Colne (upper east arm including Mimshall Brook) Water Body
Bad ecological status
Get Colne (upper east arm including Mimshall Brook) data
Attributes
- Water Body IDGB106039029850
- Water Body TypeRiver
- Hydromorphological designationnot designated artificial or heavily modified
- NGRTL2312402069
- Catchment area60.996 km2
- Surveillance Water BodyNo
- Length24.709 km
- Catchment area6099.64 ha
Classifications
| Classification Item | 2019 | 2022 |
|---|---|---|
| Ecological | Bad | Bad |
| Biological quality elements | Bad | Bad |
| Fish | Bad | Bad |
| Invertebrates | Poor | Poor |
| Macrophytes and Phytobenthos Combined | Moderate | Moderate |
| Macrophytes Sub Element | Moderate | Moderate |
| Physico-chemical quality elements | Moderate | Moderate |
| Ammonia (Phys-Chem) | High | High |
| Dissolved oxygen | High | High |
| Phosphate | Moderate | Moderate |
| Temperature | High | High |
| pH | High | High |
| Hydromorphological Supporting Elements | Supports good | Supports good |
| Hydrological Regime | Does not support good | Does not support good |
| Morphology | Supports good | Supports good |
| Specific pollutants | High | High |
| Copper | High | High |
| Iron | High | High |
| Manganese | High | High |
| Triclosan | High | High |
| Zinc | High | High |
| Chemical | Fail | Does not require assessment |
| Priority hazardous substances | Fail | Does not require assessment |
| Benzo(a)pyrene | Good | |
| Benzo(b)fluoranthene | Good | |
| 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 | |
| Heptachlor and cis-Heptachlor epoxide | Good | |
| Hexabromocyclododecane (HBCDD) | Good | |
| Hexachlorobenzene | Good | |
| Hexachlorobutadiene | Good | |
| Mercury and Its Compounds | Good | |
| Nonylphenol | Good | |
| Perfluorooctane sulphonate (PFOS) | Fail | |
| Polybrominated diphenyl ethers (PBDE) | Fail | |
| Priority substances | Good | Does not require assessment |
| Cypermethrin (Priority) | Good | |
| Fluoranthene | Good | |
| Lead and Its Compounds | Good | |
| Nickel and Its Compounds | Good | |
| Other Pollutants | Does not require assessment | Does not require assessment |
Investigations into classification status
| Classification Element | Cycle | Year | Status | Outcome |
|---|---|---|---|---|
| Hydrological Regime | 2 | 2019 | Does Not Support Good | Certain 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 Type | SWMI | Activity | Category | Classification Element | More information |
|---|---|---|---|---|---|
| RNAG | Diffuse source | Poor Livestock Management | Agriculture and rural land management | Phosphate | Details |
| RNAG | Point source | Private Sewage Treatment | Other | Phosphate | Details |
| RNAG | Point source | Sewage discharge (intermittent) | Water Industry | Phosphate | Details |
| RNAG | Diffuse source | Urbanisation - urban development | Urban and transport | Phosphate | Details |
| RNAG | Natural | Natural conditions - other | No sector responsible | Fish | Details |
| RNAG | Physical modification | Urbanisation - transport | Urban and transport | Invertebrates | Details |
| RNAG | Unknown (pending investigation) | Unknown (pending investigation) | Sector under investigation | Perfluorooctane sulphonate (PFOS) | Details |
| RNAG | Physical modification | Urbanisation - urban development | Urban and transport | Invertebrates | Details |
| RNAG | Unknown (pending investigation) | Unknown (pending investigation) | Sector under investigation | Benzo(g-h-i)perylene | Details |
| RNAG | measures delivered to address reason, awaiting recovery | Not applicable | No sector responsible | Polybrominated diphenyl ethers (PBDE) | Details |
| RNAG | Natural | Drought | No sector responsible | Invertebrates | Details |
| RNAG | Natural | Natural conditions - other | No sector responsible | Hydrological Regime | Details |
| RNAG | Diffuse source | Transport Drainage | Urban and transport | Invertebrates | Details |
| RNAG | Physical modification | Flood protection - structures | Urban and transport | Macrophytes and Phytobenthos Combined | Details |
| RNAG | Diffuse source | Poor soil management | Agriculture and rural land management | Invertebrates | Details |
| RNAG | Physical modification | Urbanisation - urban development | Urban and transport | Macrophytes and Phytobenthos Combined | Details |
| RNAG | Point source | Misconnections | Domestic General Public | Invertebrates | Details |
