Norton, L.; Dunbar, M.; Greene, S.; Scholefield, P.A.

Headwater stream quality for Britain

Data consist of modelled estimates of observed/expected Biological Monitoring Working Party (an index for measuring the biological quality of rivers using selected families of macroinvertebrates as biological indicators) scores for freshwater streams across Great Britain (GB). The BMWP scores (1-10) are based on the principle that macroinvertebrates differ in their perceived sensitivity or tolerance to organic pollution (i.e. nutrient enrichment). Values greater than 1 indicate high water quality. Data pooled across two survey years (1998 and 2007) was used to model the relationships between headwater stream quality and catchment/stream characteristics for headwater streams across GB based on known relationships for headwater streams in Countryside Survey squares. Modelled estimates of stream water quality were based on a Boosted Regression Tree modelling approach .

Publication date: 2016-02-04

Get the data

This dataset is made available under the terms of the Open Government Licence

Format of the data: Esri shapefile

You must cite: Norton, L.; Dunbar, M.; Greene, S.; Scholefield, P.A. (2016). Headwater stream quality for Britain. NERC Environmental Information Data Centre.


© Natural England

The following organisations must be acknowledged by users of this dataset: NERC, Defra, the National Assembly for Wales, the Scottish Government, Natural England, Countryside Council for Wales, Scottish Natural Heritage.


Study area
Temporal extent
1998-05-01    to    2007-10-31

Provenance & quality

This national model was developed following initial work under the Countryside Survey Integrated Assessment which investigated the relationships between water quality and the characteristics of the 1km squares in which they were located.

Correspondence/contact details

Dr. Lisa Norton
UK Centre for Ecology & Hydrology
Lancaster Environment Centre, Library Avenue, Bailrigg


Norton, L.
Centre for Ecology & Hydrology
Dunbar, M.
Centre for Ecology & Hydrology
Greene, S.
Centre for Ecology & Hydrology
Scholefield, P.A.
Centre for Ecology & Hydrology

Other contacts

NERC EDS Environmental Information Data Centre
NERC Environmental Information Data Centre
Rights Holder

Additional metadata

Topic categories
Countryside Survey,  GB,  headwater streams,  modelled,  Modelling water quality
Spatial representation type
Spatial reference system
OSGB 1936 / British National Grid
Last updated
25 June 2021 18:43