Water Quality and Stream Condition on King Island, 2004 - 2008

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

This report has been produced by Cradle Coast Natural Resource Management and the King Island Natural Resource Management Group to further natural resource management goals and objectives in the Cradle Coast Region. Maps, photos and other components of this report remain the joint property of Cradle Coast NRM and King Island NRM Group. All site photographs were taken by Helen Strickland.

This report was written by Debbie Searle, through the Launceston Environment Centre, 1/04/2010.

Peer review by Toni Furlonge.

This report should not be considered as a guide to the suitability of water for drinking, domestic, recreational or agricultural purposes.

Acknowledgments:

We gratefully acknowledge the funding assistance for this project provided by the Australian Government’s Natural Heritage Trust and Caring for our Country programs.

The following organisations are thanked for their support and contribution to the community water monitoring program on King Island: Cradle Coast Natural Resource Management Committee; King Island Natural Resource Management Group; North West Waterwatch Inc.; King Island Council, King Island Dairies and the Department of Primary Industries, Parks, Water and the Environment.

Thanks also to Katie Brown, Bronwyn Graham, Ken Baker, Eva Finzel, Helen Strickland and the many community volunteers, whose interest, enthusiasm and activities contribute to the increased knowledge and improved management of King Island’s natural resources.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Contents Executive Summary ...... 4 1. Introduction ...... 8 2. Cradle Coast NRM ...... 9 3. King Island NRM Group ...... 10 4. King Island ...... 10 5. The Water Monitoring Program ...... 12 6. Assessing Water Quality ...... 13 7. Assessing Stream Condition ...... 16 8. The Sites ...... 19 Sea Elephant River at Bicentennial Road ...... 19 Fraser River at Fraser Road ...... 23 Yellow Rock River at North Yellow Rock Road ...... 27 Porky Creek at North Road ...... 31 Grassy River at Grahams Road ...... 35 Egg Lagoon Creek at Mansons Road ...... 39 Seal River at Seal River Road ...... 43 Ettrick River at old DPIW Monitoring Station ...... 47 Yarra Creek at Millwood Road ...... 51 Lake Flannigan ...... 55 Lake Flannigan Drain at Wickham Road ...... 59 9. Recommendations ...... 61 Appendix 1: Site Locations ...... 62 Appendix 2: Site Characteristics for the AUSRIVAS model ...... 62 Appendix 3: Water Quality Parameters ...... 63 References ...... 65

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Executive Summary

This report presents the results of a water monitoring program established by Cradle Coast Natural Resource Management and the King Island Natural Resource Management Group, with the assistance of North West Waterwatch Inc. The program was part of the Priority Project “A Water Quality Monitoring Program and Reporting Framework for the Cradle Coast Region” established with the assistance of the Commonwealth Natural Heritage Trust Fund.

King Island is approximately 1,100 km2 in area and is located in the west of Bass Strait. It is generally characterized by low relief, with distinct physiographic areas. These differing areas have caused the development of streams of distinctly different characteristics, behaviour and management. This variability needs to be kept in mind when reading this report.

Eleven sites were monitored, nine of those monthly from November 2004 until the end of 2008. One site was monitored in 2005 and one from 2006 to 2008. Water quality parameters measured were electrical conductivity (salinity), pH, temperature, turbidity, dissolved oxygen, and phosphate. Samples were taken at nine sites and tested for total nitrogen and total phosphorus; intermittently in 2005, 2006 and 2007 and quarterly in 2008. All sampling, measurement and data management were conducted in accordance with national and state standards and were subject to regular and rigorous quality controls. No monitoring of flow quantities was carried out, however anecdotal evidence was recorded, for example, no perceptible flow, low flow, water level high.

Photographic evidence and information on the state of riparian habitat at each site was recorded. In addition, AUSRIVAS rapid biological assessments were undertaken at eight of the sites in 2005 and 2006.

In this report the 2007 and the 2008 results have been compared to ANZECC guidelines to gain an overall picture of water quality across the island. Due to the low lying nature of King Island, this report has used the lowland river values for streams. These are the most relevant benchmarks available but it should be noted that they were developed for much larger rivers.

Water quality data collected on King Island has been analysed and results from 2004, 2005 and 2006 have been used to generate local site-specific current-status trigger values where possible. These local trigger values are calculated from the 80th percentiles of the data (20th percentiles for pH as well). In this report these trigger values have been used as benchmarks to assess data from 2007 and 2008.

The development of local trigger values for turbidity fulfils part of Management Action Target Water 3, “Use historic data to establish trigger values for …turbidity in selected catchments….”

The development of the local trigger values for turbidity will allow the tracking of progress towards Resource Condition Target Water 2, “No increasing trend from 2006 trigger levels in turbidity … at all monitored sites: by 2010. “

The development of local trigger values for electrical conductivity goes part way towards assessing progress towards Resource Condition Target Water 4, “Surface water salt loads maintained below established trigger levels in key catchments including King Island: by 2015.”

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Local Site-Specific Current-Status Trigger Values Site Code Waterbody EC pH pH Temp- Turbidity Dissolved Phos- (µS/cm) 20th 80th erature (FTU) Oxygen phate (oC) (mg/L) (ppm) KINGIS01 Sea Elephant River 675 5.93 6.66 17.0 63 7.14 0.60 KINGIS04 Porky Creek 2556 7.25 7.78 16.4 22 6.54 1.11 KINGIS05 Grassy River 439 6.70 6.99 15.5 79 9.70 0.76 KINGIS06 Egg Lagoon Creek 6362 7.37 7.72 18.2 59 9.32 0.35 KINGIS07 Seal River 21140 6.58 7.19 16.0 133 4.11 0.50 KINGIS09 Ettrick River 799 7.86 8.13 15.2 65 10.80 0.32 KINGIS11 Yarra Creek 458 6.58 7.05 15.1 66 9.60 1.29

AUSRIVAS rapid biological assessments were carried out at eight of the sites in 2005 and 2006. These results have been analysed, where possible, using the AUSRIVAS predictive model to calculate benchmark ratings.

The calculation of AUSRIVAS benchmark ratings for seven sites on King Island fulfils part of Management Action Target Water 1, “Establish river condition benchmarks in priority (CFEV) catchments/areas: by 2009.”

River Condition Benchmarks for King Island Site Code Waterbody Season and Habitat O/E SCORE Benchmark Rating

KINGIS01 Sea Elephant River Spring 2005 Edge 0.41 C

KINGIS02 Fraser River Spring 2005 Edge 0.69 B

KINGIS04 Porky Creek Spring 2005 Edge 0.43 C Outside experience KINGIS05 Grassy River Not available Not available of model KINGIS06 Egg Lagoon Creek Spring 2005 Edge 0.49 C

KINGIS07 Seal River Spring 2005 Edge 0.62 B Combined Spring 2005, KINGIS09 Ettrick River 0.63 B Autumn 2006 Riffle Combined Autumn and KINGIS11 Yarra Creek 0.73 B Spring 2005 Riffle

Note: In the development of the predictive model for Tasmania, no reference or test sites were chosen from King Island. This report has still used the model, as it is the best tool available for analysing the information that has been collected.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Summary of Water Quality Results

Many of the samples taken across the island exceeded the ANZECC guidelines for electrical conductivity, turbidity, phosphate, total phosphorus and total nitrogen. This can be partly attributed to the very low flows at many sites during drier months.

Electrical conductivity readings across the island have shown the influence of the soil types in the surrounding catchments. Sea Elephant River, Fraser River, Grassy River, Ettrick River and Yarra Creek have all had levels within the ANZECC guidelines while Yellow Rock River, Porky Creek, Egg Lagoon Creek and the Seal River have had high levels reflecting the presence of highly saline soils in the latter catchments. The high levels at the Seal River in late summer and autumn also reflect the tidal influence at this site.

At Porky Creek, Sea Elephant River and the Ettrick River, electrical conductivity levels in both 2007 and 2008 have regularly exceeded the local trigger values calculated from 2005 and 2006 data. This may be due to the low rainfalls and low flows experienced in 2007 and 2008. At Egg Lagoon Creek and the Grassy River, electrical conductivity levels in both 2007 and 2008 have been very similar to the local trigger values calculated from 2005 and 2006 data. At the Yarra River the electrical conductivity level in 2007 is slightly higher than the local trigger value calculated from 2005 and 2006 data, while the level from 2008 is very similar to it. pH values have generally been within the ANZECC guideline values at all of the sites except for Lake Flannigan which tended to be alkaline.

Temperature readings have shown seasonal variation at all sites.

Turbidity levels at the majority of sites have regularly exceeded the ANZECC guidelines, highlighting that excess silt and sediments in waterways may be a threat to water quality across the island. Peaks in turbidity readings have occurred during times of high flow levels, which may be partly due to run-off and erosion. Peaks have also occurred during times of low flows which may be partly due to instream plant cover, algal growth, tannin and fine leaf material in the water.

Dissolved oxygen readings were recorded for eight sites and these have shown variation at all sites. This may be influenced by flow level, time of day, water temperature, water chemistry and the level of aquatic plant and algal growth. Interpretation of each result is very complex and so these results are not discussed further in this report.

Phosphate readings were recorded for all but one site. The majority of readings exceeded the ANZECC guidelines. Peaks in phosphate readings mirrored peaks in turbidity at a number of sites and may be partly due to run-off and erosion associated with rain events and high flow levels.

Total phosphorus and total nitrogen readings were recorded for all but two sites. The majority of readings exceeded the ANZECC guidelines. The highest reading for total phosphorus was recorded at Porky Creek, with a reading 14 times the ANZECC value, while the highest reading for total nitrogen was recorded at Egg Lagoon Creek, 26 times the ANZECC value. High phosphate, nitrogen and phosphorus readings highlight excess nutrients in waterways as a threat to water quality across the island. The small size and intermittent flow of streams on King Island makes them particularly vulnerable to fluctuations in nutrient levels. At many of the

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008 sites, these excess nutrients appear to be contributing to prolific growth of algae and/or aquatic plants. The Ettrick and Seal rivers show the least visual evidence of excess nutrients.

Recommendations for Monitoring

1. It is recommended that a monthly water quality monitoring program continue, targeting current sites in priority catchments. This will generate data useful for the management of water resources on King Island. This data could be used to assess progress towards Management Action and Resource Condition Targets and allow long term trends in water quality to be determined into the future.

Priority catchments are the Sea Elephant River which discharges into the Lavinia State Reserve, a Ramsar wetland; Grassy River which supplies drinking water to Grassy township; Ettrick River which is representative of a stream with a natural riffle, pool and run sequence; Porky Creek, whose surrounding land use includes an abattoir and cheese factory; and Yellow Rock River which contains important habitat for Orange Bellied Parrots.

