Water Electrical Conductivity (EC)

AUS-TGP-IND-WEC General Moderate confidence

Benchmark Value

1500 μS/cm

Direction: Lower is desirable ↓

Form: MaximumOnly

Scoring Curve

This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context.

Evidence & Context

Beyond 1000 mg/L (approximately 1500 0003μS/cm), broad-scale, direct adverse biological effects become likely across a wide range of biota.

Metric Definition:

The electrical conductivity (EC) of surface waters is a fundamental measure of their ionic content, primarily reflecting the concentration of dissolved inorganic salts.

Benchmark Definition:

EC threshold for broad-scale, direct adverse biological effects.

Justification:

At these levels, most freshwater macrophytes are lost, and significant negative impacts on invertebrate communities are widespread.

Sources (1)

(PDF) Effects of increasing salinity on freshwater ecosystems in Australia - ResearchGate, accessed August 11, 2025, GreyLiterature

(PDF) Effects of increasing salinity on freshwater ecosystems in Australia - ResearchGate

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Supporting Sources (23)

Additional references from the underlying research that informed this benchmark.

(PDF) A review of the salt sensitivity of the Australian freshwater biota, accessed August 11, 2025,

Direct Evidence Journal

Salinity Tolerances of Freshwater Macroinvertebrates

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(PDF) Hunter River Salinity Trading Scheme (HRSTS) - ResearchGate, accessed August 11, 2025,

Contextual Support Direct Evidence Government

(PDF) Hunter River Salinity Trading Scheme (HRSTS) - ResearchGate

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1.5.2.1 Surface water - Bioregional Assessments |, accessed August 11, 2025,

Contextual Support Government

Percentage compliance with ANZECC water quality trigger values for aquatic ecosystems, primary contact recreation and secondary

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5.9 Conductivity | Monitoring & Assessment | US EPA, accessed August 11, 2025,

Contextual Support Government

archive.epa.gov

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A GUIDE TO THE APPLICATION OF THE ANZECC ... - ResearchGate, accessed August 11, 2025,

Contextual Support GreyLiterature

Namoi River Water Quality Objectives explained - NSW Government

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Australian guidelines for water quality monitoring and reporting, accessed August 11, 2025,

Contextual Support Journal

Salinity in the Hunter Regulated River - Bioregional Assessments |

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Preview of Comparison of grazed and cleared temperate grassy woodlands in eastern Australia: patterns in space and inferences in time - ResearchGate, accessed July 10, 2025,

Comparison of grazed and cleared temperate grassy woodlands in eastern Australia: patterns in space and inferences in time - ResearchGate, accessed July 10, 2025,

Contextual Support Journal

Comparison of grazed and cleared temperate grassy woodlands in eastern Australia: patterns in space and inferences in time - ResearchGate

View Source

Preview of Development of regional water quality and catchment guidelines for the conservation of aquatic ecosystems - NSW Environment Protection Authority, accessed July 30, 2025,

Development of regional water quality and catchment guidelines for the conservation of aquatic ecosystems - NSW Environment Protection Authority, accessed July 30, 2025,

Direct Evidence Journal

Queensland Water Quality Guidelines 2009

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Namoi River Water Quality Objectives explained - NSW Government, accessed August 11, 2025,

Direct Evidence Government

Percentage compliance with ANZECC water quality trigger values for aquatic ecosystems, primary contact recreation and secondary

View Source

National Guidelines for Water Quality - Department of Natural Resources and Environment Tasmania, accessed August 1, 2025,

Contextual Support

Using the ANZECC Guidelines and Water Quality Objectives in NSW

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Preview of Nationally Threatened Ecological Communities of the Victorian Volcanic Plain: Natural Temperate Grassland & Grassy Eucalypt Woodland - DCCEEW, accessed August 12, 2025,

Nationally Threatened Ecological Communities of the Victorian Volcanic Plain: Natural Temperate Grassland & Grassy Eucalypt Woodland - DCCEEW, accessed August 12, 2025,

Contextual Support Journal

NSW National Parks and Wildlife Service. (2006). Woodland Remnants and Dryland Salinity: Impacts of dryland salinity on woodland remnants in the Southern Tablelands and South-West Slopes of New South Wales.

View Source

Protection of the Environment Operations (Hunter River Salinity Trading Scheme) Regulation 2002, accessed August 11, 2025,

Direct Evidence Journal

Water Pollution Control Policy: Addressing Non-Point Source Pollution - Inquiries Journal

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Salinity - Murray–Darling Basin Authority, accessed August 11, 2025,

Contextual Support Direct Evidence Government

Salinity | Murray–Darling Basin Authority

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Salinity in the Hunter Regulated River - Bioregional Assessments |, accessed August 11, 2025,

Contextual Support Methodology Source Government

Protection of the Environment Operations (Hunter River Salinity Trading Scheme) Regulation 2002

View Source

Preview of Salinity sensitivity in early life stages of an Australian freshwater fish, Murray Cod (Maccullochella peelii peelii Mitchell 1838) - University of Canberra Research Portal, accessed August 11, 2025,

Salinity sensitivity in early life stages of an Australian freshwater fish, Murray Cod (Maccullochella peelii peelii Mitchell 1838) - University of Canberra Research Portal, accessed August 11, 2025,

Direct Evidence GreyLiterature

Salinity sensitivity in early life stages of an Australian freshwater fish, Murray Cod (Maccullochella peelii peelii Mitchell 1838)

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