Chertsey Bourne (Chertsey to River Thames confluence) Water Body
Poor ecological status
Get Chertsey Bourne (Chertsey to River Thames confluence) data
Attributes
- Water Body IDGB106039017030
- Water Body TypeRiver
- Hydromorphological designationnot designated artificial or heavily modified
- NGRTQ0512166123
- Catchment area1224.86 ha
- Length4.928 km
- Catchment area12.249 km2
- Surveillance Water BodyNo
Classifications
| Classification Item | 2019 | 2022 |
|---|---|---|
| Ecological | Poor | Poor |
| Biological quality elements | Poor | Poor |
| Fish | Poor | Poor |
| Invertebrates | High | High |
| Macrophytes and Phytobenthos Combined | Poor | Poor |
| Macrophytes Sub Element | Poor | Poor |
| Physico-chemical quality elements | Moderate | Moderate |
| Ammonia (Phys-Chem) | High | High |
| Biochemical Oxygen Demand (BOD) | High | |
| Dissolved oxygen | Good | Good |
| Phosphate | Poor | Poor |
| Temperature | High | High |
| pH | High | High |
| Hydromorphological Supporting Elements | Supports good | Supports good |
| Hydrological Regime | Supports good | Supports good |
| Specific pollutants | High | High |
| Iron | High | High |
| Triclosan | High | High |
| Chemical | Fail | Does not require assessment |
| Priority hazardous substances | Fail | Does not require assessment |
| Benzo(a)pyrene | 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 | |
| Perfluorooctane sulphonate (PFOS) | Fail | |
| Polybrominated diphenyl ethers (PBDE) | Fail | |
| Tributyltin Compounds | Good | |
| Priority substances | Fail | Does not require assessment |
| Cypermethrin (Priority) | Fail | |
| Fluoranthene | Good | |
| Other Pollutants | Does not require assessment | Does not require assessment |
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 | Point source | Sewage discharge (continuous) | Water Industry | Phosphate | Details |
| RNAG | Point source | Incidents | Water Industry | Dissolved oxygen | Details |
| RNAG | measures delivered to address reason, awaiting recovery | Not applicable | No sector responsible | Polybrominated diphenyl ethers (PBDE) | Details |
| RNAG | Natural | Natural conditions - other | No sector responsible | Dissolved oxygen | Details |
| RNAG | Point source | Sewage discharge (continuous) | Water Industry | Dissolved oxygen | Details |
| RFD | Unknown (pending investigation) | Unknown (pending investigation) | Sector under investigation | Fish | Details |
| RFD | Suspect data | Not applicable | No sector responsible | Fish | Details |
| RNAG | Physical modification | Urbanisation - urban development | Urban and transport | Fish | Details |
| RNAG | Point source | Sewage discharge (continuous) | Water Industry | Macrophytes and Phytobenthos Combined | Details |
| RNAG | Unknown (pending investigation) | Unknown (pending investigation) | Sector under investigation | Perfluorooctane sulphonate (PFOS) | 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 | 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 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
| Water Industry | 0 | 2 | 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 | 1 | 2 | 0 | 0 | 0 | 0 | 0 |
Objectives
| Classification Item | Status | Year | Reasons |
|---|---|---|---|
| Ecological | Moderate | 2039 | Disproportionately expensive: Disproportionate burdens; Natural conditions: Ecological recovery time; Technically infeasible: No known technical solution is available |
| Biological quality elements | Moderate | 2039 | Natural conditions: Ecological recovery time |
| Fish | Good | 2015 | |
| Invertebrates | Good | 2015 | |
| Macrophytes and Phytobenthos Combined | Moderate | 2039 | Natural conditions: Ecological recovery time |
| Physico-chemical quality elements | Moderate | 2015 | Disproportionately expensive: Disproportionate burdens; Technically infeasible: No known technical solution is available |
| Ammonia (Phys-Chem) | Good | 2015 | |
| Dissolved oxygen | Good | 2021 | Disproportionately expensive: Disproportionate burdens |
| Phosphate | Poor | 2015 | Technically infeasible: No known technical solution is available |
| 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 | |
| Iron | High | 2015 | |
| Triclosan | High | 2015 | |
| Chemical | Good | 2063 | Natural conditions: Chemical status recovery time; Technically infeasible: Cause of adverse impact unknown; 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 | |
| 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 | |
| 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 |
| Tributyltin Compounds | Good | 2015 | |
| Priority substances | Good | 2039 | Technically infeasible: Cause of adverse impact unknown |
| Cypermethrin (Priority) | Good | 2039 | Technically infeasible: Cause of adverse impact unknown |
| Fluoranthene | 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 |
Monitoring sites which have been used to classify this water body
Shows which sites were used for classification for which years within each cycle.