIVER ESTUARY
Figure 6-8 Direct Stock Access to the River as an ongoing medium-priority action. downstream of Nestle DNRE has a dairy extension officer working in the Merri Catchment region but no extension officers focused on dryland agriculture or horticulture. The dairy extension officer has organised nine field days for dairy farmers in the Glenelg Hopkins Basin in 2000/01 and seven field days in 2001/02. The officer has visited 24 41. The GHNMP 2002 identifies 100% adoption farms in the Merri catchment since June of waste management on dairy farms as a 2000 and has organised a service providers high priority to be completed within 10 meeting to provide education. years. The plan identifies a target of 20% 44. The 1988 Policy requires that all effluent compliance within the first year. A survey from milking sheds be disposed of by land undertaken by DNRE in March-August 2001, irrigation in such a manner as to preclude of a sample of 238 dairy farms in Southwest any polluting run-off to surface waters or Victoria, found that 22% of farms had no pollution of groundwater. EPA’s current role ponds for collecting milking shed effluent in dairy effluent management is largely and only 10% of farms had effective effluent limited to responding to complaints made management systems. A survey in by members of the community. If a 1999/2000, sponsored by Bonlac Foods, significant problem is found, EPA typically produced similar results to the DNRE issues the farmer with a Minor Works survey, showing that 20% of farmers in Pollution Abatement Notice and refers the South Western Victoria had no collection farmer to the DNRE dairy extension officer ponds on their farms. DNRE plan to for advice. DNRE provides EPA with a copy undertake a second survey in 2004 to of any advice given to the farmer in measure progress. response to a Minor Works Pollution 42. The GHCMA indicated that $30,000 was Abatement Notice. EPA has not conducted made available for 10 farms for the any proactive visits to dairy farms in the last installation of effluent treatment systems. 12 months in the region. The auditor was unable to verify this. 45. The GHNMP 2002 identified establishing a 43. The GHNMP 2002 identifies establishing research and investigation program on the extension programs to encourage better impacts of different farming techniques on nutrient management on farms with an water quality as a high priority action to be emphasis on dryland agriculture, dairy completed within 5 years. This project had farms and horticulture in the Moyne Shire not yet been initiated.
Environmental Audit 26 MERRI RIVER ESTUARY
46. The GHCMA, MSC, WCC, DNRE and West Vic Corangamite CMA, GHCMA and Southern Dairy are currently in partnership to conduct Farming Systems in 1999. a project in the Brucknell Creek catchment 49. The GHCMA does not have any records of (a tributary of the Hopkins River) to look at any algal blooms in the Merri River. SWW is the social, economic and environmental currently the responsible authority for algal impact of farm management on the whole of blooms. This is a carry over from when catchment. The CMA anticipates that in the SWW co-ordinated the Waterwatch Program. future, this holistic approach will be used The SWW has a response plan for algal for the whole of the Merri River catchment blooms in their own assets but not for other to determine land use impacts on water water bodies. Depending on the severity of quality. the bloom, the following management 47. The GHNMP 2002 identifies supporting the actions may be undertaken; water quality ‘current project on nutrient loss from monitoring, erecting warning signs or pastures’ as a medium priority to be closing the waterway. completed within 5 years. The project 50. GHNMP 2002 identifies reviewing current referred to is a project on nutrient fluxes algal bloom reporting and development of a from dairy areas in South West Victoria database in the region as an ongoing high being conducted in two experimental sub priority. This has not yet started. catchments. The project is being undertaken by Deakin University with 6.5.2 Risk Classification funding from the DRDC, Corangamite CMA and GHCMA. This project is currently The risk of agricultural runoff containing fertilisers underway. and animal wastes adversely impacting upon the aquatic ecosystem, recreational use and fishery 48. The GHNMP 2002 identifies investigating potential of the estuary is considered high. Direct the impacts of raised bed cropping on stock access to the River and its tributaries is likely nutrient contributions to the catchment and to extenuate this by providing a direct route. Whilst developing BMP guidelines for raised bed some resources have currently been allocated to cropping as low priority actions to be managing dairy effluent, there is no proactive completed within 2 years. DNRE staff programs to prevent dairy effluent entering informed the auditor that there is at least waterways. one farm using raised bed cropping in the catchment. An investigation into the The fact that a number of actions in the GHNMP that environmental impacts of raised bed relate to management of diffuse rural impacts have cropping has not started. A brochure on not yet been undertaken is considered a low risk. ‘Best Practice for Raised Bed ~ Controlled Traffic Cropping’ was produced by DNRE,
EPA Victoria 27 MERRI RIVER ESTUARY
6.6 Estuary Inputs – Diffuse Urban Scheme Municipal Strategic Statement identifies the need to limit the density of 6.6.1 Findings housing development in Bushfield and Woodford in the absence of a reticulated 51. The majority of the Warrnambool CBD sewerage system. Staff interviewed from stormwater discharges into Lake Pertobe via MSC indicated to the auditor that they two large outlets. Flushes of poor quality require secondary treatment12 for all new water from Lake Pertobe could have a subdivisions in unsewered areas. significant impact on the condition of the 55. The SWWLMP 1996 recommends that all estuary. The only monitoring data for the septic tanks or services that drain into the Lake obtained by the auditor was limited natural waterways or wetlands must be E.coli monitoring undertaken in October disconnected and re-directed to the city 2001 (refer Finding 31). The auditors sewerage system. Whilst sewerage is observed lime green algae in one section of available for the majority of the Lake Pertobe during March 2002 which Warrnambool area, including the South indicated eutrophic conditions. Warrnambool Wetlands area, it is unclear if 52. The majority of Warrnambool is sewered, all properties located within the reticulated although some of the outer areas are still sewerage system are connected. SWW using septic systems. does not have information on whether all 53. Urban development, such as the township premises that have access to reticulated of Warrnambool, increases the area of sewerage are connected and local councils impervious surfaces within the catchment. are only notified when new septic tanks are Sealed surfaces and drainage pipes installed. increase the rate at which water is 56. Between 1997-2001 there were 78 transported to the receiving waters. (ie installations of domestic wastewater increased stormwater quantity and system in the WCC’s jurisdiction. Thirty two velocity). Stormwater is likely to carry with of these have secondary treatment (ie reed it litter, nutrients, petroleum products, bed or aerated wastewater treatment faecal matter (from pets and malfunctioning system). The auditor was unable to septic tanks) and other potentially establish if any septic tanks were installed damaging materials. in areas that are serviced by reticulated 54. Warrnambool and Dennington have a sewerage. reticulated sewerage system. Woolsthorpe, Winslow, Woodford, Bushfield and Grassmere are unsewered and rely on 12 Biological treatment process to remove soluble septic tanks. The Warrnambool Planning and colloidal organic matter from wastewater.
Environmental Audit 28 MERRI RIVER ESTUARY
57. A requirement for the installation of septic not yet been undertaken, however the tanks in Victoria is that they are maintained GHCMA Communication Strategy identifies in accordance with the Council Septic Tank regular surveys and community analysis as Permit and the relevant Certificate of an action for 2002-03. Approval13. WCC and MSC do not have any 60. The WCC SWMP 2001 identifies as proactive programs to ensure septic tanks necessary actions, using local newspapers are maintained in accordance with these to run articles on the SWMP and its requirements. outcomes, including best practices for 58. The GHNMP 2002 identifies implementing a households and an article on stormwater community stormwater education program and the impacts of litter. At this point in (including stormwater education within time, there has only been one article schools and assisting schools in urban published on the SWMP in The Standard14 environmental programs) and conducting a on 20/3/02. survey of current community awareness of 61. The WCC SWMP 2001 identifies distributing stormwater quality and current household brochures to households on best practices practices as an ongoing high priority. A for households. The GHCMA has developed Streamclean project (partnership between a brochure on household stormwater issues GHCMA, EPA, community, WCC, MSC, that has been distributed to all households Grampians Shire Council, Glenelg Shire in Warrnambool. Council, Ararat Shire Council, South West 62. The WCC SWMP 2001 identifies producing Waste, Gange Burn Landcare Group and an information brochure that encourages Friends of Russell Creek) began in August stormwater collection and reuse on house 2002 and is due to finish in June 2003. Its lots as a medium priority action. This has objectives include increasing community not yet been done. awareness and understanding of water quality issues. A major component of the 63. The WCC SWMP 2001 identifies using the TV project is a competition to design signs monitor in the council reception area to relating to litter and stormwater. show best practices for households as a necessary action. This has not yet been 59. As part of the Waterwatch program, the done. GHCMA has visited schools to discuss monitoring results and given classroom 64. The GHNMP 2002 and the WCC SWMP 2001 presentations on water quality issues. A identify stencilling drain pit lids as a survey of current community awareness has necessary action. The GHCMA and WCC have provided funding for community 13 Requirement to comply with Certificate of Approval if installed after 1990 14 Local newspaper for the Warrnambool region.
