Grand Union Canal, Uxbridge to Hanwell Locks, Slough Arm, Paddington Arm Water Body

Moderate ecological status

Attributes

  • Water Body IDGB70610078
  • Water Body TypeCanal
  • Hydromorphological designationartificial
  • NGRTQ0520781531
  • Length45.496 km
  • Surveillance Water BodyNo

Classifications

Classification Item2019
EcologicalModerate
Physico-chemical quality elementsModerate
Acid Neutralising CapacityHigh
Ammonia (Phys-Chem)High
Dissolved oxygenHigh
PhosphateModerate
TemperatureHigh
pHHigh
Supporting elements (Surface Water)Moderate
Mitigation Measures AssessmentModerate or less
ChemicalFail
Priority hazardous substancesFail
Benzo(a)pyreneGood
Dioxins and dioxin-like compoundsGood
Heptachlor and cis-Heptachlor epoxideGood
Hexabromocyclododecane (HBCDD)Good
HexachlorobenzeneGood
HexachlorobutadieneGood
Mercury and Its CompoundsGood
Perfluorooctane sulphonate (PFOS)Good
Polybrominated diphenyl ethers (PBDE)Fail
Priority substancesGood
FluorantheneGood
Other PollutantsDoes not require assessment

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
RFDHigh to Good deterioration, no action required (RFD only)Not applicableNo sector responsibleTemperatureDetails
RNAGPoint sourcePrivate Sewage TreatmentUrban and transportPhosphateDetails
RNAGPoint sourceSewage discharge (intermittent)Water IndustryPhosphateDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryPhosphateDetails
RNAGPoint sourceMisconnectionsDomestic General PublicPhosphateDetails
RNAGPhysical modificationOther (not in list, must add details in comments)RecreationMitigation Measures AssessmentDetails
RNAGDiffuse sourceUrbanisation - urban developmentUrban and transportPhosphateDetails
RNAGUnknown (pending investigation)Unknown (pending investigation)Sector under investigationPolybrominated diphenyl ethers (PBDE)Details

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 transport0010000
Water Industry0200000
Local & central government0000000
Domestic general public0000000
Recreation1000000
Waste treatment and disposal0000000
Other0000000
No sector responsible0000000
Sector under investigation0000000
Total1210000

Objectives

Classification ItemStatusYearReasons
EcologicalModerate2015Disproportionately expensive: Disproportionate burdens;
Disproportionately expensive: Unfavourable balance of costs and benefits
Biological quality elementsNot assessed2015
Physico-chemical quality elementsModerate2015Disproportionately expensive: Unfavourable balance of costs and benefits
Acid Neutralising CapacityGood2015
Ammonia (Phys-Chem)Good2015
Dissolved oxygenGood2015
PhosphateModerate2015Disproportionately expensive: Unfavourable balance of costs and benefits
TemperatureGood2015
pHGood2015
Hydromorphological Supporting ElementsNot assessed2015
Supporting elements (Surface Water)Good2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Mitigation Measures AssessmentGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Specific pollutantsNot assessed2015
ChemicalGood2063Natural conditions: Chemical status recovery time
Priority hazardous substancesGood2063Natural conditions: Chemical status recovery time
Benzo(a)pyreneGood2015
Dioxins and dioxin-like compoundsGood2015
Heptachlor and cis-Heptachlor epoxideGood2015
Hexabromocyclododecane (HBCDD)Good2015
HexachlorobenzeneGood2015
HexachlorobutadieneGood2015
Mercury and Its CompoundsGood2015
Perfluorooctane sulphonate (PFOS)Good2015
Polybrominated diphenyl ethers (PBDE)Good2063Natural conditions: Chemical status recovery time
Priority substancesGood2015
FluorantheneGood2015
Other PollutantsDoes not require assessment2015

Protected areas

No data to show

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
G.U.C. UPSTREAM OF LOCK 97 PGUR00212014, 2012, 2011, 2010, 20132014, 2015, 2013, 2016, 20192019
G.U.C. AT HORTON ROAD BRIDGE PGUR00072014, 2012, 2011, 2010, 20132014, 2015, 2013, 2016, 20192019

Upstream water bodies

    Downstream water bodies