Atherfield Stream Water Body

Moderate ecological status


  • Water Body IDGB107101005920
  • Water Body TypeRiver
  • Hydromorphological designationheavily modified
  • NGRSZ4611480242
  • Catchment area11.166 km2
  • Surveillance Water BodyNo
  • Catchment area1116.567 ha
  • Length4.421 km


Classification Item20192022
Biological quality elementsModerateModerate
Macrophytes and Phytobenthos CombinedHighHigh
Phytobenthos Sub ElementHighHigh
Physico-chemical quality elementsHighHigh
Ammonia (Phys-Chem)HighHigh
Dissolved oxygenHighHigh
Hydromorphological Supporting ElementsSupports goodSupports good
Hydrological RegimeSupports goodSupports good
Supporting elements (Surface Water)ModerateModerate
Mitigation Measures AssessmentModerate or lessModerate or less
ChemicalFailDoes not require assessment
Priority hazardous substancesFailDoes not require assessment
Dioxins and dioxin-like compoundsGood
Heptachlor and cis-Heptachlor epoxideGood
Hexabromocyclododecane (HBCDD)Good
Mercury and Its CompoundsGood
Perfluorooctane sulphonate (PFOS)Good
Polybrominated diphenyl ethers (PBDE)Fail
Priority substancesGoodDoes not require assessment
Cypermethrin (Priority)Good
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
RNAGDiffuse sourcePoor soil managementAgriculture and rural land managementInvertebratesDetails
RNAGPhysical modificationOther (not in list, must add details in comments)Local and Central GovernmentMitigation Measures AssessmentDetails
RNAGNaturalNatural mineralisationNo sector responsibleInvertebratesDetails
RNAGNaturalDroughtNo sector responsibleInvertebratesDetails

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
Mining and quarrying0000000
Urban and transport0000000
Water Industry0000000
Local & central government1000000
Domestic general public0000000
Waste treatment and disposal0000000
No sector responsible0000000
Sector under investigation0000000


Classification ItemStatusYearReasons
EcologicalGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens;
Disproportionately expensive: Unfavourable balance of costs and benefits
Biological quality elementsModerate2015Disproportionately expensive: Unfavourable balance of costs and benefits
InvertebratesModerate2015Disproportionately expensive: Unfavourable balance of costs and benefits
Macrophytes and Phytobenthos CombinedGood2015
Physico-chemical quality elementsGood2015
Ammonia (Phys-Chem)Good2015
Dissolved oxygenGood2015
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 pollutantsNot assessed2015
ChemicalGood2063Natural conditions: Chemical status recovery time
Priority hazardous substancesGood2063Natural conditions: Chemical status recovery time
Dioxins and dioxin-like compoundsGood2015
Heptachlor and cis-Heptachlor epoxideGood2015
Hexabromocyclododecane (HBCDD)Good2015
Mercury and Its CompoundsGood2015
Perfluorooctane sulphonate (PFOS)Good2015
Polybrominated diphenyl ethers (PBDE)Good2063Natural conditions: Chemical status recovery time
Priority substancesGood2015
Cypermethrin (Priority)Good2015
Other PollutantsDoes not require assessment2015

Protected areas

PA NameIdDirectiveMore information
Solent And Dorset CoastUK9020330Special Protection AreaNatural England
South Wight MaritimeUK0030061Special Area of ConservationNatural England
Atherfield Stream NVZS529Nitrates 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
43289 432892010, 2009, 20112016, 2019, 2015, 2014, 20132022, 2019
ATHERFIELD STREAM SHEP CHINE Y00043162009, 20142019, 2014, 2015, 20162019
142991 1429912014

Upstream water bodies

    Downstream water bodies