EPA Victoria 29 MERRI RIVER ESTUARY
groups to stencil drains. The majority of pipes before the SWMP was implemented. CBD pit lids have been stencilled (refer A grate is used to catch litter at the end of Figure 6-9). The WCC determines which second outlet, as a GPT cannot be installed drains should be stencilled. The auditor due to hydraulic constraints. was unable to locate any records showing 68. As part of World Environment Day 2001, the which drains had been stencilled. WCC displayed the contents of litter trap baskets as part of its community education Figure 6-9 Side Entry Pit Lid Stencilling in the program on litter. Warrnambool CBD 69. The WCC SWMP 2001 identifies installing litter nets on drain outlets into Russell Creek as an action. The WCC have received Victorian Stormwater Action Program (VSAP) funding to install litter nets on 2-3 main inputs into the Creek, however work has not yet commenced. There are no plans for further nets as the Council anticipates that awareness will replace the need for litter 65. The WCC SWMP 2001 identifies as nets. necessary actions, getting school groups to 70. THE WCC SWMP 2001 identifies placing “No conduct litter audits to monitor litter Littering” signs in the CBD as a required quantities in locations near drain outlets action. Signs are not yet in place. and the Merri River and stencilling selected 71. The WCC SWMP 2001 identifies installing oil side entry pit lids based on their audit and grease traps downstream of the two findings. These actions have not yet been main car parks in the CBD as a necessary conducted. action. This has not yet been done. 66. The WCC SWMP 2001 identifies as 72. The WCC SWMP 2001 identifies constructing necessary actions, installing side entry pit swale drains: traps in key residential areas (ie Sundale Road, Laverock Road and Wellington Street) a. Along the two drains leading into and key areas of the CBD. These actions the South Warrnambool Wetlands; have not been undertaken. b. Below the old Braithwaite Street tip 67. The WCC favours end of pipe gross pollutant site; and traps (GPTs) over side entry pit traps as they c. Below the railway yards, near the have simple maintenance requirements. A end of the Gillies St GPT was installed at the end of one of these
Environmental Audit 30 MERRI RIVER ESTUARY
These drains have not yet been constructed. 77. The WCC SWMP 2001 identifies providing an information brochure on best environmental 73. The WCC SWMP 2001 identifies inspecting practices for management of small industrial and commercial sites from street developments to builders and landowners level to determine higher risk sites and to as a high priority action. In addition to this, confirm further management approaches as the SWMP identifies implementing building a necessary action. The plan also includes approvals that ensure that site actions to hold meetings with individual environmental management plans industries and businesses to review (addressing stormwater runoff, rubbish and practices and advise on improvements. sediment) are implemented as a high- These actions have not yet been done. priority action. These actions have not yet 74. The WCC SWMP identifies developing been done. procedures for maintenance of roads and 78. The WCC SWMP 2001 identifies increasing drains that address stormwater quality as a the enforcement of planning permit very high priority action and developing conditions in relation to requirements at the procedures for park and garden construction phase of multi-lot maintenance. These actions have not yet developments as a high-priority action. been completed. This has not yet been done. 75. The WCC SWMP 2001 identifies as a very high priority action, including requirements 6.6.2 Risk Classification or conditions on stormwater quality aspects in planning permits and ensuring planning The risk of septic tanks in the catchment adversely permits require environmental management impacting upon any beneficial uses of the estuary is plans for the construction phase of considered low. development. Some planning permits for The risk of litter adversely impacting the recreational new subdivisions include requirements use of the estuary is considered moderate. There is relating to stormwater management but so opportunity for litter to enter the estuary directly or far none have required an environmental via other stormwater drains. management plan. The risk of incomplete actions from the WCC SWMP 76. The WCC SWMP 2001 identifies developing adversely impacting upon the aquatic ecosystems a policy to encourage water sensitive urban and recreational use of the estuary is considered design as a medium-priority action and low-moderate. A number of the structural and non- providing brochures on water sensitive structural actions identified in the WCC SWMP have urban design to developers as a high- not yet been completed. priority action. These actions have not yet been done.
EPA Victoria 31 MERRI RIVER ESTUARY
6.7 Estuary Inputs – Point Source Figure 6-10 “Clean” Condensate in Nestle Condensate Storage Tank 6.7.1 Findings
79. Nestle operates a milk dehydrating plant in Dennington (EPA Waste Discharge Licence Number EM32149). The plant is located on the East Side of the Merri River (refer Appendix 3). The auditor identified condensate15 and stormwater from the site to be the main risks posed by Nestle to the Merri River.
80. Condensate from the plant is either discharged to sewer if it considered “dirty” or piped across the Merri River and irrigated
onto a paddock on the West side of the Figure 6-11 Nestle Spray Irrigator Merri River if it is considered “clean”. Currently a visual inspection by the yard gang determines whether the condensate is “clean” or “dirty”. The condensate was an opaque light brown colour (refer Figure 6-10) at the time that the auditor visited the site and was being disposed of by irrigation (refer Figure 6-11).
81. In May 2001, condensate from the Nestle Plant leaked into the Merri River due to the failure of a flange gasket in the pipe across the river. A report on the incident identified a number of corrective actions to ensure
that such a leakage did not reoccur, 15 Condensate results from the milk evaporation including removal of all flanges from near processes on site. The condensate produced is a the riverbank and that the pipe be extended very pure stream containing no salts, minerals or further into the paddock such that any fouling. The condensate has some traces of organic mechanical joint is located well away from material that gives it a milky odour.
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the riverbank. Both of these discharged to the Merri River and “dirty” recommendations have been implemented stormwater is diverted to sewer. The 2001 and the joint is now located 150m from the Nestle Annual Report states that the Nestle river. ‘Yard Gang’ check the stormwater system everyday and calibrate the solids and pH 82. The report also recommends that a turbidity probes regularly. The auditor observed meter, or similar instrument, be installed to evidence to show that turbidity and pH prevent potential contaminants entering the levels are monitored daily and probes are stormwater system. A meter has not yet calibrated weekly. been installed, however it is planned to Figure 6-12 Stormwater monitoring equipment install a meter as part of the ‘golf club project’ (refer finding 83).
83. SWW, Nestle and the State Government are jointly funding a project to pipe wastewater from Nestle’s Dennington factory to the Warrnambool Golf Club where it will be mixed with treated wastewater from SWW’s Thunder Point sewerage treatment plant
and used to irrigate the course. This will not 85. The Nestle Environment Improvement Plan only allow the sustainable irrigation of No 2, identifies the need to undertake a wastewater but will remove the need to pipe stormwater risk assessment to evaluate the condensate across the Merri River for “worst case scenario” and prepare a irrigation. response plan to cope. Environmental 84. Spray drying operations at the Nestle site aspects and impacts of the stormwater can produce fallout, which deposits on system have been documented and ranked rooves and roads around the site. This in order of the risk they pose to the fallout and other surface contaminants are environment. Although a response plan has washed into the stormwater system in the not yet been developed, a stormwater event of rain. Stormwater from the Nestle isolation valve has been ordered, which site is collected in the South West corner allows the stormwater system to be isolated where constant monitoring of the pH and if there is waste discharge. turbidity occurs (refer Figure 6-12). 86. Nestle’s Waste Discharge Licence states Stormwater is considered “clean” if pH is that if the wastewater treatment plant’s between 6.0 and 9.0 and Turbidity is less effluent load exceeds its capacity, than 100 NTU. “Clean” stormwater is untreated wastewater may be discharged to
EPA Victoria 33 MERRI RIVER ESTUARY
a paddock adjacent to the Merri River. EPA Warrnambool (refer Appendix 3). The must be notified if such a discharge occurs. majority of raw material for the rendering This emergency wastewater irrigation has plant is sourced from the licence holder’s occurred once in the last 12 months and abattoir located nearby. It generates EPA was notified on this occasion. approximately 230kL/day of concentrated effluent. This effluent passes through a 87. At the Nestle site, pit lids associated with saveall device to remove gross solids the stormwater system are clearly identified followed by biological treatment through with blue markers (refer Figure 6-13) and three anaerobic ponds (Figure 6-15) in lids associated with sewerage system are series configuration and is then disposed of identified with green markers. by irrigation (refer Figure 6-16). The Figure 6-13 Identification of stormwater pits at irrigation system consists of a number of Nestle fixed sprinklers and a portable sprinkler.
Figure 6-14 Warrnambool Stock Feeds
88. The WCC SWMP 2001 identifies having Figure 6-15 Warrnambool Stock Feeds Wastewater meetings with the managers of Nestle to Pond encourage use of best practices as a necessary action. Although this has not yet been done, Nestle have undertaken a number of actions to minimise the environmental impacts of their stormwater.
89. Warrnambool Stock Feeds (refer Figure 6-14) holds EPA Waste Discharge Licence No. EM2. The company operates a high
temperature rendering operation utilising mixed abattoir material, blood, tallow and fats to produce dried blood, meat and bone meal and is located at Levy’s Point
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Figure 6-16 Warrnambool Stock Feeds Irrigator 92. Since the Preliminary assessment report the company has undertaken a number of actions, a tallow polisher has been installed, an oil and grease separator (hydrocyclone) has been installed at the saveall and the flow cooker condensate has been eliminated. The hydrocyclone was installed without an EPA Works Approval.
The report also includes recommendations 90. The Levy’s Point Coastal Reserve to undertake an irrigation study, complete Management Plan (LPCRMP) 1998 an effluent characterisation and evaluate recommends that the WCC does not renew the best option for future wastewater the Stock Feeds’ lease. This is an error in management by February 2002. These the management plan. The Warrnambool recommendations have not yet been Stock Feeds has a freehold title. completed.
