Wensum DS Norwich Water Body

Moderate ecological status

Attributes

  • Water Body IDGB105034055882
  • Water Body TypeRiver
  • Hydromorphological designationheavily modified
  • NGRTG2265708980
  • Length8.936 km
  • Surveillance Water BodyNo
  • Catchment area32.498 km2
  • Catchment area3249.784 ha

Classifications

Classification Item20192022
EcologicalModerateModerate
Biological quality elementsGoodGood
FishHighGood
InvertebratesHighHigh
Macrophytes and Phytobenthos CombinedGoodGood
Macrophytes Sub ElementGoodGood
Physico-chemical quality elementsGoodGood
Acid Neutralising CapacityHighHigh
Ammonia (Phys-Chem)HighHigh
Dissolved oxygenHighHigh
PhosphateGoodGood
TemperatureHighHigh
pHHighHigh
Hydromorphological Supporting ElementsSupports goodSupports good
Hydrological RegimeDoes not support goodDoes not support good
Supporting elements (Surface Water)ModerateModerate
Mitigation Measures AssessmentModerate or lessModerate or less
Specific pollutantsHighHigh
2,4-dichlorophenoxyacetic acidHighHigh
ArsenicHighHigh
CarbendazimHighHigh
ChlorothalonilHighHigh
CopperHighHigh
DiazinonHighHigh
DimethoateHighHigh
GlyphosateHighHigh
IronHighHigh
LinuronHighHigh
ManganeseHighHigh
MecopropHighHigh
PendimethalinHighHigh
PermethrinHighHigh
ZincHighHigh
ChemicalFailDoes not require assessment
Priority hazardous substancesFailDoes not require assessment
Benzo(a)pyreneGood
Cadmium and Its CompoundsGood
Dioxins and dioxin-like compoundsGood
Heptachlor and cis-Heptachlor epoxideGood
Hexabromocyclododecane (HBCDD)Good
HexachlorobenzeneGood
HexachlorobutadieneGood
HexachlorocyclohexaneGood
Mercury and Its CompoundsGood
PentachlorobenzeneGood
Perfluorooctane sulphonate (PFOS)Good
Polybrominated diphenyl ethers (PBDE)Fail
QuinoxyfenGood
Tributyltin CompoundsGood
Trifluralin (Priority hazardous)Good
Priority substancesGoodDoes not require assessment
1,2-dichloroethaneGood
AclonifenGood
AlachlorGood
AtrazineGood
BifenoxGood
ChlorfenvinphosGood
ChlorpyrifosGood
CybutryneGood
Cypermethrin (Priority)Good
Dichlorvos (Priority)Good
DiuronGood
FluorantheneGood
IsoproturonGood
Lead and Its CompoundsGood
Nickel and Its CompoundsGood
PentachlorophenolGood
SimazineGood
TerbutrynGood
TrichloromethaneGood
Other PollutantsGoodDoes not require assessment
Aldrin, Dieldrin, Endrin & IsodrinGood
Carbon TetrachlorideGood
TetrachloroethyleneGood
TrichloroethyleneGood
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
RNAGDiffuse sourcePoor nutrient managementAgriculture and rural land managementMacrophytes and Phytobenthos CombinedDetails
RNAGDiffuse sourceUrbanisation - urban developmentUrban and transportMacrophytes and Phytobenthos CombinedDetails
RNAGmeasures delivered to address reason, awaiting recoveryNot applicableNo sector responsiblePolybrominated diphenyl ethers (PBDE)Details
RNAGFlowSurface water abstractionWater IndustryHydrological RegimeDetails
RNAGPhysical modificationOther (not in list, must add details in comments)RecreationMitigation Measures AssessmentDetails
RNAGPoint sourceSewage discharge (intermittent)Water IndustryMacrophytes and Phytobenthos CombinedDetails
RNAGPhysical modificationOther (not in list, must add details in comments)NavigationMitigation Measures AssessmentDetails
RNAGPoint sourceSewage discharge (continuous)Water IndustryMacrophytes and Phytobenthos CombinedDetails

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 Industry0000000
Local & central government1000000
Domestic general public0000000
Recreation1000000
Waste treatment and disposal0000000
Other0000000
No sector responsible0000000
Sector under investigation0000000
Total3000000