Lesser priorities for monitoring are Fraser River, Yarra Creek and Egg Lagoon Creek. The current site on Seal River appears to be tidally influenced; therefore continuation of monitoring in this catchment would be dependent on finding a suitable site upstream of the tidal influence. The Lake Flannigan Drain tends to dry up during drier months so it is not recommended that monitoring continues in that waterway.

2. It would also be useful to locate and monitor at relatively unimpacted sites in priority catchments if these are available and accessible. These could act as reference sites for other impacted test sites and provide comparative information to further understand catchment and land-use impacts.

3. The adoption of the Tasmanian River Condition Index for key catchments could be considered if resources allow. This would provide a more integrated measure of river health.

4. The development of Water Quality Targets in key catchments is recommended for long-term management of water resources on King Island.

Recommendations for On-ground Works

Work has been done in the past to fence off riparian vegetation along waterways. Extending the current fencing is a high priority to improve water quality on King Island. This will exclude stock, reducing bank erosion and the fouling of waterways.

Fencing off and allowing riparian vegetation to grow will provide shade for rivers, allowing for higher oxygen levels (more oxygen dissolves in cool water than in warm water) and moderating temperature ranges. Riparian vegetation along waterways will also act as a filter, reducing the amounts of animal manure, fertilisers and other pollutants entering the waterways. Riparian vegetation will act as shelter belts for stock, pasture and native fauna.

The continued adoption of best practice land management techniques by landholders across the island will improve water quality through limiting the entry of sediment and nutrients into waterways.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

1. Introduction

This report, published by the Cradle Coast Natural Resource Management Committee (Cradle Coast NRM) and the King Island Natural Resource Management Group (King Island NRM Group), discusses the results of water quality and stream condition monitoring on King Island from late 2004 to the end of 2008. It is intended to support the monitoring, evaluation, reporting and improvement of natural assets on King Island.

A water monitoring program was established in 2004 by Cradle Coast NRM and King Island NRM Group with the assistance of North West Waterwatch Inc. (NWWW). The program was part of the Priority Project “A Water Quality Monitoring Program and Reporting Framework for the Cradle Coast Region”, established with the assistance of the Commonwealth Natural Heritage Trust Fund and continued through Regional Investment Programs One and Two.

Water quality data has been analysed and results from November 2004 to December 2006 have been used to generate local site-specific current-status trigger values. These local trigger values can be used as a measure of the water quality characteristics of waterways on King Island during that period and can act as benchmarks against which levels from 2007 and 2008 can be compared. These local trigger values will also allow long term trends in water quality to be determined into the future.

This report will contribute to the achievement of sustainable communities by fostering an understanding of NRM issues and the state of surface water resources in King Island. Cradle Coast NRM and King Island NRM Group support community involvement in water quality monitoring as a successful way of encouraging community awareness and participation in actions to improve the health of rivers and wetlands.

Cradle Coast NRM, in partnership with DPIPWE, has successfully introduced a Quality Assurance and Quality Control (QA/QC) and data coding system for community monitoring. Community members collect high quality, consistent and accurate data which can be included in the state database and used to assist NRM planning, monitoring and evaluation.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

2. Cradle Coast NRM

Cradle Coast NRM is one of the three Natural Resource Management bodies in Tasmania. Cradle Coast NRM operates under the Cradle Coast Authority and is the regional, non-regulatory body undertaking the strategic management of the region’s natural resources.

Cradle Coast NRM is an organisation that is actively assisting communities in north-west Tasmania to manage and improve their natural resources to ensure a healthy future for the region. Cradle Coast NRM is a not-for- profit organisation which fosters collaborative management of the region’s natural resources by government, industry, private enterprise, traditional owners and community groups.

The Cradle Coast NRM vision for the region is: “Vibrant communities committed to protecting natural resources and actively involved in managing the resources for their environmental, social and economic benefits and values, to ensure a sustainable future for our region.” (Cradle Coast NRM, 2005).

The Cradle Coast NRM goals for water are: “To manage the use of water by maintaining a sustainable balance between social, environmental and economic values” and “To foster an integrated ‘whole of catchment’ approach to water management planning.” (Cradle Coast NRM, 2005).

The Cradle Coast NRM Strategy has a number of Management Action Targets, Resource Condition Targets and Aspirational Targets. This report will specifically relate to some of these targets as listed below, but will also inform other Resource Condition Targets. The health of the Region’s other natural assets of biodiversity, land and atmosphere as well as coastal, estuarine and marine environments is closely linked to the condition of water. Targets from the regional strategy relating to these assets may also be affected by the management of water.

Table 1. Relevant Management Action Targets and Resource Condition Targets relating to water from the Cradle Coast NRM Regional Strategy. Code Target MAT W1 Establish river condition benchmarks in priority catchments/areas: by 2009 Use historic data to establish trigger values for …turbidity in selected catchments…. MATW3

RCTW1 River condition in areas of agricultural land use maintained or improved from 2010 benchmarks. RCTW2 No increasing trend from 2006 trigger levels in turbidity … at all monitored sites: by 2010. Surface water salt loads maintained below established trigger levels in key catchments RCTW3 including King Island: by 2015.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

3. King Island NRM Group

The King Island Natural Resource Management Group Inc. (King Island NRM Group) was formed in 1996 with representatives from King Island Council, industry, landcare and other community groups.

The group’s objective is: “To promote co-ordinated and integrated management of natural resources, which will contribute to the economic and environmental sustainability of King Island.” This is achieved by planning and implementing a range of environmental projects which support the management of the island’s natural resources.

The aims of the Water Monitoring Program are: 1. To collect sound scientific data on the quality of King Island's key waterways. 2. To inform and train the King Island community in "caring for waterways". 3. To establish and maintain an island wide community-based water quality program.

More information on the King Island NRM Group can be found at: http://www.kingisland.net.au/~naturalresources/

4. King Island

King Island is located in the west of Bass Strait. It is approximately 1,100 km2 in area and is generally flat with the highest point being 143 m above sea level. It experiences a mild maritime climate, receiving predominantly winter rainfall of between 675 and 1050 mm annually. Despite King Island’s high rainfall the streams are quite small and many are intermittent. Some surface reaches are particularly prone to drying in the summer, whilst others continue to run (NWWW, 2006).

Generally characterized by low relief, there are distinct physiographic areas: the plateau country, the plains, swamps and lagoons and the dune formations. These differing areas have caused the development of streams of distinctly different characteristics, behaviour and management (NWWW, 2006). This variability needs to be kept in mind when reading this report.

King Island has been extensively cleared for agricultural development and some river systems are significantly degraded through extensive modification of the natural system. Soldier settlements were established on the island after both the world wars. A total of 50 soldier settler farms were established after World War I and another 161 farms were developed across the island at Egg Lagoon, Reekara, Yarra Creek, Pegarah and near Mount Stanley after World War II (NWWW, 2006).

Large lagoon systems that once existed in the north of the Island have been largely modified through extensive networks of drains. Some long-time residents believe that drainage, together with extensive clearing, has significantly reduced the duration of flow in the island’s seasonal waterways. Some land managers are undertaking activities that protect and/or rehabilitate riparian vegetation and wetlands (NWWW, 2006). There has been a great deal of effort in some catchments, for example, the Fraser, directed to fencing off riparian vegetation to exclude stock.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 1: Map of King Island showing major waterways, towns and monitoring sites.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

5. The Water Monitoring Program

This report presents the results of a water monitoring program established by Cradle Coast NRM and the King Island Natural Resource Management Group with the assistance of North West Waterwatch Inc. The program was initiated as part of the Priority Project “A Water Quality Monitoring Program and Reporting Framework for the Cradle Coast Region” established with the assistance of the Commonwealth Natural Heritage Trust Fund. The program was continued through Regional Investment Programs One and Two with additional Natural Heritage Trust funding. This program built on an earlier water monitoring program initiated by King Island NRM Group and King Island Waterwatch. Earlier work has been reported on previously (Graham, 2005), (Brown, 2003).

Nine sites were monitored monthly from November 2004 until the end of 2008. One site was selected from each of the major catchments with consideration given to past monitoring by DPIWE, King Island Waterwatch and King Island Council. Details of these sites are included in Appendix A.

In addition Lake Flannigan and a drain associated with it were included due to community concern over declining water levels and interest in possible restoration measures. Lake Flannigan is a wetland of state significance. The lake was monitored from December 2004 to December 2005. The drain was monitored in 2006, 2007 and 2008, when sufficient water was available.

The report presents the results for some of the main physical and chemical indicators of the environmental health of waterways. Electrical conductivity, pH, temperature and dissolved oxygen were measured on site. Turbidity and phosphate were measured within 12 hours using a sample obtained at the site. Samples were frozen if unable to be tested within this time. Some samples were also sent to a NATA accredited laboratory for analysis of total nitrogen and total phosphorus. All sampling, measurement and data management were conducted in accordance with national (ANZECC, 2000b) and state standards (DPIWE, 2003b) and were subject to regular and rigorous quality controls.

No monitoring of flow quantities was carried out, however anecdotal evidence was recorded, for example, no perceptible flow, low flow, water level high.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

6. Assessing Water Quality

ANZECC Guidelines for Water Quality Management

The National Water Quality Management Strategy aims to achieve sustainable use of the nation's water resources by protecting and enhancing their quality while maintaining economic and social development. It brings together the best available scientific knowledge to provide a framework for the sustainable use of water resources in Australia (DEWHA, 1994). The Australian and New Zealand Guidelines for Fresh and Marine Water Quality (referred to as the ANZECC Guidelines) are a component of the National Strategy, and provide a framework for recognising and protecting water quality for the full range of existing environmental values (ANZECC, 2000a). The full ANZECC Guidelines can be found at: www.environment.gov.au/about/councils/anzecc/index.html

The ANZECC Guidelines are designed to help protect the environmental values of water resources, but are not legally-binding standards due to significant gaps in our understanding of aquatic ecosystems and the ways in which they interact with contaminants. Use of the ANZECC Guidelines should, however, provide some level of confidence that risks to our waterways can be detected and effective management actions implemented.

Low-risk Trigger Values (ANZECC Trigger Values)

Low-risk trigger values are concentrations (or loads) of key performance indicators of water quality at which, if not exceeded, there is a low risk that adverse biological effects will occur (ANZECC, 2000a). Some water quality parameters such as pH pose a risk at both low and high values. Exceedences of a trigger value in a waterway indicate the need for further investigation of the possible causes and of management actions to address the risk. The ANZECC Guidelines do not provide trigger values for temperature.