93. The facility is currently trialling the use of a 91. Condition 3.6 of the Stock Feed’s EPA vacuum evaporation system to create a Licence required a report on wastewater distillate from the wastewater that can be management to be submitted to EPA by reused in the boilers for steam generation. August 2000. The report titled ‘A (The remaining concentrated wastewater is Preliminary Assessment of the Wastewater discharged into the pond system.) The Treatment System at the Stockfeeds vacuum evaporation system was installed Rendering Plant’, states that: without an EPA Works Approval. “Insufficient quantitative data was 94. The Stock Feeds’ EPA Licence requires that available concerning either the irrigated site treated wastewater from the discharge pond or the final effluent quality to make an is analysed monthly for BOD, suspended accurate assessment of the environmental solids, TN, TP and electrical conductivity. impact of the treated wastewater from the These parameters were only measured facility. However, it is probable that both twice during the 2001-02 financial year. the infrastructure and management of the 95. The Stock Feeds' Licence requires that irrigation area need improvement to ensure irrigation practices be in accordance with that environmental values in the the requirements of EPA’s Guidelines for surrounding ecosystems are adequately Wastewater Irrigation (Pub 168). protected.” Publication 168 recommends:
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• that wastewater irrigation should not Figure 6-17 Flooding in Warrnambool Stock Feed’s occur within the 1 in 100 year flood plain; Irrigation Area
• that wastewater is not applied to land within 100 meters of a watercourse;
• irrigation should not occur all year round and a water budget be prepared for wastewater irrigation areas;
• that the depth to groundwater in the irrigation area be greater than 1.5m; and
• that wastewater is applied to land at a Figure 6-18 Flooding in Warrnambool Stock Feed’s certain rate depending on the soil type. licensed Irrigation Area The licensed Stock Feeds’ irrigation area is located between the rendering plant and the river (refer Appendix 3). This land is within the 1 in 100 year flood plain and the boundary of the Stock Feed’s licensed irrigation area passes within 10m of the Merri River. In September 2002 (a year of below-average rainfall – refer Appendix 8), the auditor observed this area to be flooded (refer Figure 6-17 and Figure 6-18).
In addition to this, there is no winter storage at 96. The auditor was unable to confirm whether the Stock Feed’s, a water budget had not yet the wastewater treatment ponds are lined. been prepared, wastewater is irrigated all year Due to the location of the premises, the soil round, and the depth to groundwater at the site type of the irrigation area is likely to be very is unknown. The Stock Feed’s Operations sandy. If the ponds are unlined then there Manager stated that, although their licence is a significant risk to both groundwater and allows wastewater to be irrigated within 10m of surface water quality. the Merri River, it is the companies practice not 97. The Warrnambool Stock Feeds site has to irrigate wastewater onto flooded areas. ‘Land for Wildlife status’, as tree planting has been undertaken and grazing cattle have been fenced off from wetland areas.
98. The Warrnambool Woollen Mill was purchased by the WCC in 1994 in a deal to keep the mill operating. The Warrnambool
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Woollen Mill shut down in July 2001 after (refer Figure 6-19). The saleyards are 130 years of operation. The WCC are cleaned manually after each sale day. The currently trying to sell it. A study was contaminated wash down water is manually undertaken in late 2001 to identify potential diverted to sewer. At other times, runoff future uses and development options for from the saleyards (ie stormwater) is the site that would also ensure the woollen discharged directly into the Merri River. The mills’ history and cultural significance was auditor did not observe the cleaning not compromised. The WCC SWMP 2001 process or any monitoring data for the identifies having meetings with the stormwater discharged from the saleyards managers of Woollen Mill to encourage use during the audit. of best practices. This is not appropriate, Figure 6-19 Warrnambool Saleyard as the Woollen Mill is no longer operating.
99. The WCAP 1999 recommends that an investigation into extending the golf course into the trotting track site and relocating the trotting track to the equestrian centre or other suitable location as a high priority. The WCC has applied to Sport and Recreation Victoria for funding to conduct a feasibility study of relocating the harness club (ie trotting track). The auditor was 102. The Warrnambool Trout Farm is operated unable to verify any evidence of this near the Merri River, north of Warrnambool. application. The farm does not discharge any wastewater to the River and is not licensed 100. The Warrnambool Racecourse is located on by EPA. the eastern outskirts of Warrnambool, adjacent to Russell Creek (refer Appendix 6.7.2 Risk Classification 3). A large open drain runs from the racetrack to Russell Creek. The WCC SWMP The risk of Nestle’s procedure for assessing its 2001 identifies construction of a wetland on condensate adversely impacting upon any beneficial the drain adjacent to the Warrnambool uses of the estuary is considered low. At the time of Racecourse as a necessary action. The WCC this audit Nestle’s procedure for determining has received VSAP funding to construct the whether its condensate is “clean” or “dirty” was not wetland but work has not yet commenced. quantitative. Nestle’s qualitative procedure, 101. A large saleyard is located on the northern however, does offer some protection from side of Warrnambool, near the Merri River detrimental impacts.
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The risk of wastewater outputs from the Warrnambool Harbour and viaduct and the Warrnambool Stock Feeds facility adversely resulting accumulation of sand have lead to impacting upon the aquatic ecosystem, recreational the protection of the river mouth from ocean use and fishery potential of the estuary is swells. This is likely to accelerate the build- considered high. Various aspects of the storage and up of sand at the river mouth. The SWECAP disposal of wastewater from the Warrnambool Stock 2002 comments that the Merri River Estuary Feeds facility are not in accordance with EPA is experiencing gradual closure of its Publication 168 and are therefore considered to entrance. pose a high risk. 6.8.2 Risk Classification The risk of the current stormwater management at Warrnambool saleyards having a detrimental impact Accumulation of sand could result in loss of habitat on any beneficial uses of the estuary is consdered and burial of estuarine biota and closure of the low. mouth and flooding of low-lying land. This is considered likely to pose a moderate risk to the 6.8 Estuary Inputs – Marine aquatic ecosystem of the estuary. However, short of removing the Warrnambool Harbour infrastructure, 6.8.1 Findings little can be done to manage this risk. High flows from the Merri during winter months may help to 103. The South West Water Authority flush out the accumulated sand. Warrnambool Wastewater Treatment Plant outfall (EPA Waste Discharge Licence EW18) 6.9 Water Extractions is located approximately 1.5km west of the Merri mouth (refer Appendix 3). The plant 6.9.1 Findings treats wastewater to a secondary standard. An average of 13ML/day of treated effluent 106. Water from the Merri River and its is discharged from the plant into the tributaries has been used for irrigation Southern Ocean. since 1945, however the first licence for 104. South West Water have undertaken a extraction was not issued until 1961. There number of ocean impact studies regarding are no major storages within the catchment the impact of their ocean outfall. These so water to meet irrigation demands and studies have found that the outfall generally domestic and stock requirements is has little impact on water quality away from provided directly from the Merri River and the outfall. its tributaries. Total annual water allocation for removal is 4129.8 ML. In the season 105. The sand at the mouth of the Merri River is 2000/2001 the total extraction of water for being pushed ashore by constructional irrigation from the river was 1317.6ML. waves. The construction of the
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Table 6-6 shows the distribution of water 108. A Streamflow Management Plan (SMP) for extraction within the catchment. the Merri River was finalised in 1998. This was the first streamflow management plan Table 6-6 Water allocated for extraction from the to be developed in Victoria. Merri River 109. The SMP 1998 adopts the environmental Reach Number of Total Maximum flow volumes that were recommended by Extraction Annual Daily Points Allocation Extraction Tunbridge in 1997 (refer Table 6-7). In his (ML) (ML/d) report, Tunbridge notes that ‘because of a Drysdale 5 535 5.1 lack of data on water temperature and Creek concentration, recommended Spring 6 371.5 3.5 environmental flows relate only to Creek Merri River 12 1517.0 31.8 protection of a suitable area or amount of above habitat’. Tunbridge did not specifically Woodford consider environmental flow requirements Merri River 17 1706.3 16.2 for the estuarine section of the River. below Woodford Table 6-7 Summer (November-April) Environmental
Flows for the Merri River Catchment (SMP, 1998) 107. The VWQMN has monitored flow within the
Merri at Woodford since 1984. There is no Location Environ- Flush data available for flows in the river before mental Flow Require- this time. The data shows that flows in the ments Merri River are historically highly variable, Spring Creek with high flows between June and - Grassmere/ 5.0 ML/d - December and low flows between January Winslow Road and May. (Refer Figure 6-20) Bridge
Drysdale Creek Figure 6-20 Merri River Flows at Woodford 1975- - Purnim 4.5 ML/d 7 ML/d 2000 Merri River - Grassmere 6.5 ML/d 18ML/d 10th 50th 90th - Woodford 12.0 ML/d 35ML/d 10000 - Bromfield St 5.0 ML/d 1000 100 Weir 10
Daily Flow (ML) 1
Jan Feb Mar Apr Jun Jul Oct May Aug Sep Nov Dec
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Merri, in the 2000/01 season, DNRE agreed to an interim split environmental flow Table 6-8 Winter (May-October) Environmental system, pending an independent review of Flows for the Merri River Catchment (SMP, 1998) the environmental flow requirements in the Flow Maximum Extraction Rate SMP. The details of the roster for the Up to 100 ML/d 0 ML/d 2000/01 irrigation season are shown in 16 100 ML/d 10 ML/d Appendix 9. The split system, comprising of 500 ML/d 30 ML/d stages 1-6 and 7-9, operated such that for
stages 1-6 of the roster the environmental 110. Rather than enforcing environmental flow flows operated according to the SMP (ie 5 volumes for the five locations, the SMP day average of 12ML/day and not less than stipulates that formal compliance is 10ML at any time). For stages 7-9, required for the environmental flow environmental flows were set at 10ML per recommendation at Woodford (ie 12 ML/d). day over a five day average (and not less During the irrigation period the SMP than 8 ML/d at any time). requires that the flow at Woodford is at least 12ML/d or natural whichever is the 112. The instantaneous flow at Woodford is lesser. An average flow of 12ML/d over any measured and recorded approximately 12 5-day period is permitted if the flow is not times per day. During the 2000/01 reduced below 10 ML/s at any time because irrigation season, the recorded of diversion. In addition, flushes17 are to be instantaneous flow at Woodford was less designated as environmental flows and be than 10ML/day 133 out of 2208 times (ie allowed to pass through the river system. more than 6% of the recorded flows) when the roster was on stages 1-6. There were 111. The SMP provides for rostering and three occasions during the 2000/01 restrictions of licensed diverters when irrigation season that the five day average environmental flows decrease below 20 at Woodford was below 12ML/d and the ML/day. Due to disagreement over roster was on level 1-6. appropriate environmental flows for the 113. Under the Water Act 1989, if a property has
direct access to a waterway then they have 16 The extraction rate may be increased a right to access water for stock and proportionally as flow rates increase between 100 domestic purposes. Stock and domestic ML/d and 500 ML/d. water use only requires a license when 17 Defined as the first two days of an increase in flow there is a crown easement between the levels due to a rainfall event that occurs in the property and the waterway. There is a irrigation period when irrigation is on any form of crown easement along most of the length of rostering or restriction.
