Water Turbidity

AUS-TSR-CON-WTU General High confidence

Benchmark Value

5 NTU
Thresholds: Lower: —, Upper: 5
Direction: Lower is desirable ↓
Form: UpperThreshold

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 8 benchmarks together — the OptimalRange form drives the primary score, while 7 guard(s) constrain the result.

Evidence & Context

The report identifies a robust upper detrimental threshold at approximately 5 NTU.

Metric Definition:

Upper detrimental turbidity threshold beyond which severe ecological stress and degradation occur in aquatic ecosystems of the Australian tropical rainforest biome.

Benchmark Definition:

This threshold marks the turbidity level above which severe ecological stress and degradation occur in aquatic ecosystems of protected tropical rainforests in Australia.

Justification:

Supported by convergent evidence from studies on Great Barrier Reef corals and freshwater macroinvertebrates showing severe stress and declines in sensitive species above this turbidity level.

Sources (2)

Preview of Determining Tipping Points and Responses of Macroinvertebrate Traits to Abiotic Factors in Support of River Management - PubMed Central, accessed July 16, 2025,
Determining Tipping Points and Responses of Macroinvertebrate Traits to Abiotic Factors in Support of River Management - PubMed Central, accessed July 16, 2025, Journal

Determining Tipping Points and Responses of Macroinvertebrate Traits to Abiotic Factors in Support of River Management. Water, 15(8), 1589.

View Source
Preview of Temporal dynamics in coral bioindicators for water quality on coastal coral reefs of the Great Barrier Reef - CSIRO Publishing, accessed July 22, 2025
Temporal dynamics in coral bioindicators for water quality on coastal coral reefs of the Great Barrier Reef - CSIRO Publishing, accessed July 22, 2025 Journal

Temporal dynamics in coral bioindicators for water quality on coastal coral reefs of the Great Barrier Reef - CSIRO Publishing, accessed July 22, 2025

View Source

Supporting Sources (26)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Water Quality Degradation of Coastal Waterways in the Wet Tropics, Australia, accessed August 2, 2025,
(PDF) Water Quality Degradation of Coastal Waterways in the Wet Tropics, Australia, accessed August 2, 2025,
Contextual Support

Requirements for graziers | Environment, land and water ..., accessed July 19, 2025,

View Source
Preview of A Compendium of Ecological Information on Australia's Northern Tropical Rivers - Report 5 - Water quality - DCCEEW, accessed August 1, 2025,
A Compendium of Ecological Information on Australia's Northern Tropical Rivers - Report 5 - Water quality - DCCEEW, accessed August 1, 2025,
Contextual Support Journal

Threshold Indicator Taxa ANalysis and change points (dots) for the ...

View Source
Preview of Australian and New Zealand Guidelines for Fresh and Marine Water Quality (2000) - V, accessed July 22, 2025
Australian and New Zealand Guidelines for Fresh and Marine Water Quality (2000) - V, accessed July 22, 2025
Contextual Support Journal

1.5.2.1 Surface water - Bioregional Assessments |

View Source
Preview of Characterising the relationship between water quality and water quantity, accessed August 5, 2025
Characterising the relationship between water quality and water quantity, accessed August 5, 2025
Contextual Support Journal

Report Card 2022-23 - EPA Victoria

View Source
Preview of Full article: Relationships between algal primary productivity and environmental variables in tropical floodplain wetlands - Taylor & Francis Online, accessed August 2, 2025,
Full article: Relationships between algal primary productivity and environmental variables in tropical floodplain wetlands - Taylor & Francis Online, accessed August 2, 2025,
Contextual Support

Full article: Relationships between algal primary productivity and environmental variables in tropical floodplain wetlands - Taylor & Francis Online, accessed August 2, 2025,

View Source
Preview of Marine ecosystem impacts - Reef 2050 Water Quality Improvement Plan, accessed August 1, 2025,
Marine ecosystem impacts - Reef 2050 Water Quality Improvement Plan, accessed August 1, 2025,
Contextual Support Journal

TERN: Terrestrial Ecosystem Research Network - The Waite, accessed July 27, 2025,

View Source
Preview of Queensland Reef Water Quality Program | Environment, land and water, accessed August 3, 2025,
Queensland Reef Water Quality Program | Environment, land and water, accessed August 3, 2025,
Contextual Support Government

Queensland Reef Water Quality Program | Environment, land and water, accessed August 2, 2025,

View Source
Preview of Queensland Water Quality Guidelines 2009, accessed July 21, 2025,
Queensland Water Quality Guidelines 2009, accessed July 21, 2025,
Contextual Support Journal

Queensland Water Quality Guidelines 2009

View Source
Preview of Reef Water Quality Report Card 2020 Great Barrier Reef Marine Monitoring Program Methods, accessed July 22, 2025
Reef Water Quality Report Card 2020 Great Barrier Reef Marine Monitoring Program Methods, accessed July 22, 2025
Contextual Support Journal

Reef Water Quality Report Card 2020 Great Barrier Reef Marine Monitoring Program Methods, accessed July 22, 2025

View Source
Preview of Regional report cards | Reef 2050 Water Quality Improvement Plan, accessed July 21, 2025,
Regional report cards | Reef 2050 Water Quality Improvement Plan, accessed July 21, 2025,
Contextual Support Government

