Water Turbidity

AUS-AMR-CON-WTU General Moderate confidence

Benchmark Value

5 NTU
Range: 2 to 25 NTU
Thresholds: Lower: —, Upper: 25
Optimal Range: 2 to 25
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 MaximumOnly Guard OptimalRange Guard MaximumOnly Guard

Evidence & Context

A benchmark of < 5 NTU is proposed to represent this "best-on-offer" condition.

Metric Definition:

Water Turbidity

Benchmark Definition:

Water turbidity measures the clarity of water caused by suspended particles. This benchmark represents the best water clarity condition expected in protected arid upland catchments during non-flood periods.

Justification:

This benchmark represents the best available condition for baseflow in ephemeral and intermittent streams within protected arid uplands. It is derived by synthesizing the ANZECC 2000 guideline for upland rivers (2–25 NTU) with qualitative evidence from the source report, which links the highest ecological condition ("Good") to protected, stable upper catchments in the Flinders Ranges where low siltation is expected.

Sources (1)

Preview of SA Arid Lands Landscape Regional Summary 2022 Aquatic ..., accessed July 30, 2025,
SA Arid Lands Landscape Regional Summary 2022 Aquatic ..., accessed July 30, 2025, Government

(PDF) Effects of increasing salinity on freshwater ecosystems in ..., accessed July 31, 2025,

View Source

Supporting Sources (20)

Additional references from the underlying research that informed this benchmark.

Preview of 5.5 Turbidity | Monitoring & Assessment - EPA Archives, accessed July 30, 2025,
5.5 Turbidity | Monitoring & Assessment - EPA Archives, accessed July 30, 2025,
Contextual Support Government

5.5 Turbidity | Monitoring & Assessment - EPA Archives, accessed August 3, 2025

View Source
Preview of An Introduction to the Australian and New Zealand Guidelines for Fresh and Marine Water Quality - EPA, accessed May 11, 2025,
An Introduction to the Australian and New Zealand Guidelines for Fresh and Marine Water Quality - EPA, accessed May 11, 2025,
Contextual Support Journal

National Guidelines for Water Quality - Department of Natural Resources and Environment Tasmania, accessed August 3, 2025

View Source
Preview of ANZECC & ARMCANZ (2000) guidelines - Water Quality Australia, accessed August 12, 2025
ANZECC & ARMCANZ (2000) guidelines - Water Quality Australia, accessed August 12, 2025
Contextual Support Government

ANZECC & ARMCANZ (2000) guidelines - Water Quality Australia

View Source
Preview of Assessing Water Quality - Secondary Education Years 9 to 12 - Upper Murrumbidgee Waterwatch, accessed August 12, 2025,
Assessing Water Quality - Secondary Education Years 9 to 12 - Upper Murrumbidgee Waterwatch, accessed August 12, 2025,
Contextual Support Journal

Assessing water quality - ACT Waterwatch

View Source
Preview of Characterising the relationship between water quality and water quantity, accessed August 3, 2025
Characterising the relationship between water quality and water quantity, accessed August 3, 2025
Contextual Support Government

Characterising the relationship between water quality and water quantity, accessed August 3, 2025

View Source
Preview of Clarity and colour - WetlandInfo, accessed August 12, 2025,
Clarity and colour - WetlandInfo, accessed August 12, 2025,
Contextual Support Government

Determining Tipping Points and Responses of Macroinvertebrate Traits to Abiotic Factors in Support of River Management - PMC - PubMed Central, accessed July 25, 2025,

View Source
Preview of Development of regional water quality and catchment guidelines for the conservation of aquatic ecosystems - NSW Environment Protection Authority, accessed July 30, 2025,
Development of regional water quality and catchment guidelines for the conservation of aquatic ecosystems - NSW Environment Protection Authority, accessed July 30, 2025,
Contextual Support Journal

Defining reference condition for South Australian streams ... - EPA SA, accessed August 3, 2025

View Source
Preview of Guidance document for assessing and managing water quality in temporary waters, accessed July 16, 2025,
Guidance document for assessing and managing water quality in temporary waters, accessed July 16, 2025,
Contextual Support Journal

Guidance document for assessing and managing water quality in temporary waters, accessed July 10, 2025,

