Historic General Quality Assessment (GQA) Headline Indicators of Water Courses - Nutrients
The General Quality Assessment (GQA) Headline Indicator scheme or GQAHI (previously known as GQA) was the national indicator for water quality in rivers and canals. It was designed to provide an accurate and consistent assessment of the state of water quality and how it changes over time. These assessments were made for Biological, Chemical and Nutrients and undertaken for discrete river stretches. This datasets relates to the nutrient assessments. In Wales we maintained the full GQA network until 2010 based on 800 sampling sites which provided information for approximately 4700km. The GQAHI/GQA scheme was designed to provide an accurate and consistent assessment of the state of water quality and how it changes over time. The Nutrients GQA described quality in terms of two nutrients: nitrates (mg NO3 /l) and phosphates (mg P/l) and graded from 1 to 6.
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Dull adnabod
- Dynodydd
- NRW_DS116326
- Teitl Amgen
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- AfA163 Historic GQA Headline Indicators of Water Courses – Nutrients
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- English
- Datganiad
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The Nutrients GQA described quality in terms of two nutrients: nitrates (mg NO3 /l) and phosphates (mg P/l) and graded from 1 to 6. Grades were allocated for both phosphate and nitrate; they were not combined into a single nutrients grade. There were no set 'good' or 'bad' concentrations for nutrients in rivers in the way that we describe chemical and biological quality. Rivers in different parts of the country have naturally different concentrations of nutrients. ‘Very low’ nutrient concentrations, for example, are not necessarily good or bad; the classifications merely stated that concentrations in this river were very low relative to other rivers. Classification for phosphate Grade limit (mgP/l) Average Description: 0.02 to 0.06 Low >0.06 to 0.1 Moderate >0.1 to 0.2 High >0.2 to 1.0 Very high >1.0 Excessively high Classification for nitrate Grade limit (mg NO3/l) Average Description: 5 to 10 Low >10 to 20 Moderately low >20 to30 Moderate >30 to 40 High >40 Very high. 2009 was the final year of the scheme.
- Dyddiad cyfeirnod y set ddata (Cyhoeddiad)
- 2016-07-01
Ystod amser
- Dyddiad cychwyn
- 2000-01-01
- Dyddiad gorffen
- 2009-12-31
- Categori pwnc
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- Inland waters
Rhychwant
Rhychwant
- Hyd
- Wales (WLS)
Dosbarthiad
Dosbarthiad
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Excel
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Documents
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Ansawdd
Ansawdd Data
- Cwmpas Ansawdd
- Dataset
- Datganiad
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The Nutrients GQA described quality in terms of two nutrients: nitrates (mg NO3 /l) and phosphates (mg P/l) and graded from 1 to 6. Grades were allocated for both phosphate and nitrate; they were not combined into a single nutrients grade. There were no set 'good' or 'bad' concentrations for nutrients in rivers in the way that we describe chemical and biological quality. Rivers in different parts of the country have naturally different concentrations of nutrients. ‘Very low’ nutrient concentrations, for example, are not necessarily good or bad; the classifications merely stated that concentrations in this river were very low relative to other rivers. Classification for phosphate Grade limit (mgP/l) Average Description: 0.02 to 0.06 Low >0.06 to 0.1 Moderate >0.1 to 0.2 High >0.2 to 1.0 Very high >1.0 Excessively high Classification for nitrate Grade limit (mg NO3/l) Average Description: 5 to 10 Low >10 to 20 Moderately low >20 to30 Moderate >30 to 40 High >40 Very high. 2009 was the final year of the scheme.
Allweddeiriau
Allweddair
Allweddair
Allweddair
System Cyfeirio Gofodol
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- NONE
Cynnwys
Gwybodaeth Cynnwys
Proffil CNC
Elfennau CNC
Cyfyngiadau
Cyfyngiadau
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There are no access restrictions on this data. NRW may release, publish or disseminate it freely.
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© CNC/NRW Data may be re-used under the terms of the Open Government Licence providing it is done so, acknowledging both the source and NRW's copyright. It is the recipient's responsibility to ensure the data is fit for the intended purpose. Attribution statement: Contains Natural Resources Wales information © Natural Resources Wales and Database Right. All rights Reserved.
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- Dynodydd Ffeil
- 4f4c4942-4343-5764-6473-313136333236 XML
- Laith Metadata
- English
- Dynodydd Rhiant
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Historic General Quality Assessment (GQA) Headline Indicators of Water Courses
NRW_DS118585
- Math o adnodd
- Dataset
- Dyddiad Metadata
- 2024-05-31T09:14:21.511Z
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- NRW
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1.0