Water Turbidity

AUS-TMI-URB-WTU General Moderate confidence

Benchmark Value

5 NTU
Range: — to 5 NTU
Thresholds: Lower: —, Upper: 5
Optimal Range: — to 5
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.

Evidence & Context

The optimal range for water turbidity in this context is < 5 NTU.

Metric Definition:

Optimal turbidity level below which coral reef and seagrass ecosystems thrive.

Benchmark Definition:

Optimal turbidity threshold for ecosystem health.

Justification:

Supported by Wet Tropics Report Card, Loya (1976) coral reef health study, and Lord Howe Island wastewater standards.

Sources (3)

Preview of Chlorophyll a and turbidity patterns over coral reefs systems of La ..., accessed August 2, 2025,
Chlorophyll a and turbidity patterns over coral reefs systems of La ..., accessed August 2, 2025, Journal

Chlorophyll a and turbidity patterns over coral reefs systems of La ..., accessed August 2, 2025,

View Source
Preview of Lord Howe Island On-Site Wastewater Management Strategy, accessed August 3, 2025,
Lord Howe Island On-Site Wastewater Management Strategy, accessed August 3, 2025, Journal

Lord Howe Island On-Site Wastewater Management Strategy, accessed August 2, 2025,

View Source
Preview of wet tropics report card 2024 - waterway environment results, accessed August 2, 2025,
wet tropics report card 2024 - waterway environment results, accessed August 2, 2025, GreyLiterature

Report Card - Wet Tropics Waterways, accessed August 2, 2025,

View Source

Supporting Sources (34)

Additional references from the underlying research that informed this benchmark.

Preview of 7.4 Patterns of Primary Production – Introduction to Oceanography, accessed August 2, 2025,
7.4 Patterns of Primary Production – Introduction to Oceanography, accessed August 2, 2025,
Contextual Support GreyLiterature

7.4 Patterns of Primary Production – Introduction to Oceanography, accessed August 2, 2025,

View Source
Preview of Australia's bioregions (IBRA) - DCCEEW, accessed July 15, 2025
Australia's bioregions (IBRA) - DCCEEW, accessed July 15, 2025
Contextual Support

Interim Biogeographic Regionalisation for Australia (IBRA), Version 7 (Regions), accessed July 12, 2025,

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 Declining water quality - Great Barrier Reef Marine Park Authority, accessed August 1, 2025
Declining water quality - Great Barrier Reef Marine Park Authority, accessed August 1, 2025
Contextual Support Government

Denitrification in intertidal sediments of a tropical estuary subject to increasing development pressures - Northern Territory Government

View Source
Preview of Diving deeper into nutrient pathways to help protect Lord Howe Island's marine haven, accessed August 4, 2025,
Diving deeper into nutrient pathways to help protect Lord Howe Island's marine haven, accessed August 4, 2025,
Contextual Support GreyLiterature

Australian Institute of Marine Science (AIMS). (2024, September 4). Diving deeper into nutrient pathways to help protect Lord Howe Island's marine haven. 9

View Source
Preview of Evaluating the water quality of stormwater runoffs in urban area - ResearchGate, accessed August 2, 2025,
Evaluating the water quality of stormwater runoffs in urban area - ResearchGate, accessed August 2, 2025,
Contextual Support GreyLiterature

Evaluating the water quality of stormwater runoffs in urban area - ResearchGate, accessed August 2, 2025,

View Source
Preview of FAQ Report Card | Healthy Rivers to Reef Partnership, accessed August 2, 2025,
FAQ Report Card | Healthy Rivers to Reef Partnership, accessed August 2, 2025,
Contextual Support GreyLiterature

FAQ Report Card | Healthy Rivers to Reef Partnership, accessed August 2, 2025,

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 Improving water quality - DCCEEW, accessed August 2, 2025,
Improving water quality - DCCEEW, accessed August 2, 2025,
Contextual Support Government

