Water Electrical Conductivity (EC)

AUS-AKW-CON-WEC General Moderate confidence

Benchmark Value

1000 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 6 benchmarks together — the OptimalRange form drives the primary score, while 5 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary MaximumOnly Guard MaximumOnly Guard OptimalRange Guard MinimumOnly Guard OptimalRange Guard

Evidence & Context

The benchmark represents the typical fresh condition (< 1,000 μS/cm) of groundwater that defines the "Karst Springs and Associated Alkaline Fens," a threatened, groundwater-dependent ecological community in a South Australian karstic landscape.

Metric Definition:

Water Electrical Conductivity (EC) in groundwater of Arid Karstic Woodlands & Shrublands biome

Benchmark Definition:

This benchmark defines the maximum electrical conductivity level of groundwater in Arid Karstic Woodlands & Shrublands under conservation, representing fresh conditions typical of high-health karstic systems.

Justification:

This value is selected as the most direct, ecologically-defined reference for a high-health karstic system in a protected context. It aligns well with data from other arid and semi-arid systems where high-quality "freshwater lenses" are defined as having < 1,000 mg/L TDS (equivalent to ~1,538μS/cm).

Sources (2)

Preview of Conservation Advice for the Karst springs and associated alkaline fens of the Naracoorte Coastal Plain Bioregion

Conservation Advice for the Karst springs and associated alkaline fens of the Naracoorte Coastal Plain Bioregion Journal

Conservation Advice for the Karst springs and associated alkaline fens of the Naracoorte Coastal Plain Bioregion

Preview of DEPARTMENT OF MINES AND ENERGY SOUTH AUSTRALIA REPORT BOOK 96/10 MUSGRAVE PROCLAIMED WELLS AREA GROUNDWATER ASSESSMENT by A J L - NET

DEPARTMENT OF MINES AND ENERGY SOUTH AUSTRALIA REPORT BOOK 96/10 MUSGRAVE PROCLAIMED WELLS AREA GROUNDWATER ASSESSMENT by A J L - NET Journal

Water Affecting Activity Control Policy, accessed July 27, 2025

Supporting Sources (17)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Subterranean Fauna of the Arid Zone - ResearchGate, accessed July 27, 2025,

(PDF) Subterranean Fauna of the Arid Zone - ResearchGate, accessed July 27, 2025,

Contextual Support GreyLiterature

How to Calculate Electrical Conductivity From TDS? - Rika Sensor, accessed July 27, 2025

Preview of Conductivity, TDS, Salinity, Resistivity - apera instruments, accessed July 20, 2025,

Conductivity, TDS, Salinity, Resistivity - apera instruments, accessed July 20, 2025,

Methodology Source Journal

Geological Control upon Groundwater Flow and Major Ion Chemistry with Influence on Basin Management in a Coastal Aquifer, South Australia - Scientific Research Publishing, accessed July 27, 2025

Preview of CONSULTATION INFORMATION PACK Establishing baseline data for the conservation of Koonalda Cave, accessed July 27, 2025,

CONSULTATION INFORMATION PACK Establishing baseline data for the conservation of Koonalda Cave, accessed July 27, 2025,

Contextual Support GreyLiterature

CONSULTATION INFORMATION PACK Establishing baseline data for the conservation of Koonalda Cave, accessed July 27, 2025

Preview of Eyre Peninsula Groundwater Dependent Ecosystem Scoping Study - Department for Environment and Water, accessed July 27, 2025,

Eyre Peninsula Groundwater Dependent Ecosystem Scoping Study - Department for Environment and Water, accessed July 27, 2025,

Contextual Support Journal

Eyre Peninsula Groundwater Dependent Ecosystem Scoping Study - Department for Environment and Water, accessed July 27, 2025

Preview of Geology of Australia | EBSCO Research Starters, accessed July 27, 2025,

Geology of Australia | EBSCO Research Starters, accessed July 27, 2025,

Contextual Support GreyLiterature

GSA Today - The evolution of end-member continental waters: The origin of acidity in southern Western Australia, accessed July 27, 2025

Preview of Guide to New South Wales Karst and Caves - Environment and Heritage, accessed July 25, 2025,

Guide to New South Wales Karst and Caves - Environment and Heritage, accessed July 25, 2025,

Contextual Support

The Nullarbor deserves better protection - La Trobe University, accessed July 27, 2025

