Water Electrical Conductivity (EC)

AUS-TMI-AGR-WEC General Moderate confidence

Benchmark Value

No specific value — see range

Range: 180 to 780 µS/cm

Optimal Range: 180 to 780

Direction: Higher is desirable ↑

Form: OptimalRange

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 15 benchmarks together — the OptimalRange form drives the primary score, while 14 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

For waters designated as 'Whitsunday Islands fresh waters in HEV2384 areas (High Ecological Value),' the policy sets an ambient baseflow EC objective as a range of 180–260–780 µS/cm.

Metric Definition:

Ambient baseflow Electrical Conductivity (EC) objective for High Ecological Value waters.

Benchmark Definition:

This benchmark defines the regulatory water quality objective range for electrical conductivity in High Ecological Value waters of the Whitsunday Islands, reflecting managed targets that accept some deviation from natural baselines.

Justification:

This objective is based on mainland analogue data due to lack of island-specific data and represents a managed target accepting some deviation from the natural baseline.

Sources (1)

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, Journal

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

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Supporting Sources (3)

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,

Direct Evidence Journal

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

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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 Quality (ANZG)

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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

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Context

Region Australia
Biome Tropical & Subtropical Maritime Islands
Land Use Agricultural Crop Production
Assessment Pristine Reference
Evidence Type RegulatoryTrigger

Lifecycle

Status Active
Version 1
Effective From 25 Mar 2026

Notes

This value is an order of magnitude higher than the natural baseline on the Tiwi Islands, highlighting the difference between natural and managed benchmarks.

Related Benchmarks

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