Iwerne Water Body

Moderate ecological status

Attributes

  • Water Body IDGB108043016010
  • Water Body TypeRiver
  • Hydromorphological designationnot designated artificial or heavily modified
  • NGRST8610111720
  • Catchment area19.316 km2
  • Surveillance Water BodyNo
  • Length6.32 km
  • Catchment area1931.61 ha

Classifications

Classification Item20192022
EcologicalModerateModerate
Biological quality elementsModerateModerate
InvertebratesHighHigh
Macrophytes and Phytobenthos CombinedModerateModerate
Macrophytes Sub ElementModerateModerate
Physico-chemical quality elementsModerateModerate
Ammonia (Phys-Chem)HighHigh
Dissolved oxygenHighHigh
PhosphatePoorPoor
TemperatureHighHigh
pHHighHigh
Hydromorphological Supporting ElementsSupports goodSupports good
Hydrological RegimeSupports goodSupports good
MorphologySupports goodSupports good
ChemicalFailDoes not require assessment
Priority hazardous substancesFailDoes not require assessment
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
Priority substancesGoodDoes not require assessment
Cypermethrin (Priority)Good
FluorantheneGood
Other PollutantsDoes not require assessmentDoes 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
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
RNAGPoint sourceSewage discharge (continuous)Water IndustryPhosphateDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryMacrophytes and Phytobenthos CombinedDetails
RNAGDiffuse sourcePoor nutrient managementAgriculture and rural land managementMacrophytes and Phytobenthos CombinedDetails
RNAGDiffuse sourcePoor nutrient managementAgriculture and rural land managementPhosphateDetails

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 management0000010
Industry0000000
Mining and quarrying0000000
Navigation0000000
Urban and transport0000000
Water Industry0100000
Local & central government0000000
Domestic general public0000000
Recreation0000000
Waste treatment and disposal0000000
Other0000000
No sector responsible0000000
Sector under investigation0000000
Total0100010

Objectives

Classification ItemStatusYearReasons
EcologicalModerate2015Disproportionately expensive: Disproportionate burdens
Biological quality elementsGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
InvertebratesGood2015
Macrophytes and Phytobenthos CombinedGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Physico-chemical quality elementsModerate2015Disproportionately expensive: Disproportionate burdens
Ammonia (Phys-Chem)Good2015
Dissolved oxygenGood2015
PhosphateModerate2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
TemperatureGood2015
pHGood2015
Hydromorphological Supporting ElementsSupports good2015
Hydrological RegimeSupports good2015
Supporting elements (Surface Water)Not assessed2015
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 CompoundsGood2040Natural conditions: Chemical status recovery time
Perfluorooctane sulphonate (PFOS)Good2015
Polybrominated diphenyl ethers (PBDE)Good2063Natural conditions: Chemical status recovery time
Priority substancesGood2015
Cypermethrin (Priority)Good2015
FluorantheneGood2015
Other PollutantsDoes not require assessment2015

Protected areas

PA NameIdDirectiveMore information
South WessexG151Nitrates 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
8604 86042014, 2009, 2012, 20132014, 2016, 2015
RIVER IWERNE AT STOURPAINE 503411052010, 2011, 2014, 2009, 20122016, 2014, 2015
RIVER IWERNE AT SHROTON FROG LANE 503411502016, 2015
RIVER IWERNE AT OYLES MILL 503411562009

Upstream water bodies

    Downstream water bodies