Henlow Brook Water Body
Moderate ecological status
Get Henlow Brook data
Attributes
- Water Body IDGB105033037770
- Water Body TypeRiver
- Hydromorphological designationheavily modified
- NGRTL1753538153
- Catchment area1594.722 ha
- Length8.687 km
- Catchment area15.947 km2
- Surveillance Water BodyNo
Classifications
| Classification Item | 2019 | 2022 |
|---|---|---|
| Ecological | Moderate | Moderate |
| Biological quality elements | Good | Good |
| Invertebrates | Good | Good |
| Macrophytes and Phytobenthos Combined | ||
| Macrophytes Sub Element | Poor | Poor |
| Physico-chemical quality elements | Moderate | Moderate |
| Ammonia (Phys-Chem) | High | 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 |
| Supporting elements (Surface Water) | Moderate | Moderate |
| Mitigation Measures Assessment | Moderate or less | Moderate or less |
| Specific pollutants | Moderate | Moderate |
| Iron | Moderate | Moderate |
| Manganese | High | High |
| Triclosan | 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 | Good | |
| Benzo(k)fluoranthene | 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) | Good | |
| Polybrominated diphenyl ethers (PBDE) | Fail | |
| Tributyltin Compounds | Good | |
| Priority substances | Good | Does not require assessment |
| Cypermethrin (Priority) | Good | |
| Fluoranthene | Good | |
| Other Pollutants | Does not require assessment | Does not require assessment |
Investigations into classification status
| Classification Element | Cycle | Year | Status | Outcome |
|---|---|---|---|---|
| Dissolved oxygen | 2 | 2014 | Poor | Quite certain there is 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 |
|---|---|---|---|---|---|
| RFD | Suspect data | Not applicable | No sector responsible | Iron | Details |
| RNAG | Physical modification | Land drainage - operational management | Agriculture and rural land management | Invertebrates | Details |
| RNAG | Point source | Sewage discharge (continuous) | Other | Phosphate | Details |
| RNAG | Point source | Sewage discharge (continuous) | Water Industry | Phosphate | Details |
| RNAG | measures delivered to address reason, awaiting recovery | Not applicable | No sector responsible | Polybrominated diphenyl ethers (PBDE) | Details |
| RNAG | Flow | Land drainage | Agriculture and rural land management | Invertebrates | Details |
| RNAG | Point source | Sewage discharge (continuous) | Other | Invertebrates | Details |
| RNAG | Suspect data | Not applicable | No sector responsible | Iron | Details |
| RNAG | Invasive non-native species | North american signal crayfish | No sector responsible | Invertebrates | Details |
| RNAG | Diffuse source | Poor soil management | Agriculture and rural land management | Invertebrates | Details |
| RNAG | Point source | Sewage discharge (continuous) | Water Industry | Invertebrates | 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 | 1 | 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 | 1 | 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 | 2 | 0 | 0 | 0 | 0 | 0 |
Objectives
| Classification Item | Status | Year | Reasons |
|---|---|---|---|
| Ecological | Moderate | 2015 | Disproportionately expensive: Disproportionate burdens; Disproportionately expensive: Unfavourable balance of costs and benefits; Technically infeasible: No known technical solution is available |
| Biological quality elements | Good | 2021 | Disproportionately expensive: Disproportionate burdens; Disproportionately expensive: Unfavourable balance of costs and benefits |
| Invertebrates | Good | 2021 | Disproportionately expensive: Disproportionate burdens |
| Macrophytes and Phytobenthos Combined | Not assessed | 2015 | Disproportionately expensive: Unfavourable balance of costs and benefits |
| 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) | Good | 2015 | |
| Mitigation Measures Assessment | Good | 2015 | |
| Specific pollutants | High | 2015 | |
| Iron | High | 2015 | |
| Manganese | High | 2015 | |
| Triclosan | High | 2015 | |
| Chemical | Good | 2063 | Natural conditions: Chemical status recovery time |
| Priority hazardous substances | Good | 2063 | Natural conditions: Chemical status recovery time |
| Benzo(a)pyrene | Good | 2015 | |
| Benzo(b)fluoranthene | Good | 2015 | |
| Benzo(g-h-i)perylene | Good | 2015 | |
| Benzo(k)fluoranthene | 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 | 2015 | |
| Polybrominated diphenyl ethers (PBDE) | Good | 2063 | Natural conditions: Chemical status recovery time |
| Tributyltin Compounds | Good | 2015 | |
| Priority substances | Good | 2015 | |
| Cypermethrin (Priority) | Good | 2015 | |
| Fluoranthene | Good | 2015 | |
| Other Pollutants | Does not require assessment | 2015 |
Protected areas
| PA Name | Id | Directive | More information |
|---|---|---|---|
| Great Ouse NVZ | S391 | Nitrates Directive | |
| Woburn Sands | G76 | 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.