Stewartby Lake Water Body

Moderate ecological status

Attributes

  • Water Body IDGB30539450
  • Water Body TypeLake
  • Hydromorphological designationartificial
  • NGRTL0075542402
  • Altitude35 m
  • Mean depth6.4 m
  • Surveillance Water BodyNo
  • Surface area0.782 km2
  • Surface area78.163 ha
  • Catchment area2779.75 ha

Classifications

Classification Item20192022
EcologicalModerateModerate
Biological quality elementsModerateModerate
Macrophytes and Phytobenthos Combined
Macrophytes Sub ElementPoorPoor
PhytoplanktonModerateModerate
Physico-chemical quality elementsModerateModerate
SalinityHighHigh
Total NitrogenBadPoor
Total PhosphorusPoorModerate
Hydromorphological Supporting ElementsSupports goodSupports good
Hydrological RegimeSupports goodSupports good
Supporting elements (Surface Water)ModerateModerate
Expert JudgementModerateModerate
Mitigation Measures AssessmentGoodGood
Specific pollutantsHighHigh
CopperHighHigh
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 CompoundsGood
Perfluorooctane sulphonate (PFOS)Fail
Polybrominated diphenyl ethers (PBDE)Fail
Priority substancesGoodDoes not require assessment
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
RNAGOther pressuresInternal nutrient load (lakes only)No sector responsiblePhytoplanktonDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryPhytoplanktonDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryTotal NitrogenDetails
RNAGDiffuse sourceOther (not in list, must add details in comments)Agriculture and rural land managementTotal NitrogenDetails
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
RFDPoint sourceSewage discharge (continuous)Water IndustryTotal PhosphorusDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryTotal PhosphorusDetails

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 Industry0300000
Local & central government0000000
Domestic general public0000000
Recreation0000000
Waste treatment and disposal0000000
Other0000000
No sector responsible0000000
Sector under investigation0000000
Total0300010

Objectives

Classification ItemStatusYearReasons
EcologicalGood2060Disproportionately expensive: Disproportionate burdens;
Natural conditions: Ecological recovery time
Biological quality elementsGood2060Disproportionately expensive: Disproportionate burdens;
Natural conditions: Ecological recovery time
Macrophytes and Phytobenthos CombinedNot assessed2015Disproportionately expensive: Disproportionate burdens
PhytoplanktonGood2060Disproportionately expensive: Disproportionate burdens;
Natural conditions: Ecological recovery time
Physico-chemical quality elementsGood2060Disproportionately expensive: Disproportionate burdens;
Natural conditions: Ecological recovery time
SalinityGood2015
Total NitrogenGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Total PhosphorusGood2060Disproportionately expensive: Disproportionate burdens;
Natural conditions: Ecological recovery time
Hydromorphological Supporting ElementsSupports good2015
Hydrological RegimeSupports good2015
Supporting elements (Surface Water)Good2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Expert JudgementGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Mitigation Measures AssessmentGood2015
Specific pollutantsHigh2015
CopperHigh2015
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(a)pyreneGood2015
Dioxins and dioxin-like compoundsGood2015
Heptachlor and cis-Heptachlor epoxideGood2015
Hexabromocyclododecane (HBCDD)Good2015
HexachlorobenzeneGood2015
HexachlorobutadieneGood2015
Mercury and Its CompoundsGood2015
Perfluorooctane sulphonate (PFOS)Good2039Technically infeasible: No known technical solution is available
Polybrominated diphenyl ethers (PBDE)Good2063Natural conditions: Chemical status recovery time
Priority substancesGood2015
FluorantheneGood2015
Other PollutantsDoes not require assessment2015

Protected areas

PA NameIdDirectiveMore information
Great Ouse NVZS391Nitrates Directive
Huntingdon River GravelsG144Nitrates Directive
Stewartby LakeUKENLK158Urban 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
162062 1620622014, 2012, 2009, 20132019, 2014, 2013, 2016, 20152019
ELSTOW BK.OUTFLOW STEWARTBY LAKE 12M1220092015, 2016
STEWARTBY LAKE CONCRETE PLATFORM 12M432009, 2014, 20122019, 2016, 2014, 20152019, 2022
146143 1461432016, 20192019, 2022

Upstream water bodies

    Downstream water bodies