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the Merri River, however most diverters for 118. The SMP 1998 recommends that stock and domestic use, do not hold a groundwater licences be issued in licence. Stock and domestic licences are accordance with the State Groundwater not subject to rostering. licensing provisions. The majority of the Merri Catchment is within the Yangery 114. The SMP 1998 requires that rosters be Groundwater Management Area (GMA). reviewed on a daily basis and stages This area was declared a Groundwater announced via ABC radio. Rosters are Supply Protection Area in February 1999. updated daily and communicated to The Permissible Annual Volume (PAV), irrigators via a dedicated ring-in service which is the amount that can be extracted instead of using the radio. This alternative from the GMA on an annual basis, has been was adopted as the radio announcement calculated at 11,500 ML per year. The total was made only once each day and could be amount of water currently allocated through missed by farmers. groundwater licences and estimated stock 115. The SMP 1998 requires that a project to and domestic use is 17,500 ML. SRW specify a winter-fill regime be undertaken undertook a survey of groundwater users before 1999. This has not yet been and estimated that during 1998/99 licence undertaken. There are currently only two holders used 6680 ML (ie 58% of the PAV). winter fill licences (total allocation of No new groundwater extraction licences 500ML) for the Merri because the terrain is have been issued since the GMA was not suitable for water storage. declared. No licence is required for 116. The SMP 1998 recommends that all annual extracting groundwater for stock and diversion licences be updated and reissued domestic use. The Yangery aquifer is to reflect revised conditions of supply principally an unconfined aquifer and thus relevant to the SMP. SRW is currently only influenced by rainfall and atmospheric updating licences when they are transferred conditions. This means that declining water between properties and/or licence holders. levels can affect groundwater/surface water interactions, either by reducing the amount 117. The SMP 1998 requires that a differential of groundwater discharging to surface pricing policy be applied to water supplied systems, or by increasing the amount of as sales within the cap to encourage water seepage to groundwater from a surface trading. This is an error. Differential pricing system. In the draft Yangery Groundwater only applies to regulated systems. The Supply Protection Area Groundwater Merri River is unregulated so temporary and Management Plan (2000), the GMA permanent trading is a private arrangement Consultative Committee conclude that the between individuals. contribution and interaction of groundwater
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to surface water base-flows are principally Figure 6-21 Woodford Monitoring Site unknown. The plan recommends that appropriate surface water and monitoring bore data be assessed. This has not yet occurred.
119. The SMP 1998, requires SRW to ensure that the river is only used as a conduit where there is no adverse impact in the environment. Currently, there is only one
instance where a licence holder is using the Figure 6-22 Woodford Monitoring Equipment river as a conduit. The irrigator uses river water for irrigation and pumps bore water into the river. The individual’s licence contains a condition that the licence holder must demonstrate that the discharge water is at least equal to the quality of the water in the Merri River prior to the discharge commencing (Suspended solids, TDS or EC, Total Nitrogen, Total Phosphorous and DO must be measured.) SRW informed the auditor that due to high nitrogen levels in
the bore water, the irrigator has not been able to discharge bore water into the river 121. The SMP 1998 requires that flows be for the last two seasons. monitored at least weekly at Woodford and 120. The SMP 1998 requires that four flow- the three new sites (only two new sites were monitoring sites be in place at Woodford, installed) when flows are between 10- Spring Creek, Drysdale Creek and the 18ML/day. Flows are monitored at the three Bromfield Street Weir. Monitoring sites are stations daily during the irrigation season in place at Woodford and the Bromfield and on weekdays at other times. Street weir as required by the plan. A third 122. The SMP 1998 requires that meters be monitoring site is in place at Grassmere installed, on all licensed irrigation diversion (confluence of Spring Creek and Drysdale points, in accordance with an Creek). The Woodford monitoring site and implementation plan approved by the gauge are shown in Figure 6-21 and Figure Minister. SRW staff informed the auditor 6-22.
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that all diversion sites with pumps18 are The 1988 SEPP (WoV) states that the management of metered (refer Figure 6-23). Meters are the State’s water resources should provide calibrated when they are made and they are adequate flow patterns to protect identified inspected for maintenance every four years. instream beneficial uses including the maintenance All meters are inspected three times a year of wetlands. The 1988 Policy specifically states that to determine trends in water use. These due regard should be given to the importance of meters cannot be used to determine adequate stream flows in lake replenishment, whether irrigators are complying with roster management of wetlands, and estuarine salinity and conditions. SRW does not proactively flow regimes. ensure that irrigators are complying with the The South West Estuaries Coastal Action Plan 2002 roster, however SRW staff indicated that states that water allocation decisions are important members of the community ring and for estuaries due to the close links between complain to SRW when people have their environmental water flows and estuary health. pumps on too long. Once a complaint is The National River Health Program on Environmental received, SRW staff contact the irrigator and Water Requirements to Maintain Estuarine ensure that they are complying with the Processes identifies ecological processes that roster. reduced estuary flows may cause impacts on Figure 6-23 Example of Diversion Point Meter estuarine ecosystems. These processes include:
- reduced vertical mixing (turbulence) resulting in hostile water-quality conditions at depth;
- extended durations of elevated salinity in the upper-middle estuary adversely affecting sensitive flora and fauna;
- extended durations of elevated salinity in the lower estuary allowing the invasion of marine biota;
extended durations when flow-induced currents 6.9.2 Risk Classification - cannot suspend or transport eggs or larvae; The risk of current flow allocations and rostering - diminished frequency that the estuary bed is system in the Merri adversely affecting the aquatic flushed free of fine sediments and organic ecosystem of the estuary is considered high. material;
- reduced channel maintenance processes; 18 It is impossible to meter diversion sites that do - reduced input of nutrients and organic material; not have pumps.
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- reduced lateral connectivity and reduced Some remnant vegetation exists in the maintenance of ecological processes in water Winslow Gorge. bodies adjacent to the estuary (eg South 124. The GHNMP 2002 identifies implementing Warrnambool Wetlands); bank stabilisation, fencing and revegetation - altered variability in salinity structure; in the Merri River as a medium priority action to be completed within 10-25 years. - dissipated salinity/chemical gradients used for The GHCMA administers funding from NHT animal navigation and transport; and for ‘Partnership Projects’ that provide - decreases in the availability of critical physical- individuals, community groups, habitat features. organisations and industries with technical There is no winterfill regime for the river. However, and financial assistance for community as there are only two winterfill licences on the river based catchment health projects (refer this is considered a low risk to the estuary. Figure 6-24). The funding is subject to conditions such as vegetation buffers, The fact that licences are not being proactively protective fencing, avoidance of stream-bed updated to reflect the requirements of the SMP is and bank disturbance. DNRE have considered to pose a low risk. developed a general species list for Impacts of groundwater extractions are considered revegetating the Merri Catchment and to pose a moderate risk as interactions between specific species lists for Russell Creek and surface water and groundwater systems not well the Winslow Gorge area. It is a condition of understood. partnership projects that species from The inability to collect detailed flow data in Spring these lists are used for revegetation. and Drysdale Creek is considered to pose a low risk Figure 6-24 Partnership Project Sign to the estuary.
6.10 Physical Modifications to Catchment and Watercourse
6.10.1 Findings
123. Approximately 95% of the native vegetation in the Merri River catchment has been removed and alien species of plants and
animals introduced (McGregor 1996). In some areas, native vegetation has been 125. The urban sections of Russell Creek have replaced with willows for bank stabilisation. been channelised and riparian vegetation has been removed. The WCC SWMP 2001
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identifies revegetating sections of the creek A pamphlet on preventing the spread of as an action. The GHCMA has produced a weeds from private gardens has been brochure promoting riparian vegetation and produced for the coastal area around a brochure promoting revegetation along Warrnambool including the South Russell Creek. There have been at least Warrnambool Wetlands. eight revegetation projects along Russell 128. Under the GHCMA’s Waterways Protection Creek in recent years. In addition, gorse By –law, works19 undertaken on designated and willows have been removed (refer waterways (including the Merri River) Figure 6-25), and some sections of the creek require a Works on Waterways Permit. In been fenced off to prevent stock access. issuing these permits, consideration is GHCMA and WCC have made financial given to environmental issues such as contributions to this work and FORCE, erosion, vegetation and weed introduction. schools and the ‘bike club’ have made in 129. The SMP 1988 recommends that actions be kind contributions. taken to ensure that the provision of fish Figure 6-25 Gorse Removal from Russell Creek passages as necessary is considered for all new instream works. The provision of fish passage is an obligatory requirement of a ‘Works on Waterways’ permit. The Bromfield Street Weir, the only major man- made structure on the Merri, has a fish ladder that was constructed 4-5 years ago (Refer Figure 6-26).
