Water Nitrate

AUS-TMS-LVG-WNI General Moderate confidence

Benchmark Value

0.019 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 10 benchmarks together — the OptimalRange form drives the primary score, while 9 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

The median concentration of Oxidised Nitrogen (NOx-N) from pristine northern Australian systems, reported as 0.019 mg/L N, stands out as a strong candidate for the reference value.

Metric Definition:

Oxidised Nitrogen (NOx-N) concentration in water, predominantly nitrate and nitrite nitrogen.

Benchmark Definition:

This benchmark represents the typical concentration of oxidised nitrogen in water from pristine northern Australian tropical savanna systems, indicating near-natural water quality under minimal nutrient export.

Justification:

This value reflects the naturally oligotrophic state of these environments and assumes that best-practice grazing minimizes nutrient export to achieve near-pristine water quality. It is supported by data from multiple pristine catchments and regional water quality objectives.

Sources (1)

Preview of www.rrrc.org.au, accessed May 15, 2025,
www.rrrc.org.au, accessed May 15, 2025, Journal

Sediments and nutrients in north Queensland tropical streams: changes with agricultural development and pristine condition status (Technical Report No. 62, Australian Rainforest CRC, 2006)

View Source

Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

Preview of environment.nt.gov.au, accessed May 11, 2025,
environment.nt.gov.au, accessed May 11, 2025,
Direct Evidence Journal

Water Quality objectives for the region - Department of Lands, Planning and Environment

View Source
Preview of The impact of nitrate pollution in waterways on freshwater species, accessed August 8, 2025
The impact of nitrate pollution in waterways on freshwater species, accessed August 8, 2025
Direct Evidence Journal

Toxicant default guideline values for aquatic ecosystem protection ...

View Source
Preview of Water Quality objectives for the region - Department of Lands, Planning and Environment
Water Quality objectives for the region - Department of Lands, Planning and Environment
Direct Evidence Journal

Water Quality objectives for the region - Department of Lands, Planning and Environment

View Source

Context

  • Region Australia
  • Biome Tropical Monsoonal Savannas
  • Land Use Livestock Grazing & Pasture
  • Assessment Pristine Reference
  • Evidence Type ReferenceCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 25 Mar 2026

Notes

The median is preferred over the mean because it is less influenced by occasional high readings or outliers. NOx-N serves as a close approximation of Nitrate-N in these contexts.

Related Benchmarks

Other benchmarks in the AUS-TMS-LVG-WNI family.

11.3 mg/L Moderate
Livestock Grazing & Pasture · Pristine Reference
MaximumOnly Active v3
— mg/L Moderate
Livestock Grazing & Pasture · Pristine Reference
OptimalRange Active v1
— mg/L Moderate
Livestock Grazing & Pasture · Conservation Target
OptimalRange Active v1
2.4 mg/L Moderate
Livestock Grazing & Pasture · Pristine Reference
MaximumOnly Superseded v2
0.05 mg/L Moderate
Livestock Grazing & Pasture · Pristine Reference
MaximumOnly Superseded v1