Improving water quality - DCCEEW, accessed August 2, 2025,

View Source
Preview of Incredible Great Barrier Reef Islands For Your Holiday - Visitor's Guide - Queensland, accessed July 30, 2025,
Incredible Great Barrier Reef Islands For Your Holiday - Visitor's Guide - Queensland, accessed July 30, 2025,
Contextual Support

Incredible Great Barrier Reef Islands For Your Holiday - Visitor's Guide - Queensland, accessed August 2, 2025,

View Source
Preview of Large-scale effects of turbidity on coral bleaching in the Hawaiian islands - Frontiers, accessed August 2, 2025,
Large-scale effects of turbidity on coral bleaching in the Hawaiian islands - Frontiers, accessed August 2, 2025,
Contextual Support Journal

Large-scale effects of turbidity on coral bleaching in the Hawaiian islands - Frontiers, accessed August 2, 2025,

View Source
Preview of Largest study of water quality effects on Great Barrier Reef | AIMS, accessed August 2, 2025,
Largest study of water quality effects on Great Barrier Reef | AIMS, accessed August 2, 2025,
Contextual Support Government

Largest study of water quality effects on Great Barrier Reef | AIMS, accessed August 2, 2025,

View Source
Preview of Long-term spatial variations in turbidity and temperature provide new insights into coral-algal states on extreme/marginal reefs - ResearchOnline@JCU, accessed August 2, 2025,
Long-term spatial variations in turbidity and temperature provide new insights into coral-algal states on extreme/marginal reefs - ResearchOnline@JCU, accessed August 2, 2025,
Contextual Support Journal

Long-term spatial variations in turbidity and temperature provide new insights into coral-algal states on extreme/marginal reefs - ResearchOnline@JCU

View Source
Preview of Lord Howe Island Biodiversity Management Plan - DCCEEW, accessed August 4, 2025,
Lord Howe Island Biodiversity Management Plan - DCCEEW, accessed August 4, 2025,
Contextual Support Journal

Maintain and improve groundcover - Local Land Services, accessed August 3, 2025

View Source
Preview of Lord Howe Island Marine Park - Wikipedia, accessed August 3, 2025,
Lord Howe Island Marine Park - Wikipedia, accessed August 3, 2025,
Contextual Support GreyLiterature

Lord Howe Island Marine Park - Wikipedia, accessed August 2, 2025,

View Source
Preview of Lord Howe Island Marine Park News Water Quality Research Collaboration, accessed August 3, 2025,
Lord Howe Island Marine Park News Water Quality Research Collaboration, accessed August 3, 2025,
Contextual Support Journal

Lord Howe Island Marine Park. (2024, June). Lord Howe Island Marine Park News. 8

View Source
Preview of Managing urban and non-agricultural run-off to the Reef ..., accessed August 2, 2025,
Managing urban and non-agricultural run-off to the Reef ..., accessed August 2, 2025,
Contextual Support Government

Managing urban and non-agricultural run-off to the Reef ..., accessed August 2, 2025,

View Source
Preview of Phytoplankton primary production in the world's estuarine-coastal ecosystems - BG, accessed August 2, 2025,
Phytoplankton primary production in the world's estuarine-coastal ecosystems - BG, accessed August 2, 2025,
Contextual Support Journal

Phytoplankton primary production in the world's estuarine-coastal ecosystems - BG, accessed August 2, 2025,

View Source
Preview of Protecting our Great Barrier Reef - Department of the Environment, Tourism, Science and Innovation (DETSI), Queensland, accessed August 3, 2025,
Protecting our Great Barrier Reef - Department of the Environment, Tourism, Science and Innovation (DETSI), Queensland, accessed August 3, 2025,
Contextual Support Government

Protecting our Great Barrier Reef - Department of the Environment, Tourism, Science and Innovation (DETSI), Queensland, accessed August 2, 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 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 Responses of coral reefs and reef organisms to sedimentation, accessed August 2, 2025,
Responses of coral reefs and reef organisms to sedimentation, accessed August 2, 2025,
Contextual Support

