Water Electrical Conductivity (EC)

AUS-TSR-AGR-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 13 benchmarks together — the OptimalRange form drives the primary score, while 12 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

Levels above 1500 µS/cm are associated with broad-scale adverse effects on Australian freshwater biota.

Metric Definition:

Upper threshold for Water Electrical Conductivity (EC) indicating severe ecological degradation.

Benchmark Definition:

This benchmark defines the severe upper threshold for Water Electrical Conductivity (EC) in tropical rainforest agricultural streams, above which broad-scale adverse biological effects occur.

Justification:

Supported by broad-scale research on Australian freshwater ecosystems.

Sources (1)

(PDF) Effects of increasing salinity on freshwater ecosystems in Australia - ResearchGate, accessed August 11, 2025, GreyLiterature

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

View Source

Supporting Sources (2)

Additional references from the underlying research that informed this benchmark.

Preview of Ecology of streams in a biogeographic isolate—the Queensland Wet Tropics, Australia | Freshwater Science: Vol 34, No 2, accessed July 22, 2025,

Ecology of streams in a biogeographic isolate—the Queensland Wet Tropics, Australia | Freshwater Science: Vol 34, No 2, accessed July 22, 2025,

Direct Evidence Journal

Australian and New Zealand Guidelines for Fresh and Marine Water Quality (ANZECC/ARMCANZ)

View Source

Johnstone River Basin Environmental Values and Water Quality ...

Direct Evidence Journal

Johnstone River Basin Environmental Values and Water Quality ...

View Source

Context

Region Australia
Biome Tropical & Subtropical Rainforests
Land Use Agricultural Crop Production
Assessment Not Stated
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 2
Effective From 10 Jun 2026

Notes

At this level, major shifts in community composition and loss of salt-sensitive taxa occur. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

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