MERSEY Water Body
Moderate ecological status
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Attributes
- Water Body IDGB531206908100
- Water Body TypeTransitional Water
- Hydromorphological designationheavily modified
- NGRSJ4588380424
- Surveillance Water BodyNo
- Surface area81.791 km2
- Surface area8179.061 ha
Classifications
| Classification Item | 2019 | 2022 |
|---|---|---|
| Ecological | Moderate | Moderate |
| Biological quality elements | Moderate | Moderate |
| Invertebrates | Moderate | Moderate |
| Infaunal Quality Index | Moderate | Moderate |
| Macroalgae | High | High |
| Opportunistic Macroalgae | High | High |
| Phytoplankton | Moderate | Moderate |
| Physico-chemical quality elements | Moderate | Moderate |
| Dissolved Inorganic Nitrogen | Moderate | Moderate |
| Dissolved oxygen | Good | Good |
| Hydromorphological Supporting Elements | Supports good | Supports good |
| Hydrological Regime | Supports good | Supports good |
| Supporting elements (Surface Water) | Moderate | Moderate |
| Mitigation Measures Assessment | Moderate or less | Moderate or less |
| Specific pollutants | Moderate | Moderate |
| 2,4-dichlorophenol | High | High |
| 2,4-dichlorophenoxyacetic acid | High | High |
| Arsenic | High | High |
| Chlorothalonil | High | High |
| Chromium (VI) | High | High |
| Copper | High | High |
| Diazinon | High | High |
| Dimethoate | High | High |
| Iron | High | High |
| Linuron | High | High |
| Mecoprop | High | High |
| Pendimethalin | High | High |
| Permethrin | High | High |
| Phenol | High | High |
| Toluene | High | High |
| Triclosan | High | High |
| Zinc | Moderate | Moderate |
| Chemical | Fail | Does not require assessment |
| Priority hazardous substances | Fail | Does not require assessment |
| Anthracene | Good | |
| Benzo(a)pyrene | Good | |
| Benzo(b)fluoranthene | Fail | |
| Benzo(g-h-i)perylene | Fail | |
| Benzo(k)fluoranthene | Good | |
| Cadmium and Its Compounds | Good | |
| Di(2-ethylhexyl)phthalate (Priority hazardous) | Good | |
| Dioxins and dioxin-like compounds | Good | |
| Endosulfan | Good | |
| Heptachlor and cis-Heptachlor epoxide | Fail | |
| Hexabromocyclododecane (HBCDD) | Good | |
| Hexachlorobenzene | Good | |
| Hexachlorobutadiene | Good | |
| Hexachlorocyclohexane | Good | |
| Mercury and Its Compounds | Fail | |
| Nonylphenol | Good | |
| Pentachlorobenzene | Good | |
| Perfluorooctane sulphonate (PFOS) | Good | |
| Polybrominated diphenyl ethers (PBDE) | Fail | |
| Quinoxyfen | Good | |
| Tributyltin Compounds | Good | |
| Trifluralin (Priority hazardous) | Good | |
| Priority substances | Fail | Does not require assessment |
| 1,2-dichloroethane | Good | |
| Aclonifen | Good | |
| Alachlor | Good | |
| Atrazine | Good | |
| Benzene | Good | |
| Bifenox | Good | |
| Chlorfenvinphos | Good | |
| Chlorpyrifos | Good | |
| Cybutryne | Good | |
| Dichloromethane | Good | |
| Dichlorvos (Priority) | Fail | |
| Diuron | Good | |
| Fluoranthene | Good | |
| Isoproturon | Good | |
| Lead and Its Compounds | Good | |
| Napthalene | Good | |
| Nickel and Its Compounds | Good | |
| Octylphenol | Good | |
| Pentachlorophenol | Good | |
| Simazine | Good | |
| Terbutryn | Good | |
| Trichlorobenzenes | Good | |
| Trichloromethane | Good | |
| Other Pollutants | Good | Does not require assessment |
| Aldrin, Dieldrin, Endrin & Isodrin | Good | |
| Carbon Tetrachloride | Good | |
| DDT Total | Good | |
| Tetrachloroethylene | Good | |
| Trichloroethylene | Good | |
| para - para DDT | Good |
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 Type | SWMI | Activity | Category | Classification Element | More information |
|---|---|---|---|---|---|
| RNAG | measures delivered to address reason, awaiting recovery | Not applicable | No sector responsible | Polybrominated diphenyl ethers (PBDE) | Details |
| RNAG | Diffuse source | Contaminated land | Industry | Zinc | Details |
