Grendon Brook Water Body

Moderate ecological status

Attributes

  • Water Body IDGB105032045330
  • Water Body TypeRiver
  • Hydromorphological designationnot designated artificial or heavily modified
  • NGRSP8778262767
  • Catchment area1783.71 ha
  • Length4.388 km
  • Catchment area17.837 km2
  • Surveillance Water BodyNo

Classifications

Classification Item20192022
EcologicalModerateModerate
Biological quality elementsGoodGood
InvertebratesGoodGood
Physico-chemical quality elementsModerateModerate
Ammonia (Phys-Chem)HighHigh
Dissolved oxygenHighHigh
PhosphatePoorPoor
TemperatureHighHigh
pHHighHigh
Hydromorphological Supporting ElementsSupports goodSupports good
Hydrological RegimeSupports 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)Fail
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
RNAGDiffuse sourcePoor nutrient managementAgriculture and rural land managementPhosphateDetails
RNAGDiffuse sourcePoor Livestock ManagementAgriculture and rural land managementPhosphateDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryPhosphateDetails
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
RNAGmeasures delivered to address reason, awaiting recoveryNot applicableNo sector responsibleMercury and Its CompoundsDetails

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 management0000020
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
Total0100020

Objectives

Classification ItemStatusYearReasons
EcologicalPoor2015Disproportionately expensive: Unfavourable balance of costs and benefits
Biological quality elementsPoor2015Disproportionately expensive: Unfavourable balance of costs and benefits
InvertebratesGood2015
Macrophytes and Phytobenthos CombinedPoor2015Disproportionately expensive: Unfavourable balance of costs and benefits
Physico-chemical quality elementsModerate2015Disproportionately expensive: Unfavourable balance of costs and benefits
Ammonia (Phys-Chem)Good2015
Dissolved oxygenGood2015
PhosphatePoor2015Disproportionately expensive: Unfavourable balance of costs and benefits
TemperatureGood2015
pHGood2015
Hydromorphological Supporting ElementsSupports good2015
Hydrological RegimeSupports good2015
Supporting elements (Surface Water)Not assessed2015
Specific pollutantsNot assessed2015
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 CompoundsGood2040Natural conditions: Chemical status recovery time
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
Other PollutantsDoes not require assessment2015

Protected areas

PA NameIdDirectiveMore information
Thrapstone lake Eutrophic lake NVZEL148Nitrates Directive
River Nene NVZS382Nitrates Directive
Northampton SandsG165Nitrates Directive
Upper Nene Valley Gravel PitsUK9020296Special Protection AreaNatural England
Upper Nene Valley Gravel PitsUK11083Ramsar SiteNatural England

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
GRENDON BK.RYEHOLMES BRIDGE GREN050R2014, 2012, 20132014, 2015, 2013, 2016, 20192019
55574 5557420142015, 2016, 2019, 20142019
R.NENE WELLINGBOROUGH RD.BR. NENE240W2010, 2009
R.NENE BILLING RD.BR. NENE170B2010, 2009
R.NENE WHITE MILLS NENE200W2010, 2009
R.NENE NUNN MILLS RD.BR. NENE110N2010, 2009
R.NENE HARDWATER MILL NENE220H2010, 2009
160241 1602412015, 2014, 2013, 2016