Water Electrical Conductivity (EC)

AUS-AIF-CON-WEC General Moderate confidence

Benchmark Value

1500 μS/cm
Direction: Lower is desirable ↓
Form: MinimumOnly

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 MaximumOnly Guard MinimumOnly Guard MaximumOnly Guard UpperThreshold Guard MinimumOnly Guard OptimalRange Guard LowerThreshold Guard MinimumOnly 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 L²21, which corresponds to an EC of approximately 1500 ³S/cm.

Metric Definition:

Water Electrical Conductivity (EC)

Benchmark Definition:

This benchmark represents an evidence-based threshold above which salinity causes broad adverse effects on aquatic biota in Australian freshwater ecosystems.

Justification:

This value serves as a robust, evidence-based upper detrimental threshold for general ecosystem integrity.

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.

Preview of Salinity - Murray–Darling Basin Authority, accessed August 11, 2025,
Salinity - Murray–Darling Basin Authority, accessed August 11, 2025,
Direct Evidence Government

Basin Plan water quality targets; Australian and New Zealand Guidelines for Fresh and Marine Water Quality (ANZG 2018/ANZECC 2000); Australia State of the Environment 2021: Inland water

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 MurrayDarling Basin (Victoria, Australia) - Canadian Science Publishing

View Source
Preview of Water and sediment quality in the Diamantina-Georgina River catchment, Lake Eyre Basin
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 Pristine Reference
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 1
  • Effective From 25 Mar 2026

Notes

Exceeding this value for prolonged periods represents a significant stressor that will lead to a loss of biodiversity and ecosystem function.

Related Benchmarks

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

800 μS/cm High
Conservation / Protected Natural Areas · Pristine Reference
MaximumOnly Active v1
300 μS/cm Moderate
Conservation / Protected Natural Areas · Pristine Reference
UpperThreshold Active v1