| RNAG | Diffuse source | Contaminated water body bed sediments | Industry | Zinc | Details |
| RNAG | Unknown (pending investigation) | Unknown (pending investigation) | Sector under investigation | Dissolved Inorganic Nitrogen | Details |
| RNAG | Unknown (pending investigation) | Unknown (pending investigation) | Sector under investigation | Phytoplankton | Details |
| RNAG | Diffuse source | Contaminated water body bed sediments | Water Industry | Tributyltin Compounds | Details |
| RNAG | Diffuse source | Contaminated water body bed sediments | Industry | Tributyltin Compounds | Details |
| RNAG | measures delivered to address reason, awaiting recovery | Not applicable | No sector responsible | Mercury and Its Compounds | Details |
| RNAG | Unknown (pending investigation) | Unknown (pending investigation) | Sector under investigation | Benzo(g-h-i)perylene | Details |
| RNAG | Other pressures | Other (not in list, must add details in comments) | No sector responsible | Polybrominated diphenyl ethers (PBDE) | Details |
| RNAG | Other pressures | Other (not in list, must add details in comments) | No sector responsible | Tributyltin Compounds | Details |
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 issue | Physical modifications | Pollution from waste water | Pollution from towns, cities and transport | Changes to the natural flow and level of water | Invasive non-native species | Pollution from rural areas | Pollution from abandoned mines |
|---|---|---|---|---|---|---|---|
| Agriculture and rural land management | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Industry | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
| Mining and quarrying | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Navigation | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Urban and transport | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Water Industry | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Local & central government | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Domestic general public | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Recreation | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Waste treatment and disposal | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Other | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| No sector responsible | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Sector under investigation | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Total | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
Objectives
| Classification Item | Status | Year | Reasons |
|---|---|---|---|
| Ecological | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens; Technically infeasible: Cause of adverse impact unknown |
| Biological quality elements | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Invertebrates | Good | 2015 | |
| Macroalgae | Good | 2015 | |
| Phytoplankton | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Physico-chemical quality elements | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Dissolved Inorganic Nitrogen | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Dissolved oxygen | Good | 2015 | |
| Hydromorphological Supporting Elements | Supports good | 2015 | |
| Hydrological Regime | Supports good | 2015 | |
| Supporting elements (Surface Water) | Good | 2027 - Low confidence | Technically infeasible: Cause of adverse impact unknown |
| Mitigation Measures Assessment | Good | 2027 - Low confidence | Technically infeasible: Cause of adverse impact unknown |
| Specific pollutants | High | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| 2,4-dichlorophenol | High | 2015 | |
| 2,4-dichlorophenoxyacetic acid | High | 2015 | |
| Arsenic | High | 2015 | |
| Chlorothalonil | High | 2015 | |
| Chromium (VI) | High | 2015 | |
| Copper | High | 2015 | |
| Diazinon | High | 2015 | |
| Dimethoate | High | 2015 | |
