Water Electrical Conductivity (EC)

AUS-TSR-LVG-WEC General Moderate confidence

Benchmark Value

750 μS/cm

Direction: Lower is desirable ↓

Form: MaximumOnly

Scoring Curve

Scoring curve unavailable

The scoring engine could not generate a curve for this benchmark context. The primary form is CompositeFramework, but the benchmark data may be missing required fields (e.g., optimal range bounds for an OptimalRange benchmark). This is typically a data quality issue in the benchmark pipeline.

Contributing Benchmarks

CompositeFramework Primary OptimalRange Guard OptimalRange Guard MaximumOnly Guard OptimalRange Guard MaximumOnly Guard MaximumOnly Guard OptimalRange Guard MaximumOnly Guard MaximumOnly Guard Point Guard Point Guard MaximumOnly Guard MaximumOnly Guard

Evidence & Context

A Victorian study identified a general tolerance limit for mayfly nymphs of 750 μS/cm.

Metric Definition:

Electrical Conductivity (EC) level at which chronic sub-lethal effects on sensitive bio-indicators begin

Benchmark Definition:

This benchmark marks the upper electrical conductivity level at which chronic sub-lethal effects begin to appear in sensitive aquatic species, indicating the start of ecological harm.

Justification:

Based on studies of physiological tolerance of sensitive native species such as mayflies, critical bio-indicators of aquatic ecosystem health.

Sources (1)

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

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

Salinity Tolerances of Freshwater Macroinvertebrates

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Supporting Sources (4)

Additional references from the underlying research that informed this benchmark.

Accessory Publication Relative salinity tolerance of macroinvertebrates from the Barwon River, Victoria, Australia

Direct Evidence Journal

Pine Creek, near Dutton 2010 Aquatic Ecosystem Condition Report - EPA SA

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Preview of Effect of reduced grazing pressure on sediment and nutrient yields in savanna rangeland streams draining to the Great Barrier Reef - CSIRO Research Publications Repository

Effect of reduced grazing pressure on sediment and nutrient yields in savanna rangeland streams draining to the Great Barrier Reef - CSIRO Research Publications Repository

Direct Evidence Journal

(PDF) A review of the salt sensitivity of the Australian freshwater biota

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Sub-lethal and chronic salinity tolerances of three freshwater insects ...

Contextual Support Journal

Sub-lethal and chronic salinity tolerances of three freshwater insects ...

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Tully River, Murray River and Hinchinbrook Island Basins Environmental Values and Water Quality Objectives

Direct Evidence Journal

Environmental Protection (Water and Wetland Biodiversity) Policy 2019: Tully, Murray and Hinchinbrook Island River Basins Environmental Values and Water Quality Objectives

View Source

Context

Region Australia
Biome Tropical & Subtropical Rainforests
Land Use Livestock Grazing & Pasture
Assessment Not Stated
Evidence Type DegradationThreshold

Lifecycle

Status Superseded
Version 1
Effective From 5 Jun 2026
Effective To 5 Jun 2026

Notes

Represents the scientifically defensible start of direct ecological detriment due to elevated EC. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TSR-LVG-WEC family.