The ANZECC trigger values provide default, low risk water quality trigger values for slightly disturbed Tasmanian ecosystems to be used in the absence of local data (DPIW, 2008).

Table 2. ANZECC 2000 default low-risk trigger values for slightly disturbed ecosystems in Tasmania. Parameter Upland Rivers Lowland Rivers Lakes & Reservoirs Electrical conductivity ≤ 30, ≥ 350 μS/cm ≤ 125, ≥ 2200 μS/cm ≤ 20, ≥ 30 μS/cm pH ≤ 6.5, ≥ 7.5 ≤ 6.5, ≥ 7.5 ≤ 6.5, ≥ 8.0 Turbidity ≤ 2, ≥ 25 FTU ≤ 6, ≥ 50 FTU ≤ 1, ≥ 20 FTU Reactive phosphate ≥ 0.005 mg/L ≥ 0.02 mg/L ≥ 0.005 mg/L Total phosphorus ≥ 0.013 mg/L ≥ 0.05 mg/L ≥ 0.010 mg/L Total nitrogen ≥ 0.48 mg/L ≥ 0.50 mg/L ≥ 0.35 mg/L

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Local Site-Specific Current-Status Trigger Values for King Island

Current-status trigger values are concentrations or loads of water quality indicators that reflect existing ecosystem condition, and therefore provide a target for ecosystem maintenance and a benchmark against which future water quality trends may be monitored (DPIW, 2008).

Water quality data collected on King Island has been analysed and results from 2004, 2005 and 2006 have been used to generate local site-specific current-status trigger values. These trigger values are calculated from the 80th percentiles of the data (20th percentiles for pH as well).

The collection of over two years of monthly water quality data means that these local trigger values are available for comparison. This is in line with the ANZECC guideline that, when sufficient local data is obtained, water quality targets and standards appropriate to the specific water body and site will be developed (ANZECC, 2000a).

The local trigger values can be used as a measure of the water quality characteristics of waterways on King Island during that period. In this report these trigger values have been used as benchmarks to compare data from 2007 and 2008. The 2007 and the 2008 results have been analysed separately where possible and the 80th percentile levels compared to the trigger values to determine if water quality in those waterways is improving or not. As an example, a decrease of the 80th percentile levels for turbidity, electrical conductivity and nutrients such as phosphate could indicate an improvement in water quality.

The local trigger values can act as default water quality targets for other sites where sufficient site specific data does not exist. They can assist in assessing progress towards other Cradle Coast NRM, King Island NRM Group and Tasmania Together targets, and in the process of setting Aspirational Targets and Water Quality Objectives.

The development of local trigger values for turbidity fulfils part of Cradle Coast NRM Management Action Target Water 3, “Use historic data to establish trigger values for …turbidity in selected catchments….” (Cradle Coast NRM, 2005).

The development of the local trigger values for turbidity will allow the tracking of progress on the island towards Cradle Coast NRM Resource Condition Target Water 2, “No increasing trend from 2006 trigger levels in turbidity … at all monitored sites: by 2010. “(Cradle Coast NRM, 2005).

The development of local trigger values for electrical conductivity goes part way towards assessing progress towards Cradle Coast NRM Resource Condition Target Water 4, “Surface water salt loads maintained below established trigger levels in key catchments including King Island: by 2015.” (Cradle Coast NRM, 2005). In the absence of flow data it is not possible to determine surface water salt loads but it is possible to calculate surface water salt levels.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Table 3. Local site-specific current-status trigger values Site Code Waterbody EC pH pH Temp- Turbidity Dissolved Phos- (µS/cm) 20th 80th erature (FTU) Oxygen phate (oC) (mg/L) (ppm) KINGIS01 Sea Elephant River 675 5.93 6.66 17.0 63 7.14 0.60 KINGIS04 Porky Creek 2556 7.25 7.78 16.4 22 6.54 1.11 KINGIS05 Grassy River 439 6.70 6.99 15.5 79 9.70 0.76 KINGIS06 Egg Lagoon Creek 6362 7.37 7.72 18.2 59 9.32 0.35 KINGIS07 Seal River 21140 6.58 7.19 16.0 133 4.11 0.50 KINGIS09 Ettrick River 799 7.86 8.13 15.2 65 10.80 0.32 KINGIS11 Yarra Creek 458 6.58 7.05 15.1 66 9.60 1.29

Notes: The local site specific, current-status, trigger values for electrical conductivity (salinity), temperature, turbidity, dissolved oxygen and phosphate were determined by calculating the 80th percentiles of monthly water quality data collected from September 2004 to December 2006. The 20th percentiles were also calculated for pH as recommended levels usually include maximum and minimum values.

It has not been possible to develop local trigger values for all sites. Water quality data from Yellow Rock River, Fraser River, Lake Flannigan and the drain associated with Lake Flannigan is not contiguous enough to analyse statistically. Local trigger values have been calculated for Egg Lagoon Creek and Seal River; however Egg Lagoon Creek appears to be influenced by groundwater inflow and the Seal River by tidal inflow.

Protected Environmental Values (PEVs)

The State Policy on Water Quality Management 1997 is designed to maintain or enhance the quality of Tasmanian surface waters (Tasmanian Government, 1997). The Board of Environmental Management and Pollution Control called on all interested stakeholders and community members to help set community water values for regional wetlands and waterways. Information from the community was used to develop Protected Environmental Values to be used in management planning.

As part of the process of developing PEVs on King Island, Community Water Values were collected (DPIWE, 2003a.) The values for all waterways on the island included: • Maintain water quality at a level suitable for homestead use; • Maintain water quality and quantity that is suitable for dairy sheds; • Maintain areas free of algal blooms; • Maintain water quality in all creeks such that they are suitable to be walked next to; • Maintain the aesthetic values of the natural waterways; • Maintain all river and stream riparian zones for their biodiversity and for their role as wildlife corridors; • Maintain the water quality in all lagoons to support the Green and Gold Frog and the Striped Marsh Frog.

A full list of PEVs for King Island can be found at: www.environment.tas.gov.au/index.aspx?base=180

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Water Quality Targets and Objectives

The ANZECC Guidelines suggest that, for the long term management of water resources, Water Quality Targets and Water Quality Objectives should be set. Water Quality Targets are levels of water quality parameters or descriptive statements, which are considered to be sufficient to maintain or improve aquatic assets such as ecological health or drinking water. Water Quality Targets require stakeholder input and consensus. They build on Protected Environmental Values and also consider social, cultural, economic and political factors. These targets can be used by managers to measure and report on performance. Water Quality Objectives are derived from the most stringent Water Quality Targets (ANZECC, 2000a).

7. Assessing Stream Condition

The Australian River Assessment System (AUSRIVAS)

The Australian River Assessment System (AUSRIVAS) is a rapid biological protocol which has been developed to allow for cost effective assessments of stream condition based on the collection and identification of aquatic macroinvertebrates. It is a standardised, national system.

In Tasmania, an intensive six-year assessment of relatively un-impacted, reference sites and impacted test sites led to the development of a model which can predict the macroinvertebrate groups expected to occur at a site in the absence of environmental stress, such as pollution, habitat degradation or flow regulation.

Assessment involves using a net to collect macroinvertebrate streamlife samples from a riffle, run or edgewater habitat. Up to 60 minutes is then spent collecting up to 200 individuals. The streamlife is preserved and later identified, usually to family level (e.g. Leptoceridae or stick caddis). The different types of streamlife found and the characteristics of the waterway are entered into the relevant AUSRIVAS predictive model. The model compares the population of macroinvertebrates observed at a specific site to the expected population and generates an O/E ratio. This number is used to assign a rating and band to the site.

Relatively unimpacted sites can be expected to support populations of macroinvertebrates similar to those observed at reference sites and have O/E scores near 1 and a band of A. The more disturbed a site is, the more likely that sensitive types of streamlife will not be observed and the score and band will be lower. Table 4 provides the ranges of AUSRIVAS O/E scores, the ratings and the bands used in this report.

AUSRIVAS has been shown to be sensitive to impacts from acid mine drainage, intensive agriculture and river regulation.

More information about the AUSRIVAS protocol can be found at: www.ausrivas.canberra.edu.au/ausrivas

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Table 4. Modified ANZECC rankings for AUSRIVAS site-specific OE scores. Rating Band OE Score Description More diverse than reference sites indicating More biologically diverse X >1.13 a potentially biodiverse site or mild than reference organic enrichment. Within 80% of reference sites. Reference sites Similar to reference A 1.13-0.88 are chosen to be as pristine and unimpacted by human activity as possible. Fewer families than expected are observed Significantly impaired B 0.87-0.63 indicating potentially mild to moderate impact on water and/or habitat quality. Many fewer families than expected are Severely impaired C 0.62-0.38 observed indicating moderate to severe impact on water and/or habitat quality. A highly degraded site with few families indicating Extremely impaired D <0.38 very poor water and/or habitat quality.

To generate rankings at different sites where AUSRIVAS assessments may have been carried out in different habitats and seasons this report has chosen one predictive model to generate a ranking. This follows the protocol used by DPIPWE (T Krasnicki 2009, pers.comm.).

Where possible, the ranking for a site is determined by the combined season riffle model incorporating the results from two consecutive seasons. The combined riffle model is considered to be the most sensitive, have the greatest predictive capacity and give the best representation of the condition of a site.

Where it is not possible to use the combined season riffle model, then the ranking for a site is determined from the single season riffle model. (The riffle habitat may not have been sampled for two consecutive seasons or the combined season model may consider the site to be outside of its experience).

Where it is not possible to use a riffle model, then the ranking is determined by the combined season edge model. (A riffle habitat may not occur at the site).

Where it is not possible to use the combined season edge model, then the final band allocation is determined by the single season edge model

Where the O/E score for a site is below reference condition (bands B, C or D), the ANZECC Guidelines recommend management actions be undertaken to return the site to reference condition.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

River Condition Benchmark Ratings for King Island

AUSRIVAS rapid biological assessments were carried out at 8 of the water quality sites in 2005 and 2006. These results have been analysed using the AUSRIVAS predictive model to calculate benchmark ratings. The calculation of AUSRIVAS benchmark ratings for the sites on King Island goes part way towards Cradle Coast NRM MATW1: Establish river condition benchmarks in priority (CFEV) catchments/areas: by 2009 (Cradle Coast NRM, 2005).