View Source
Preview of Hydrological Assessment and Analysis of the Diamantina River Catchment, South Australia - Department for Environment and Water, accessed August 3, 2025
Hydrological Assessment and Analysis of the Diamantina River Catchment, South Australia - Department for Environment and Water, accessed August 3, 2025
Contextual Support Journal

Hydrological Assessment and Analysis of the Diamantina River Catchment, South Australia - Department for Environment and Water, accessed August 3, 2025

View Source
Preview of Identification of Groundwater Potential Recharge Zones in Flinders Ranges, South Australia Using Remote Sensing, GIS, and MIF Techniques - MDPI, accessed August 3, 2025
Identification of Groundwater Potential Recharge Zones in Flinders Ranges, South Australia Using Remote Sensing, GIS, and MIF Techniques - MDPI, accessed August 3, 2025
Contextual Support Journal

Identification of Groundwater Potential Recharge Zones in Flinders Ranges, South Australia Using Remote Sensing, GIS, and MIF Techniques - MDPI, accessed August 3, 2025

View Source
Preview of Monitoring and reporting on water quality - Environment and Heritage, accessed August 5, 2025
Monitoring and reporting on water quality - Environment and Heritage, accessed August 5, 2025
Contextual Support

Australian and New Zealand guidelines for fresh and marine water quality, accessed August 3, 2025

View Source
Preview of National Guidelines for Water Quality - Department of Natural Resources and Environment Tasmania, accessed August 1, 2025,
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
Preview of The aquatic plant communities of the Pilbara ... - CSIRO Publishing, accessed July 27, 2025,
The aquatic plant communities of the Pilbara ... - CSIRO Publishing, accessed July 27, 2025,
Contextual Support Journal

The aquatic plant communities of the Pilbara region of Western Australia: a region of arid zone wetland diversity - CSIRO Publishing, accessed August 3, 2025

View Source
Preview of The aquatic plant communities of the Pilbara region of Western Australia: a region of arid zone wetland diversity - CSIRO PUBLISHING | Pacific Conservation Biology, accessed July 27, 2025,
The aquatic plant communities of the Pilbara region of Western Australia: a region of arid zone wetland diversity - CSIRO PUBLISHING | Pacific Conservation Biology, accessed July 27, 2025,
Methodology Source Journal

Guidance document for assessing and managing water quality in temporary waters, accessed August 3, 2025

View Source
Preview of Turbidity | Australian Drinking Water Guidelines - NHMRC, accessed August 11, 2025,
Turbidity | Australian Drinking Water Guidelines - NHMRC, accessed August 11, 2025,
Contextual Support Government

Australian Drinking Water Guidelines

View Source
Preview of Water quality - Defining reference condition for South Australian ..., accessed August 12, 2025
Water quality - Defining reference condition for South Australian ..., accessed August 12, 2025
Contextual Support Journal

What's wrong with the Australian River Assessment System (AUSRIVAS)?, accessed August 3, 2025

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

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

View Source
Preview of Water Quality Objectives - Border Rivers - NSW Government, accessed August 12, 2025
Water Quality Objectives - Border Rivers - NSW Government, accessed August 12, 2025
Contextual Support Government

(PDF) Impact of mitigated forestry activities on turbidity: assessing ..., accessed August 10, 2025

View Source
Preview of What´s wrong with the Australian River Assessment System (AUSRIVAS)? - CSIRO Publishing, accessed August 3, 2025
What´s wrong with the Australian River Assessment System (AUSRIVAS)? - CSIRO Publishing, accessed August 3, 2025
Contextual Support Journal

What´s wrong with the Australian River Assessment System (AUSRIVAS)? - CSIRO Publishing, accessed August 3, 2025

View Source
Preview of Why Measure Turbidity? - Montclair State University, accessed August 12, 2025,
Why Measure Turbidity? - Montclair State University, accessed August 12, 2025,
Contextual Support GreyLiterature

Feral horses (Equus caballus) increase suspended sediment in subalpine streams, accessed August 3, 2025

View Source

Context

  • Region Australia
  • Biome Arid Mountain Ranges & Uplands
  • Land Use Conservation / Protected Natural Areas
  • Assessment Conservation Target
  • Evidence Type TargetCondition

Lifecycle

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

Notes

Lower turbidity is consistently better for ecosystem health. A persistent baseflow turbidity exceeding 25 NTU is considered a detrimental threshold indicating departure from a high-health conservation state.