Water Electrical Conductivity (EC)

AUS-TMS-URB-WEC General High confidence

Benchmark Value

No specific value — see range
Range: 20 to 200 µS/cm
Optimal Range: 20 to 200
Direction: Higher is desirable ↑
Form: OptimalRange

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 14 benchmarks together — the OptimalRange form drives the primary score, while 13 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary MaximumOnly Guard MaximumOnly Guard LowerThreshold Guard UpperThreshold Guard MaximumOnly Guard MaximumOnly Guard OptimalRange Guard UpperThreshold Guard LowerThreshold Guard OptimalRange Guard MaximumOnly Guard OptimalRange Guard UpperThreshold Guard

Evidence & Context

The proposed optimal range for Electrical Conductivity is 20 – 200 µS/cm.

Metric Definition:

Water Electrical Conductivity (EC) in freshwater rivers and streams

Benchmark Definition:

Optimal functional range of Water Electrical Conductivity (EC) for maintaining high ecological condition in freshwater streams in the tropical monsoonal savanna biome under urban and developed land use.

Justification:

Systems maintained within this 20–200 µS/cm range by best-practice urban water management are operating within the bounds of natural variability for this biome. They are well clear of the detrimental upper threshold of 1500 µS/cm and avoid the potential physiological stress associated with over-dilution.

Sources (1)

Preview of Water Quality Objectives for the Darwin Harbour Region - Background Document - Department of Lands, Planning and Environment, accessed July 16, 2025,
Water Quality Objectives for the Darwin Harbour Region - Background Document - Department of Lands, Planning and Environment, accessed July 16, 2025, Journal

Water Quality Objectives for the Darwin Harbour Region - Background Document - Department of Lands, Planning and Environment

View Source

Supporting Sources (2)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Effects of increasing salinity on freshwater ecosystems in Australia - ResearchGate, accessed August 11, 2025,
(PDF) Effects of increasing salinity on freshwater ecosystems in Australia - ResearchGate, accessed August 11, 2025,
Direct Evidence Journal

Effects of increasing salinity on freshwater ecosystems in Australia - ResearchGate

View Source
Preview of Water quality guidelines - Queensland Environment Department, accessed August 1, 2025,
Water quality guidelines - Queensland Environment Department, accessed August 1, 2025,
Direct Evidence Government

Australian and New Zealand Guidelines for Fresh and Marine Water Quality (2000)

View Source

Context

  • Region Australia
  • Biome Tropical Monsoonal Savannas
  • Land Use Urban & Developed Use
  • Assessment Pristine Reference
  • Evidence Type HealthyOperationalRange

Lifecycle

  • Status Active
  • Version 1
  • Effective From 19 Mar 2026

Notes

This range constitutes the target for achieving and maintaining high environmental health in the face of urban development.

Related Benchmarks

Other benchmarks in the AUS-TMS-URB-WEC family.

200 µS/cm High
Urban & Developed Use · Pristine Reference
MaximumOnly Active v1
1500 µS/cm High
Urban & Developed Use · Pristine Reference
UpperThreshold Active v1
20 µS/cm High
Urban & Developed Use · Pristine Reference
LowerThreshold Active v1