Bolam Lake Water Body

Moderate ecological status

Attributes

  • Water Body IDGB30327908
  • Water Body TypeLake
  • Hydromorphological designationheavily modified
  • NGRNZ0820581831
  • Surveillance Water BodyNo
  • Surface area9.739 ha
  • Altitude127 m
  • Mean depth0.571 m
  • Surface area0.097 km2
  • Catchment area84.5 ha

Classifications

Classification Item20192022
EcologicalModerateModerate
Biological quality elementsHighHigh
PhytoplanktonHighHigh
Physico-chemical quality elementsModerateModerate
SalinityHighHigh
Total NitrogenModeratePoor
Total PhosphorusModerateModerate
Hydromorphological Supporting ElementsSupports goodSupports good
Hydrological RegimeHighHigh
Supporting elements (Surface Water)ModerateModerate
Expert JudgementModerateModerate
Mitigation Measures AssessmentGoodGood
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
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 responsibleMercury and Its CompoundsDetails
RNAGUnknown (pending investigation)Unknown (pending investigation)Sector under investigationTotal NitrogenDetails
RNAGmeasures delivered to address reason, awaiting recoveryNot applicableNo sector responsiblePolybrominated diphenyl ethers (PBDE)Details
RNAGUnknown (pending investigation)Unknown (pending investigation)Sector under investigationTotal PhosphorusDetails
RNAGDiffuse sourcePoor nutrient managementAgriculture and rural land managementTotal PhosphorusDetails
RNAGPoint sourcePrivate Sewage TreatmentDomestic General PublicTotal 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 management0000000
Industry0000000
Mining and quarrying0000000
Navigation0000000
Urban and transport0000000
Water Industry0000000
Local & central government0000000
Domestic general public0000000
Recreation0000000
Waste treatment and disposal0000000
Other0000000
No sector responsible0000000
Sector under investigation0000000
Total0000000

Objectives

Classification ItemStatusYearReasons
EcologicalGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Biological quality elementsGood2021Disproportionately expensive: Disproportionate burdens
PhytoplanktonGood2021Disproportionately expensive: Disproportionate burdens
Physico-chemical quality elementsGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
SalinityGood2015
Total NitrogenGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Total PhosphorusGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
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 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
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
BOLAM LAKE AT OUTLET 426002932013, 2014, 20122019, 2013, 2016, 2014, 20152019, 2022

Upstream water bodies

    Downstream water bodies