Water Electrical Conductivity (EC)

AUS-TGP-AGR-WEC General Moderate confidence

Benchmark Value

400 µS/cm

Thresholds: Lower: 400, Upper: —

Direction: Lower is desirable ↓

Form: LowerThreshold

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

Evidence suggests that using water with an EC below approximately 400 µS/cm can lead to the stripping of essential cations from soil aggregates, causing soil structural degradation, surface sealing, and reduced water infiltration.

Metric Definition:

Electrical Conductivity (EC) level in irrigation water below which soil structural degradation occurs.

Benchmark Definition:

Lower critical threshold for EC in irrigation water to prevent soil structural damage.

Justification:

This threshold is based on agronomic evidence that hypo-saline water below this EC causes soil degradation.

Sources (1)

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

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

Supporting Sources (1)

Additional references from the underlying research that informed this benchmark.

Effects of increasing salinity on freshwater ecosystems in Australia - CSIRO Publishing, accessed August 28, 2025,

Direct Evidence Journal

Effects of increasing salinity on freshwater ecosystems in Australia - CSIRO Publishing

View Source

Context

Region Australia
Biome Temperate Grassy Woodlands & Plains
Land Use Agricultural Crop Production
Assessment Pristine Reference
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 24 Mar 2026

Notes

Relevant specifically to irrigated agricultural crop production land use. No upper detrimental threshold — higher values are always better up to natural saturation.

Related Benchmarks

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