Solent Water Body

Moderate ecological status


  • Water Body IDGB650705150000
  • Water Body TypeCoastal Water
  • Hydromorphological designationheavily modified
  • NGRSZ6253694364
  • Surveillance Water BodyYes
  • Surface area25993.588 ha
  • Surface area259.936 km2


Classification Item20192022
Biological quality elementsModerateModerate
Infaunal Quality IndexHighHigh
Opportunistic MacroalgaeGoodGood
Physico-chemical quality elementsModerateModerate
Dissolved Inorganic NitrogenModerateModerate
Dissolved oxygenHighHigh
Supporting elements (Surface Water)GoodGood
Mitigation Measures AssessmentGoodGood
Specific pollutantsHighHigh
Chromium (VI)HighHigh
Un-ionised ammoniaHighHigh
ChemicalFailDoes not require assessment
Priority hazardous substancesFailDoes not require assessment
Cadmium and Its CompoundsGood
Dioxins and dioxin-like compoundsGood
Heptachlor and cis-Heptachlor epoxideGood
Hexabromocyclododecane (HBCDD)Good
Mercury and Its CompoundsFail
Perfluorooctane sulphonate (PFOS)Good
Polybrominated diphenyl ethers (PBDE)Fail
Tributyltin CompoundsGood
Priority substancesGoodDoes not require assessment
Lead and Its CompoundsGood
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

Classification ElementCycleYearStatusOutcome
Dissolved Inorganic Nitrogen22015ModerateCertain there is not 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
RNAGPhysical modificationFlood protection - structuresSector under investigationAngiospermsDetails
RNAGPhysical modificationOther (not in list, must add details in comments)Sector under investigationMitigation Measures AssessmentDetails
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 management0000000
Mining and quarrying0000000
Urban and transport0000000
Water Industry0000000
Local & central government0000000
Domestic general public0000000
Waste treatment and disposal0000000
No sector responsible0000000
Sector under investigation1000000


Classification ItemStatusYearReasons
EcologicalModerate2015Disproportionately expensive: Disproportionate burdens;
Disproportionately expensive: Unfavourable balance of costs and benefits;
Good status prevented by A/HMWB designated use: Action to get biological element to good would have significant adverse impact on use
Biological quality elementsModerate2021Good status prevented by A/HMWB designated use: Action to get biological element to good would have significant adverse impact on use
AngiospermsModerate2021Good status prevented by A/HMWB designated use: Action to get biological element to good would have significant adverse impact on use
Physico-chemical quality elementsModerate2015Disproportionately expensive: Unfavourable balance of costs and benefits
Dissolved Inorganic NitrogenModerate2021Disproportionately expensive: Unfavourable balance of costs and benefits
Dissolved oxygenGood2015
Hydromorphological Supporting ElementsNot assessed2015
Supporting elements (Surface Water)Good2021Disproportionately expensive: Disproportionate burdens
Mitigation Measures AssessmentGood2021Disproportionately expensive: Disproportionate burdens
Specific pollutantsHigh2015
Chromium (VI)High2015
Un-ionised ammoniaHigh2015
ChemicalGood2063Disproportionately expensive: Disproportionate burdens;
Natural conditions: Chemical status recovery time
Priority hazardous substancesGood2063Disproportionately expensive: Disproportionate burdens;
Natural conditions: Chemical status recovery time
Cadmium and Its CompoundsGood2015
Dioxins and dioxin-like compoundsGood2015
Heptachlor and cis-Heptachlor epoxideGood2021Natural conditions: Chemical status recovery time
Hexabromocyclododecane (HBCDD)Good2015
Mercury and Its CompoundsGood2040Natural conditions: Chemical status recovery time
Perfluorooctane sulphonate (PFOS)Good2015
Polybrominated diphenyl ethers (PBDE)Good2063Natural conditions: Chemical status recovery time
Tributyltin CompoundsGood2021Disproportionately expensive: Disproportionate burdens
Priority substancesGood2015
Lead and Its CompoundsGood2015
Nickel and Its CompoundsGood2015
Other PollutantsDoes not require assessment2015

