Water Nitrate
Benchmark Value
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
Evidence & Context
Proposed Benchmark Value: 0.014 mg/L (as Oxidised Nitrogen, NOx, effectively representing Nitrate).
Water nitrate concentration, measured as Oxidised Nitrogen (NOx)—the sum of nitrate and nitrite.
The lowest reliably measurable concentration found in the least-disturbed, real-world analogue catchments.
The reference value of 0.014 mg/L is the median Oxidised Nitrogen (NOx, effectively nitrate) concentration from "Very Good" condition streams in the South Australian Mount Lofty Ranges, a region containing temperate woodlands. This value is selected as it represents the best available real-world measurement of a high-health, "least disturbed" system and aligns with the ecological principle that intact Temperate Grassy Woodlands are low-nutrient environments with tight nitrogen cycling and minimal nutrient leakage into waterways.
Sources (1)
Australian and New Zealand Guidelines for Fresh and Marine Water Quality (2000)
View SourceSupporting Sources (24)
Additional references from the underlying research that informed this benchmark.
2022 Recommended Land Management for the Water Quality Protection Lands Austin, Texas - AustinTexas.gov
View Source
Manning, A. D., Cunningham, R. B., Tongway, D., & Lindenmayer, D. B. (2020). Woodlands and woody debris: Understanding structure and composition to inform restoration. PLoS ONE, 15(3), e0224258.
View SourceANZECC & ARMCANZ (2000) guidelines - Water Quality Australia
View Source
Northern Territory Government (2020) Darwin Harbour Region Water Quality Objectives, Report Card Section 3.0.
View Source
Turbidity | Australia state of the environment 2021
View SourceANZECC (2000) Australian and New Zealand Guidelines for Fresh and Marine Water Quality.
View SourceWater Quality Guidelines Home - Water Quality Australia
View SourceCharacterising the relationship between water quality and water quantity, accessed August 12, 2025
View Source
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 SourceAustralian and New Zealand guidelines for fresh and marine water quality, accessed August 3, 2025
View Source
Using the ANZECC Guidelines and Water Quality Objectives in NSW
View SourceThe phosphorus and nitrogen requirements of temperate pasture species and their influence on grassland botanical composition - The Australian National University
View SourceAustralian and New Zealand Guidelines for Fresh and Marine Water Quality (ANZG 2018)
View SourceAustralian and New Zealand Guidelines for Fresh and Marine Water Quality (ANZG)
View SourceNitrate in freshwater, toxicant default guideline values for protecting aquatic ecosystems, technical brief
View SourceNitrate toxicity guidelines for the National Objectives Framework - NIWA
View SourceReal-time water quality monitoring | Estuaries - Environment and Heritage, accessed August 12, 2025
View Source
The impact of nitrate pollution in waterways on freshwater species, accessed July 24, 2025,
View SourceTotal Nitrogen - DCCEEW
View Source
Nitrate in freshwater, toxicant default guideline values for protecting aquatic ecosystems
View Source
What's wrong with the Australian River Assessment System (AUSRIVAS)?, accessed August 3, 2025
View SourceDrivers of water quality in Afromontane-savanna rivers - Frontiers
View SourceWater Quality Objectives - Border Rivers - NSW Government, accessed August 12, 2025
View Source(PDF) Impact of mitigated forestry activities on turbidity: assessing ...
View Source