126. The SWWLMP 1996 recommends that a weed control and revegetation program for the South Warrnambool Wetlands be developed and implemented. Although the auditor did not observe any evidence of a structured program, the president of the Warrnambool Landcare Group stated that
they have been working in this area.
19 127. The SWWLMP 1996 recommends that This includes works that interfere with the land pamphlets on noxious or invasive plant that is normally covered by that water but does not species that should not be allowed to grow include land abutting on or adjacent to the bed and near the South Warrnambool Wetlands be banks that is from time to time temporarily covered provided to South Warrnambool residents. by floodwaters from the watercourse.
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Figure 6-26 Fish Ladder at Bromfield Weir SRW, WCB, WCC and DNRE for comment. Permits are issued for 12-month periods and the permit holder can open the estuary at any time during the period providing permit conditions are met. Permits would contain conditions to minimise the environmental impact of the opening (eg monitoring for dissolved oxygen, notifying relevant organisations before works commence.
131. The GHCMA is currently developing criteria for artificial opening of all estuaries in the region. The GHCMA communication strategy includes actions to develop an information sheet on the impacts of
opening estuaries and a fact sheet on the 130. The South West Estuaries Coastal Action procedure for opening estuaries. Plan 2002 states that ‘estuary mouth 132. The auditors observed evidence of management is a significant issue significant landfilling in low-lying areas of associated with the management of the Merri River floodplains (refer Figure estuaries along the south west coast of 6-27). The SWWLMP 1996 recommends that Victoria and is a trigger associated with the actions be taken to ensure that no majority of the other impacts or threatening additional landfilling occurs within the processes on estuarine ecology and health’. floodway zone without the permission of A Works on Waterways permit, issued by WCC and DNRE. Under the Planning GHCMA, is required to artificially open the Scheme landfilling in flood zones and land Merri River Estuary mouth. WCC, formerly subject to inundation overlays is subject to responsible20 for management of the a Planning Permit. These works also require estuary mouth, last applied for a permit in a Works on Waterways Permit from the 1999. The mouth opened while the permit GHCMA. Applications for both of these application was being considered. It is not permits are referred to DNRE for comment. known whether it was illegal or natural. The auditor did not observe any evidence of Permit applications would be referred to this referral process. Currently, no organisation conducts proactive 20 Parks Victoria is responsible for the management investigations into illegal landfilling. of the estuary mouth. However, WCC responds to complaints
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made by members of the community. study into the effects of flooding on the Complaints are followed up with a letter and ecosystem of wetland areas as a medium a site meeting with the responsible priority action to be completed within 2-3 person/s (usually in conjunction with years of the plan being implemented. GHCMA and DNRE). 6.10.2 Risk Classification Figure 6-27 Landfilling near South Warrnambool Wetlands The risk of poor vegetation cover in the catchment adversely impacting the aquatic ecosystem and recreational enjoyment of the estuary is considered high.
Landfilling is also considered a high risk to the aquatic ecosystem, recreational enjoyment and potential fishery of the estuary as it leads to flooding and therefore pressure to open the estuary mouth. Artificial opening on the mouth may lead to lack of
oxygen and fish kills. Landfilling in the South 133. Although not verified by the auditor, GHCMA Warrnambool Wetlands is directly reducing the size staff indicated that they run information of the wetlands and destroying this habitat. sessions for earthmoving contractors to educate them about illegal landfilling in flood zones.
134. The WCAP 1999 identifies commissioning a floodway study to determine appropriate use and development of low lying land in South Warrnambool utilising floodplain mapping currently being prepared by DNRE as a high priority recommendation. Current boundaries of Land Subject to Inundation Overlays and Urban Floodway Zones in the planning scheme are based on hearsay. The WCC have engaged a consultant to undertake a floodway study on Russell Creek and a small area of the Merri but there is no floodway study being undertaken for South Warrnambool. The Draft MRCMP 2000 identifies undertaking a
EPA Victoria 47 MERRI RIVER ESTUARY
7 RECOMMENDATIONS
High nutrient levels, altered flow regimes, landfilling and litter have been identified as high risks to the protection of beneficial uses in the estuary. The following recommendations are made to reduce the risk of these on the beneficial uses of the Merri River Estuary:
1 Recommendations – Management Responsibilities Priority Relevant Finding 1.1 Glenelg Hopkins Catchment Management Authority should develop a Merri MOD 1 Estuary Coastal Action Plan in consultation with other stakeholders to ensure that the overall management of the estuary and its inputs is managed. 2 Recommendations – Planning 2.1 Moyne Shire Council should amend the Planning Scheme so the Merri River LOW 8 and its tributaries are zoned appropriately so that environmental values are specifically protected. 2.2 Warrnambool City Council should review Land Subject to Inundation Overlays MOD 9 and Urban Flood Zone boundaries to ensure that they accurately reflect 1 in 100 year flood plains. 3 Recommendations – Estuary Condition 3.1 The estuarine sections of the Merri should be included in the regular MOD 10 monitoring program referred to in Recommendation 4.1. 4 Recommendations – River Condition
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4.1 Glenelg Hopkins Catchment Management Authority should co-ordinate the MOD 34, 35, 36, establishment of a regular water quality monitoring program to enable 38 compliance with SEPP objectives to be assessed. This monitoring program should include the freshwater and estuarine sections of the Merri, Lake Pertobe and the South Warrnambool Wetlands. It is recommended that the following parameters be measured at regular intervals at least 12 times per year: - Total Phosphorus (µg/L) - Dissolved Inorganic Phosphorus (µg/L) (estuarine section only) - Total Nitrogen (µg/L) - Dissolved Inorganic Nitrogen (µg/L) (estuarine sections only) - Chlorophyll a (µg/L) (estuarine sections only) - Dissolved Oxygen (% saturation) - Transparency (estuarine sections only) - Turbidity (NTU) - Electrical Conductivity (µS/CM) (freshwater sections only) - PH (pH units) (freshwater sections only) - Transparency/PAR Attenuation (m) (estuarine sections only) - Suspended Solids (µg/L) - Toxicants in sediments (selected via hazard identification) It is recommended that biological assessments in the river be undertaken at least every 5 years. It is recommended that E.Coli/Enterococci is measured at least 5 times/month
EPA Victoria 49 MERRI RIVER ESTUARY
at regular intervals in the estuary and Lake Pertobe during summer months when primary contact recreation is likely. 4.2 Glenelg Hopkins Catchment Management Authority ensure that all monitoring MOD 17 data is incorporated into the Victorian Water Quality Monitoring Network Database so that it can be accessed by other organisations. 4.3 Relevant stakeholders implement the recommendations in Glenelg Hopkins HIGH 41, 43, 45, Nutrient Management Plan to ensure that nutrient levels in Merri River are 47, 48, 50 reduced. 4.4 EPA should investigate causes of low DO levels in the River. LOW 25, 26 4.5 Glenelg Hopkins Catchment Management Authority should manage any LOW 25, 26 identified causes of reduced DO levels. 4.6 EPA should investigate causes of high EC levels in the River. LOW 30 4.7 Glenelg Hopkins Catchment Management Authority should manage any LOW 30 identified causes of high EC levels. 5 Recommendations – Estuary Inputs (Diffuse Rural) 5.1 Glenelg Hopkins Catchment Management Authority should undertake to HIGH 40 proactively educate farmers about the importance of fencing waterways to ensure that stock cannot gain direct access. 5.2 EPA and Moyne Shire Council staff should implement a proactive programme HIGH 44, 45 with dairy farmers within the catchment to prevent pollution of waterways. 5.3 Department of Primary Industry should educate farmers on best practice LOW 43 nutrient management for dryland agriculture and horticulture.