Regional report cards | Reef 2050 Water Quality Improvement Plan, accessed July 21, 2025,

View Source
Preview of REPORT CARD 2024 - Wet Tropics Waterways, accessed July 22, 2025
REPORT CARD 2024 - Wet Tropics Waterways, accessed July 22, 2025
Contextual Support Journal

REPORT CARD 2024 - Wet Tropics Waterways, accessed July 22, 2025

View Source
Preview of Report Card Explainer - Reef 2050 Water Quality Improvement Plan, accessed August 2, 2025,
Report Card Explainer - Reef 2050 Water Quality Improvement Plan, accessed August 2, 2025,
Contextual Support Journal

Report Card Explainer - Reef 2050 Water Quality Improvement Plan, accessed August 2, 2025,

View Source
Preview of Results - Wet Tropics Waterways, accessed July 22, 2025
Results - Wet Tropics Waterways, accessed July 22, 2025
Contextual Support

Results - Wet Tropics Waterways, accessed July 22, 2025

View Source
Preview of Science in Water Quality - Reef & Rainforest Research Centre, accessed August 2, 2025,
Science in Water Quality - Reef & Rainforest Research Centre, accessed August 2, 2025,
Contextual Support

Science in Water Quality - Reef & Rainforest Research Centre, accessed July 22, 2025,

View Source
Preview of Spatiotemporal variability of light attenuation and net ecosystem metabolism in a back-barrier estuary, accessed July 22, 2025
Spatiotemporal variability of light attenuation and net ecosystem metabolism in a back-barrier estuary, accessed July 22, 2025
Contextual Support Journal

Spatiotemporal variability of light attenuation and net ecosystem metabolism in a back-barrier estuary, accessed July 22, 2025

View Source
Preview of Tour TERN's rainforest monitoring SuperSite | TERN Australia, accessed July 22, 2025
Tour TERN's rainforest monitoring SuperSite | TERN Australia, accessed July 22, 2025
Contextual Support Government

Robson Creek Flux Data Release 2022_v2 - TERN Data Discovery Portal

View Source
Preview of Towards environmental management of water turbidity within open coastal waters of the Great Barrier Reef - PubMed, accessed July 22, 2025
Towards environmental management of water turbidity within open coastal waters of the Great Barrier Reef - PubMed, accessed July 22, 2025
Contextual Support Journal

Towards environmental management of water turbidity within open coastal waters of the Great Barrier Reef - PubMed, accessed July 22, 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 Turbidity and light attenuation in coastal waters of the Great Barrier Reef - ResearchOnline@JCU, accessed August 2, 2025,
Turbidity and light attenuation in coastal waters of the Great Barrier Reef - ResearchOnline@JCU, accessed August 2, 2025,
Contextual Support Journal

Australian prawn farming manual Part 4-9.pdf, accessed July 21, 2025,

View Source
Preview of Turbidity and light attenuation in coastal waters of the Great Barrier Reef, accessed July 22, 2025
Turbidity and light attenuation in coastal waters of the Great Barrier Reef, accessed July 22, 2025
Contextual Support GreyLiterature

Turbidity and light attenuation in coastal waters of the Great Barrier Reef, accessed July 22, 2025

View Source
Preview of Underwater Light Characteristics of Turbid Coral Reefs of the Inner Central Great Barrier Reef - Frontiers, accessed July 22, 2025
Underwater Light Characteristics of Turbid Coral Reefs of the Inner Central Great Barrier Reef - Frontiers, accessed July 22, 2025
Contextual Support Journal

Underwater Light Characteristics of Turbid Coral Reefs of the Inner Central Great Barrier Reef - Frontiers, accessed July 22, 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 Guidelines for the Great Barrier Reef Marine Park., accessed August 3, 2025,
Water Quality Guidelines for the Great Barrier Reef Marine Park., accessed August 3, 2025,
Contextual Support Journal

Great Barrier Reef Marine Park Authority (GBRMPA). (2010). Water Quality Guidelines for the Great Barrier Reef Marine Park. Rev. ed. 35

View Source
Preview of Water-quality and ecosystem impacts of recreation in streams: Monitoring and management, accessed July 22, 2025
Water-quality and ecosystem impacts of recreation in streams: Monitoring and management, accessed July 22, 2025
Contextual Support Journal

Using the ANZECC Guidelines and Water Quality Objectives in NSW, accessed July 19, 2025,

View Source
Preview of Waterhouse, J. (2010) Thresholds of major pollutants with regard to ..., accessed July 22, 2025
Waterhouse, J. (2010) Thresholds of major pollutants with regard to ..., accessed July 22, 2025
Contextual Support Journal

Waterhouse, J. (2010) Thresholds of major pollutants with regard to impacts on instream and marine ecosystems, accessed July 21, 2025,

View Source
Preview of wet tropics report card 2024 - waterway environment results, accessed July 18, 2025,
wet tropics report card 2024 - waterway environment results, accessed July 18, 2025,
Contextual Support

wet tropics report card 2024 - waterway environment results, accessed July 18, 2025

View Source

Context

  • Region Australia
  • Biome Tropical & Subtropical Rainforests
  • Land Use Conservation / Protected Natural Areas
  • Assessment Pristine Reference
  • Vegetation Forest
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 1
  • Effective From 15 Mar 2026

Notes

Sustained median turbidity levels above 5 NTU indicate a significantly degraded ecosystem.