Water Nitrate

AUS-TSR-URB-WNI General Moderate confidence

Benchmark Value

0.015 mg/L

Direction: Lower is desirable ↓

Form: Point

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 13 benchmarks together — the OptimalRange form drives the primary score, while 12 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

The WQO for Oxidised Nitrogen (NOx ) in the lowland fresh waters of the Black River Basin is 0.015 mg/L (as N).

Metric Definition:

Concentration of Oxidised Nitrogen (NOx), the sum of nitrate (NO3²2) and nitrite (NO2²2), in lowland fresh waters representing the 80th percentile of least-disturbed reference streams.

Benchmark Definition:

This benchmark represents the water quality objective for oxidised nitrogen in lowland freshwaters of the Black River Basin, reflecting the 80th percentile of least-disturbed reference streams in a managed tropical landscape.

Justification:

Derived using the ANZG referential method, based on the 80th percentile of data from the least-disturbed reference sites in the region. It represents a high level of ecological health.

Sources (1)

Townsville basins - Queensland Environment Department, accessed August 2, 2025,

Environmental Protection (Water and Wetland Biodiversity) Policy 2019 - Schedule 1 (referencing WQOs for Black River Basin)

View Source

Supporting Sources (2)

Additional references from the underlying research that informed this benchmark.

Black ross (townsville) - water Quality improvement plan

Contextual Support Journal

Black ross (townsville) - water Quality improvement plan

View Source

Preview of Land-use effects on water quality in an intensively managed catchment in the Australian humid tropics | Request PDF - ResearchGate, accessed July 30, 2025,

Land-use effects on water quality in an intensively managed catchment in the Australian humid tropics | Request PDF - ResearchGate, accessed July 30, 2025,

Contextual Support Journal

Land-use effects on water quality in an intensively managed ...

View Source

Context

Region Australia
Biome Tropical & Subtropical Rainforests
Land Use Urban & Developed Use
Assessment Not Stated
Evidence Type ReferenceCondition

Lifecycle

Status Superseded
Version 1
Effective From 3 Jun 2026
Effective To 3 Jun 2026

Notes

No upper detrimental threshold ²15 higher values are always worse for ecological health in this context. This benchmark is the Queensland Government's official Water Quality Objective for Oxidised Nitrogen (NOx) in lowland freshwaters of the Black River Basin, a representative tropical catchment. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TSR-URB-WNI family.