Environmental Audit 50 MERRI RIVER ESTUARY
6 Recommendations – Estuary Inputs (Diffuse Urban) 6.1 Warrnambool City Council should work with South West Water to determine LOW 55 whether all houses with access to reticulated sewerage are connected. 6.2 Moyne Shire Council (and Warrnambool City Council if necessary) should LOW 57 develop a proactive programme to ensure that septic tanks in the catchment are being maintained in accordance with the Council Septic Tank Permits and the relevant Certificate of Approval. 6.3 Warrnambool City Council should ensure that the outstanding actions in their LOW-MOD 60, 62, 63, stormwater management plan are completed in a timely manner. They should 65, 66, 69- report to the community annually on progress that has been made with respect 77 to implementing the plan. 6.4 Moyne Shire Council and Southern Grampians Shire Council ? should ensure LOW 61 that a stormwater awareness brochure (such as the one produced by Glenelg Hopkins Catchment Management Authority) is distributed to all houses in urban areas within the Merri Catchment. 7 Recommendations – Estuary Inputs (Point Source) 7.1 Nestle should develop a more rigorous process to determine whether LOW 80 condensate is “clean” enough to be disposed of by irrigation. 7.2 Nestle should install the stormwater isolation valve they have ordered and LOW 85 develop a worst –case scenario response plan for a stormwater system incident. 7.3 EPA and Warrnambool Stock Feeds work together to collect sufficient data to HIGH 91
EPA Victoria 51 MERRI RIVER ESTUARY
enable an accurate assessment of the environmental impact from the wastewater treatment operations. This should consider impacts from the wastewater stored in ponds and that disposed of by land irrigation. 7.4 Warrnambool Stock Feeds ensure that their wastewater is analysed at least HIGH 94 monthly as required by the Waste Discharge Licence. 7.5 EPA and Warrnambool Stock Feeds agree on steps to ensure wastewater HIGH 95 irrigation is conducted outside the floodplain of the Merri in the future. 7.6 EPA and Warrnambool Stock Feeds work together to investigate the wastewater MOD 96 storage ponds to ensure there is no risk to the beneficial uses of groundwater. 7.7 EPA and Warrnambool Stock Feeds work together to ensure that wastewater HIGH 95 irrigation is conducted in accordance with EPA Pub 168 as required by the Waste Discharge Licence. In particular the following issues should be addressed: - year round irrigation; - depth to groundwater; - wastewater application rates; and - water budget. 8 Recommendations – Estuary Inputs (Marine) 8.1 Parks Victoria should regularly survey the condition of the mouth of the estuary LOW 105 to monitor accumulation of sand. 9 Recommendations – Water Extractions 9.1 The Western Coastal Board and Department of Sustainability and Environment HIGH 109
Environmental Audit 52 MERRI RIVER ESTUARY
should ensure that the Merri Estuary Coastal Action Plan and Streamflow Management Plan are integrated to ensure that environmental flows for the estuary are provided. 9.2 Southern Rural Water should ensure that the Streamflow Management Plan has HIGH 111 contingencies for periods of drought to ensure environmental flows are protected 9.3 Until an environmental flow study recommends otherwise, Southern Rural VERY HIGH 114 Water should update the irrigation roster to ensure that environmental flows meet Streamflow Management Plan requirements. 9.4 Southern Rural Water should ensure that a winter-fill regime is defined. LOW 115 9.5 Southern Rural Water should proactively update all irrigation licences in LOW 116 accordance with the Streamflow Management Plan. 9.6 Department of Sustainability and Environment and Southern Rural Water MOD 118 should work in partnership to ensure that a study on the contribution and interaction of groundwater and surface water base-flows is undertaken. 9.7 Southern Rural Water should ensure that stock and domestic water use is LOW 113 licensed where required by the Water Act 1989. 9.8 Southern Rural Water should update the Streamflow Management Plan to LOW 120, 121 reflect the new flow monitoring site at Grassmere, replacing the Spring and Drysdale Creek monitoring sites. 10 Recommendations – Physical Modifications to Catchment and Watercourse 10.1 Warrnambool City Council Should conduct proactive inspections to identify MOD 132
EPA Victoria 53 MERRI RIVER ESTUARY
landfilling around the South Warrnambool Wetlands and other low-lying land adjacent to the Merri. 10.2 Warrnambool City Council should ensure that a floodway study is undertaken LOW 134 for all low-lying land adjacent to the Merri. 10.3 Glenelg Hopkins Catchment Management Authority should consider additional HIGH 124 proactive measures to encourage revegetation of the catchment.
Environmental Audit 54 MERRI RIVER ESTUARY
REFERENCES
Australian and New Zealand Environment and Conservation Council, Australian Water Quality Guidelines for Fresh and Marine Waters, November 1992
Australian Water Technologies, Kiaora Biosolids: Flora and Fauna Management Plan. Report to Glenelg- Hopkins Catchment Management Authority February 2001
Connell Wagner for Western Coastal Board, Warrnambool Coastal Action Plan, August 1999.
Denny, S. (1995) “Adaptation of the Riparian, Channel and Environmental (RCE) inventory for small streams, for use in South western Victoria” – honours thesis.
Department of Conservation and Natural Resources, Nutrient Management Strategy for Victorian Inland Waters, 1995
ID&A for Warrnambool City Council, Warrnambool Stormwater Management Plan, Draft Report, September 2001
ID&A for Glenelg-Hopkins Catchment Management Authority, Draft Report Merri River Catchment Restoration Plan, December 2000.
Gerner Consulting Pty Ltd for City of Warrnambool, Warrnambool Foreshore Management Plan, February 1993
Glenelg-Hopkins Catchment Management Authority, Glenelg-Hopkins Nutrient Management Plan, January 2002
Koriblitsas L. for Warrnambool City Council and Glenelg-Hopkins Catchment Management Authority, Russell Creek Environmental and Recreational Study, Deakin University, 2000
McGregor J., The Merri River – an Environmental Audit, Honours research project, Deakin University, Warrnambool, 1996
Moverly J & A Hirst, 1999, Estuarine health assessment using benthic macrofauna. LWRRDC Occasional Paper 18/99 (Urban Subprogram, Report #11)
Pierson, W.L., K. Bishop, D. Van Senden, P.R. Horton, P.R. and C.A. Adamantidis, Environmental Water Requirements to maintain estuarine processes, Environmental Flows Initiative Technical Report Number 3, Commonwealth of Australia, 147 pp., Canberra, 2002.
NLWRA 2002. Australian catchment, river and estuary assessment Volumes 1 & 2. National Land and Water Resources Audit, a program of the Natural Heritage Trust.
Scenic Spectrums Pty Ltd for Warrnambool City Council, Landscape Management Plan for the South Warrnambool Wetlands, September 1996.
EPA Victoria 55 MERRI RIVER ESTUARY
Southern Rural Water, final draft Streamflow Management Plan for the Merri River, September 1998
Southern Rural Water, Merri River Streamflow Management Plan report for year ended 30/6/01, 2001
Draft Central West Victoria Estuaries Coastal Action Plan, December 2001
WECP 2003. Western Estuaries Classification Project. Funded by NHT. Managed through Deakin University, Warrnambool and the Western Coastal Board.21
Yangery Groundwater Supply Protection Area Consultative Committee, November 2000, Yangery Groundwater Supply Protection Area Groundwater Management Plan Draft for Consultation
21 “WCEP” is an interim citation title as the final report is awaiting publication.
Environmental Audit 56 MERRI RIVER ESTUARY
GLOSSARY
Aerobic In the presence of free oxygen. Anaerobic In the absence of free oxygen. Antagonistic Relationships Those in opposition or resistance. Aquifer A subsurface geological structure that may be permeated with water. Beneficial Uses Use of the environment or any element or segment of the environment that is conductive to public benefit, welfare, safety, health or aesthetic enjoyment and which requires protection from the effects of waste discharges, emissions or deposits. Catchment The area of land that drains to a watercourse. Dissolved Oxygen The amount of oxygen dissolved in water. E. Coli Escherichia coli. A bacterium that is found in the gut of warm-blooded animals and is used to indicate faecal contamination. Electrical Conductivity A measure of salinity. Environmental Aspects Elements of an organisation’s activities, products or services that can interact with the environment Environmental Audit A total assessment of the nature and extent of any harm or detriment caused to, or the risk of any possible harm or detriment which may be caused to, any beneficial use made of any segment of the environment by any industrial process or activity, waste, substance (including chemical substance) or noise. Environmental Flow Fresh water flow that is maintained solely for environmental reasons, to maintain the health and biodiversity of a particular water-related entity. Environmental Impacts Changes to the environment, whether adverse or beneficial, wholly or partially resulting from an organisation’s activities, products or
EPA Victoria 57 MERRI RIVER ESTUARY
services. Estuary Partially enclosed coastal body of water characterised by tidal effects and mixing of fresh with seawater. Eutrophication Excessive plant growth (including algae) resulting from nutrient enrichment. Faecal Coliforms Faecal bacteria, the majority of which are E.coli. Fish Ladder Inclined waterway, commonly an artificial channel with stepped pools installed at a dam to allow passage of migratory fish over or around an obstruction. Groundwater Any water contained in or occurring in a geological structure or formation or an artificial landfill. Macroinvertebrate An animal without a backbone large enough to be seen without magnification. Median The middle value of a sample data set arranged in order of magnitude. Nutrients Elements, which are obtained from the soil, water and air that are essential for plant growth including N, P, K, C and a range of trace elements. Objective A level of an indicator or any other property of a water body as specified by the Authority for protection of beneficial uses. Pathogens Organisms capable of causing illness in animals, including human beings and plants. pH A numerical measure of acidity and alkalinity in water or soil. Planning Overlay Additional requirement to a planning zone, which provide for specific development issues or policy matters. Planning Scheme Legal instruments, developed by municipalities under the Planning and Environment Act 1987, that set out policy and requirements for use, development and protection of land.
Environmental Audit 58 MERRI RIVER ESTUARY
Planning Zone Measures in planning schemes, which determine the permissible uses of land of a given type or in a given area. Pollution A state in which water, land or air is changed so as to be: a) noxious or poisonous; b) harmful or potentially harmful to human beings; c) poisonous, harmful or potentially harmful to wildlife; d) poisonous, harmful or potentially harmful to plants; or detrimental to any beneficial use made of water, land or air. Rendering Operation Extraction of oil, lard, tallow etc from fatty animal substances. Riparian Inhabiting or situated on a river or stream bank or where vegetation interacts with surface waters. Runoff Water that drains off the surface after irrigation or rain. Segment In relation to the environment means any portion or portions of the environment, expressed in terms of volume, space, area, quality or time or any combination of these. Sewerage Works for the collection, treatment and disposal of wastewater. Total Kjeldahl Nitrogen Combination of ammonia and organic nitrogen. Total Nitrogen The sum concentration of bioavailable (dissolved) and particulate forms of inorganic and organic nitrogen. It is a combination of ammonia, organic nitrogen, nitrate and nitrite. Total Phosphorous The sum concentration of dissolved and particulate forms of inorganic and organic phosphorous. Toxicant Substance that is poisonous to living things.
