Water Nitrate

AUS-TDG-AGR-WNI General Moderate confidence

Benchmark Value

0.2 mg/L

Thresholds: Lower: —, Upper: 0.2

Direction: Lower is desirable ↓

Form: UpperThreshold

Scoring Curve

This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context.

Evidence & Context

For maintaining "high environmental health" and preventing eutrophication, sustained concentrations exceeding 0.2 – 0.5 mg/L NO3− are considered detrimental, indicating a departure from the best available condition.

Metric Definition:

Lower bound of upper detrimental threshold range for nitrate concentration indicating onset of eutrophication risk.

Benchmark Definition:

Threshold nitrate concentration above which eutrophication risk increases, indicating ecological degradation.

Justification:

Based on ANZECC (2000) regional nutrient guidelines and general eutrophication science.

Sources (1)

Preview of Turbidity in Surface Water 14 Rehabilitation Standard for the Ranger uranium mine - DCCEEW, accessed August 1, 2025,

Turbidity in Surface Water 14 Rehabilitation Standard for the Ranger uranium mine - DCCEEW, accessed August 1, 2025, Government

ANZG (2018) Australian and New Zealand Guidelines for Fresh and Marine Water Quality

View Source

Supporting Sources (3)

Additional references from the underlying research that informed this benchmark.

Memorandum - Nitrate guideline values in ANZECC 2000, accessed August 8, 2025

Contextual Support Journal

Hickey, C. (2002). Nitrate guideline values in ANZECC 2000. Memorandum MFE02237 prepared for Ministry for the Environment (New Zealand). NIWA Client Report: HAM2002-126.

View Source

tuvalu-data.sprep.org, accessed May 11, 2025,

Contextual Support Journal

Palaeovalley Groundwater Resources in Arid and Semi-Arid Australia - Geoscience Australia, accessed July 31, 2025,

View Source

webcat.niwa.co.nz, accessed May 11, 2025,

Contextual Support

webcat.niwa.co.nz, accessed May 11, 2025

View Source

Context

Region Australia
Biome Temperate Dry Woodlands & Native Grasslands
Land Use Agricultural Crop Production
Assessment Conservation Target
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 31 May 2026

Notes

This threshold marks the departure from high environmental health and best available condition in agricultural waters. Upper Critical Threshold: 0.5 mg/L.

Related Benchmarks

Other benchmarks in the AUS-TDG-AGR-WNI family.