Water Electrical Conductivity (EC)

AUS-TMS-IND-WEC General Moderate confidence

Benchmark Value

42 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

This scientifically derived limit corresponds directly to an Electrical Conductivity Investigation Trigger Value of 42 µS/cm.

Metric Definition:

Electrical Conductivity (EC) as an investigation trigger value representing chronic exposure limit for magnesium to protect aquatic species.

Benchmark Definition:

This benchmark represents a conservative upper limit for water electrical conductivity to protect aquatic species in a high ecological value system within tropical monsoonal savannas under industrial use.

Justification:

Derived from site-specific ecotoxicological studies on local aquatic species and aligned with the highest level of ecological protection.

Sources (1)

Preview of Water Quality Guidelines Assessing discharges from a uranium ...

Water Quality Guidelines Assessing discharges from a uranium ... Journal

Water scarcity exacerbates feral ungulate use of ephemeral savanna waterholes in northern Australia - CSIRO Publishing

View Source

Supporting Sources (21)

Additional references from the underlying research that informed this benchmark.

Preview of A Compendium of Ecological Information on Australia's Northern Tropical Rivers - Report 5 - Water quality - DCCEEW, accessed August 1, 2025,

A Compendium of Ecological Information on Australia's Northern Tropical Rivers - Report 5 - Water quality - DCCEEW, accessed August 1, 2025,

Contextual Support Journal

Threshold Indicator Taxa ANalysis and change points (dots) for the ...

View Source

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

Contextual Support GreyLiterature

Namoi River Water Quality Objectives explained - NSW Government

View Source

A review of water quality studies relevant to northern Australia - CSIRO, accessed July 21, 2025,

Contextual Support Journal

Salinity and water quality

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ANZECC & ARMCANZ (2000) guidelines - Water Quality Australia, accessed August 12, 2025

Contextual Support Government

ANZECC & ARMCANZ (2000) guidelines - Water Quality Australia

View Source

Australia's tropical savannas: vast, ancient and rich landscapes - CSIRO Research Publications Repository, accessed May 11, 2025,

Contextual Support GreyLiterature

Williams RJ, Duff GA, Bowman DMJS, Cook GD. Australia's tropical savannas: vast, ancient and rich landscapes. In: David Keith, editor/s. Australian vegetation. Cambridge, UK: Cambridge University Press; 2017. 368-388.

View Source

CLEAN BILL OF HEALTH FOR McARTHUR RIVER - Territory Q

Contextual Support Journal

CLEAN BILL OF HEALTH FOR McARTHUR RIVER - Territory Q

View Source

Deriving guideline values using reference-site data - Water Quality Australia, accessed August 12, 2025

Contextual Support Government

Water Quality Guidelines Home - Water Quality Australia

View Source

Environmental impact of the Ranger uranium mine, Alligator Rivers Region, Northern Territory, Australia - OSTI, accessed July 24, 2025

Contextual Support Journal

Revised Ranger Mine Water Quality Objectives for Magela Creek and Gulungul Creek (DOCX 1 MB) - DCCEEW

View Source

INDEPENDENT MONITOR REPORT - Glencore Australia

Contextual Support Journal

INDEPENDENT MONITOR REPORT - Glencore Australia

View Source

McArthur River Mine Annual Report Card 2023 - Northern Territory Government

Contextual Support GreyLiterature

McArthur River Mine Annual Report Card 2023 - Northern Territory Government

View Source

McArthur River Mine Independent Monitor - Water Technology

Contextual Support Journal

McArthur River Mine Independent Monitor - Water Technology

View Source

McArthur River Mining welcomes release of independent environmental report

Contextual Support GreyLiterature

McArthur River Mining welcomes release of independent environmental report

View Source

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

Contextual Support Government

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

View Source

Risk-based contaminant management: Ranger Mine case study - Australian Centre for Geomechanics

Contextual Support GreyLiterature

Risk-based contaminant management: Ranger Mine case study - Australian Centre for Geomechanics

View Source

Preview of the revised australian and new zealand water quality guidelines for toxicants: approach to their derivation and application - leusch.info

the revised australian and new zealand water quality guidelines for toxicants: approach to their derivation and application - leusch.info

Contextual Support Journal

Deriving guideline values using reference-site data - Water Quality Australia

View Source

Threats to water quality - Government of Western Australia

Contextual Support Journal

The State and Future of the Northern Territory's ... - NationBuilder

View Source

Using the ANZECC Guidelines and Water Quality Objectives in NSW, accessed August 11, 2025,

Contextual Support Journal

Reference-site data - Water Quality Australia

View Source

Waste Discharge Licence 174-13 Monitoring Report - NTEPA

Direct Evidence Journal

Waste Discharge Licence 174-13 Monitoring Report - NTEPA

View Source

Water quality | Australia state of the environment 2021, accessed August 11, 2025,

Contextual Support Government

Drivers of water quality in Afromontane-savanna rivers - Frontiers

View Source

Water quality guidelines - Queensland Environment Department, accessed August 1, 2025,

Contextual Support Government

Australian and New Zealand Guidelines for Fresh and Marine Water Quality (2000)

View Source

Water quality guidelines - Queensland Environment Department, accessed August 4, 2025,

Contextual Support Journal

Seasonal changes in water quality and macrophytes and the ...

View Source

Context

Region Australia
Biome Tropical Monsoonal Savannas
Land Use Industrial & Infrastructure Use
Assessment Pristine Reference
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 9 Jun 2026

Notes

This benchmark represents the best available condition for an industrial site in a tropical savanna, derived from decades of site-specific ecotoxicological research at the Ranger Mine, NT, to protect 99% of aquatic species in a High Ecological Value system. It functions as a conservative upper threshold for maintaining high environmental health.

Related Benchmarks

Other benchmarks in the AUS-TMS-IND-WEC family.