Protected areas

PA NameIdDirectiveMore information
Hamble Estuary Eutrophic NVZ (TraC)ET3Nitrates Directive
Chichester HarbourUKENCA56Urban Waste Water Treatment Directive
Cowes and Medina_MUKSW45Shellfish Water Directive
EastneyUK16500Bathing Water Directive
Lymington and Sowley_MUKSW40Shellfish Water Directive
Chichester,Langstone and Portsmouth Harbours Eutrophic NVZ (TraC)ET2Nitrates Directive
Chichester And Langstone HarboursUK9011011Special Protection AreaNatural England
Solent MaritimeUK0030059Special Area of ConservationNatural England
Chichester And Langstone HarboursUK11013Ramsar SiteNatural England
Approaches to Southampton WaterUKSW36Shellfish Water Directive
Solent And Dorset CoastUK9020330Special Protection AreaNatural England
South Wight MaritimeUK0030061Special Area of ConservationNatural England
Solent & Southampton WaterUK9011061Special Protection AreaNatural England
Solent & Southampton WaterUK11063Ramsar SiteNatural England
Solent & Isle Of Wight LagoonsUK0017073Special Area of ConservationNatural England
PenningtonUKSW41Shellfish Water Directive
Langstone HarbourUKSW33Shellfish Water Directive
RydeUK17900Bathing Water Directive
YarmouthUKSW42Shellfish Water Directive
Newtown harbour, Mediina Estuary and Eastern Yar Eutrophic NVZ (TraC)ET7Nitrates Directive
Stokes BayUK16700Bathing Water Directive
Lepe Middle BankUKSW38Shellfish Water Directive
Central SolentUKSW46Shellfish Water Directive
East CowesUK17850Bathing Water Directive
Stanswood BayUKSW37Shellfish Water Directive
CalshotUK16900Bathing Water Directive
Medina EstuaryUKENCA121Urban Waste Water Treatment Directive
Newtown_MUKSW43Shellfish Water Directive
Newtown HarbourUKENCA124Urban Waste Water Treatment Directive
Colwell BayUK17600Bathing Water Directive
RydeUKSW47Shellfish Water Directive
Beachlands WestUK16400Bathing Water Directive
EastokeUK16300Bathing Water Directive
LepeUK17000Bathing Water Directive
Lee-on-SolentUK16800Bathing Water Directive
SeagroveUK18000Bathing Water Directive
HillheadUK16850Bathing Water Directive
Beachlands CentralUK16350Bathing Water Directive
Spithead and Stokes BayUKSW48Shellfish Water Directive
CowesUK17800Bathing Water Directive
Totland BayUK17500Bathing Water Directive
GurnardUK17700Bathing Water Directive
Southsea EastUK16600Bathing Water 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
RYDE-SHELLFISH WATER Y00174772011, 2010, 2013, 20122016, 2019, 20152019
NR EASTNEY LONG SEA OUTFALL G00168732011, 2010, 2013, 2009, 2012
NEWTOWN BANK-SHELLFISH WATER Y00174752011, 2010, 2013, 20122016, 2019, 20152019
TOTLAND-SHELLFISH WATER Y00044062011, 2010, 2013, 20122015
SPITHEAD AND STOKES BAY-SFW G00037212011, 2010, 2013, 20122015
EAST BRAMBLES SAMPLING POINT G00035322013, 2009, 2011, 2010, 20122016, 2019, 20152019
LEPE MIDDLE BANK-SFW G00037652011, 2010, 2013, 20122015
LYMINGTON-SHELLFISH WATER G00036962011, 2010, 2013, 20122015
SOWLEY-SHELLFISH WATER G00039952011, 2010, 2012
COWES-SHELLFISH WATER Y00043672011, 2010, 2013, 20122015
CALSHOT/STANSWOOD-SFW G00036812011, 2010, 2013, 20122015
PENNINGTON-SHELLFISH WATER G00037512011, 2010, 2013, 20122016, 2019, 20152019
D/S PEEL COMMON EMZ G00034952011, 2010, 2013, 2009, 2012
YARMOUTH-SHELLFISH WATER Y00174742011, 2010, 2013, 20122015
D/S PENNINGTON SO EMZ G00060112011, 2009, 2010, 2013, 20122015, 2016, 20192019
MOTHER BANK/OSBORNE BAY Y000427820132016, 2019, 20152019
CENTRAL SOLENT-SHELLFISH WATER G00037152011, 2010, 2013, 20122015

Downstream water bodies