Avon Bristol and Somerset North Streams Management Catchment

About

The river basin is encircled by the hills of the Cotswolds, Salisbury Plain and the Mendips. The river runs through gentle pastoral landscapes and old towns such as Bradford and Bath before emerging through the Clifton Gorge at Bristol into the Severn Estuary at Avonmouth. A number of rivers in the catchment drain directly to the Severn Estuary including the Little Avon in Gloucestershire and the North Somerset Streams. The upper reaches of the catchment are very rural with significant arable agricultural activity on the higher ground and livestock more common on the lowland pasture. The main river is slow moving lowland clay river which has been modified by impoundment, land drainage, flood alleviation engineering and by intensive agriculture in the flood plain. Avonmouth is a key industrial area and port. Historically the river and many tributaries were impounded to serve the many watermills along its length, subsequent siltation has resulted in changes to depth and plant communities. The Severn estuary is an internationally important site for conservation and there are 66 Sites of Special Scientific Interest across the catchment, and 8 of these are directly related to rivers. The catchment supports a diverse fish fauna and is highly regarded as a coarse fishery. There are major potable water supply groundwater abstractions located in the Malmesbury area and from surface waters lower down the cathment. Most of the licensed water abstractions in this catchment are for public supply, including several large reservoirs (Blagdon and Chew Valley). The Bristol Avon and North Somerset Streams management catchment has been divided into 16 operational catchments (4 surface water operational catchments). The operational catchments have distinct characteristics and pressures, and require a different mix of measures to achieve long-term objectives for the water environment and reduce the risks of flooding. We are proposing amending the Bristol Avon and North Somerset Streams Defra Management catchment boundary so the River Axe will now be included in the South and West Somerset Defra Management Catchment (as part of the Brue and Axe Operational Catchment).

River Congresbury Yeo

Classifications data for Avon Bristol and Somerset North Streams Management Catchment

Number of water bodies

The number of water bodies in the river basin district. It shows whether these are natural, artificial (such as canals and reservoirs) or have been modified ('heavily modified') for particular uses.

Water body categoriesNaturalArtificialHeavily modifiedTotal
River, canals and surface water transfers79421104
Lake0022
Coastal0000
Estuarine0000
Groundwater0000
Total79423106

Ecological status for surface waters

Table summarises the current ecological status of surface water bodies. Water bodies are classified as being at high, good, moderate, poor or bad ecological status or potential.

Ecological status or potentialBadPoorModerateGoodHighTotal
Number of water bodies02271130106
Number of water body elements361121118633936

Chemical status for surface waters

Table summarises the current chemical status of water bodies. These are classified as being at good or fail.

Chemical statusFailGoodTotal
Number of water bodies1060106
Number of water body elements23711351372

Why do all water bodies have a chemical status of fail?

Quantitative status for groundwater

Table summarises the quantitative status of groundwater water bodies. These are classified as being at good or poor.

Quantitative statusPoorGoodTotal
Number of water bodies000
Number of water body elements000

Chemical status for groundwater

Table summarises the chemical status of groundwater water bodies. These are classified as being at good or poor.

Chemical statusPoorGoodTotal
Number of water bodies000
Number of water body elements000

Challenges data for Avon Bristol and Somerset North Streams Management Catchment

Reasons for not achieving good status by business sector

The issues preventing waters reaching good status and the sectors identified as contributing to them. The numbers in the table are individual counts of the reasons for not achieving good status with a confidence status of 'confirmed' and 'probable', where the latest classification is less than good status. There may be more than one reason in a single water body. Note, table does not include reasons for deterioration.

Significant water management issueChanges to the natural flow and level of waterInvasive non-native speciesPhysical modificationsPollution from abandoned minesPollution from rural areasPollution from towns, cities and transportPollution from waste water
Agriculture and rural land management1013014400
Domestic general public0000031
Industry0010050
Local & central government00190000
Mining and quarrying0012000
Navigation0000000
No sector responsible0300000
Other00200000
Recreation0020000
Sector under investigation3040000
Urban and transport001500210
Waste treatment and disposal0000011
Water Industry120700374
Total1638221443376

Objectives data for Avon Bristol and Somerset North Streams Management Catchment

Ecological status or potential objectives for surface water bodies

Table summarises the ecological status and ecological potential objectives set for water bodies in the river basin management plan. Each water body is only counted once in this table. Each water body objective consists of a target status and a date when it was, or is expected to be, met.

StatusBadPoorModerateGoodHighTotal
By 2015001310023
By 2021000404
By 202700772079
Total0020860106

79 of the "by 2027" objectives are low confidence

Chemical status objectives for surface water bodies

Including those with less stringent objectives and extended deadlines

StatusFailGoodTotal
By 20630106106
Total0106106

0 of the "by 2027" objectives are low confidence

Quantitative status objectives for groundwater

Including those with less stringent objectives and extended deadlines

StatusPoor
GoodTotal
Total000

0 of the "by 2027" objectives are low confidence

Chemical status objectives for groundwater

Including those with less stringent objectives and extended deadlines

StatusPoor
GoodTotal
Total000

0 of the "by 2027" objectives are low confidence

Summary Statistics data for Avon Bristol and Somerset North Streams Management Catchment

Ecological status and potential

Summary statisticRivers, Canals and SWTsLakesEstuariesCoastalSurface Waters Combined
% of water bodies at good or better ecological status/potential13%0%12%
% of biological elements, phys-chem elements and specific pollutants at good or better status79%56%79%
% of water bodies with an objective of good ecological status/potential or better81%100%81%
% of biological elements, phys-chem elements and Specific Pollutants with an objective of good status or better96%100%96%

Chemical

Summary statisticRivers, Canals and SWTsLakesEstuariesCoastalSurface Waters Combined
% of water bodies at good chemical status0%0%0%
% of chemical elements at good status83%86%83%
% of water bodies at good chemical status without uPBT98%100%98%
% of chemical elements at good status without uPBTGreater than 99%100%Greater than 99%
% of water bodies with an objective of good chemical status100%100%100%
% of chemical elements with an objective of good100%100%100%
% of water bodies with an objective of good chemical status without uPBT100%100%100%
% of chemical elements with an objective of good without uPBTs100%100%100%