Water Turbidity

AUS-TMI-FOR-WTU General Moderate confidence

Benchmark Value

30 NTU

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 11 benchmarks together — the OptimalRange form drives the primary score, while 10 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary UpperThreshold Guard OptimalRange Guard UpperThreshold Guard MaximumOnly Guard OptimalRange Guard OptimalRange Guard MaximumOnly Guard Point Guard OptimalRange Guard MaximumOnly Guard

Evidence & Context

A sustained turbidity level (e.g., lasting for 96 hours or more) of ≥ 30 NTU should be considered the upper boundary for a "high ecological health" state.

Metric Definition:

Water turbidity is a fundamental measure of the optical clarity of water, quantified by the scattering and absorption of light by suspended particulate matter.

Benchmark Definition:

Upper detrimental threshold for a high-health state.

Justification:

Based on documented adverse effects on sensitive macroinvertebrates in comparable Northern Territory tropical ecosystems, where adverse effects were observed after turbidity reached sustained values of 30 NTU.

Supporting Sources (37)

Additional references from the underlying research that informed this benchmark.

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 ...

Preview of Acacia mangium (brown salwood) | CABI Compendium, accessed August 1, 2025,

Acacia mangium (brown salwood) | CABI Compendium, accessed August 1, 2025,

Contextual Support Irrelevant

Acacia mangium (brown salwood) | CABI Compendium, accessed July 30, 2025

Preview of Acacia mangium | ECHOcommunity.org, accessed August 1, 2025,

Acacia mangium | ECHOcommunity.org, accessed August 1, 2025,

Contextual Support GreyLiterature

Acacia mangium | ECHOcommunity.org, accessed August 1, 2025

Preview of An Examination of Stream Water Quality Data from Monitoring of Forest Harvesting in the Eastern Highlands of Victoria - MDPI, accessed August 1, 2025,

An Examination of Stream Water Quality Data from Monitoring of Forest Harvesting in the Eastern Highlands of Victoria - MDPI, accessed August 1, 2025,

Contextual Support Direct Evidence Journal

An Examination of Stream Water Quality Data from Monitoring of Forest Harvesting in the Eastern Highlands of Victoria.

Preview of assessment report 29 - NTEPA - Northern Territory Government, accessed August 1, 2025,

assessment report 29 - NTEPA - Northern Territory Government, accessed August 1, 2025,

Contextual Support Journal

Methods and approaches to support Indigenous water planning: An example from the Tiwi Islands, Northern Territory, Australia - Find an Expert - The University of Melbourne, accessed August 1, 2025

Preview of Australia's State of the Forests Report 2013 - Criterion 4 Conservation and maintenance of soil and water resources, accessed August 1, 2025,

Australia's State of the Forests Report 2013 - Criterion 4 Conservation and maintenance of soil and water resources, accessed August 1, 2025,

Contextual Support

Australia's State of the Forests Report 2013 - Criterion 4 ..., accessed on June 7, 2025,

Preview of Australia's State of the Forests Report 2018 13 Criterion 4 - DAFF, accessed August 1, 2025,

Australia's State of the Forests Report 2018 13 Criterion 4 - DAFF, accessed August 1, 2025,

Contextual Support Journal

Temperate forests and soils [Chapter 6]

Preview of BIODIVERSITY CONSERVATION ON THE TIWI ISLANDS, NORTHERN TERRITORY: Part 3. Management and planning for biodi, accessed August 1, 2025,

BIODIVERSITY CONSERVATION ON THE TIWI ISLANDS, NORTHERN TERRITORY: Part 3. Management and planning for biodi, accessed August 1, 2025,

Contextual Support Journal

Acacia mangium (brown salwood) | CABI Compendium, accessed August 1, 2025

Preview of Criterion 4: Conservation and maintenance of soil and water resources - DAFF, accessed August 1, 2025,

Criterion 4: Conservation and maintenance of soil and water resources - DAFF, accessed August 1, 2025,

Contextual Support

Australia's State of the Forests Report

Preview of Ecological Impact of Planting Indigenous Plants Instead of Exotic Acacia Trees in Anchal - IRJET, accessed August 1, 2025,

Ecological Impact of Planting Indigenous Plants Instead of Exotic Acacia Trees in Anchal - IRJET, accessed August 1, 2025,

Contextual Support Journal

Moisture Distribution in Stems of Acacia mangium, A. auriculiformis and Hybrid Acacia Trees, accessed August 1, 2025