Preview of Investigation on the groundwater resources of the South Eyre Peninsula, South Australia, determined from laterally constrained inversion of tempest data - ResearchGate, accessed July 27, 2025,

Investigation on the groundwater resources of the South Eyre Peninsula, South Australia, determined from laterally constrained inversion of tempest data - ResearchGate, accessed July 27, 2025,

Contextual Support GreyLiterature

Investigation on the groundwater resources of the South Eyre Peninsula, South Australia, determined from laterally constrained inversion of tempest data - ResearchGate, accessed July 27, 2025

Preview of Karst and agriculture in Australia - Digital Commons @ USF, accessed July 27, 2025,

Karst and agriculture in Australia - Digital Commons @ USF, accessed July 27, 2025,

Contextual Support Journal

Soil Management Systems to Overcome Multiple Constraints for Dryland Crops on Deep Sands in a Water Limited Environment on the South Coast of Western Australia - MDPI

Preview of Nullarbor Plain - Wikipedia, accessed July 25, 2025,

Nullarbor Plain - Wikipedia, accessed July 25, 2025,

Contextual Support GreyLiterature

Nullarbor Plain - Wikipedia, accessed July 24, 2025

Preview of Palaeovalley Groundwater Resources in Arid and Semi-Arid Australia, accessed July 27, 2025,

Palaeovalley Groundwater Resources in Arid and Semi-Arid Australia, accessed July 27, 2025,

Contextual Support Journal

Palaeovalley Groundwater Resources in Arid and Semi-Arid Australia, accessed July 27, 2025

Preview of Salinity tolerance of stygofauna at Mulga Downs Iron Ore Mine - EPA WA, accessed July 27, 2025,

Salinity tolerance of stygofauna at Mulga Downs Iron Ore Mine - EPA WA, accessed July 27, 2025,

Contextual Support Journal

Salinity tolerance of stygofauna at Mulga Downs Iron Ore Mine - EPA WA, accessed July 27, 2025

Preview of TDS and EC Conversion - Snowate, accessed July 27, 2025,

TDS and EC Conversion - Snowate, accessed July 27, 2025,

Methodology Source GreyLiterature

TDS and EC Conversion - Snowate, accessed July 27, 2025

Preview of The Nullarbor deserves better protection - La Trobe University, accessed July 26, 2025,

The Nullarbor deserves better protection - La Trobe University, accessed July 26, 2025,

Contextual Support GreyLiterature

Nullarbor Plains Xeric Shrublands | One Earth, accessed July 27, 2025

Preview of Total dissolved solids | Australian Drinking Water Guidelines - NHMRC, accessed July 27, 2025,

Total dissolved solids | Australian Drinking Water Guidelines - NHMRC, accessed July 27, 2025,

Contextual Support Government

Australian and New Zealand Guidelines for Fresh and Marine Water Quality

Preview of Water Data SA – Available Data - WaterConnect, accessed July 27, 2025,

Water Data SA – Available Data - WaterConnect, accessed July 27, 2025,

Contextual Support Journal

Conservation Advice for the Karst springs and associated alkaline fens of the Naracoorte Coastal Plain Bioregion, accessed July 27, 2025

Preview of Water in the region - Landscape South Australia - Alinytjara Wilurara, accessed July 27, 2025,

Water in the region - Landscape South Australia - Alinytjara Wilurara, accessed July 27, 2025,

Contextual Support Government

Falls in groundwater for southern Eyre Peninsula in South Australia force 2024 decision for plant to desalinate seawater | Adelaide AZ, accessed July 27, 2025

Preview of www.dcceew.gov.au, accessed July 27, 2025,

www.dcceew.gov.au, accessed July 27, 2025,

Contextual Support

www.dcceew.gov.au, accessed July 27, 2025

Context

Region Australia
Biome Arid Karstic Woodlands & Shrublands
Land Use Conservation / Protected Natural Areas
Assessment Pristine Reference
Evidence Type ReferenceCondition

Lifecycle

Status Superseded
Version 1
Effective From 4 Jun 2026
Effective To 4 Jun 2026

Notes

Confidence is rated 'Moderate' rather than 'High' because the primary source is from a semi-arid/Mediterranean climate, not a truly arid one like the Nullarbor Plain. There is no evidence for a lower critical threshold; the primary conservation goal is to prevent salinity from rising above this natural, optimal range. No upper detrimental threshold — higher values are harmful beyond this point.

Related Benchmarks

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