Table 5. River Condition Benchmarks for King Island. Site Code Waterbody Season and Habitat O/E SCORE Benchmark Rating

KINGIS01 Sea Elephant River Spring 2005 Edge 0.41 C

KINGIS02 Fraser River Spring 2005 Edge 0.69 B

KINGIS04 Porky Creek Spring 2005 Edge 0.43 C Outside experience KINGIS05 Grassy River Not available Not available of model KINGIS06 Egg Lagoon Creek Spring 2005 Edge 0.49 C

KINGIS07 Seal River Spring 2005 Edge 0.62 B Combined Spring 2005, Autumn KINGIS09 Ettrick River 0.63 B 2006 Riffle Combined Autumn and Spring KINGIS11 Yarra Creek 0.73 B 2005 Riffle

Notes: In the development of the predictive model for Tasmania, no reference or test sites were chosen from King Island. This report has still used the model, as it is the best tool available for analysing the information that has been collected.

It was not possible to generate an O/E score or Benchmark Rating for KINGIS05, Grassy River, as it was outside of the experience of the AUSRIVAS predictive model. KINGIS03, Yellow Rock River, KINGIS05, Lake Flannigan and KINGIS10, Lake Flannigan Drain did not have suitable habitats for AUSRIVAS assessment.

Tasmanian River Condition Index

A Tasmanian River Condition Index has been developed for Tasmanian waters. This index is very comprehensive and includes assessment of aquatic life, streamside zone, physical form and hydrology (flow). The methodology used is much more time consuming than the current water quality and AUSRIVAS assessment but would provide a better overall picture of catchment health. It is worth considering the adoption of this for key catchments if resources allow. More information is available at: http://www.dpiw.tas.gov.au/inter.nsf/WebPages/LBUN-4YG9G9?open

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

8. The Sites

Sea Elephant River at Bicentennial Road Site Code: KINGIS01

The Sea Elephant is the largest catchment on King Island. The mid to upper reaches of the Sea Elephant River drain an extensive area of agricultural land cleared for grazing. The lower reaches of the river drain the Lavinia State Reserve, a Ramsar wetland. The monitoring site is at the lower end of impacted agricultural land (NWWW, 2005).

Surrounding land use at this site is agriculture, predominantly grazing by stock. The streambed is composed of fine sand, clay and gravel overlain by silt and also, at times, by green algae. The riparian vegetation is a narrow band of mainly native species, with the intrusion of some pasture grasses. Work has been undertaken to exclude stock and rehabilitate riparian vegetation. Flow levels are very low during summer and autumn.

An AUSRIVAS rapid biological assessment of this site gave it a C rating, as many fewer aquatic macroinvertebrate families than expected were observed. This suggests possible moderate to severe impacts on water and/or habitat quality. Families expected to occur but not observed include stonefly larvae from the family Notonemouridae, mayfly larvae from the family Leptophlebiidae, marsh beetle larvae from the family Scirtidae and midge larvae from the sub-family Tanypodinae. There are significant amounts of large wood in the river, which can provide habitat for fish and macroinvertebrates; however the low flows in some seasons would greatly limit the amount of available habitat.

Figure 2: Sea Elephant River at Bicentennial Road, October 2008.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 3: Electrical conductivity at Sea Elephant River, 2007 to 2008.

Electrical conductivity readings in both 2007 and 2008 have been considerably lower than the ANZECC guideline value. 80th percentiles in both 2007 and 2008 have exceeded the local trigger value calculated from 2005 and 2006 data. This may be due to the low rainfalls and low flows experienced in 2007 and 2008 allowing for a greater influence by saline groundwater.

pH at Sea Elephant River, 2007 to 2008 8.50

8.00

7.50

7.00 pH 6.50 05/06 80th pH (Units)pH 6.00 05/06 20th ANZECC 80th 5.50 ANZECC 20th 5.00 3 3 3 3 3 2 2 3 2 2 1 0 0 1 1 1 8 7 0 9 9 ------D J M M J O D F A J S a u u e c e e p e c n a a l- t b r l- p - - r y 0 c 0 0 0 ------0 - 7 0 0 0 0 8 0 8 7 0 7 8 8 8 7 7 7

Figure 4: pH at Sea Elephant River, 2007 to 2008. pH readings in both 2007 and 2008 indicate that the river can be slightly acidic. The readings have, at times, been lower than the ANZECC 20th percentile guideline value. The local trigger values calculated from 2005 and 2006 data are also lower than the ANZECC guideline values.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Temperature at Sea Elephant River, 2007 to 2008

19.0 17.0 15.0 Temp. 13.0 05/06 11.0 80th 07 80th 9.0

Temperature (Degrees C) (Degrees Temperature 7.0 08 80th 5.0 3 3 3 3 2 2 2 3 3 2 2 1 0 0 1 1 7 9 9 1 0 9 9 ------D J M M J S N J M M J S a u a u e e o e c n a a l- p n a a l- p - - r y 0 v - r y 0 0 0 - - - 0 - - 0 - 7 0 0 0 - 8 0 8 7 0 7 8 0 8 7 7 7 8 8

Figure 5: Temperature at Sea Elephant River, 2007 to 2008.

Temperature readings have shown seasonal variation. The 80th percentiles in both 2007 and 2008 have been slightly lower than the local trigger value calculated from 2005 and 2006 data.

Figure 6: Turbidity at Sea Elephant River, 2007 to 2008.

Turbidity readings in both 2007 and 2008 have regularly exceeded the ANZECC guideline values. The 80th percentiles in 2007 and 2008 have been very similar to the local trigger value calculated from 2005 and 2006 data. Peaks in turbidity readings seem to coincide with high flow levels, for example, the peak in July 2008 was recorded when the stream water level was raised.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Dissolved oxygen at Sea Elephant River, 2007 to 2008 12.00

10.00

8.00 DO

6.00 05/06 80th DO (mg/L) 4.00 07 80th 2.00 08 80th 0.00 3 3 3 2 2 2 3 3 2 2 1 0 0 1 7 9 9 1 0 9 9 ------D J M J S N J M M J S a u a u e e o e c n a l- p n a a l- p - - r 0 v - r y 0 0 0 - - - 0 - - 0 7 0 0 0 - 8 0 8 7 7 8 0 8 7 7 8 8

Figure 7: Dissolved oxygen at Sea Elephant River, 2007 and 2008.

80th percentiles for dissolved oxygen have been higher in both 2007 and 2008 than the local trigger value calculated from 2005 and 2006 data.

Phosphate at Sea Elephant River, 2007 to 2008 1.00 0.90 0.80 0.70 0.60 0.50 0.40 Phosphate

Phosphate (ppm) 0.30 0.20 05/06, 07 & 0.10 08 80th 0.00 3 3 3 3 2 2 2 3 3 2 2 1 0 0 1 1 7 9 9 1 0 9 9 ------D J M M J S N J M M J S a u a u e e o e c n a a l- p n a a l- p - - r y 0 v - r y 0 0 0 - - - 0 - - 0 - 7 0 0 0 - 8 0 8 7 0 7 8 0 8 7 7 7 8 8

Figure 8: Phosphate at Sea Elephant River, 2007 and 2008.

80th percentiles for phosphate have remained similar throughout 2005, 2006, 2007 and 2008 and have consistently been much higher than the ANZECC guideline value. These high levels of phosphate may be contributing to the large amounts of green algae observed at this site at times.

Total phosphorus was sampled for on 11 occasions between 2005 and 2008. Nine samples exceeded the ANZECC guideline, from slightly over to seven times the guideline.

Total nitrogen was sampled for on nine occasions, between 2006 and 2008. Eight samples exceeded the ANZECC guideline, from slightly over to four times the guideline.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Fraser River at Fraser Road Site Code: KINGIS02

The Fraser River drains the Pegarah Plateau to the east. Much of the upper and mid catchment has been cleared and land use is predominantly grazing by livestock. There has been extensive fencing of riparian and remnant vegetation in the catchment through the efforts of the Pegarah Landcare Group. The monitoring site is in the lower catchment. The re-establishment of a sand mine is proposed for the lower catchment (NWWW, 2005). A refuse disposal site has been developed at the top of the catchment.

Surrounding land use at this site is native forest and residential, with an agricultural belt upstream. The streambed is dominated by sand and silt with some clay and gravel and a large amount of detritus. The thick riparian vegetation is predominantly native. There is usually little or no flow at the monitoring site from summer through to early winter.

An AUSRIVAS rapid biological assessment of this site gave it a B rating as fewer aquatic macroinvertebrate families than expected were observed. This suggests possible mild to moderate impacts on water and/or habitat quality. Families expected to occur but not observed include stonefly larvae from the family Notonemouridae and midge larvae from the sub-family Tanypodinae.

Figure 9: Fraser River at Fraser Road, September 2008.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 10: Electrical conductivity at Fraser River, 2005 to 2008.

Electrical conductivity readings from 2005 to 2008 have been considerably lower than the ANZECC guideline value. This reflects the absence of highly saline soils throughout the catchment. The peaks in December 2005 and June 2007 were recorded when flow was very low allowing for a greater influence by saline groundwater.

pH at Fraser River, 2005 to 2008 8.50 8.00 7.50 7.00 6.50

pH (Units)pH 6.00 pH 5.50 ANZECC 80th 5.00 ANZECC 20th 4.50 2 2 2 1 2 3 2 3 2 3 2 4 7 9 - 6 1 7 0 8 0 - - - - A ------D A O D u S J S N J S e e u e u e u c e g l o l c g t c - p - p v - p - - - - 0 - 0 - - 0 - 0 0 0 0 6 0 7 0 0 8 0 8 5 5 5 6 7 7 8

Figure 11: pH at Fraser River, 2005 to 2008. pH readings from 2005 to 2008 have generally been within the ANZECC guideline values. The very low reading in June 07 was recorded at the resumption of flow following an eight month period when the river was dry.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Temperature at Fraser River, 2005 to 2008 20.0 18.0 16.0 14.0

12.0 Temp. 10.0

Temperature (Degrees C) (Degrees Temperature 8.0 6.0 2 2 2 1 2 3 2 3 2 3 2 4 7 9 - 6 1 7 0 8 0 - - - - A ------D A O D u S J S N J S e e u e u e u c e g l o l c g t c - p - p v - p - - - - 0 - 0 - - 0 - 0 0 0 0 6 0 7 0 0 8 0 8 5 5 5 6 7 7 8

Figure 12: Temperature at Fraser River, 2005 to 2008.

Temperature readings from 2005 to 2008 show seasonal variation.

