Irwell (Rossendale STW to Roch) Water Body

Moderate ecological status

Attributes

  • Water Body IDGB112069064620
  • Water Body TypeRiver
  • Hydromorphological designationheavily modified
  • NGRSD7944213659
  • Catchment area4289.22 ha
  • Length32.756 km
  • Catchment area42.892 km2
  • Surveillance Water BodyNo

Classifications

Classification Item20192022
EcologicalModerateModerate
Biological quality elementsModerateModerate
InvertebratesModerateModerate
Macrophytes and Phytobenthos CombinedModerateModerate
Phytobenthos Sub ElementModerateModerate
Physico-chemical quality elementsModerateModerate
Ammonia (Phys-Chem)HighHigh
Biochemical Oxygen Demand (BOD)High
Dissolved oxygenHighHigh
PhosphateModerateModerate
TemperatureHighHigh
pHHighHigh
Hydromorphological Supporting ElementsSupports goodSupports good
Hydrological RegimeSupports goodSupports good
Supporting elements (Surface Water)ModerateModerate
Mitigation Measures AssessmentModerate or lessModerate or less
Specific pollutantsHighHigh
IronHighHigh
PermethrinHighHigh
ChemicalFailDoes not require assessment
Priority hazardous substancesFailDoes not require assessment
AnthraceneGood
Benzo(a)pyreneGood
Dioxins and dioxin-like compoundsGood
Heptachlor and cis-Heptachlor epoxideGood
Hexabromocyclododecane (HBCDD)Good
HexachlorobenzeneGood
HexachlorobutadieneGood
Mercury and Its CompoundsFail
Perfluorooctane sulphonate (PFOS)Good
Polybrominated diphenyl ethers (PBDE)Fail
Tributyltin CompoundsGood
Priority substancesFailDoes not require assessment
Cypermethrin (Priority)Fail
FluorantheneGood
Other PollutantsDoes not require assessmentDoes not require assessment

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

Investigations into classification status

Classification ElementCycleYearStatusOutcome
Invertebrates22014GoodVery certain there is a problem

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
RFDMonitoring Site Changed (RFD only)Not applicableNo sector responsibleInvertebratesDetails
RNAGPoint sourceSewage discharge (intermittent)Water IndustryInvertebratesDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryInvertebratesDetails
RNAGDiffuse sourceUrbanisation - urban developmentUrban and transportMacrophytes and Phytobenthos CombinedDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryInvertebratesDetails
RNAGDiffuse sourcePoor Livestock ManagementAgriculture and rural land managementMacrophytes and Phytobenthos CombinedDetails
RNAGPoint sourceSewage discharge (intermittent)Water IndustryInvertebratesDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryMacrophytes and Phytobenthos CombinedDetails
RNAGmeasures delivered to address reason, awaiting recoveryNot applicableNo sector responsibleMercury and Its CompoundsDetails
RNAGmeasures delivered to address reason, awaiting recoveryNot applicableNo sector responsiblePolybrominated diphenyl ethers (PBDE)Details
RNAGDiffuse sourceUrbanisation - urban developmentUrban and transportPhosphateDetails
RNAGPhysical modificationOther (not in list, must add details in comments)Sector under investigationMitigation Measures AssessmentDetails
RNAGPhysical modificationOther (not in list, must add details in comments)Sector under investigationMitigation Measures AssessmentDetails
RNAGDiffuse sourcePoor Livestock ManagementAgriculture and rural land managementPhosphateDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryPhosphateDetails
RNAGPhysical modificationOther (not in list, must add details in comments)Sector under investigationMitigation Measures AssessmentDetails

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 transport0000000
Water Industry0600000
Local & central government0000000
Domestic general public0000000
Recreation0000000
Waste treatment and disposal0000000
Other0000000
No sector responsible0000000
Sector under investigation3000000
Total3600000

Objectives

Classification ItemStatusYearReasons
EcologicalModerate2027 - Low confidenceDisproportionately expensive: Disproportionate burdens;
Natural conditions: Ecological recovery time;
Technically infeasible: No known technical solution is available
Biological quality elementsModerate2027 - Low confidenceDisproportionately expensive: Disproportionate burdens;
Natural conditions: Ecological recovery time
InvertebratesGood2015
Macrophytes and Phytobenthos CombinedModerate2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Physico-chemical quality elementsModerate2015Disproportionately expensive: Disproportionate burdens;
Technically infeasible: No known technical solution is available
Ammonia (Phys-Chem)Good2015
Dissolved oxygenGood2015
PhosphateModerate2027 - Low confidenceDisproportionately expensive: Disproportionate burdens;
Technically infeasible: No known technical solution is available
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
IronHigh2015
PermethrinHigh2015
ChemicalGood2063Disproportionately expensive: Disproportionate burdens;
Natural conditions: Chemical status recovery time
Priority hazardous substancesGood2063Natural conditions: Chemical status recovery time
AnthraceneGood2015
Benzo(a)pyreneGood2015
Dioxins and dioxin-like compoundsGood2015
Heptachlor and cis-Heptachlor epoxideGood2015
Hexabromocyclododecane (HBCDD)Good2015
HexachlorobenzeneGood2015
HexachlorobutadieneGood2015
Mercury and Its CompoundsGood2040Natural conditions: Chemical status recovery time
Perfluorooctane sulphonate (PFOS)Good2015
Polybrominated diphenyl ethers (PBDE)Good2063Natural conditions: Chemical status recovery time
Tributyltin CompoundsGood2015
Priority substancesGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Cypermethrin (Priority)Good2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
FluorantheneGood2015
Other PollutantsDoes not require assessment2015

Protected areas

PA NameIdDirectiveMore information
River IrwellUKENRI94Urban 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
DEARDEN BROOK ABOVE CONF WITH IRWELL 880021132011, 2009, 2012, 20102015, 2016
67803 678032009, 20142019, 2015, 2016, 20142019
RIVER IRWELL D/S OF RIVER OGDEN 880021102009, 2011, 2014, 2012, 2010, 20132014, 2015, 2019, 2013, 20162022, 2019
68867 688672010, 2009, 2014, 20112016, 2015, 2014
MERSEY/IRWELL/IWIR07/ 63672010
178005 17800520192019
MERSEY/IRWELL/IWIR08/ 104182009
178006 17800620192019
178226 17822620192019
67591 675912009
67801 678012009
HOLCOMBE BROOK ABOVE CONF WITH IRWELL 880021202011, 2009, 2012, 2010
67804 678042010, 2009, 2011
RIVER IRWELL AT CHEST WHEEL BRIDGE 8800212320192019
ELTON BROOK U/S OF RIVER IRWELL 880021362009, 2011, 2012, 2010
RIVER IRWELL ABOVE WARTH WEIR 880021402011, 2009, 2014, 2012, 2010, 20132014, 2015, 2013, 2016
MERSEY/IRWELL/IWIR09/ 133792010
PIGS LEE BROOK U/S OF RIVER IRWELL 880021282009
MERSEY/IRWELL/IWIR10/ 104142014, 2012, 2010, 2013, 2009, 20112014, 2013
RIVER IRWELL U/S OF BURY S.T.W 880219172014, 2012, 20132015, 2013, 2016, 20192019
RIVER IRWELL AT IRWELL VALE BRIDGE 880020962009, 2014, 2012, 2010, 2013
RIVER IRWELL AT STUBBINS BRIDGE 880021122011, 2009, 2010, 2012, 20132015, 2016, 20192019

Downstream water bodies