| Iron | High | 2015 | |
| Linuron | High | 2015 | |
| Mecoprop | High | 2015 | |
| Pendimethalin | High | 2015 | |
| Permethrin | High | 2015 | |
| Phenol | High | 2015 | |
| Toluene | High | 2015 | |
| Triclosan | High | 2015 | |
| Zinc | High | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Chemical | Good | 2063 | Disproportionately expensive: Disproportionate burdens; Natural conditions: Chemical status recovery time; Technically infeasible: No known technical solution is available |
| Priority hazardous substances | Good | 2063 | Disproportionately expensive: Disproportionate burdens; Natural conditions: Chemical status recovery time; Technically infeasible: No known technical solution is available |
| Anthracene | Good | 2015 | |
| Benzo(a)pyrene | Good | 2015 | |
| Benzo(b)fluoranthene | Good | 2033 | Technically infeasible: No known technical solution is available |
| Benzo(g-h-i)perylene | Good | 2033 | Technically infeasible: No known technical solution is available |
| Benzo(k)fluoranthene | Good | 2015 | |
| Cadmium and Its Compounds | Good | 2015 | |
| Di(2-ethylhexyl)phthalate (Priority hazardous) | Good | 2015 | |
| Dioxins and dioxin-like compounds | Good | 2015 | |
| Endosulfan | Good | 2015 | |
| Heptachlor and cis-Heptachlor epoxide | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Hexabromocyclododecane (HBCDD) | Good | 2015 | |
| Hexachlorobenzene | Good | 2015 | |
| Hexachlorobutadiene | Good | 2015 | |
| Hexachlorocyclohexane | Good | 2015 | |
| Mercury and Its Compounds | Good | 2040 | Natural conditions: Chemical status recovery time |
| Nonylphenol | Good | 2015 | |
| Pentachlorobenzene | Good | 2015 | |
| Perfluorooctane sulphonate (PFOS) | Good | 2015 | |
| Polybrominated diphenyl ethers (PBDE) | Good | 2063 | Natural conditions: Chemical status recovery time |
| Quinoxyfen | Good | 2015 | |
| Tributyltin Compounds | Good | 2021 | Disproportionately expensive: Disproportionate burdens |
| Trifluralin (Priority hazardous) | Good | 2015 | |
| Priority substances | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| 1,2-dichloroethane | Good | 2015 | |
| Aclonifen | Good | 2015 | |
| Alachlor | Good | 2015 | |
| Atrazine | Good | 2015 | |
| Benzene | Good | 2015 | |
| Bifenox | Good | 2015 | |
| Chlorfenvinphos | Good | 2015 | |
| Chlorpyrifos | Good | 2015 | |
| Cybutryne | Good | 2015 | |
| Dichloromethane | Good | 2015 | |
| Dichlorvos (Priority) | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Diuron | Good | 2015 | |
| Fluoranthene | Good | 2015 | |
| Isoproturon | Good | 2015 | |
| Lead and Its Compounds | Good | 2015 | |
| Napthalene | Good | 2015 | |
| Nickel and Its Compounds | Good | 2015 | |
| Octylphenol | Good | 2015 | |
| Pentachlorophenol | Good | 2015 | |
| Simazine | Good | 2015 | |
| Terbutryn | Good | 2015 | |
| Trichlorobenzenes | Good | 2015 | |
| Trichloromethane | Good | 2015 | |
| Other Pollutants | Good | 2015 | |
| Aldrin, Dieldrin, Endrin & Isodrin | Good | 2015 | |
| Carbon Tetrachloride | Good | 2015 | |
| DDT Total | Good | 2015 | |
| Tetrachloroethylene | Good | 2015 | |
| Trichloroethylene | Good | 2015 | |
| para - para DDT | Good | 2015 |
Protected areas
| PA Name | Id | Directive | More information |
|---|---|---|---|
| Mersey Estuary | UK9005131 | Special Protection Area | Natural England |
| Dee Estuary | UK0030131 | Special Area of Conservation | Natural England |
| North Wirral (West) | UKSW110 | Shellfish Water Directive | |
| North Wirral (East) | UKSW109 | Shellfish Water Directive | |
| Mersey Estuary | UK11041 | Ramsar Site | Natural England |
| Liverpool Bay | UK9020294 | Special Protection Area | Natural England |
| Mersey Narrows & North Wirral Foreshore | UK11042 | Ramsar Site | Natural England |
| Mersey Narrows & North Wirral Foreshore | UK9020287 | Special Protection Area | Natural 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.