Water Electrical Conductivity (EC)

AUS-TDG-AGR-WEC General Moderate confidence

Benchmark Value

200 µS/cm

Thresholds: Lower: —, Upper: 200

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 15 benchmarks together — the OptimalRange form drives the primary score, while 14 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

Based on this synthesis, an EC level consistently >200 µS/cm should be considered indicative of a departure from good ecological health in these systems, with significant detrimental impacts on biodiversity and ecosystem function becoming increasingly evident as EC approaches and exceeds 350 µS/cm.

Metric Definition:

Upper detrimental ecological threshold for Water Electrical Conductivity (EC) beyond which environmental health is compromised.

Benchmark Definition:

This benchmark identifies the threshold EC level above which ecological health begins to decline in Australian Temperate Dry Woodlands & Native Grasslands agricultural crop production areas.

Justification:

Multiple lines of evidence indicate detrimental ecological effects begin above 200 µS/cm.

Sources (2)

Preview of 1.5.2.1 Surface water - Bioregional Assessments |, accessed August 11, 2025,

1.5.2.1 Surface water - Bioregional Assessments |, accessed August 11, 2025, Government

Water Quality Objectives - Border Rivers - NSW Government, accessed August 1, 2025

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Catchment Health Indicator Program Report 2021 - Upper Murrumbidgee Waterwatch, accessed August 12, 2025, Journal

Catchment Health Indicator Program Report 2021 - Upper Murrumbidgee Waterwatch

View Source

Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

Managing farm water supplies - Agriculture Victoria

Contextual Support Government

Managing farm water supplies - Agriculture Victoria

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National Guidelines for Water Quality - Department of Natural Resources and Environment Tasmania, accessed August 1, 2025,

Contextual Support

Australian and New Zealand Guidelines for Fresh and Marine Water ...

View Source

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

Contextual Support 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

Context

Region Australia
Biome Temperate Dry Woodlands & Native Grasslands
Land Use Agricultural Crop Production
Assessment Pristine Reference
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 17 Mar 2026

Notes

Significant degradation occurs as EC exceeds 350 µS/cm; values persistently above 350 µS/cm represent a degraded state. ConsistencyResolver applied 2026-03-23 00:19 UTC: UpperThreshold 200 → 200 (check: MinAboveOptimalHigh, rationale: Retain the threshold value but move it to the correct field for MaximumOnly form. The system will auto-correct the form from MinimumOnly to MaximumOnly because this is an upper degradation ceiling as per Notes.) [Auto-corrected BenchmarkForm: MinimumOnly → MaximumOnly] ConsistencyResolver applied 2026-03-23 00:19 UTC: LowerThreshold → (check: MinAboveOptimalHigh, rationale: No change needed to LowerThreshold.)

Related Benchmarks

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