Water Electrical Conductivity (EC)

AUS-TMI-AGR-WEC General Low confidence

Benchmark Value

930 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. The scoring engine uses 13 benchmarks together — the OptimalRange form drives the primary score, while 12 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary UpperThreshold Guard OptimalRange Guard MaximumOnly Guard OptimalRange Guard MinimumOnly Guard MaximumOnly Guard Point Guard MaximumOnly Guard MaximumOnly Guard Point Guard OptimalRange Guard MaximumOnly Guard

Evidence & Context

The study found that sensitive macroinvertebrate taxa decline sharply at EC levels above approximately 930 µS/cm.

Metric Definition:

Electrical Conductivity level at which sensitive macroinvertebrate communities begin to degrade in tropical streams.

Benchmark Definition:

This benchmark marks the ecological tipping point for water electrical conductivity indicating significant aquatic ecosystem degradation in the biome.

Justification:

Based on ecotoxicological studies from tropical streams showing community shifts at this threshold.

Sources (1)

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, Journal

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

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Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

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

Contextual Support Journal

Australian and New Zealand Guidelines for Fresh and Marine Water ...

View Source

Preview of Proserpine River, Whitsunday Island and O'Connell River Basins Environmental Values and Water Quality Objectives - Queensland Environment Department, accessed August 2, 2025,

Proserpine River, Whitsunday Island and O'Connell River Basins Environmental Values and Water Quality Objectives - Queensland Environment Department, accessed August 2, 2025,

Regulatory Framework Journal

Bioregional Assessment of the Clarence-Moreton bioregion, which includes the Richmond River basin

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VOLUME 1 WATER RESOURCES OF THE TIWI ... - Tiwi Land Council

Contextual Support Government

VOLUME 1 WATER RESOURCES OF THE TIWI ... - Tiwi Land Council

View Source

Context

Region Australia
Biome Tropical & Subtropical Maritime Islands
Land Use Agricultural Crop Production
Assessment Not Stated
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 10 Jun 2026

Notes

Exceeding this EC level indicates active degradation and loss of sensitive aquatic species. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TMI-AGR-WEC family.