Ewelme Stream (Source to Thames) Water Body
Moderate ecological status
Get Ewelme Stream (Source to Thames) data
Attributes
- Water Body IDGB106039023610
- Water Body TypeRiver
- Hydromorphological designationnot designated artificial or heavily modified
- NGRSU6287792132
- Catchment area1513.79 ha
- Length3.704 km
- Catchment area15.138 km2
- Surveillance Water BodyNo
Classifications
| Classification Item | 2019 |
|---|---|
| Ecological | Moderate |
| Biological quality elements | Moderate |
| Fish | Moderate |
| Invertebrates | High |
| Macrophytes and Phytobenthos Combined | Good |
| Macrophytes Sub Element | Good |
| Physico-chemical quality elements | Moderate |
| Ammonia (Phys-Chem) | High |
| Dissolved oxygen | High |
| Phosphate | Moderate |
| Temperature | High |
| pH | High |
| Hydromorphological Supporting Elements | Supports good |
| Hydrological Regime | High |
| Chemical | Fail |
| Priority hazardous substances | Fail |
| 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 | Fail |
| Perfluorooctane sulphonate (PFOS) | Fail |
| Polybrominated diphenyl ethers (PBDE) | Fail |
| Priority substances | Fail |
| Cypermethrin (Priority) | Fail |
| Fluoranthene | Good |
| Other Pollutants | 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 | measures delivered to address reason, awaiting recovery | Not applicable | No sector responsible | Mercury and Its Compounds | Details |
| RNAG | measures delivered to address reason, awaiting recovery | Not applicable | No sector responsible | Polybrominated diphenyl ethers (PBDE) | Details |
| RNAG | Physical modification | Urbanisation - urban development | Other | Fish | Details |
| RNAG | Physical modification | Barriers - ecological discontinuity | Other | Fish | 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 | 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 | 2 | 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 | 2 | 0 | 0 | 0 | 0 | 0 | 0 |
Objectives
| Classification Item | Status | Year | Reasons |
|---|---|---|---|
| Ecological | Moderate | 2015 | 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 elements | Moderate | 2015 | Good status prevented by A/HMWB designated use: Action to get biological element to good would have significant adverse impact on use |
| Fish | Moderate | 2015 | Good status prevented by A/HMWB designated use: Action to get biological element to good would have significant adverse impact on use |
| Invertebrates | Good | 2015 | |
| Macrophytes and Phytobenthos Combined | Good | 2015 | |
| Physico-chemical quality elements | Moderate | 2015 | Disproportionately expensive: Unfavourable balance of costs and benefits |
| Ammonia (Phys-Chem) | Good | 2015 | |
| Dissolved oxygen | Good | 2015 | |
| Phosphate | Moderate | 2015 | Disproportionately expensive: Unfavourable balance of costs and benefits |
| 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 | Not assessed | 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 | 2040 | Natural conditions: Chemical status recovery time |
| 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 | 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 |
|---|---|---|---|
| Thames Wallingford to Caversham NVZ | S481 | Nitrates Directive | |
| Ewelme Stream (Source to Thames) NVZ | S804 | 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.