EPA Victoria 59 MERRI RIVER ESTUARY
Stormwater Runoff from land during and following rain. Stormwater removes accumulated material including litter, soil, nutrients, pathogens, chemicals, pesticides, oils and grease. Synergistic Relationships Complimentary. Wastewater The used water of a community or industry, containing dissolved and suspended matter. Water Sensitive Urban Design The integration of urban planning and development with the management, protection and conservation of the water cycle as a whole. Waterwatch A national community water monitoring program funded by the Federal Government’s National Heritage Trust and administered by Environment Australia. Wetland Land where saturation by water is the dominant factor for soil type and plant/animal communities.
Environmental Audit 60 MerbeinMildura Red Cliffs APPENDIX 1: MAP SHOWING LOCATION OF THE MERRI RIVER CATCHMENT Robinvale
Ouyen
Swan Hill
Kerang Cohuna Cobram Rutherglen Echuca Numurkah Wodonga Warracknabeal Nhill RochesterKyabram WangarattaBeechworth Dimboola Tatura Benalla St Arnaud Mooroopna Myrtleford Horsham Bendigo Euroa Bright Mount Beauty Stawell MaryboroughCastlemaine Seymour Mansfield Broadford Alexandra Ararat Kyneton Creswick WoodendWallan Casterton Ballarat Gisborne Hamilton Millgrove Orbost Melbourne Bairnsdale Bacchus Marsh Warburton Lara HeyfieldMaffra Paynesville Sale Drouin Moe Terang Leopold Portland Colac Torquay Hastings WarragulMorwell Port Fairy Camperdown Anglesea Cowes Leongatha Warrnambool Yarram WonthaggiInverloch Southern Grampians Shire Council
Legend Major Roads Purdeet Water Courses Local Government Boundary Merri River Catchment
Minhamite
Minjah
Lovel
Woolsthorpe
Ballangeich North Moyne Shire Council
Winslow Cooramook
Grassmere Yarpturk Purnim Mailer Flat Purnim West Souther Cross Woodfood Grassmere Junction Illowa Bushfield Yangery
Dennington Warrnambool
Warrnambool City Council
051020 Kilometers APPENDIX 3: AERIAL PHOTO OF THE MERRI ESTUARY
Bromfield St Weir
Confluence of Race Track Russell’s Creek and Merri River Nestle
Warrnambool Stock Feeds Irrigation Estuarine Section Boundary Area (Approx)
Lake Pertobe Warrnambool Golf Course
Warrnambool Stock Feeds Warrnambool Wastewater Treatment Plant Original River Path Trotting Track Previous Site of Rifle Range Estuary Mouth
Aerial photography copyright Qasco Vic Image © 2003 APPENDIX 4: MAP SHOWING PLANNING ZONES SURROUNDING THE LOWER SECTIONS OF THE MERRI RIVER APPENDIX 5: MERRI RIVER VICTORIAN WATER QUALITY MONITORING NETWORK DATA
Nitrates and DO DO EC Nitrites TKN TN TP SS TDS TOC Turbidity Date (mg/L) (%sat) (uS/cm) (mg/L) (mg/L) (mg/L) (mg/L) pH (mg/L) (mg/L) (mg/L) (NTU) 11/12/75 8.6 87.5 1400 7.5 2/4/76 2200 7.5 12/16/76 7.6 80.8 2200 7.6 2/22/77 6 63.9 2500 7.4 0.5 3/23/77 10 100 2500 7.7 0.3 4/21/77 7.5 75.1 2800 7.9 3 5/17/77 9.5 87.1 2700 7.1 1 6/22/77 9.6 85.4 1400 7.9 18 7/19/77 9 76.4 1500 8 14 8/23/77 9.1 82 1600 7.8 27 9/20/77 9.4 92.1 2600 8.2 6 10/19/77 9 89.2 2400 8.1 4 11/21/77 11 114.7 2400 0.27 0.23 0.5 8.3 2 0.9 12/29/77 8 85.6 2700 8.2 1.5 2/1/78 9.5 100.1 3000 7.9 1.1 3/6/78 8.6 89.7 2400 8.3 1 1 4/4/78 9 89.9 2300 7.9 1.2 3/6/78 0.47 0.41 0.88 0.045 1420 5/3/78 7.3 71.6 2900 7.9 1 6/6/78 8.6 80.4 2000 0.56 0.4 0.96 0.049 7.8 5 2300 1.4 7/4/78 10.2 91.2 2400 1.6 8/1/78 9.8 85.1 1200 6.7 17 9/11/78 9.1 89.2 1900 0.082 0.8 0.882 0.004 7.8 10 1100 10 2.1 10/17/78 10 102 2200 8.1 1.9 11/7/78 8.4 89.3 2000 7.8 5.4 12/12/78 8.6 91.4 2100 1.3 1/9/79 8.6 95.3 2400 0.8 2/13/79 8.3 92 2400 0.29 0.45 0.74 0.032 7.9 1 1600 12 1 3/20/79 7.9 84.1 2500 8.1 0.7 4/19/79 8.6 85.9 2800 7.7 1 5/7/79 9.4 90.1 2700 1.1 0.55 1.65 0.039 7.9 2 1700 13 0.5 7/10/79 9.8 89.3 3400 8 0.4 8/6/79 11.4 98.5 91 6.8 4 8/7/79 10.5 94.1 2900 0.62 0.3 0.92 0.012 8.1 3 1700 3 1.2 9/11/79 9.9 100.5 3000 8.6 1.2 10/10/79 8.8 85.3 660 7.3 35 11/5/79 7.8 82.9 2100 0.89 0.75 1.64 0.097 7 1600 8 1 12/4/79 7.4 80.4 2600 7.9 0.7 1/8/80 8.6 92.6 2400 8 0.5 2/4/80 8.2 86.2 2500 0.2 0.3 0.5 0.037 8 3 1670 4 0.8 3/4/80 5.6 58.8 2400 7.8 1.3 4/10/80 7.5 74.1 2300 7.5 1.3 5/6/80 8 78.2 2700 0.69 0.45 1.14 0.058 2 2000 4 0.4 6/3/80 8.8 81.5 3100 7.7 1.8 7/8/80 8.9 80.1 1900 7.9 16 8/4/80 10.7 95.7 2500 0.38 0.9 1.28 0.062 8.4 6 1500 9 9/10/80 10.1 82.8 2300 8.3 10/7/80 2200 8.1 11/3/80 10 97.7 2500 0.6 0.55 1.15 0.058 8.2 4 1500 11 1.3 12/2/80 2600 7.8 0.5 Nitrates and DO DO EC Nitrites TKN TN TP SS TDS TOC Turbidity Date (mg/L) (%sat) (uS/cm) (mg/L) (mg/L) (mg/L) (mg/L) pH (mg/L) (mg/L) (mg/L) (NTU) 1/6/81 6.1 67.3 2400 8.1 1.1 2/9/81 2600 0.44 0.5 0.94 0.07 7.9 1 1600 4 0.5 3/17/81 8.4 86.1 2700 7.8 0.8 4/7/81 5.4 56.4 2700 7.5 0.5 5/11/81 7.9 74.7 3100 0.66 0.35 1.01 0.044 8.4 1 1700 5 0.6 6/10/81 9.6 85.4 3700 8.1 0.7 7/7/81 9.7 85.4 3900 8 1.8 8/12/81 9.4 84.5 1100 1 2 3 0.153 86 720 16 9/8/81 1800 10/15/81 2600 1.3 11/11/81 2600 0.48 0.4 0.88 0.052 2 1700 5 0.5 12/8/81 2300 8.2 1.1 1/5/82 3100 0.5 2/8/82 2300 0.6 2/15/82 0.28 0.5 0.78 2 1600 4 3/17/82 5 53.8 2400 0.8 4/6/82 8 80 2500 1.5 5/10/82 7.6 71.2 2600 0.54 0.6 1.14 0.041 2 1800 2 0.5 6/10/82 10.1 85.7 3200 0.3 7/6/82 10.6 91.7 3300 0.5 8/9/82 9.8 85.8 3300 0.5 0.35 0.85 0.03 7 2300 3 0.6 9/8/82 9.9 90.8 2900 7.8 0.7 10/6/82 8.9 85.8 3100 7.8 0.6 11/15/82 8.4 86.1 2700 0.35 0.3 0.65 0.064 7.2 3 1700 2 0.5 12/7/82 7.6 76.2 2500 7.5 0.5 1/12/83 6.4 64.7 2400 0.8 2/3/83 6.7 72.9 2300 7.9 1.5 3/7/83 3.9 43.8 2100 0.18 0.4 0.58 0.123 7.8 2 1700 2 0.5 5/10/83 7.4 72.3 2200 7.2 1.5 6/8/83 9.2 81.7 2300 0.9 1.2 2.1 0.063 7.4 14 1400 16 5.6 7/4/83 9.4 83.7 540 7.6 40 8/2/83 10.5 95.8 1700 8 13 