Thames (Cookham to Egham) Water Body

Moderate ecological status

Attributes

  • Water Body IDGB106039023231
  • Water Body TypeRiver
  • Hydromorphological designationheavily modified
  • NGRTQ0099272440
  • Catchment area65.884 km2
  • Surveillance Water BodyNo
  • Catchment area6588.353 ha
  • Length30.056 km

Classifications

Classification Item20192022
EcologicalModerateModerate
Biological quality elementsGoodGood
InvertebratesGoodGood
Macrophytes and Phytobenthos Combined
Macrophytes Sub ElementHighHigh
Physico-chemical quality elementsModerateModerate
Acid Neutralising CapacityHighHigh
Ammonia (Phys-Chem)HighHigh
Dissolved oxygenHighHigh
PhosphateModerateModerate
TemperatureHighHigh
pHHighHigh
Supporting elements (Surface Water)ModerateModerate
Mitigation Measures AssessmentModerate or lessModerate or less
Specific pollutantsHighHigh
ArsenicHighHigh
CopperHighHigh
IronHighHigh
ManganeseHighHigh
TolueneHighHigh
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
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
Tributyltin CompoundsGood
Trifluralin (Priority hazardous)Good
Priority substancesGoodDoes not require assessment
AtrazineGood
BenzeneGood
Cypermethrin (Priority)Good
FluorantheneGood
Lead and Its CompoundsGood
Nickel and Its CompoundsGood
SimazineGood
Other PollutantsGoodDoes not require assessment
Aldrin, Dieldrin, Endrin & IsodrinGood
para - para DDTGood

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
RNAGPhysical modificationOther (not in list, must add details in comments)Local and Central GovernmentMitigation Measures AssessmentDetails
RNAGPhysical modificationOther (not in list, must add details in comments)Water IndustryMitigation Measures AssessmentDetails
RNAGPhysical modificationOther (not in list, must add details in comments)NavigationMitigation Measures AssessmentDetails
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)Water IndustryPhosphateDetails
RNAGDiffuse sourceTransport DrainageUrban and transportPhosphateDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryPhosphateDetails
RNAGDiffuse sourcePoor nutrient managementAgriculture and rural land managementPhosphateDetails

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
Navigation1000000
Urban and transport0000000
Water Industry1000000
Local & central government1000000
Domestic general public0000000
Recreation0000000
Waste treatment and disposal0000000
Other0000000
No sector responsible0000000
Sector under investigation0000000
Total3000000

Objectives

Classification ItemStatusYearReasons
EcologicalModerate2015Technically infeasible: No known technical solution is available;
Technically infeasible: Practical technical constraints prevent implementation of the measure by an earlier deadline
Biological quality elementsGood2015
InvertebratesGood2015
Macrophytes and Phytobenthos CombinedNot assessed2015
Physico-chemical quality elementsModerate2015Technically infeasible: No known technical solution is available
Acid Neutralising CapacityGood2015
Ammonia (Phys-Chem)Good2015
Dissolved oxygenGood2015
PhosphateModerate2015Technically infeasible: No known technical solution is available
TemperatureGood2015
pHGood2015
Hydromorphological Supporting ElementsNot assessed2015
Supporting elements (Surface Water)Good2033Technically infeasible: Practical technical constraints prevent implementation of the measure by an earlier deadline
Mitigation Measures AssessmentGood2033Technically infeasible: Practical technical constraints prevent implementation of the measure by an earlier deadline
Specific pollutantsHigh2015
ArsenicHigh2015
CopperHigh2015
IronHigh2015
ManganeseHigh2015
TolueneHigh2015
ZincHigh2015
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
Benzo(b)fluorantheneGood2015
Benzo(g-h-i)peryleneGood2015
Benzo(k)fluorantheneGood2015
Cadmium and Its CompoundsGood2015
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
Tributyltin CompoundsGood2015
Trifluralin (Priority hazardous)Good2015
Priority substancesGood2015
AtrazineGood2015
BenzeneGood2015
Cypermethrin (Priority)Good2015
FluorantheneGood2015
Lead and Its CompoundsGood2015
Nickel and Its CompoundsGood2015
SimazineGood2015
Other PollutantsGood2015
Aldrin, Dieldrin, Endrin & IsodrinGood2015
para - para DDTGood2015

Protected areas

PA NameIdDirectiveMore information
Lower Thames (Cookham Egham Teddington)SWSGZ4016Safeguard Zone
South West London WaterbodiesUK9012171Special Protection AreaNatural England
South West London WaterbodiesUK11065Ramsar SiteNatural England
Roundmoor Ditch and Boveney Ditch NVZS466Nitrates Directive
River ThamesUKENRI17Urban Waste Water Treatment Directive
Thames (Cookham to Egham)UKGB106039023231Drinking Water Protected Area

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
THAMES AT SUNNYMEADS WATER INTAKE, WRAYS PTHR01082011, 2014, 2013, 2012, 2010, 2009
MYRKE DITCH ABOVE THAMES PTHR00452014, 2012, 2013, 2009
JUBILEE RIVER/TAPLOW/ 72922009
142689 1426892013, 2011
35603 356032010, 2013, 2011, 20142015, 2013, 2016, 2014
JUBILEE RIVER/ETON FAR SHORE/ 72892009
RIVER THAMES/THAMES JUVENILE SURVEY/BOULTERS WEIR STREAM/BOULTERS WEIR 3B/ 290242013
35907 359072010, 2013, 2011, 2009, 20142015, 2013, 2016, 2014
RIVER THAMES/THAMES TRIBS/BRAY MILL STREAM/ 222872009
RIVER THAMES/THAMES JUVENILE SURVEY/MONKEY ISLAND/MONKEY ISLAND 4A/ 290282013
RIVER THAMES/THAMES JUVENILE SURVEY/ETON COLLEGE/ETON 6B/ 290352013
THAMES ABOVE EGHAM NSWC PTHR00752012, 2011, 2014, 2009, 2013, 20102014, 2016, 2019, 2013, 20152019, 2022
RIVER THAMES/THAMES TRIBS/TANGIER MILL STREAM/ 350922013, 2011, 2012
35837 358372010
135341 1353412013, 2011
THAMES AT WINDSOR LEISURE CENTRE PTHR00652011, 2014, 2013, 2012, 20102014, 2013, 2015, 20162022
RIVER THAMES/THAMES JUVENILE SURVEY/OLD WINDSOR/OLD WINDSOR 7B/ 290382013
RIVER THAMES/THAMES JUVENILE SURVEY/OLD WINDSOR/OLD WINDSOR 7A/ 290372013
RIVER THAMES/CHALVEY DITCH/ 216662009
35862 358622013, 2011, 20122016, 2015, 2014, 2013
THAMES AT BOVENEY WEIR PTHR00792011, 2014, 2013, 2012, 2010, 200920192019

Downstream water bodies