Responses of coral reefs and reef organisms to sedimentation, accessed August 2, 2025,

View Source
Preview of Sediments and turbidity – Caribbean Coral Reef Institute (CCRI), accessed August 2, 2025,
Sediments and turbidity – Caribbean Coral Reef Institute (CCRI), accessed August 2, 2025,
Contextual Support

Sediments and turbidity – Caribbean Coral Reef Institute (CCRI), accessed August 2, 2025,

View Source
Preview of The most beautiful Australian islands - Tourism Australia, accessed August 2, 2025,
The most beautiful Australian islands - Tourism Australia, accessed August 2, 2025,
Contextual Support Irrelevant

Lord Howe Island Subtropical Forests | One Earth

View Source
Preview of Turbid Coral Reefs: Past, Present and Future—A Review - MDPI, accessed August 2, 2025,
Turbid Coral Reefs: Past, Present and Future—A Review - MDPI, accessed August 2, 2025,
Contextual Support Journal

Turbid Coral Reefs: Past, Present and Future—A Review - MDPI, accessed August 2, 2025,

View Source
Preview of Turbid reefs moderate coral bleaching under climate‐related temperature stress - PMC, accessed August 2, 2025,
Turbid reefs moderate coral bleaching under climate‐related temperature stress - PMC, accessed August 2, 2025,
Contextual Support Journal

Turbid reefs moderate coral bleaching under climate‐related temperature stress - PMC, accessed August 2, 2025,

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 Direct Evidence Journal

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

View Source
Preview of Urban stormwater quality - Queensland Environment Department, accessed August 2, 2025,
Urban stormwater quality - Queensland Environment Department, accessed August 2, 2025,
Contextual Support Regulatory Framework Government

Urban stormwater quality - Queensland Environment Department, accessed August 1, 2025,

View Source
Preview of Water quality | State of the Environment Report 2020, accessed August 2, 2025,
Water quality | State of the Environment Report 2020, accessed August 2, 2025,
Contextual Support

Water quality | State of the Environment Report 2020, accessed August 2, 2025,

View Source
Preview of Water Quality and Monitoring - Indian River Lagoon, accessed August 2, 2025,
Water Quality and Monitoring - Indian River Lagoon, accessed August 2, 2025,
Contextual Support GreyLiterature

Water Quality and Monitoring - Indian River Lagoon, accessed August 2, 2025,

View Source
Preview of Water quality as a regional driver of coral biodiversity and macroalgae on the Great Barrier Reef - PubMed, accessed August 2, 2025,
Water quality as a regional driver of coral biodiversity and macroalgae on the Great Barrier Reef - PubMed, accessed August 2, 2025,
Contextual Support Journal

Water quality as a regional driver of coral biodiversity and macroalgae on the Great Barrier Reef - PubMed, accessed August 2, 2025,

View Source
Preview of Water quality guidelines for the Great Barrier Reef - eAtlas, accessed August 2, 2025,
Water quality guidelines for the Great Barrier Reef - eAtlas, accessed August 2, 2025,
Contextual Support

Water quality guidelines for the Great Barrier Reef - eAtlas, accessed August 2, 2025,

View Source
Preview of Water Quality Improvement - Townsville City Council, accessed August 2, 2025,
Water Quality Improvement - Townsville City Council, accessed August 2, 2025,
Contextual Support Irrelevant

Water Quality Improvement - Townsville City Council, accessed August 2, 2025,

View Source
Preview of Water quality of surface water environments - NSW Government Water, accessed August 1, 2025,
Water quality of surface water environments - NSW Government Water, accessed August 1, 2025,
Contextual Support Government

National Guidelines for Water Quality | Department of Natural ...

View Source

Context

  • Region Australia
  • Biome Tropical & Subtropical Maritime Islands
  • Land Use Urban & Developed Use
  • Assessment Pristine Reference
  • Evidence Type HealthyOperationalRange

Lifecycle

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

Notes

Values below 5 NTU align with 'Very Good' to 'Good' ecological grades and are technologically achievable.