Turbidity at Fraser River, 2005 to 2008 350 300 250 200 150

Turbidity (FTUs) 100 Turbidity 50 ANZECC 0 2 2 2 2 3 3 2 2 2 3 4 7 9 6 0 0 9 9 8 0 ------A O D S A O D A O D u c e e u c e u c e g t c p g t c g t c ------0 0 0 0 0 0 0 0 0 0 5 5 5 6 7 7 7 8 8 8

Figure 13: Turbidity at Fraser River, 2005 to 2008.

Turbidity readings from 2005 to 2008 have regularly exceeded the ANZECC guideline value. Peaks in readings occur at times of very low flow which may be partly due to the presence of tannins and fine litter in the water.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 14: Dissolved oxygen at Fraser River, 2005 to 2008.

Dissolved oxygen readings from 2005 to 2008 show a great deal of variation. The very low readings in December 2005 and November 2007 were recorded when flow was very low.

Phosphate at Fraser River, 2005 to 2008 1.60 1.40 1.20 1.00 Phosphate 0.80 0.60

Phosphate (ppm) 0.40 0.20 0.00 2 2 2 1 3 2 3 2 3 2 4 7 9 - 1 7 0 8 0 - - - - S - - - - - D A O D e J S N J S u u e u c e p e o e c - l p l p g t c 0 - v - - - - - 0 - - 0 - 0 0 0 0 6 7 0 0 8 0 8 5 5 5 7 7 8

Figure 15: Phosphate at Fraser River, 2005 to 2008.

Phosphate readings from 2005 to 2008 have regularly greatly exceeded the ANZECC guideline value. The peaks in readings in December 2005 and 2008 were recorded when flow was very low.

Total phosphorus was sampled for on four occasions, once in 2006 and the other three in 2008. All samples exceeded the ANZECC guideline, from four to 12 times the guideline.

Total nitrogen was sampled for on four occasions, once in 2006 and the other three in 2008. All samples exceeded the ANZECC guideline, from three to five times the guideline.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Yellow Rock River at North Yellow Rock Road Site Code: KINGIS03

This is a highly modified and impacted agricultural catchment in the north of the Island. It has been heavily cleared for livestock grazing. Drainage channels completely disguise the natural stream channel until the lower reaches near the estuary. Drainage and salinity are ongoing issues. The monitoring site is at the lower end of the catchment, upstream of any tidal influence. Past salinity hazard mapping has revealed extremely saline soils upstream of the monitoring site (NWWW, 2005).

Surrounding land use at this site is agriculture, predominantly grazing. The streambed is dominated by fine silt and clay with large amounts of aquatic vegetation. The riparian vegetation is dominated by Melaleuca sp. with some pasture grass and introduced weeds such as thistles. The river contains substantial amounts of large wood. The river at this site is broad and shallow and is dry for some months of the year.

This site was not considered suitable for an AUSRIVAS rapid biological assessment to be carried out. Burrowing crayfish activity has been observed in the riparian zone.

Figure 16: Yellow Rock River at North Yellow Rock Road, September 2008.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 17: Electrical conductivity at Yellow Rock River, 2004 to 2008.

Electrical conductivity readings from 2004 to 2008 have regularly exceeded the ANZECC guideline value. This may be partly due to the extremely saline soils upstream of the monitoring site and the very low flows experienced during drier months allowing for a greater influence by saline groundwater.

pH at Yellow Rock River,

8.50 2004 to 2008

8.00

7.50

7.00

6.50 pH (Units)pH

6.00 pH 5.50 ANZECC 80th 5.00 ANZECC 20th 2 2 2 2 1 2 2 2 2 2 2 9 6 8 8 - 9 7 9 7 7 9 - - - - S ------N A O J e J S N A O D u p u e o u c n n o u c e v g t - p v g t c - - 0 ------0 0 6 0 0 - - 0 0 0 0 6 7 0 0 4 5 5 7 7 8 8 8

Figure 18: pH at Yellow Rock River, 2004 to 2008. pH readings from 2004 to 2008 show variation but are generally within the ANZECC guideline values.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Temperature at Yellow Rock River, 2004 to 2008 19.0

17.0

15.0

13.0

11.0 9.0

Temperature (Degrees C) (Degrees Temperature Temp. 7.0

5.0 2 2 2 2 1 2 3 3 2 2 1 9 6 8 8 - 9 0 1 9 9 - - - - - S - - - - - D N A O J e J A O J S e u p u u e o u c n n u c l c v g t - g t - p - - - 0 - - 0 - 0 - - 0 0 6 0 - 0 0 8 0 0 6 7 0 8 4 5 5 7 7 8

Figure 19: Temperature at Yellow Rock River, 2004 to 2008.

Temperature readings from 2004 to 2008 show seasonal variations.

Turbidity at Yellow Rock River, 2004 to 2008 140

120

100

Turbidity (FTUs) 40 Turbidity 20

0 ANZECC 2 2 2 2 1 2 3 3 2 2 1 9 6 8 8 - 9 0 1 9 9 - - - - - S - - - - - D N A O J e J A O J S e u p u u e o u c n n u c l c v g t - g t - p - - - 0 - - 0 - 0 - - 0 0 6 0 - 0 0 8 0 0 6 7 0 8 4 5 5 7 7 8

Figure 20: Turbidity at Yellow Rock River, 2004 to 2008

Turbidity readings from 2004 to 2008 exceeded the ANZECC guideline value on a number of occasions. The peaks in readings in August and September 2005 were recorded when flow was low and instream water plants were almost completely covering the river.

The peak in June 2006 was recorded at the first resumption of flow following a period when the river was dry. The peak in August 2008 was recorded at a time when the water level was high. These peaks may be partly due to run-off and erosion from the surrounding catchment.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 21: Dissolved oxygen at Yellow Rock River, 2004 to 2008.

Dissolved oxygen readings from 2004 to 2008 show a great deal of variation. The very low reading in November 2005 was recorded during a time of low flow.

Phosphate at Yellow Rock River,

2.50 2004 to 2008

2.00

1.50

1.00

Phosphate (ppm) Phosphate 0.50

0.00 2 2 2 2 1 2 3 3 2 2 1 9 6 8 8 - 9 0 1 9 9 - - - - - S - - - - - D N A O J e J A O J S e u p u u e o u c n n u c l- c v g t - g t p - - - 0 - - 0 - 0 - - 0 0 6 0 - 0 0 8 0 0 6 7 0 8 4 5 5 7 7 8

Figure 22: Phosphate at Yellow Rock River, 2004 to 2008.

Phosphate readings from 2004 to 2008 have regularly greatly exceeded the ANZECC guideline value. Peaks in phosphate mirrored peaks in turbidity and may be associated with run-off during high flow levels.

Total phosphorus was sampled for on three occasions in 2008. All samples exceeded the ANZECC guideline, from three to eight times the guideline. Total nitrogen was sampled for on four occasions, once in 2006 and the other three in 2008. All samples exceeded the ANZECC guideline, from three to five times the guideline. The high levels of nutrients may be contributing to the large amounts of instream water plants observed at this site.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Porky Creek at North Road Site Code: KINGIS04

Porky Creek discharges to the west coast of the island. Within this catchment there is severe degradation from agriculture. Much of the riparian vegetation has been removed and there is a significant amount of erosion in some part of the catchment. Past salt hazard mapping indicates high levels of salt in parts of the Porky Creek catchment. Past effluent from an abattoir approximately four kilometres upstream appears to have caused extensive nutrient enrichment to some parts of Porky Creek (NWWW, 2005). The abattoir is currently upgrading its effluent treatment procedures to comply with environmental legislation. This should achieve a substantial improvement in downstream water quality.

Surrounding land use at this lower catchment site includes grazing and a dairy processor. The streambed is dominated by sand and silt although the surface of the stream is often covered by floating aquatic plants such as Azolla sp. and duckweed, suggesting that the river experiences high phosphorus levels. The riparian vegetation is a mix of introduced species, including Boxthorn and pasture grass, with Melaleuca sp. and other natives. The river at this site has very low flows except in times of flood.

An AUSRIVAS rapid biological assessment of this site gave it a C rating, as many fewer aquatic macroinvertebrate families than expected were observed. This suggests possible mild to moderate impacts on water and/or habitat quality. Families expected to occur but not observed include stonefly larvae from the family Notonemouridae, stonefly larvae from the family Gripopterygidae, mayfly larvae from the family Leptophlebiidae and midge larvae from the sub-family Tanypodinae. Low flows would reduce the amount of available habitat and contribute to the low rating.

Figure 23: Porky Creek at North Road, September 2008.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Electrical conductivity at Porky Creek, 2007 to 2008

5000 4500 4000 3500 3000 EC 2500 05/06 80th 2000 EC (µS/cm) 07 80th 1500 1000 08 80th 500 ANZECC 0 2 2 2 3 3 2 2 3 1 2 2 2 4 7 8 0 1 8 7 0 - 7 7 9 ------J - - - F A J A O D F A u A O D e u e l p n u c e p - u c e b r g t c b r 0 g t c ------8 - - - 0 0 0 0 0 0 0 0 0 0 0 7 7 7 7 7 7 8 8 8 8 8

Figure 24: Electrical conductivity at Porky Creek, 2007 to 2008.

Electrical conductivity readings in both 2007 and 2008 have regularly exceeded the ANZECC guideline value, which is consistent with the high levels of salt in parts of the catchment.

80th percentiles in both 2007 and 2008 have regularly exceeded the local trigger value calculated from 2005 and 2006 data. This may be due to the low rainfalls and low flows experienced in 2007 and 2008 allowing for a greater influence by saline groundwater.

pH at Porky Creek, 2007 to 2008 8.50 8.00 7.50 7.00 pH

6.50 05/06 80th pH (Units)pH 6.00 05/06 20th ANZECC 80th 5.50 ANZECC 20th 5.00 2 2 2 3 2 2 3 1 2 2 2 4 7 8 1 8 7 0 - 7 7 9 ------J - - - F A J O D F A u A O D e u e l p n c e p - u c e b r t c b r 0 g t c ------8 - - - 0 0 0 0 0 0 0 0 0 0 7 7 7 7 7 8 8 8 8 8

Figure 25: pH at Porky Creek, 2007 to 2008. pH readings in both 2007 and 2008 have regularly been within both the ANZECC guideline value and the local trigger value calculated from 2005 and 2006 data. The very low reading in June 07 was recorded just after a long period of dry weather and low flow.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Temperature at Porky Creek, 2007 to 2008

19.0 17.0

15.0 Temp. 13.0 05/06 11.0 80th 07 80th 9.0 Temperature (Degrees C) (Degrees Temperature 7.0 08 80th 5.0 2 2 2 3 3 2 2 3 1 2 2 2 4 7 8 0 1 8 7 0 - 7 7 9 ------J - - - F A J A O D F A u A O D e u e l p n u c e p - u c e b r g t c b r 0 g t c ------8 - - - 0 0 0 0 0 0 0 0 0 0 0 7 7 7 7 7 7 8 8 8 8 8

Figure 26: Temperature at Porky Creek, 2007 to 2008.

