Water Turbidity

AUS-AMR-AQU-WTU General High confidence

Benchmark Value

25 NTU

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 15 benchmarks together — the OptimalRange form drives the primary score, while 14 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary MaximumOnly Guard OptimalRange Guard Point Guard MaximumOnly Guard MaximumOnly Guard MaximumOnly Guard MaximumOnly Guard OptimalRange Guard MaximumOnly Guard Point Guard LowerThreshold Guard OptimalRange Guard MaximumOnly Guard MaximumOnly Guard

Evidence & Context

A turbidity measurement exceeding > 25 NTU indicates that the system is no longer functioning as designed and requires immediate corrective action to prevent catastrophic stock losses.

Metric Definition:

Upper detrimental threshold of water turbidity indicating system malfunction and degraded state.

Benchmark Definition:

Upper detrimental turbidity threshold indicating system malfunction and degraded state in arid mountain aquaculture.

Justification:

Exceeding 25 NTU signals filter failure, overfeeding, or algal bloom leading to negative impacts.

Sources (1)

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

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

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

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Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

Best Pratice Environmental Management Guidelines for ... - VFA, accessed July 20, 2025,

Direct Evidence Government

Best Pratice Environmental Management Guidelines for ... - VFA

View Source

Preview of Effects of turbidity, temperature and predation cue on the stress response of juvenile delta smelt | Conservation Physiology | Oxford Academic

Effects of turbidity, temperature and predation cue on the stress response of juvenile delta smelt | Conservation Physiology | Oxford Academic

Contextual Support Journal

Effects of turbidity, temperature and predation cue on the stress response of juvenile delta smelt | Conservation Physiology | Oxford Academic

View Source

Water quality for primary industries, accessed July 30, 2025,

Direct Evidence Government

Low turbidity in recirculating aquaculture systems (RAS) reduces feeding behavior and increases stress-related physiological parameters in pikeperch (Sander lucioperca) during grow-out

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Context

Region Australia
Biome Arid Mountain Ranges & Uplands
Land Use Aquaculture
Assessment Not Stated
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 4 Jun 2026

Notes

An upper detrimental threshold of > 25 NTU indicates system failure and a degraded state. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-AMR-AQU-WTU family.