Preview of Effect of Acacia mangium Canopy on Physicochemical Characteristics and Nutrient Concentrations of the Soil at Ayer Hitam Forest Reserve, Malaysia - MDPI, accessed August 1, 2025,

Effect of Acacia mangium Canopy on Physicochemical Characteristics and Nutrient Concentrations of the Soil at Ayer Hitam Forest Reserve, Malaysia - MDPI, accessed August 1, 2025,

Contextual Support

Effect of Acacia mangium Canopy on Physicochemical Characteristics and Nutrient Concentrations of the Soil at Ayer Hitam Forest Reserve, Malaysia - MDPI, accessed August 1, 2025

Preview of Effects of Water Deficiency on Plants of Acacia mangium Willd - ResearchGate, accessed August 1, 2025,

Effects of Water Deficiency on Plants of Acacia mangium Willd - ResearchGate, accessed August 1, 2025,

Contextual Support

Effects of Water Deficiency on Plants of Acacia mangium Willd - ResearchGate, accessed August 1, 2025,

Preview of Forestry | NT.GOV.AU, accessed August 1, 2025,

Forestry | NT.GOV.AU, accessed August 1, 2025,

Contextual Support Irrelevant

Additional Information: Forestry and mining operations on the Tiwi Islands, accessed July 30, 2025

Preview of Guidelines - Water Quality Australia, accessed August 1, 2025,

Guidelines - Water Quality Australia, accessed August 1, 2025,

Contextual Support

Guidelines - Water Quality Australia, accessed August 10, 2025

Preview of guidelines for sustainable forestry on private lands in nsw - ResearchGate, accessed August 1, 2025,

guidelines for sustainable forestry on private lands in nsw - ResearchGate, accessed August 1, 2025,

Contextual Support

guidelines for sustainable forestry on private lands ... - ResearchGate, accessed July 30, 2025

Preview of Inquiry into forestry and mining operations on the Tiwi Islands - Parliament of Australia, accessed August 1, 2025,

Inquiry into forestry and mining operations on the Tiwi Islands - Parliament of Australia, accessed August 1, 2025,

Contextual Support Journal

Tiwi Islands, accessed August 1, 2025

Preview of Invasive Acacia Tree Species Affect Instream Litter Decomposition Through Changes in Water Nitrogen Concentration and Litter Characteristics - PubMed, accessed August 1, 2025,

Invasive Acacia Tree Species Affect Instream Litter Decomposition Through Changes in Water Nitrogen Concentration and Litter Characteristics - PubMed, accessed August 1, 2025,

Contextual Support Journal

Invasive Acacia Tree Species Affect Instream Litter Decomposition Through Changes in Water Nitrogen Concentration and Litter Characteristics - PubMed, accessed August 1, 2025

Preview of Looking to improve water quality? Plant more trees, accessed August 1, 2025,

Looking to improve water quality? Plant more trees, accessed August 1, 2025,

Contextual Support GreyLiterature

Stream nitrate in planted forests - Scion Research, accessed July 31, 2025,

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

Australia's State of the Forests Report 2018 – Criterion 4 - DAFF, accessed August 1, 2025

Preview of Methods and approaches to support Indigenous water planning: An example from the Tiwi Islands, Northern Territory, Australia - Find an Expert - The University of Melbourne, accessed August 1, 2025,

Methods and approaches to support Indigenous water planning: An example from the Tiwi Islands, Northern Territory, Australia - Find an Expert - The University of Melbourne, accessed August 1, 2025,

Contextual Support

Methods and approaches to support Indigenous water planning: An example from the Tiwi Islands, Northern Territory, Australia - Find an Expert - The University of Melbourne, accessed August 1, 2025,

Preview of Moisture Distribution in Stems of Acacia mangium, A. auriculiformis and Hybrid Acacia Trees, accessed August 1, 2025,

Moisture Distribution in Stems of Acacia mangium, A. auriculiformis and Hybrid Acacia Trees, accessed August 1, 2025,

Contextual Support Journal

Effects of Water Deficiency on Plants of Acacia mangium Willd - ResearchGate, accessed August 1, 2025

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

Using the ANZECC Guidelines and Water Quality Objectives in NSW

Preview of Plantation Forestry and Economic Development in the Tiwi Islands - IDEAS/RePEc, accessed August 1, 2025,

Plantation Forestry and Economic Development in the Tiwi Islands - IDEAS/RePEc, accessed August 1, 2025,

Contextual Support GreyLiterature

Inquiry into forestry and mining operations on the Tiwi Islands - Parliament of Australia, accessed August 1, 2025