Temperature readings have shown seasonal variation. The 80th percentiles in 2007 and 2008 have been slightly lower than the local trigger value calculated from 2005 and 2006 data.

Turbidity at Porky Creek, 2007 to 2008 120

100

80 Turbidity

60 05/06 80th 40 07 80th Turbidity (FTUs)

20 08 80th ANZECC 0 2 2 2 3 3 2 2 3 1 2 2 2 4 7 8 0 1 8 7 0 - 7 7 9 ------J - - - F A J A O D F A u A O D e u e l p n u c e p - u c e b r g t c b r 0 g t c ------8 - - - 0 0 0 0 0 0 0 0 0 0 0 7 7 7 7 7 7 8 8 8 8 8

Figure 27: Turbidity at Porky Creek, 2007 to 2008.

Turbidity readings in both 2007 and 2008 have regularly been within the ANZECC guideline value. The 80th percentiles have been very similar to the local trigger value calculated from 2005 and 2006 data. The peak in July 2007 was recorded during a time of high flow. This may be partly due to run-off and erosion from the surrounding catchment. The peak in July 2008 was recorded at a time when the water level was low.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Dissolved oxygen at Porky Creek, 2007 to 2008 14.00

12.00 DO 10.00

8.00 05/06 80th 6.00 DO (mg/L) 07 80th 4.00 2.00 08 80th 0.00 2 2 3 2 2 2 3 2 2 2 1 4 7 1 7 9 9 1 9 9 9 ------D F A J S N J M M J S u a u e e p e o e c b r l- p n a a l- p - 0 v - r y 0 0 - - - - 0 - - 0 0 7 0 0 0 - 8 0 8 7 7 7 8 0 8 7 8 8

Figure 28: Dissolved oxygen at Porky Creek, 2007 to 2008.

80th percentiles for dissolved oxygen have been higher in both 2007 and 2008 than the local trigger value calculated from 2005 and 2006 data. This may be partly due to the extensive coverage of floating aquatic plants, adding oxygen to the waterway during daylight.

Phosphate at Porky Creek, 2007 to 2008 2.50

2.00 Phosphate

1.50 05/06 80th 1.00 07 80th Phosphate (ppm) 0.50 08 80th 0.00 2 2 2 2 2 2 3 2 2 2 1 4 7 8 7 9 9 1 9 9 9 ------D F A J S N J M M J S u a u e e p e o e c b r n p n a a l- p - - v - r y 0 0 - - 0 - - 0 - - 0 0 0 0 0 - 8 0 8 7 7 7 7 8 0 8 7 8 8

Figure 29: Phosphate at Porky Creek, 2007 to 2008. 80th percentiles for phosphate have remained very similar throughout 2005, 2006, 2007 and 2008 and are consistently greatly higher than the ANZECC guideline value. These high values may be contributing to the prolific growth of instream plants observed at some times. Peaks in phosphate readings mirror peaks in turbidity readings.

Total phosphorus was sampled for on ten occasions from 2005 to 2008. Nine of those samples exceeded the ANZECC guideline, from twice to 14 times the guideline. Total nitrogen was sampled for on nine occasions from 2006 to 2008. All samples exceeded the ANZECC guideline, from slightly over to 22 times the guideline.

These high levels of nutrients may be contributing to the large amounts of aquatic plants seen at this site.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Grassy River at Grahams Road Site Code: KINGIS05

The Grassy River catchment has been cleared for grazing but it still contains significant remnant riparian vegetation. The upper catchment reaches are exposed to degradation through unrestricted cattle access, whilst the vegetation of the lower reaches is well preserved due to impenetrable steep gullies and fencing. A dam at the lower end of the Grassy River provides the water supply for the township of Grassy. In previous years this dam has been subjected to Cyanobacteria blue-green algal blooms in summer and autumn. Monitoring at this upper catchment site supplements the Council monitoring at the town water supply source lower in the catchment. The monitoring site experiences severe intermittent erosion, pugging, collapse of banks and vegetation destruction due to cattle access (NWWW, 2005).

Surrounding land use at this site includes grazing and some dairy farming. The streambed is dominated by bedrock and boulder, with some gravel, sand and silt. The riparian vegetation is dominated by pasture grass although it does include a number of native species such as tree ferns and Melaleuca sp.. The river flows all year, although the flow rates are very low in summer and autumn.

AUSRIVAS rapid biological assessment has been carried out at this site, however it was not possible to generate a score or ranking as the river was outside of the experience of the model. One of the river characteristics entered into the model was considered by the model to be too dissimilar to its reference sites to generate a score and ranking. This may have been the depth of the river when an edge sample was taken.

Figure 30: Grassy River at Grahams Road, September 2008.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 31: Electrical conductivity at Grassy River, 2007 to 2008

Electrical conductivity readings in 2007 and 2008 have regularly been considerably lower than the ANZECC guideline value. These low readings reflect the absence of highly saline soils in the catchment. 80th percentiles in 2007 and 2008 have been very similar to the local trigger value calculated from 2005 and 2006 data.

Figure 32: pH at Grassy River, 2007 to 2008. pH readings in both 2007 and 2008 have regularly been within ANZECC guideline values. The local trigger values calculated from 2005 and 2006 data are also within the ANZECC guideline values. The low reading in May 07 was recorded following rain after a long period of dry weather and low flow.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 33: Temperature at Grassy River, 2007 to 2008

Temperature readings have shown seasonal variation. The 80th percentile in 2007 is slightly higher, and that in 2008 is slightly lower, than the local trigger value calculated from 2005 and 2006 data.

Figure 34: Turbidity at Grassy River, 2007 to 2008.

Readings for turbidity in both 2007 and 2008 have regularly exceeded the ANZECC guideline value. 80th percentiles for 2007 and 2008 are very similar to the local trigger value calculated from 2005 and 2006 data. The single peak in turbidity in September 2007 occurred at a time of very high flow and may be due to run-off and erosion from the surrounding catchment.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 35: Dissolved oxygen at Grassy River, 2007 to 2008.

80th percentiles for dissolved oxygen have been higher in both 2007 and 2008 than the local trigger value calculated from 2005 and 2006 data.

Figure 36: Phosphate at Grassy River, 2007 to 2008.

The 80th percentile for phosphate in 2007 is higher than, and the 80th percentile in 2008 lower than, the local trigger value calculated from 2005 and 2006 data. All readings greatly exceed the ANZECC guideline value. The high levels of phosphate in the river may well be contributing to the Cyanobacteria blue-green algal blooms observed downstream of the site in summer and autumn. Peaks in phosphate readings mirror peaks in turbidity readings.

Total phosphorus was sampled for on 11 occasions from 2005 to 2008. All samples exceeded the ANZECC guideline, from slightly over to nine times the guideline. Total nitrogen was sampled for on nine occasions from 2006 to 2008. All samples exceeded the ANZECC guideline, from slightly over to six times the guideline.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Egg Lagoon Creek at Mansons Road Site Code: KINGIS06

The upper Egg Lagoon Creek catchment is an extensively modified drainage system, managed by a Drainage Trust. In the lower part of the catchment Egg Lagoon Creek is a waterway flowing into Nook Swamp, part of the Lavinia State Reserve. Past salt hazard mapping indicates that large areas of the catchment have extremely saline soils. The monitoring site is near the end of an agricultural grazing area where drainage and salinity are ongoing issues (NWWW, 2005). Members of the Drainage Trust have recently built a weir across Egg Lagoon Creek to facilitate extraction of stock water and prevent over-drainage of adjacent peat.

Surrounding land use at this site is predominantly grazing, partly under irrigation. The streambed is dominated by silt and clay, overlaid by algae and duckweed in some seasons. The riparian vegetation is dominated by pasture grasses with a thin strip of Melaleuca sp.. The river at this site has recently been fenced off to exclude stock.

An AUSRIVAS rapid biological assessment of this site gave it a C rating, as many fewer aquatic macroinvertebrate families than expected were observed. This suggests possible mild to moderate impacts on water and/or habitat quality. Families expected to occur but not observed include mayfly larvae from the family Leptophlebiidae, stonefly larvae from the family Gripopterygidae and marsh beetle larvae from the family Scirtidae.

Figure 37: Egg Lagoon Creek at Mansons Road, July 2008.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 38: Electrical conductivity at Egg Lagoon Creek, 2007 to 2008.

Electrical conductivity readings in 2007 and 2008 consistently exceeded the ANZECC guideline value. This reflects inflows of saline groundwater at this site and the presence of extremely saline soils in large parts of the catchment. 80th percentiles for both 2007 and 2008 have been very similar to the local trigger value calculated from 2005 and 2006 data.

Figure 39: pH at Egg Lagoon Creek, 2007 to 200.8 pH readings in 2007 and 2008 have regularly been within ANZECC guideline values. The local trigger values calculated from 2005 and 2006 data are also within the ANZECC guideline values.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 40: Temperature at Egg Lagoon Creek, 2007 to 2008.

Temperature readings have shown seasonal variation. The 80th percentiles in 2007 and 2008 have been very similar to the local trigger value calculated from 2005 and 2006 data.

Figure 41: Turbidity at Egg Lagoon Creek, 2007 to 2008.

80th percentiles for turbidity in 2007 and 2008 have generally been below the ANZECC guideline value and have been slightly lower than the local trigger value calculated from 2005 and 2006 data. The peak in July 2007 was recorded at a time of high flow. This may be partly due to run-off and erosion from the surrounding catchment.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 42: Dissolved oxygen at Egg Lagoon Creek, 2007 to 2008.

80th percentiles for dissolved oxygen have been higher in 2007 and 2008 than the local trigger value calculated from 2005 and 2006 data. Large variations in dissolved oxygen readings may be partly due to the prolific growth of algae and duckweed observed in some months and the decomposition of the algae and duckweed during times of low flow.

