Water Turbidity

AUS-AKW-IND-WTU General Low confidence

Benchmark Value

20 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 9 benchmarks together — the OptimalRange form drives the primary score, while 8 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary MaximumOnly Guard MaximumOnly Guard MaximumOnly Guard MaximumOnly Guard MinimumOnly Guard MinimumOnly Guard MaximumOnly Guard OptimalRange Guard

Evidence & Context

Based on analogous systems, a trigger value of < 20 NTU for persistent, non-flowing pools is proposed to signal potential containment failure.

Metric Definition:

Water turbidity in off-site surface waters under persistent, non-flowing conditions

Benchmark Definition:

This benchmark represents a maximum turbidity level in pooled, non-flowing surface waters in the biome under industrial land use, indicating potential containment failure if exceeded.

Justification:

This value is inferred for the pooled, non-flow condition of ephemeral surface waters adjacent to a best-practice industrial site. It is based on the principle that best practice is zero discharge, meaning off-site water quality should reflect a minimally disturbed state.

Sources (2)

Preview of A review of water quality studies relevant to northern Australia - CSIRO, accessed July 21, 2025,

A review of water quality studies relevant to northern Australia - CSIRO, accessed July 21, 2025, Journal

Salinity and water quality

View Source

Preview of Australia's inland waters - Water Quality Australia

Australia's inland waters - Water Quality Australia Government

Australia's inland waters - Water Quality Australia, accessed July 26, 2025

View Source

Context

Region Australia
Biome Arid Karstic Woodlands & Shrublands
Land Use Industrial & Infrastructure Use
Assessment Not Stated
Evidence Type ReferenceCondition

Lifecycle

Status Superseded
Version 1
Effective From 4 Jun 2026
Effective To 4 Jun 2026

Notes

This value is a trigger to investigate containment failure, not a discharge limit. It reflects natural background conditions and is derived from qualitative descriptions of 'Good' condition arid streams and default trigger values for lowland rivers in other regions. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-AKW-IND-WTU family.