9/14/83 10.3 88.4 280 7.3 71 9/20/83 8.6 81.8 800 0.39 1.4 1.79 0.102 7.7 22 520 19 25 10/6/83 8.5 82.2 1700 0.59 0.7 1.29 0.021 7.9 7.1 11/7/83 8.4 83 2200 7.9 11 12/6/83 6.4 66.1 1700 7.7 4 1200 9 2 1/10/84 7.6 82.5 2400 7.9 2 2/7/84 6.4 69.5 2300 7.8 1.9 3/6/84 8.5 91.8 2400 0.64 0.35 0.99 0.074 7.8 4 1800 3 1 4/4/84 8 79 3500 7.8 1.3 5/7/84 9.3 86.2 3200 7.8 0.6 6/5/84 9 83.6 3200 8.4 1.2 7/2/84 9.7 86.1 3100 0.49 0.3 0.79 0.027 7.9 3 2200 3 1.1 8/7/84 9 83.6 2600 7.9 1.5 9/12/84 9 80.4 1300 0.32 1.8 2.12 0.134 7.6 24 840 20 24 10/3/84 8.1 77.6 1200 7.6 9 11/8/84 8.4 87.5 2300 7.8 1.7 12/3/84 9.5 99.1 2400 8 0.7 12/17/84 8.1 85.3 2400 0.39 0.4 0.79 0.027 7.8 3 1500 4 1 1/7/85 7.8 80.5 2500 0.33 0.35 0.68 0.03 7.8 2 1300 4 0.5 2/5/85 6.9 74.3 2400 6.9 1.1 Nitrates and DO DO EC Nitrites TKN TN TP SS TDS TOC Turbidity Date (mg/L) (%sat) (uS/cm) (mg/L) (mg/L) (mg/L) (mg/L) pH (mg/L) (mg/L) (mg/L) (NTU) 3/4/85 8 82.6 2400 0.34 0.4 0.74 0.036 8.2 1 1600 2 0.7 4/2/85 7.4 72.3 2100 3.7 5/6/85 8.5 82.5 3000 0.9 6/3/85 9 79.8 3100 0.52 0.3 0.82 0.033 1 1700 26 1.4 7/1/85 9.2 84.9 2100 7.1 8/5/85 9.4 82.7 1500 12 9/3/85 9.5 82.7 1100 0.115 2.4 2.515 0.137 59 550 6 36 10/7/85 9.7 98 2400 7.8 1.5 11/4/85 9.6 98.7 2500 8.1 1 12/2/85 9.2 98 2200 0.38 0.5 0.88 0.052 8.8 2 1200 3 1.2 1/7/86 8.6 95 2100 7.8 1.4 2/3/86 9.2 99.7 2400 7.8 0.7 3/3/86 9.2 98.3 2400 0.29 0.25 0.54 0.033 7.9 1 1400 7 0.9 4/9/86 7.6 75.2 2500 7.6 0.8 5/13/86 9.7 95.2 3100 8 1.2 6/2/86 10 94.5 2900 0.53 0.15 0.68 0.049 2 2000 18 1.5 7/8/86 10.5 90.1 1200 7.8 15 8/5/86 10.1 91.4 1400 7.8 14 9/1/86 9.2 83.8 1400 0.33 0.7 1.03 0.106 7.2 25 8905 22 10/1/86 8.7 89.5 1600 7.6 0.6 11/4/86 1400 7.8 5.6 12/2/86 2300 0.4 0.45 0.85 0.019 7.9 2 1500 4 0.7 1/6/87 7.7 78.1 2200 3.2 2/3/87 9.8 103.2 2400 7.7 0.7 3/2/87 11.4 118.4 2400 0.29 0.15 0.44 0.021 8.3 1 1500 11 0.7 4/8/87 7.2 75.2 2900 0.8 5/5/87 9.4 91.2 2900 0.7 6/2/87 0.7 0.8 1.5 0.101 2 1300 12 7/6/87 10 89 2400 7.9 2.7 8/3/87 11.1 97 2500 8 2.9 9/7/87 10 91.4 2100 0.23 0.95 1.18 0.046 7.9 4 1300 4 7.9 10/6/87 8.7 83.4 2700 8.1 3 11/3/87 7.5 83.2 2700 8.1 1.2 12/2/87 8.7 89.7 2300 0.16 0.6 0.76 0.041 7.8 1 1300 2 1.7 1/5/88 6.4 68.9 2800 7.8 1.1 2/2/88 7.2 79.8 2500 7.8 1 3/2/88 4.4 46.8 2400 0.28 0.3 0.58 0.12 7.6 5 1900 2 1.2 4/13/88 7 67.7 2400 8.2 3.5 5/3/88 5.6 55.6 2600 7.9 1 6/7/88 8.6 79.9 3100 0.63 0.3 0.93 0.05 8.1 1 1 7/5/88 10.7 93.9 3300 8.1 1.7 8/2/88 9.8 92.3 3600 7.9 2.2 9/14/88 10.5 94.4 1000 0.16 2.1 2.26 0.16 7.7 44 680 5 53 10/4/88 7.8 77.9 2200 8.2 7.2 11/2/88 9.7 107.6 2700 7.9 1.5 12/6/88 8.4 89.5 2600 0.15 0.6 0.75 0.031 8 3 1900 2 1 1/4/89 8 86.9 2500 8.3 2.7 2/8/89 8.5 94.1 2300 7.9 2.1 3/2/89 8.9 101.5 2400 0.062 0.3 0.362 0.052 7.9 31900 4 1.5 4/4/89 8 85.2 2500 7.9 1.1 5/16/89 9.6 89.2 3100 7.9 1.1 6/7/89 10.6 92 3400 0.43 0.4 0.83 0.034 8 1 2500 19 1.7 Nitrates and DO DO EC Nitrites TKN TN TP SS TDS TOC Turbidity Date (mg/L) (%sat) (uS/cm) (mg/L) (mg/L) (mg/L) (mg/L) pH (mg/L) (mg/L) (mg/L) (NTU) 7/11/89 11.1 93.9 3000 8.1 2.7 8/9/89 10.6 88.6 840 7.6 67 9/5/89 8.9 80.9 910 0.4 1.7 2.1 0.062 7.7 16 600 5 25 10/3/89 9.2 85.9 1900 7.7 8 11/8/89 7.8 78.7 1900 7.9 4.7 12/5/89 9.4 98 2300 0.31 0.6 0.91 0.036 8 2 1500 3 1.8 1/3/90 9.4 100 2400 7.9 1.4 2/6/90 7.4 71.6 2500 7.9 1.3 3/6/90 7.7 82 2600 0.44 0.6 1.04 0.089 8 4 2100 2.4 4/4/90 10.4 104.1 2700 8 1.3 5/9/9010.696.2 3000 7.6 1.2 6/5/90 10.4 93.3 3100 0.43 0.4 0.83 0.028 8.1 2 2000 1.3 7/3/90 10.1 85.5 3200 8.3 3.4
P10 7.2 71.67 1400 0.16 0.3 0.58 0.026 7.5 1 816 2 0.5 P25 7.975 80.33 2200 0.29 0.35 0.755 0.033 7.8 2 1300 3 0.8 P50 8.9 85.65 2400 0.4 0.45 0.882 0.049 7.9 3 1600 5 1.3 P75 9.7 92 2700 0.55 0.7 1.165 0.07 8 5 1800 11 2.925 P90 10.4 98.27 3100 0.69 1.4 2.1 0.121 8.2 22 2020 17.2 14
MAX 11.4 118.4 3900 1.1 2.4 3 0.16 8.8 86 2500 26 71 MIN 3.9 43.8 91 0.062 0.15 0.362 0.004 6.7 1 520 2 0.3 APPENDIX 6: EPA WATER QUALITY MONITORING DATA
DO (%sat) DO (%sat) pH pH TKN (mg/L) TKN (mg/L) TP (mg/L) TP (mg/L) Date Warrnambool Woodford Warrnambool Woodford Warrnambool Woodford Warrnambool Woodford 22/09/1999 8.6 8.0 2.0 0.2 7.8 4.1 0.7 27/11/2000 76.2 98.1 7.94 8.3 1.6 1.6 0.056 0.073 72.2 7.92 2 0.12 30/03/2000 86.4 21.3 8.09 7.66 0.91 0.64 0.066 0.17 35.4 7.94 2.1 0.23 19/03/2001 103.9 71.2 8.31 7.9 1.2 0.59 0.11 0.089 102.4 8.31 1.4 0.16 15/10/2001 108.5 82.5 8.11 7.86 1.3 1.4 0.13 0.1 107.5 7.95 1.4 0.14 average 86.5625 68.275 8.07125 7.93 1.48875 1.0575 0.1265 0.108 maximum 108.5 98.1 8.31 8.3 2.1 1.6 0.23 0.17 minimum 35.4 21.3 7.92 7.66 0.91 0.59 0.056 0.073 APPENDIX 7 LONGITUDINAL PROFILE OF NUTRIENT LEVELS IN RUSSELL’S CREEK (KOROBLITSAS, 2000)
NB. Sampling Site 1 is the furthest upstream and site 6 is the furthest downstream
Nitrogen Levels in Russell's Creek (Koroblitsas, 2000)
5
4.5
4
3.5
3
2.5
2 Total Nitrogen (mg/L) 1.5
1
0.5
0 123456 Sampling Site
Phosphorous Levels in Russell's Creek (Koroblitsas, 2000)
0.35
0.3
0.25 )
0.2
0.15
Total Phosphorous (mg/L Total Phosphorous 0.1
0.05
0 123456 Sampling Site
APPENDIX 8: AVERAGE MONTHLY RAINFALL AT WARRNMABOOL AIRPORT
120
100
80
Average 60 2002 Rainfall (mm)
40
20
0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Month APPENDIX 9: SUMMARY OF MERRI RIVER IRRIGATION ROSTER
Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 Stage 6 Stage 7 Stage 8 Stage 9 Increase Daily Average 12ML – one stage; 10ML go to stage 7; 8ML – immediate BAN 10ML – one stage; 8ML – BAN 5-Day Average 12ML – go to stage 7 immediately; 10ML – immediate BAN 12ML – one stage, 10ML - BAN Ease Daily Average 14ML – one stage 12ML – one stage