Bristol Avon (By Bk to Netham Weir) Water Body

Moderate ecological status

Attributes

  • Water Body IDGB109053027371
  • Water Body TypeRiver
  • Hydromorphological designationheavily modified
  • NGRST7145866047
  • Catchment area85.204 km2
  • Surveillance Water BodyYes
  • Length32.383 km
  • Catchment area8520.409 ha

Classifications

Classification Item20192022
EcologicalModerateModerate
Biological quality elementsGoodGood
InvertebratesGoodGood
Macrophytes and Phytobenthos CombinedGoodGood
Macrophytes Sub ElementGoodGood
Phytobenthos Sub ElementGoodGood
Physico-chemical quality elementsModerateModerate
Ammonia (Phys-Chem)GoodGood
Dissolved oxygenHighHigh
PhosphateModerateModerate
TemperatureGoodGood
pHHighHigh
Hydromorphological Supporting ElementsSupports goodSupports good
Hydrological RegimeSupports goodSupports good
Supporting elements (Surface Water)ModerateModerate
Mitigation Measures AssessmentModerate or lessModerate or less
Specific pollutantsHighHigh
ArsenicHighHigh
ChlorothalonilHighHigh
CopperHighHigh
DiazinonHighHigh
DimethoateHighHigh
IronHighHigh
ManganeseHighHigh
PendimethalinHighHigh
ZincHighHigh
ChemicalFailDoes not require assessment
Priority hazardous substancesFailDoes not require assessment
Benzo(a)pyreneGood
Benzo(b)fluorantheneGood
Benzo(g-h-i)peryleneGood
Benzo(k)fluorantheneGood
Cadmium and Its CompoundsGood
Dioxins and dioxin-like compoundsGood
Heptachlor and cis-Heptachlor epoxideGood
Hexabromocyclododecane (HBCDD)Good
HexachlorobenzeneGood
HexachlorobutadieneGood
HexachlorocyclohexaneGood
Mercury and Its CompoundsFail
PentachlorobenzeneGood
Perfluorooctane sulphonate (PFOS)Fail
Polybrominated diphenyl ethers (PBDE)Fail
QuinoxyfenGood
Priority substancesGoodDoes not require assessment
AclonifenGood
AlachlorGood
BifenoxGood
CybutryneGood
Cypermethrin (Priority)Good
Dichlorvos (Priority)Good
FluorantheneGood
Lead and Its CompoundsGood
Nickel and Its CompoundsGood
TerbutrynGood
Other PollutantsGoodDoes not require assessment
Aldrin, Dieldrin, Endrin & IsodrinGood
para - para DDTGood

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

Investigations into classification status

No data to show

Reasons for not achieving good (RNAG) and reasons for deterioration (RFD)

All reasons (RFDs and RNAGs) attributed to the classification elements in this water body.

Reason TypeSWMIActivityCategoryClassification ElementMore information
RNAGPhysical modificationOther (not in list, must add details in comments)Urban and transportMitigation Measures AssessmentDetails
RNAGPhysical modificationOther (not in list, must add details in comments)Local and Central GovernmentMitigation Measures AssessmentDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryPhosphateDetails
RNAGPhysical modificationOther (not in list, must add details in comments)RecreationMitigation Measures AssessmentDetails
RNAGUnknown (pending investigation)Unknown (pending investigation)Sector under investigationPerfluorooctane sulphonate (PFOS)Details
RNAGmeasures delivered to address reason, awaiting recoveryNot applicableNo sector responsiblePolybrominated diphenyl ethers (PBDE)Details
RNAGmeasures delivered to address reason, awaiting recoveryNot applicableNo sector responsibleMercury and Its CompoundsDetails

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 issuePhysical modificationsPollution from waste waterPollution from towns, cities and transportChanges to the natural flow and level of waterInvasive non-native speciesPollution from rural areasPollution from abandoned mines
Agriculture and rural land management0000000
Industry0000000
Mining and quarrying0000000
Navigation0000000
Urban and transport1000000
Water Industry0100000
Local & central government1000000
Domestic general public0000000
Recreation1000000
Waste treatment and disposal0000000
Other0000000
No sector responsible0000000
Sector under investigation0000000
Total3100000

Objectives

Classification ItemStatusYearReasons
EcologicalGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Biological quality elementsGood2015
InvertebratesGood2015
Macrophytes and Phytobenthos CombinedGood2015
Physico-chemical quality elementsGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Ammonia (Phys-Chem)Good2015
Dissolved oxygenGood2015
PhosphateGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
TemperatureGood2015
pHGood2015
Hydromorphological Supporting ElementsSupports good2015
Hydrological RegimeSupports good2015
Supporting elements (Surface Water)Good2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Mitigation Measures AssessmentGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Specific pollutantsHigh2015
ArsenicHigh2015
ChlorothalonilHigh2015
CopperHigh2015
DiazinonHigh2015
DimethoateHigh2015
IronHigh2015
ManganeseHigh2015
PendimethalinHigh2015
ZincHigh2015
ChemicalGood2063Natural conditions: Chemical status recovery time;
Technically infeasible: No known technical solution is available
Priority hazardous substancesGood2063Natural conditions: Chemical status recovery time;
Technically infeasible: No known technical solution is available
Benzo (b) and (k) fluorantheneGood2015
Benzo (ghi) perelyene and indeno (123-cd) pyreneGood2015
Benzo(a)pyreneGood2015
Benzo(b)fluorantheneGood2015
Benzo(g-h-i)peryleneGood2015
Benzo(k)fluorantheneGood2015
Cadmium and Its CompoundsGood2015
Dioxins and dioxin-like compoundsGood2015
Heptachlor and cis-Heptachlor epoxideGood2015
Hexabromocyclododecane (HBCDD)Good2015
HexachlorobenzeneGood2015
HexachlorobutadieneGood2015
HexachlorocyclohexaneGood2015
Mercury and Its CompoundsGood2040Natural conditions: Chemical status recovery time
PentachlorobenzeneGood2015
Perfluorooctane sulphonate (PFOS)Good2039Technically infeasible: No known technical solution is available
Polybrominated diphenyl ethers (PBDE)Good2063Natural conditions: Chemical status recovery time
QuinoxyfenGood2015
Priority substancesGood2015
AclonifenGood2015
AlachlorGood2015
BifenoxGood2015
CybutryneGood2015
Cypermethrin (Priority)Good2015
Dichlorvos (Priority)Good2015
FluorantheneGood2015
Lead and Its CompoundsGood2015
Nickel and Its CompoundsGood2015
TerbutrynGood2015
Other PollutantsGood2015
Aldrin, Dieldrin, Endrin & IsodrinGood2015
para - para DDTGood2015

Protected areas

PA NameIdDirectiveMore information
River Avon (Bristol)UKENRI77Urban Waste Water Treatment Directive

Monitoring sites which have been used to classify this water body

Shows which sites were used for classification for which years within each cycle.

Monitoring SiteCycle 1Cycle 2Cycle 3
BRISTOL AVON U/S HANHAM WEIR Z10105012014, 2015, 2013, 2016, 20192019
BRISTOL AVON AT KEYNSHAM MONITOR Z10107062016, 2019, 20152019
BRISTOL AVON U/S BOYD CONFLUENCE Z101080420192019
7747 77472015, 2016
7754 77542015, 2013, 2016
156047 1560472016, 2015, 2019, 2014, 20132019
164744 1647442016, 2015, 2019, 20142019
7743 77432015, 2014, 2016

Downstream water bodies