Water Nitrate — Benchmark Detail

Benchmark Value

0.01 mg/L

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 7 benchmarks together — the OptimalRange form drives the primary score, while 6 guard(s) constrain the result.

Contributing Benchmarks

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

Evidence & Context

The selected benchmark is: Reference Value: ²60.010 (median of annual values from multiple reference sites)

Metric Definition:

Water nitrate concentration measured as NOx-N in mg per liter.

Benchmark Definition:

This benchmark represents the best available natural condition for water nitrate concentration in Australian alpine and subalpine protected areas, based on median values from multiple reference sites.

Justification:

This value is derived from consistently low median concentrations observed at multiple upstream control and reference sites within Kosciuszko National Park, representing high ecological health in minimally disturbed alpine catchments.

Sources (3)

Preview of Australian and New Zealand Guidelines for Fresh and Marine Water ..., accessed August 5, 2025,

Australian and New Zealand Guidelines for Fresh and Marine Water ..., accessed August 5, 2025, Journal

tuvalu-data.sprep.org

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Preview of Characterising alpine peatland water quality on the Bogong High Plains, Victoria - Threatened Species Recovery Hub

Characterising alpine peatland water quality on the Bogong High Plains, Victoria - Threatened Species Recovery Hub Journal

Toxicant default guideline values for aquatic ecosystem protection ...

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NSW alpine resorts environmental performance report 2020–21 Journal

NSW Alpine Resorts Environmental Performance Report 2020–21

View Source

Supporting Sources (2)

Additional references from the underlying research that informed this benchmark.

Catchment Health Indicator Program Report 2021 - Upper Murrumbidgee Waterwatch, accessed August 12, 2025,

Regulatory Framework Journal

ANZECC/ARMCANZ (2000) Guidelines

View Source

Toxicant default guideline values for aquatic ecosystem protection ..., accessed August 8, 2025

Regulatory Framework Journal

Nitrate in freshwater, toxicant default guideline values for protecting aquatic ecosystems

View Source

Context

Region Australia
Biome Alpine and Subalpine Complex
Land Use Conservation / Protected Natural Areas
Assessment Pristine Reference
Evidence Type ReferenceCondition

Lifecycle

Status Active
Version 1
Effective From 3 Jun 2026

Notes

No upper detrimental threshold — higher values are always better up to natural saturation. The benchmark of ²60.010 mg NOx-N/L is consistent with observations from Victorian alpine peatland headwaters and is more stringent than the ANZECC (2000) default trigger value for South-East Australian upland rivers (0.015 mg N/L).

Related Benchmarks

Other benchmarks in the AUS-ASC-CON-WNI family.