Figure 43: Phosphate at Egg Lagoon Creek, 2007 and 2008

80th percentiles for phosphate in both 2007 and 2008 are higher than the local trigger value calculated from 2005 and 2006 data and also greatly exceed the ANZECC guideline value. Peaks in December 2007 and July 2008 were recorded following rain events. Total phosphorus was sampled for on 11 occasions from 2005 to 2008. All samples exceeded the ANZECC guideline, from twice to eight times the guideline. Total nitrogen was sampled for on nine occasions from 2006 to 2008. All samples exceeded the ANZECC guideline, from three to 26 times the guideline. The high levels of nutrients may well be contributing to the algae and duckweed observed at this site.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Seal River at Seal River Road Site Code: KINGIS07

The site is part of a unique coastal wetland complex (Big Lake and Colliers Swamp) which is downstream of a major agricultural area. Past salt hazard mapping indicates extremely saline soils in the mid to lower Seal River Catchment (NWWW, 2005).

Surrounding land use at this site includes native forest, cropping and grazing. The streambed at this site is dominated by sand, gravel and silt. The thick riparian vegetation is mainly native Melaleuca sp. forest with some introduced species such as pasture grasses. Ammobium calyceroides, (Spiny Everlasting), an uncommon Tasmanian endemic species, occurs on the riverbank. The river at this site is tidally influenced in summer and autumn due to lower freshwater flows.

An AUSRIVAS rapid biological assessment of this site gave it a B rating, as fewer aquatic macroinvertebrate families than expected were observed. This suggests possible mild to moderate impacts on water and/or habitat quality. Families expected to occur but not observed include stonefly larvae from the family Gripopterygidae, mayfly larvae from the family Leptophlebiidae and midge larvae from the sub-family Tanypodinae. Burrowing crayfish activity is often observed in the riparian zone.

Figure 44: Seal River at Seal River Road, September 2008.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 45: Electrical conductivity at Seal River, 2007 to 2008.

Electrical conductivity readings in 2007 and 2008 have regularly exceeded the ANZECC guideline value during summer and autumn, influenced by low freshwater flows and greater tidal influence. The high readings also reflect the presence of extremely saline soils in the middle and lower catchment. The 80th percentile in 2007 has been higher; while that in 2008 has been lower, than the local trigger value calculated from 2005 and 2006 data.

Figure 46: pH at Seal River, 2007 to 2008. pH readings in 2007 and 2008 have regularly been within ANZECC guideline values. The local trigger values calculated from 2005 and 2006 data are also within the ANZECC guideline values. The low reading in June 07 was recorded following rain after a long period of dry weather and the low reading in October 2007 was also recorded following a rain event.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 47: Temperature at Seal River, 2007 to 2008.

Temperature readings have shown seasonal variation. The 80th percentile in 2007 is slightly higher and that in 2008 is slightly lower, than the local trigger value calculated from 2005 and 2006 data.

Figure 48: Turbidity at Seal River, 2007 to 2008.

Turbidity readings in 2007 and 2008 have regularly exceeded the ANZECC guideline value. The 2007 and 2008 80th percentiles are slightly lower than the local trigger value calculated from 2005 and 2006 data. Peaks in readings coincide with times of both very high flow, which may be partly due to run-off and erosion, and very low flow which may be partly due to the presence of tannins and fine leaf material in the water.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 49: Dissolved oxygen at Seal River, 2007 to 2008.

80th percentiles for dissolved oxygen have been considerably higher in 2007 and 2008 than the local trigger value calculated from 2005 and 2006 data.

Figure 50: Phosphate at Seal River, 2007 to 2008.

Phosphate readings are regularly much higher than the ANZECC guideline value. 80th percentiles for phosphate in 2007 and 2008 are lower than the local trigger value calculated from 2005 and 2006 data. The peak in May 2008 was recorded during a time of high flow suggesting run-off from the surrounding catchment.

Total phosphorus was sampled for on 10 occasions from 2005 to 2008. All samples exceeded the ANZECC guideline, from twice to nine times the guideline.

Total nitrogen was sampled for on nine occasions from 2006 to 2008. All samples exceeded the ANZECC guideline, from slightly over to seven times the guideline.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Ettrick River at old DPIW Monitoring Station Site Code: KINGIS09

The mid to upper reaches of the Ettrick drain extensively cleared grazing land. The lower reaches flow through relatively well-vegetated areas. The Ettrick is the only river on the island with a well-defined riffle, run and pool system. Visually this is the cleanest river on the island. This lower catchment site was once used as a DPIW monitoring station and weir set up to measure streamflow (NWWW, 2005). The weir provides a barrier to any possible tidal influence.

Surrounding land use is predominantly grazing by stock. The streambed is a mixture of boulder, bedrock, cobble, gravel and pebble overlaid by algae and detritus. Despite unrestricted stock access, the thick riparian zone is in fairly good condition and is dominated by natives with some intrusion by pasture grass. The river flows all year round.

An AUSRIVAS rapid biological assessment of this site gave it a B rating as fewer aquatic macroinvertebrate families than expected were observed. This suggests possible mild to moderate impacts on water and/or habitat quality. Families expected to occur but not observed include adult riffle beetles from the family Elmidae and marsh beetle larvae from the family Scirtidae. Large wood in the river does provide some habitat for fish and macroinvertebrates. Burrowing crayfish activity has been observed in the riparian zone.

Figure 51: Ettrick River at old DPIW Monitoring Station, November 2008.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 52: Electrical conductivity at Ettrick River, 2007 to 2008.

Electrical conductivity readings in 2007 and 2008 have been considerably lower than the ANZECC guideline value. These readings reflect the absence of highly saline soils throughout the catchment as well as the effect of the weir providing a barrier to tidal influences.

80th percentiles in 2007 and 2008 have exceeded the local trigger value calculated from 2005 and 2006 data. This may be due to the low rainfalls and low flows experienced in 2007 and 2008 allowing for a greater influence by saline groundwater.

Figure 53: pH at Ettrick River, 2007 to 2008. pH readings in 2007 and 2008 have regularly been within ANZECC guideline values. The local trigger values calculated from 2005 and 2006 data are higher than the ANZECC guideline values.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 54: Temperature at Ettrick River, 2007 to 2008.

Temperature readings have shown seasonal variation. The 80th percentiles in 2007 and 2008 have been similar to the local trigger value calculated from 2005 and 2006 data.

Figure 55: Turbidity at Ettrick River, 2007 to 2008.

Turbidity readings in 2007 and 2008 have regularly exceeded the ANZECC guideline value. The 2007 and 2008 80th percentiles are slightly higher than the local trigger value calculated from 2005 and 2006 data. The peaks in turbidity readings are associated with times of high flow and may be partly caused by run-off and erosion from the surrounding catchment.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 56: Dissolved oxygen at Ettrick River, 2007 to 2008.

80th percentiles for dissolved oxygen have been higher in 2007 and 2008 than the local trigger value calculated from 2005 and 2006 data. In general the readings are relatively high in relation to other rivers on King Island and are indicative of a healthy river.

Figure 57: Phosphate at Ettrick River, 2007 to 2008.

80th percentiles for phosphate in 2007 and 2008 are higher than the local trigger value calculated from 2005 and 2006 data. The 80th percentiles for phosphate in 2005/2006, 2007 and 2008 are all much higher than the ANZECC guideline value. Peaks in phosphate readings mirror peaks in turbidity and may be partly due to run- off and erosion associated with high flow levels.

Total phosphorus was sampled for on 12 occasions from 2005 to 2008. Five samples exceeded the ANZECC guideline, from slightly over to nine times the guideline. Total nitrogen was sampled for on ten occasions from 2006 to 2008. Seven samples exceeded the ANZECC guideline, from slightly over to six times the guideline. In general nutrient levels at this site are relatively low compared to other sites on the island.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Yarra Creek at Millwood Road Site Code: KINGIS11

In its upper and mid reaches, Yarra Creek is a diffuse low gradient stream flowing across a very flat plateau. About 2.3 kilometres upstream of the monitoring site the creek undergoes a rapid transition to a deeply incised, high gradient stream, confined by steep and well-vegetated valley sides. Most of the tributaries in this part of the catchment retain moderate to excellent areas of riparian vegetation (NWWW, 2005). Yarra Creek is highly responsive to rainfall. The monitoring site is in the middle of the catchment.

Surrounding land use at this site is predominantly grazing by stock. The stream bed is mixture of bedrock, gravel and pebble with some boulders as well as some finer sediments. The bed is overlaid by algae, detritus and silt. The thick riparian vegetation is predominantly native. The creek is about four metres wide at the sample site.

An AUSRIVAS rapid biological assessment of this site gave it a B rating as fewer aquatic macroinvertebrate families than expected were observed. This suggests possible mild to moderate impacts on water and/or habitat quality. Families expected to occur but not observed include riffle beetle larvae from the family Elmidae and marsh beetle larvae from the family Scirtidae. Large wood in the river provides some habitat for fish and macroinvertebrates; however silt makes the stream bed less habitable.

Figure 58: Yarra Creek at Millwood Road, September 2008.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 59: Electrical conductivity at Yarra Creek, 2007 to 2008

Electrical conductivity readings in 2007 and 2008 have been considerably lower than the ANZECC guideline value. These low readings reflect the absence of highly saline soils in the catchment. The 80th percentile for 2007 is slightly higher than the local trigger value calculated from 2005 and 2006 data, while that from 2008 is very similar to it.

Figure 60: pH at Yarra Creek, 2007 to 2008

pH readings in 2007 and 2008 have regularly been within ANZECC guideline values. The local trigger values calculated from 2005 and 2006 data are also within the ANZECC guideline values. The low reading in May 2007 was recorded following rain after a long period of dry weather and low flow.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 61: Temperature at Yarra Creek, 2007 to 2008

Temperature readings have shown seasonal variation. The 80th percentile in 2007 was the same as, and that from 2008 slightly lower than, the local trigger value calculated from 2005 and 2006 data.

Figure 62: Turbidity at Yarra Creek, 2007 to 2008

80th percentiles for turbidity in 2007 and 2008 have exceeded the ANZECC guideline value. They have also been very similar to the local trigger value calculated from 2005 and 2006 data. Peaks in March 2007 and September 2008 were recorded during times of low flow and may be partly due to the presence of tannin and fine leaf material in the water. Peaks in September 2007 and July 2008 were recorded during times of high flow and may be partly due to run-off and erosion.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 63: Dissolved oxygen at Yarra Creek, 2007 to 2008

80th percentiles for dissolved oxygen have been higher in 2007 and 2008 than the local trigger value calculated from 2005 and 2006 data.

Figure 64: Phosphate at Yarra Creek, 2007 to 2008

80th percentiles for phosphate in 2007 and 2008 are lower than the local trigger value calculated from 2005 and 2006 data. All 80th percentiles greatly exceed the ANZECC guideline value.

Total phosphorus was sampled for on eight occasions from 2006 to 2008. All samples exceeded the ANZECC guideline, from four to 12 times the guideline.

