Water Electrical Conductivity (EC)

AUS-AIF-CON-WEC General High confidence

Benchmark Value

800 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 value of < 800 µS/cm serves as a robust and defensible benchmark.

Metric Definition:

Water Electrical Conductivity (EC) in surface water of arid inland floodplains

Benchmark Definition:

This benchmark represents the upper limit of water electrical conductivity in surface waters of arid inland floodplains, indicating salinity levels protective of aquatic biodiversity during productive phases.

Justification:

The benchmark is based on synthesis of evidence from the Georgina-Diamantina catchment described as having 'low salinity', the MDBA definition of 'low salinity' as < 800 µS/cm, and biological studies showing macroinvertebrate richness declines above 300-500 µS/cm.

Sources (3)

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

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

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 Journal

Water quality in the Georgina-Diamantina River catchment

View Source

Supporting Sources (1)

Additional references from the underlying research that informed this benchmark.

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,

Direct Evidence

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

View Source

Context

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

Lifecycle

Status Superseded
Version 1
Effective From 10 Jun 2026
Effective To 10 Jun 2026

Notes

The benchmark represents the upper limit of the optimal range for high ecological health in Australia's arid inland river systems. It is protective of aquatic biodiversity and aligns with management definitions.

Related Benchmarks

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