| RNAG | Natural | Drought | No sector responsible | Invertebrates | Details |
| RNAG | Diffuse source | Transport Drainage | Urban and transport | Invertebrates | Details |
| RNAG | Diffuse source | Transport Drainage | Urban and transport | Fish | Details |
| RNAG | Invasive non-native species | Other plants | No sector responsible | Macrophytes and Phytobenthos Combined | Details |
| RNAG | Point source | Private Sewage Treatment | Other | Macrophytes and Phytobenthos Combined | Details |
| RNAG | Diffuse source | Poor nutrient management | Agriculture and rural land management | Invertebrates | Details |
| RNAG | Diffuse source | Poor soil management | Agriculture and rural land management | Fish | Details |
| RNAG | Physical modification | Urbanisation - urban development | Urban and transport | Fish | Details |
| RNAG | Point source | Sewage discharge (intermittent) | Water Industry | Macrophytes and Phytobenthos Combined | Details |
| RNAG | Diffuse source | Urbanisation - urban development | Urban and transport | Macrophytes and Phytobenthos Combined | Details |
| RNAG | Physical modification | Flood protection - structures | Local and Central Government | Invertebrates | Details |
| RNAG | Diffuse source | Poor Livestock Management | Agriculture and rural land management | Macrophytes and Phytobenthos Combined | 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 | 3 | 0 |
| Industry | 0 | 0 | 0 | 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 | 4 | 0 | 3 | 0 | 0 | 0 | 0 |
| Water Industry | 0 | 2 | 0 | 0 | 0 | 0 | 0 |
| Local & central government | 1 | 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 | 2 | 0 | 0 | 0 | 0 |
| No sector responsible | 0 | 0 | 0 | 0 | 1 | 0 | 0 |
| Sector under investigation | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Total | 5 | 2 | 5 | 0 | 1 | 3 | 0 |
Objectives
| Classification Item | Status | Year | Reasons |
|---|---|---|---|
| Ecological | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Biological quality elements | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Fish | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Invertebrates | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Macrophytes and Phytobenthos Combined | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Physico-chemical quality elements | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Ammonia (Phys-Chem) | Good | 2015 | |
| Dissolved oxygen | Good | 2015 | |
| Phosphate | Good | 2027 - Low confidence | Disproportionately expensive: Disproportionate burdens |
| Temperature | Good | 2015 | |
| pH | Good | 2015 | |
| Hydromorphological Supporting Elements | Supports good | 2015 | |
| Hydrological Regime | Supports good | 2015 | |
| Supporting elements (Surface Water) | Not assessed | 2015 | |
| Specific pollutants | High | 2015 | |
| Copper | High | 2015 | |
| Iron | High | 2015 | |
| Manganese | High | 2015 | |
| Triclosan | High | 2015 | |
| Zinc | High | 2015 | |
| Chemical | Good | 2063 | Natural conditions: Chemical status recovery time; Technically infeasible: No known technical solution is available |
| Priority hazardous substances | Good | 2063 | Natural conditions: Chemical status recovery time; Technically infeasible: No known technical solution is available |
| Benzo(a)pyrene | Good | 2015 | |
| Benzo(b)fluoranthene | Good | 2015 | |
| 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 | |
| Heptachlor and cis-Heptachlor epoxide | Good | 2015 | |
| Hexabromocyclododecane (HBCDD) | Good | 2015 | |
| Hexachlorobenzene | Good | 2015 | |
| Hexachlorobutadiene | Good | 2015 | |
| Mercury and Its Compounds | Good | 2015 | |
| Nonylphenol | Good | 2015 | |
| Perfluorooctane sulphonate (PFOS) | Good | 2039 | Technically infeasible: No known technical solution is available |
| Polybrominated diphenyl ethers (PBDE) | Good | 2063 | Natural conditions: Chemical status recovery time |
| Priority substances | Good | 2015 | |
| Cypermethrin (Priority) | Good | 2015 | |
| Fluoranthene | Good | 2015 | |
| Lead and Its Compounds | Good | 2015 | |
| Nickel and Its Compounds | Good | 2015 | |
| Other Pollutants | Does not require assessment | 2015 |
Protected areas
| PA Name | Id | Directive | More information |
|---|---|---|---|
| Lower Thames (Cookham Egham Teddington) | SWSGZ4016 | Safeguard Zone | |
| North Mymms | G92 | Nitrates 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.