Preview of Plantations in public drinking water source areas - Government of Western Australia, accessed August 1, 2025,

Plantations in public drinking water source areas - Government of Western Australia, accessed August 1, 2025,

Contextual Support Journal

Plantations in public drinking water source areas - Government of ..., accessed July 31, 2025,

Preview of Private Forestry Guidance Materials, accessed August 1, 2025,

Private Forestry Guidance Materials, accessed August 1, 2025,

Contextual Support Journal

Research and advice from the Grains Research and Development Corporation (GRDC) for the South Australian Mallee region

Preview of Remote sensing in the Kimberley - CSIRO, accessed August 1, 2025,

Remote sensing in the Kimberley - CSIRO, accessed August 1, 2025,

Contextual Support Methodology Source Government

Remote sensing in the Kimberley - CSIRO, accessed August 1, 2025

Preview of Smart water quality monitoring system with cost-effective using IoT - PMC - PubMed Central, accessed August 1, 2025,

Smart water quality monitoring system with cost-effective using IoT - PMC - PubMed Central, accessed August 1, 2025,

Methodology Source Journal

Smart water quality monitoring system with cost-effective using IoT - PMC - PubMed Central, accessed August 1, 2025,

Preview of Tiwi Islands port project needs no environmental risk assessment 13 EPA - The Guardian, accessed August 1, 2025,

Tiwi Islands port project needs no environmental risk assessment 13 EPA - The Guardian, accessed August 1, 2025,

Contextual Support

Tiwi Islands port project needs no environmental risk assessment 13 EPA - The Guardian, accessed August 1, 2025,

Preview of TIWI ISLANDS REGIONAL NATURAL RESOURCE MANAGEMENT STRATEGY, accessed August 1, 2025,

TIWI ISLANDS REGIONAL NATURAL RESOURCE MANAGEMENT STRATEGY, accessed August 1, 2025,

Contextual Support Journal

Tiwi Islands water study - Territory Stories, accessed August 1, 2025

Preview of Tiwi Islands water study - Territory Stories, accessed August 1, 2025,

Tiwi Islands water study - Territory Stories, accessed August 1, 2025,

Contextual Support Government

Tiwi Islands port project needs no environmental risk assessment – EPA - The Guardian, accessed August 1, 2025

Preview of Tiwi Islands, accessed August 1, 2025,

Tiwi Islands, accessed August 1, 2025,

Contextual Support Journal

BIODIVERSITY CONSERVATION ON THE TIWI ISLANDS, NORTHERN TERRITORY: Part 3. Management and planning for biodi, accessed August 1, 2025

Preview of Turbidity in Surface Water 14 Rehabilitation Standard for the Ranger uranium mine - DCCEEW, accessed August 1, 2025,

Turbidity in Surface Water 14 Rehabilitation Standard for the Ranger uranium mine - DCCEEW, accessed August 1, 2025,

Direct Evidence Government

ANZG (2018) Australian and New Zealand Guidelines for Fresh and Marine Water Quality

Preview of Water - Transparency Portal, accessed August 1, 2025,

Water - Transparency Portal, accessed August 1, 2025,

Contextual Support Government

TIWI ISLANDS REGIONAL NATURAL RESOURCE MANAGEMENT STRATEGY, accessed August 1, 2025

Preview of Water quality for farm water supplies | Managing dams - Agriculture Victoria, accessed August 1, 2025,

Water quality for farm water supplies | Managing dams - Agriculture Victoria, accessed August 1, 2025,

Contextual Support Government

Regenerative Agriculture and Livestock Integration on Australian Cattle Farms

Preview of Water quality guidelines - Queensland Environment Department, accessed August 1, 2025,

Water quality guidelines - Queensland Environment Department, accessed August 1, 2025,

Contextual Support Direct Evidence Government

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

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 ...

Preview of Water-quality and ecosystem impacts of recreation in streams: Monitoring and management, accessed August 1, 2025,

Water-quality and ecosystem impacts of recreation in streams: Monitoring and management, accessed August 1, 2025,

Contextual Support Direct Evidence Journal

Water-quality and ecosystem impacts of recreation in streams: Monitoring and management, accessed July 18, 2025,

Context

Region Australia
Biome Tropical & Subtropical Maritime Islands
Land Use Production Forestry
Assessment Not Stated
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 28 May 2026

Notes

Upper Detrimental Threshold: 30 NTU. Sustained level is defined as lasting for 96 hours or more. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TMI-FOR-WTU family.