Objectives

Classification ItemStatusYearReasons
EcologicalGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Biological quality elementsGood2021Disproportionately expensive: Disproportionate burdens
FishGood2015
InvertebratesGood2015
Macrophytes and Phytobenthos CombinedGood2021Disproportionately expensive: Disproportionate burdens
Physico-chemical quality elementsGood2015
Acid Neutralising CapacityGood2015
Ammonia (Phys-Chem)Good2015
Dissolved oxygenGood2015
PhosphateGood2015
TemperatureGood2015
pHGood2015
Hydromorphological Supporting ElementsSupports good2015
Hydrological RegimeDoes not support good2015Disproportionately expensive: Unfavourable balance of costs and benefits
Supporting elements (Surface Water)Good2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Mitigation Measures AssessmentGood2027 - Low confidenceDisproportionately expensive: Disproportionate burdens
Specific pollutantsHigh2015
2,4-dichlorophenoxyacetic acidHigh2015
ArsenicHigh2015
CarbendazimHigh2015
ChlorothalonilHigh2015
CopperHigh2015
DiazinonHigh2015
DimethoateHigh2015
GlyphosateHigh2015
IronHigh2015
LinuronHigh2015
ManganeseHigh2015
MecopropHigh2015
PendimethalinHigh2015
PermethrinHigh2015
ZincHigh2015
ChemicalGood2063Natural conditions: Chemical status recovery time
Priority hazardous substancesGood2063Natural conditions: Chemical status recovery time
Benzo (b) and (k) fluorantheneGood2015
Benzo (ghi) perelyene and indeno (123-cd) pyreneGood2015
Benzo(a)pyreneGood2015
Cadmium and Its CompoundsGood2015
Dioxins and dioxin-like compoundsGood2015
EndosulfanGood2015
Heptachlor and cis-Heptachlor epoxideGood2015
Hexabromocyclododecane (HBCDD)Good2015
HexachlorobenzeneGood2015
HexachlorobutadieneGood2015
HexachlorocyclohexaneGood2015
Mercury and Its CompoundsGood2015
PentachlorobenzeneGood2015
Perfluorooctane sulphonate (PFOS)Good2015
Polybrominated diphenyl ethers (PBDE)Good2063Natural conditions: Chemical status recovery time
QuinoxyfenGood2015
Tributyltin CompoundsGood2015
Trifluralin (Priority hazardous)Good2015
Priority substancesGood2015
1,2-dichloroethaneGood2015
AclonifenGood2015
AlachlorGood2015
AtrazineGood2015
BifenoxGood2015
ChlorfenvinphosGood2015
ChlorpyrifosGood2015
CybutryneGood2015
Cypermethrin (Priority)Good2015
Dichlorvos (Priority)Good2015
DiuronGood2015
FluorantheneGood2015
IsoproturonGood2015
Lead and Its CompoundsGood2015
Nickel and Its CompoundsGood2015
PentachlorophenolGood2015
SimazineGood2015
TerbutrynGood2015
TrichloromethaneGood2015
Other PollutantsGood2015
Aldrin, Dieldrin, Endrin & IsodrinGood2015
Carbon TetrachlorideGood2015
TetrachloroethyleneGood2015
TrichloroethyleneGood2015
para - para DDTGood2015

Protected areas

PA NameIdDirectiveMore information
Norwich Crag and GravelsG79Nitrates Directive
River Wensum (SWSGZ1016 & SWSGZ1017)SWSGZ1016Safeguard Zone
River WensumUKENRI73Urban Waste Water Treatment Directive
Wensum DS NorwichUKGB105034055882Drinking 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
146785 1467852013, 2011, 20142016, 2015, 2019, 2014, 20132019
300M D/S HELLESDON BRIDGE (14) WEN242A20192019
R.WENSUM CARROW BRIDGE NORWICH WEN2802010, 2013, 2011, 2014, 2009, 20122013, 2014, 2019, 2016, 20152019, 2022
R.WENSUM NEW MILLS WEN2602010, 2013, 2011, 2014, 2009, 201220192022, 2019
155759 1557592013, 2011, 20142016, 2015, 2019, 2014, 20132019
54967 549672009, 2011, 2014, 20102016, 2014, 2015
WENSUM CATCHMENT/WENSUM/WENSUM (CENTRAL)/HELLESDON ROAD (ALBERT'S)/ 15032013, 2011, 2014, 2012, 20102013, 2016, 2014, 2019, 20152022, 2019
R.WENSUM HEIGHAM INTAKE WEN2522013, 20092015
R.WENSUM HELLESDON MILL WEN2402013, 2010, 2011, 2014, 2009, 2012
R.WENSUM SWEET BRIAR RD.BR WEN2502012, 2013, 2010, 2011, 2014, 20092015, 2016, 2013, 2019, 20142019, 2022
155176 1551762013, 2011, 2014
54966 549662009, 2014, 2012, 2010, 20132016, 2019, 2014, 2015, 20132019
RIVER WENSUM TROWSE SWING BRIDGE WEN2852011, 2012, 2010, 20132016, 20192019

Upstream water bodies

Downstream water bodies