Identification

Title

Historic GQA Headline Indicators of Water Courses - Nutrients - phosphate GQA grades 2009 (England)

Alternative title(s)

Abstract

GQA Headline Indicators of Water Courses - Nutrients - phosphate GQA grades 2009 (England)'. The General Quality Assessment Headline Indicator scheme (GQAHI) was the Environment Agency's national method for creating a water quality indicator based on rivers and canals in England. This was a reduced network compared to the original GQA network used in England from 1990 to 2006. The Nutrients GQAHI scheme had over 3000 sampling sites which provide information for approximately 22500 km of watercourses. 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. 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 Very low >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 Very low >5 to 10 Low >10 to 20 Moderately low >20 to30 Moderate >30 to 40 High >40 Very high 2009 is the final year of the scheme. Attribution statement: © Environment Agency copyright and/or database right 2019. All rights reserved

Resource type

dataset

Resource locator

https://environment.data.gov.uk/api/file/download?fileDataSetId=642448e7-1fe1-45de-abb0-4c92d67b19a7&fileName=Historic_GQA_Headline_Indicators_of_Water_Courses_-_Nutrients_-_phosphate_GQA_grades_2009_(England).zip

protocol: http

name: Historic_GQA_Headline_Indicators_of_Water_Courses_-_Nutrients_-_phosphate_GQA_grades_2009_(England).zip

description: Historic_GQA_Headline_Indicators_of_Water_Courses_-_Nutrients_-_phosphate_GQA_grades_2009_(England).zip download on Defra Data Services Platform

Unique resource identifier

code

649131de-d465-11e4-b779-f0def148f590

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

http://www.opengis.net/def/crs/EPSG/0/27700

Classification of spatial data and services

Topic category

environment

inlandWaters

Keywords

Keyword set

keyword value

environment

inlandWaters

Keyword set

keyword value

water quality

originating controlled vocabulary

title

reference date

date type

publication

effective date

2010-01-13

Keyword set

keyword value

monitoring technique

originating controlled vocabulary

title

reference date

date type

publication

effective date

2010-01-13

Keyword set

keyword value

monitoring data

originating controlled vocabulary

title

reference date

date type

publication

effective date

2010-01-13

Geographic location

West bounding longitude

-6.236

East bounding longitude

2.072

North bounding latitude

55.816

South bounding latitude

49.943

Temporal reference

Temporal extent

Begin position

1990-01-01

End position

2009-12-31

Dataset reference date

date type

creation

effective date

2010-01-01

Frequency of update

notPlanned

Quality and validity

Lineage

The Nutrients GQAHI described quality in terms of nutrients specifically Phosphate and Nitrates. At each sample points twelve water column samples were collected per annum and each assessment was based on a three year period. Data is represented as river stretches and stored in an zipped access database in four tables on the O drive (Environment Agency's shared drive).

Conformity

Data format

name of format

Proprietary format | ESRI, Intergraph, MS Access (MDB)

version of format

Unknown

Constraints related to access and use

Constraint set

Use constraints

Open Government Licence

Constraint set

Limitations on public access

There are no public access constraints to this data. Use of this data is subject to the licence identified.

Constraint set

Use constraints

Constraint set

Limitations on public access

There are no public access constraints to this data. Use of this data is subject to the licence identified.

Responsible organisations

Responsible party

organisation name

Environment Agency

email address

DSPcustomerforum@environment-agency.gov.uk

web address

https://environment.data.gov.uk/support

description: Defra Data Services Forum

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact

organisation name

Environment Agency

email address

DSPcustomerforum@environment-agency.gov.uk

responsible party role

pointOfContact

Metadata date

2024-01-05

Metadata language