Water Electrical Conductivity (EC)

AUS-AIF-CON-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. The scoring engine uses 9 benchmarks together — the OptimalRange form drives the primary score, while 8 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

A comprehensive review of salinity effects on Australian freshwater ecosystems suggests that broad, adverse effects on aquatic biota become apparent as salinity exceeds 1000 mg L−1, which corresponds to an EC of approximately 1500 µS/cm.

Metric Definition:

Water Electrical Conductivity (EC) threshold for adverse effects on aquatic biota

Benchmark Definition:

This benchmark represents the upper electrical conductivity level above which adverse ecological effects occur in freshwater ecosystems of arid inland floodplains.

Justification:

This value is supported by ecological studies indicating significant stress and biodiversity loss above this EC level.

Sources (1)

Preview of (PDF) Water quality in two Australian dryland rivers: spatial and temporal variability and the role of flow - ResearchGate, accessed July 30, 2025,

(PDF) Water quality in two Australian dryland rivers: spatial and temporal variability and the role of flow - ResearchGate, accessed July 30, 2025,

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

View Source

Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

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

Direct Evidence Government

Salinity | Murray–Darling Basin Authority

View Source

Preview of Validating species sensitivity distributions using salinity tolerance of riverine macroinvertebrates in the southern MurrayDarling Basin (Victoria, Australia) - Canadian Science Publishing

Validating species sensitivity distributions using salinity tolerance of riverine macroinvertebrates in the southern MurrayDarling Basin (Victoria, Australia) - Canadian Science Publishing

Direct Evidence Journal

Validating species sensitivity distributions using salinity tolerance of riverine macroinvertebrates in the southern Murray–Darling Basin (Victoria, Australia)

View Source

Water and sediment quality in the Diamantina-Georgina River catchment, Lake Eyre Basin

Direct Evidence Journal

Water quality in the Georgina-Diamantina River catchment

View Source

Context

Region Australia
Biome Arid Inland Floodplains & Ephemeral River Systems
Land Use Conservation / Protected Natural Areas
Assessment Conservation Target
Evidence Type DegradationThreshold

Lifecycle

Status Retired
Version 2
Effective From 10 Jun 2026
Effective To 10 Jun 2026

Notes

Exceeding 1500 µS/cm represents a significant stressor leading to loss of biodiversity and ecosystem function. Pipeline quarantine: Lower confidence than existing active benchmark v1 (High). Accepted by operator on 2026-06-10 11:37 UTC — superseded v2 (#3093)

Related Benchmarks

Other benchmarks in the AUS-AIF-CON-WEC family.