Silchester Brook Water Body

Moderate ecological status

Attributes

  • Water Body IDGB106039017190
  • Water Body TypeRiver
  • Hydromorphological designationnot designated artificial or heavily modified
  • NGRSU6259360785
  • Catchment area23.155 km2
  • Surveillance Water BodyNo
  • Length11.06 km
  • Catchment area2315.53 ha

Classifications

Classification Item20192022
EcologicalModerateModerate
Biological quality elementsModerateModerate
InvertebratesGoodGood
Macrophytes and Phytobenthos CombinedModerateModerate
Macrophytes Sub ElementModerateModerate
Phytobenthos Sub ElementModerateModerate
Physico-chemical quality elementsModerateModerate
Acid Neutralising CapacityHighHigh
Ammonia (Phys-Chem)GoodGood
Dissolved oxygenModerateGood
PhosphatePoorPoor
TemperatureHighHigh
pHHighHigh
Hydromorphological Supporting ElementsSupports goodSupports good
Hydrological RegimeSupports goodSupports good
MorphologySupports goodSupports good
Specific pollutantsHighHigh
CopperHighHigh
ChemicalFailDoes not require assessment
Priority hazardous substancesFailDoes not require assessment
Benzo(a)pyreneGood
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 substancesGoodDoes not require assessment
Cypermethrin (Priority)Good
FluorantheneGood
Nickel and Its CompoundsGood
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
RNAGMethod Change (RFD Only)Not applicableNo sector responsibleDissolved oxygenDetails
RFDHigh to Good deterioration, no action required (RFD only)Not applicableNo sector responsibleAmmonia (Phys-Chem)Details
RNAGPoint sourcePrivate Sewage TreatmentNo sector responsibleDissolved oxygenDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryMacrophytes and Phytobenthos CombinedDetails
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
RNAGPoint sourceSewage discharge (intermittent)Sector under investigationDissolved oxygenDetails
RNAGPoint sourceSewage discharge (intermittent)Sector under investigationPhosphateDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryDissolved oxygenDetails
RNAGSuspect dataNot applicableNo sector responsiblePhosphateDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryPhosphateDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryPhosphateDetails

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 Industry0300000
Local & central government0000000
Domestic general public0000000
Recreation0000000
Waste treatment and disposal0000000
Other0000000
No sector responsible0000000
Sector under investigation0000000
Total0300000

Objectives

Classification ItemStatusYearReasons
EcologicalModerate2015Disproportionately expensive: Disproportionate burdens;
Technically infeasible: No known technical solution is available
Biological quality elementsModerate2015Disproportionately expensive: Disproportionate burdens;
Technically infeasible: No known technical solution is available
InvertebratesGood2021Disproportionately expensive: Disproportionate burdens
Macrophytes and Phytobenthos CombinedModerate2015Technically infeasible: No known technical solution is available
Physico-chemical quality elementsModerate2015Technically infeasible: No known technical solution is available
Acid Neutralising CapacityGood2015
Ammonia (Phys-Chem)Good2015
Dissolved oxygenGood2015
PhosphatePoor2015Technically infeasible: No known technical solution is available
TemperatureGood2015
pHGood2015
Hydromorphological Supporting ElementsSupports good2015
Hydrological RegimeSupports good2015
Supporting elements (Surface Water)Not assessed2015
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 (b) and (k) fluorantheneGood2015
Benzo (ghi) perelyene and indeno (123-cd) pyreneGood2015
Benzo(a)pyreneGood2015
Cadmium and Its CompoundsGood2015
Di(2-ethylhexyl)phthalate (Priority hazardous)Good2015
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
Nickel and Its CompoundsGood2015
Other PollutantsDoes not require assessment2015

Protected areas

PA NameIdDirectiveMore information
Lower Thames (Cookham Egham Teddington)SWSGZ4016Safeguard Zone
Foudry Brook (West End Brook to M4) NVZS459Nitrates Directive
River Kennet and Holy BrookSWSGZ4005Safeguard Zone

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
35936 359362014, 2010, 20092014, 2015, 2016
SILCHESTER BROOK BELOW SILCHESTER STW PKER00832009, 2014, 2013, 2011, 2012, 20102015, 2014, 2013, 2016
SILCHESTER BROOK ABOVE SILCHESTER STW PKER00812014, 2010, 2013, 2011, 2012, 20092014, 2013, 2015, 20162022
SILCHESTER BROOK AT CLAPPERS FARM, SILCH PKER00822014, 2010, 2013, 2011, 2012, 20092014, 2013, 2015, 2019, 20162022, 2019
THAMES/RIVER KENNET/FOUDRY BROOK/SILCHESTER BROOK/D/S SILCHESTER STW/ 381072013
THAMES/RIVER KENNET/FOUDRY BROOK/SILCHESTER BROOK/D/S CLAPPERS FARM/ 381082013
36127 361272011, 2012, 2013, 2009, 20102016, 2015, 2013
35935 359352014, 2010, 20092014, 2015, 2016
159701 1597012013, 20142016, 2015, 2014, 2013
159699 1596992016

Upstream water bodies