Total nitrogen was sampled for on eight occasions from 2006 to 2008. All but two samples exceeded the ANZECC guideline, from slightly over to seven times the guideline.

The high levels of nutrients may well contribute to the algal growth observed at this site. 54

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Lake Flannigan Site Code: KINGIS08

Lake Flannigan is a wetland of state significance, which has been modified and is undergoing rehabilitation (NWWW, 2005). At times it has a large population of birds, including swans. Surrounding land use at this site is predominantly grazing by stock.

Water quality monitoring occurred monthly from December 2004 to December 2005. The lake was visited throughout 2006, 2007 and 2008 and a photographic record was kept. The water level in the lake varied considerably, completely drying up in autumn 2008.

Figure 65: Lake Flannigan, August 2008

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 66: Electrical conductivity at Lake Flannigan, 2004 to 2005.

Electrical conductivity ranged from 3,300 µS/cm to 6,430 µS/cm. All readings greatly exceeded the ANZECC guidelines for lakes of 30 µS/cm, indicating that the lake tends to be slightly saline (sea water is around 55,000 µS/cm). The variations seem to be linked to water level, lower conductivity readings occurring during times of higher water level and vice versa.

Figure 67: pH at Lake Flannigan, 2004 to 2005.

pH ranged from 7.89 to 9.71. Ten of the 12 samples exceeded the ANZECC guideline for lakes of eight pH units, indicating that the lake tends to be alkaline.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 68: Temperature at Lake Flannigan, 2004 to 2005.

Temperature ranged from 12.4 0C to 23.2 0C, showing seasonal variation.

Figure 69: Turbidity at Lake Flannigan, 2004 to 2005.

Turbidity ranged from 23 FTU to 101 FTU. All samples exceeded the ANZECC guideline for lakes of 20 FTU. These high readings may have been influenced by the muddy edges of the lake and the low water levels on some occasions.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 70: Phosphate at Lake Flannigan, 2004 to 2005.

Phosphate ranged from 0 (below the detection level of the equipment used) to 0.05 mg/L. Three of the samples exceeded the ANZECC guideline for lakes of 0.02 mg/L.

Other water quality parameters were not measured at Lake Flannigan.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Lake Flannigan Drain at Wickham Road Site Code: KINGIS10

This is not a natural waterway; it was constructed to drain surrounding farmland. It flows into Lake Flannigan.

Surrounding land use at this site is predominantly grazing by stock. The vegetation associated with this drain is predominantly pasture grass. The drain has been fenced off to exclude stock.

This site was not considered suitable for an AUSRIVAS rapid biological assessment to be undertaken as it does not have a riffle or edge habitat.

Figure 71: Lake Flannigan Drain at Wickham Road, July 2008

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Figure 72: Electrical Conductivity at Lake Flannigan Drain, 2004 to 2008

Electrical conductivity readings from 2004 to 2008 have regularly greatly exceeded the ANZECC guideline value.

Figure 73: pH at Lake Flannigan Drain, 2004 to 2008. pH readings from 2004 to 2008 have generally been within ANZECC guideline values.

Other water quality parameters were not measured at the Lake Flannigan Drain.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

9. Recommendations

Recommendations for Monitoring

3. The adoption of the Tasmanian River Condition Index for key catchments could be considered if resources allow. This would provide a more integrated measure of river health.

4. The development of Water Quality Targets in key catchments is recommended for long-term management of water resources on King Island.

Recommendations for On-ground Works

Fencing off and allowing riparian vegetation to grow will provide shade for rivers, allowing for higher oxygen levels (more oxygen dissolves in cool water than in warm water). Riparian vegetation along waterways will also act as a filter reducing the amounts of animal manure, fertilisers and other chemicals entering the waterways. Riparian vegetation will act as shelter belts for stock and pasture.

The continued adoption of next practice land management techniques by landholders across the island will improve water quality through limiting the entry of sediment and nutrients into waterways.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Appendix 1: Site Locations

Site Code Site Name Easting Northing KINGIS01 Sea Elephant River at Bicentennial Road 248461 5588613 KINGIS02 Fraser River at Fraser Road 251889 5578704 KINGIS03 Yellow Rock River at North Yellow Rock Road 233560 5599910 KINGIS04 Porky Creek at North Road 232340 5583130 KINGIS05 Grassy River at Grahams Road 248591 5565875 KINGIS06 Egg Lagoon Creek at Mansons Road 245991 5604957 KINGIS07 Seal River at Seal River Road 240920 5557000 KINGIS08 Lake Flannigan 239160 5610280 KINGIS09 Ettrick River at old DPIW Monitoring Station 235180 5568660 KINGIS10 Lake Flannigan drain 239660 5610510 KINGIS11 Yarra Creek at Millwood Road 251569 5567893

Appendix 2: Site Characteristics for the AUSRIVAS model

Site Code Catchment size Distance Bedslope Elevation Streamclass above site from source (m) (km2) (km) KINGIS01 230 29 0 19 4 KINGIS03 128 0 KINGIS04 58 9 0 17 3 KINGIS05 50 5 .0025 72 3 KINGIS06 20 7 0 23 3 KINGIS07 46 14 0 27 3 KINGIS09 41 12 .006 42 3 KINGIS11 47 12 .004 74 4

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Appendix 3: Water Quality Parameters

Electrical Conductivity (EC) is a measure of the dissolved salts in water as measured by its ability to conduct electricity. It is used to indicate the salinity level in a waterbody. It is a useful general measure of water quality. The background electrical conductivity of a waterway is influenced by the geology of the catchment and by the interaction between surface flows and groundwater recharge into a river. Human activities such as land- clearing, drains, irrigation, sewage and other forms of discharge can alter the conductivity range in a waterway. Aquatic life needs natural salts for growth; however life in a waterway is adapted to a specific range and large variations can adversely affect sensitive fish and macroinvertebrates. pH is a measure of the acidity of a waterway with the acidity of water increasing as the pH gets lower. The pH of a waterway is affected by the geology of the catchment with variations occurring throughout a day due to variations in plant photosynthesis. All aquatic life is adapted to a certain pH range and levels higher or lower than this range can cause sensitive fish and macroinvertebrates to disappear. Human influences on the pH of waterways include the disturbance of acid-sulphate soils and associated run-off. .

Temperature is an important factor because it affects the rate of many biological and chemical processes in a waterway. It also affects the oxygen concentration as cooler water can dissolve more oxygen gas than warmer water. Water temperature can be affected by air temperature, the time of day, the season, the amount of riparian shading, water flow and water turbidity. High water temperatures can cause sensitive fish and macroinvertebrates to disappear.

Turbidity is a measure of water clarity caused by the presence of suspended solids in a waterbody as well as colour from chemicals such as tannins. High turbidity can raise the water temperature as the suspended particles absorb warmth, reduce the rate of photosynthesis and therefore make less oxygen available for aquatic life. It can also encourage the growth of blue-green algae, clog the gills of fish and other aquatic animals and reduce available habitat as particles settle on and between a rocky streambed. Suspended particles can enter a waterway through natural or human caused processes such as soil erosion, water discharge, urban runoff, excessive algal growth or disturbance to the river channel or banks. High turbidity levels can cause sensitive fish and macroinvertebrates to disappear.

Dissolved oxygen is necessary for all aquatic animals. Aquatic fish and macroinvertebrates breathe the oxygen dissolved in water. Dissolved oxygen levels vary with water temperature, altitude, depth, flow and daily and seasonal cycles. Organic waste in a waterway such as sewerage, animal manure and run-off from dairies and abattoirs will reduce the oxygen levels as the waste is decomposed by bacteria. Waterways with consistently high dissolved oxygen levels are capable of supporting many different kinds of aquatic animals but low levels can reduce the diversity of fish and macroinvertebrate communities.

Phosphorus is an essential nutrient for plants and animals. Sources of phosphorus in a waterway include the soil and rocks in the catchment as well as wastewater, fertiliser runoff, animal manure and detergents. High levels in a waterway can cause excessive plant or algal growth, including blue-green algae. This excessive growth can result in low flows and elevated water temperatures. As this excessive growth decays it leads to low oxygen levels. High phosphorus levels can adversely affect sensitive fish and macroinvertebrates.

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

Phosphate describes a form of phosphorus combined with oxygen.

Nitrogen is an essential nutrient for plants and animals. Sources of nitrogen in a waterway include the soil and rocks in the catchment as well as wastewater, fertiliser runoff and animal manure. High levels in aquatic or marine environments can lead to excessive plant or algal growth. High nitrogen levels can also adversely affect sensitive fish and macroinvertebrates (Cassidy, 2003).

WATER QUALITY AND STREAM CONDITION ON KING ISLAND, 2004 - 2008

References

ANZECC (2000a). Australian and New Zealand Guidelines for Fresh and Marine Water Quality. National Water Quality Management Strategy Paper No. 4, Volume 1, The Guidelines. Australian and New Zealand Environment and Conservation Council; and Agriculture and Resource Management Council of Australia and New Zealand.

ANZECC (2000b). Australian Guidelines for Water Quality Monitoring and Reporting. National Water Quality Management Strategy Paper No. 7. Australian and New Zealand Environment and Conservation Council; and Agriculture and Resource Management Council of Australia and New Zealand.

Brown, K (2003). King Island Water Quality Data Report 2001-2003. King Island Natural Resource Management Group.

Cassidy, M (2003). Waterwatch Tasmania Reference Manual. Waterwatch Australia, Canberra.

Cradle Coast NRM (2005). Cradle Coast Natural Resource Management Strategy. Cradle Coast Natural Resource Management.

DEWHA (1994). National Water Quality Management Strategy. Department of the Environment, Water, Heritage and the Arts, Canberra.

DPIW (2008). Site - specific trigger values for physico-chemical indicators monitored under the DPIW Baseline Water Monitoring Program. Department of Primary Industries and Water, Hobart.

DPIWE (2003a). Environmental Management Goals for Tasmanian Surface Waters King Island. Department of Primary Industries, Water and Environment, Hobart.

DPIWE (2003b). The Tasmanian Surface Water Quality Monitoring Strategy. Department of Primary Industries, Water and Environment, Hobart.

Graham, B (2005). King Island Water Quality Data Report November 2004 – October 2005. King Island Natural Resource Management Group.

North West Waterwatch (2006), State of Surface Water Report for the Cradle Coast Region of Tasmania 2005. Cradle Coast Natural Resource Management.

Tasmanian Government (1997). The State Policy on Water Quality Management. Tasmanian Government, Hobart