Water Turbidity
Benchmark Value
Scoring Curve
This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context.
Evidence & Context
Proposed Potential Upper Detrimental Threshold: > 10 NTU (as an 80th percentile)
Water turbidity (80th percentile)
This benchmark indicates the upper detrimental threshold for water turbidity (80th percentile) in alpine and subalpine streams under livestock grazing, beyond which significant ecological impairment occurs.
Values persistently exceeding 10 NTU are indicative of significant ecological impairment, approaching values seen in moderately to heavily disturbed systems.
Sources (1)
Feral horses (Equus caballus) increase suspended sediment in subalpine streams
View SourceSupporting Sources (14)
Additional references from the underlying research that informed this benchmark.
An Examination of Stream Water Quality Data from Monitoring of Forest Harvesting in the Eastern Highlands of Victoria.
View SourceAssessing water quality - ACT Waterwatch.
View SourceAustralian Alps Liaison Committee (AALC). (2011). Caring for our Australian Alps catchments: A climate change action strategy. Department of Climate Change and Energy Efficiency.
View SourceBritish Columbia Ministry of Environment. (2001). Summary of water quality guidelines for turbidity, suspended and benthic sediments.
View SourceDetermining Tipping Points and Responses of Macroinvertebrate Traits to Abiotic Factors in Support of River Management
View SourceScanes, P., & Whitehead, A. (2019). Trigger values for New Zealand rivers: A comparison with south-eastern Australia. Ministry for the Environment, New Zealand.
View SourceDepartment of Climate Change, Energy, the Environment and Water. (2006). Lowland Native Grasslands of Tasmania Listing Advice.
View SourceConservation land management aims to preserve ecological integrity and control erosion.9
View SourceCaring for our Australian Alps Catchments, accessed on May 28, 2025
View SourceTurbidity | Australian Drinking Water Guidelines - NHMRC, accessed August 3, 2025
View SourceANZG (2018) Australian and New Zealand Guidelines for Fresh and Marine Water Quality
View SourceVictorian Water Quality Analysis 2022 Technical Report
View SourceNational Guidelines for Water Quality | Department of Natural ...
View SourceThe Australian Alps Bioregion - Environment and Heritage, accessed on May 27, 2025,
View Source