Pix Brook Water Body

Moderate ecological status

Attributes

  • Water Body IDGB105033037730
  • Water Body TypeRiver
  • Hydromorphological designationheavily modified
  • NGRTL2122536065
  • Surveillance Water BodyNo
  • Length7.931 km
  • Catchment area15.505 km2
  • Catchment area1550.51 ha

Classifications

Classification Item20192022
EcologicalModerateModerate
Biological quality elementsModerateModerate
InvertebratesModerateModerate
Macrophytes and Phytobenthos Combined
Macrophytes Sub ElementBadBad
Physico-chemical quality elementsModerateModerate
Acid Neutralising CapacityHighHigh
Ammonia (Phys-Chem)GoodGood
Biochemical Oxygen Demand (BOD)High
Dissolved oxygenHighHigh
PhosphatePoorPoor
TemperatureHighHigh
pHHighHigh
Hydromorphological Supporting ElementsSupports goodSupports good
Hydrological RegimeSupports goodSupports good
Supporting elements (Surface Water)GoodGood
Mitigation Measures AssessmentGoodGood
Specific pollutantsHighHigh
CopperHighHigh
IronHighHigh
ManganeseHighHigh
PermethrinHighHigh
TriclosanHighHigh
ZincHighHigh
ChemicalFailDoes not require assessment
Priority hazardous substancesFailDoes not require assessment
Benzo(a)pyreneGood
Benzo(b)fluorantheneGood
Benzo(g-h-i)peryleneGood
Benzo(k)fluorantheneGood
Cadmium and Its CompoundsGood
Di(2-ethylhexyl)phthalate (Priority hazardous)Good
Dioxins and dioxin-like compoundsGood
Heptachlor and cis-Heptachlor epoxideGood
Hexabromocyclododecane (HBCDD)Good
HexachlorobenzeneGood
HexachlorobutadieneGood
Mercury and Its CompoundsGood
NonylphenolGood
Perfluorooctane sulphonate (PFOS)Fail
Polybrominated diphenyl ethers (PBDE)Fail
Priority substancesFailDoes not require assessment
Cypermethrin (Priority)Good
FluorantheneGood
Lead and Its CompoundsGood
Nickel and Its CompoundsFail
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
Phosphate22014PoorVery certain there is a problem
Ammonia (Phys-Chem)22013PoorVery 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
RNAGDiffuse sourceOther (not in list, must add details in comments)Urban and transportPhosphateDetails
RNAGPoint sourceSewage discharge (intermittent)Water IndustryPhosphateDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryPhosphateDetails
RNAGUnknown (pending investigation)Unknown (pending investigation)Sector under investigationPerfluorooctane sulphonate (PFOS)Details
RFDUnknown (pending investigation)Unknown (pending investigation)Sector under investigationNickel and Its CompoundsDetails
RNAGmeasures delivered to address reason, awaiting recoveryNot applicableNo sector responsiblePolybrominated diphenyl ethers (PBDE)Details

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 transport0010000
Water Industry0200000
Local & central government0000000
Domestic general public0000000
Recreation0000000
Waste treatment and disposal0000000
Other0000000
No sector responsible0000000
Sector under investigation0000000
Total0210000

Objectives

Classification ItemStatusYearReasons
EcologicalModerate2015Disproportionately expensive: Disproportionate burdens;
Technically infeasible: No known technical solution is available
Biological quality elementsGood2015
InvertebratesGood2015
Macrophytes and Phytobenthos CombinedNot assessed2015Technically infeasible: No known technical solution is available
Physico-chemical quality elementsModerate2015Disproportionately expensive: Disproportionate burdens;
Technically infeasible: No known technical solution is available
Acid Neutralising CapacityGood2015
Ammonia (Phys-Chem)Good2021Disproportionately expensive: Disproportionate burdens
Dissolved oxygenGood2015
PhosphatePoor2015Technically infeasible: No known technical solution is available
TemperatureGood2015
pHGood2015
Hydromorphological Supporting ElementsSupports good2015
Hydrological RegimeSupports good2015
Supporting elements (Surface Water)Good2015
Mitigation Measures AssessmentGood2015
Specific pollutantsHigh2015
CopperHigh2015
IronHigh2015
ManganeseHigh2015
PermethrinHigh2015
TriclosanHigh2015
ZincHigh2015
ChemicalGood2063Disproportionately expensive: Disproportionate burdens;
Natural conditions: Chemical status recovery time;
Technically infeasible: No known technical solution is available
Priority hazardous substancesGood2063Disproportionately expensive: Disproportionate burdens;
Natural conditions: Chemical status recovery time;
Technically infeasible: No known technical solution is available
Benzo (b) and (k) fluorantheneGood2015
Benzo (ghi) perelyene and indeno (123-cd) pyreneGood2015
Benzo(a)pyreneGood2015
Benzo(b)fluorantheneGood2015
Benzo(g-h-i)peryleneGood2015
Benzo(k)fluorantheneGood2015
Cadmium and Its CompoundsGood2015
Di(2-ethylhexyl)phthalate (Priority hazardous)Good2021Disproportionately expensive: Disproportionate burdens
Dioxins and dioxin-like compoundsGood2015
Heptachlor and cis-Heptachlor epoxideGood2015
Hexabromocyclododecane (HBCDD)Good2015
HexachlorobenzeneGood2015
HexachlorobutadieneGood2015
Mercury and Its CompoundsGood2015
NonylphenolGood2015
Perfluorooctane sulphonate (PFOS)Good2039Technically infeasible: No known technical solution is available
Polybrominated diphenyl ethers (PBDE)Good2063Natural conditions: Chemical status recovery time
Priority substancesGood2015
Cypermethrin (Priority)Good2015
FluorantheneGood2015
Lead and Its CompoundsGood2015
Nickel and Its CompoundsGood2015
Other PollutantsDoes not require assessment2015

Protected areas

PA NameIdDirectiveMore information
Great Ouse NVZS391Nitrates Directive
Anglian ChalkG71Nitrates Directive
River IvelUKENRI75Urban 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
PIX BK.CHURCH END ARLESEY 14M072009, 2012, 2013, 2011, 2014, 20102016, 2019, 2015, 2013, 20142019, 2022
PIX BK.OUTLET RESERVOIR U/S LETCHWORTH 14M052009, 2012, 2013, 2011, 2014, 20102016, 2019, 2015, 2013, 20142019
PIX BK.COWSLIP HILL LETCHWORTH 14M152009, 2012, 2010, 2011
SIX FOOT STREAM COWSLIP HILL LETCHWORTH 14M162009, 2012, 2010, 2011
PIX BK. FT. BR. D/S OF LETCHWORTH STW 14M172015, 2016, 20192019
159644 1596442014, 20132014, 2013, 2016, 2015
56224 562242010, 2013, 2011, 2012, 20092015, 2013, 2016, 20192019
MIDDLE OUSE/PIX BROOK/CHURCH END ARLESEY/ 345592013, 2011, 2014, 2012

Upstream water bodies

    Downstream water bodies