Offwell Brook upstream confluence
EA name: RSN1491 OFFWELL BROOK U/S CONFLUENCE (also listed as “RSN1491 OFFWELL BROOK OFFWELL WOOD U/S CONFLUENCE”)
Environment Agency sampling point SW-RSN1491 · Freshwater - rivers · listed as open (“open” does not mean it is sampled now)
These are samples taken on a date, not live readings of the river. Results reach the Environment Agency's archive days to months after the sample is taken, so the newest here may be weeks or months old. FloodRadar does not grade them.
Where and when
- Last sampled
- 5 Dec 2025, 10:4610 months ago · time as the Environment Agency records it (UK clock time; the source gives no time zone). Not sampled since, as far as the archive shows: the Environment Agency was asked up to 30 Sep 2026 and had nothing newer.
- Samples banked
- 12 since 9 Jan 2025 Imported periods: 1 Oct 2023 – 30 Sep 2026. Samples outside them are not shown here.
- Latest sample
- River / running surface water Monitoring (national agency policy)
- Where
- National Grid 319042, 99155As published, to the nearest 1 m. Open in a map
- River, by its own name
- Offwell Brook
- River, by the map
- Offwell BrookPlaced on the river its name gives, 41 m from the line.
- Next gauge downstream
- Bonehayne On the River Coly · 5.9 km along the river
- Why it was sampled
- Monitoring (national agency policy) (12 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
94.3%
Sampled 5 Dec 2025, 10 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Dec 2025, 10:46 | 94.3 | 94.3% |
| 14 Nov 2025, 12:08 | 99 | 99% |
| 16 Oct 2025, 10:29 | 89.5 | 89.5% |
| 18 Sep 2025, 14:55 | 94.7 | 94.7% |
| 7 Aug 2025, 12:24 | 92.2 | 92.2% |
| 16 Jul 2025, 11:12 | 90.3 | 90.3% |
| 18 Jun 2025, 12:33 | 91.7 | 91.7% |
| 9 May 2025, 10:08 | 97.4 | 97.4% |
| 8 Apr 2025, 11:23 | 99.7 | 99.7% |
| 10 Mar 2025, 14:25 | 99 | 99% |
| 12 Feb 2025, 11:59 | 97.4 | 97.4% |
| 9 Jan 2025, 11:47 | 96.5 | 96.5% |
Dissolved oxygen
as O2 · code 9924 · mg/l
11.4 mg/l
Sampled 5 Dec 2025, 10 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Dec 2025, 10:46 | 11.4 | 11.4 mg/l |
| 14 Nov 2025, 12:08 | 10.6 | 10.6 mg/l |
| 16 Oct 2025, 10:29 | 9.92 | 9.92 mg/l |
| 18 Sep 2025, 14:55 | 9.65 | 9.65 mg/l |
| 7 Aug 2025, 12:24 | 9.5 | 9.5 mg/l |
| 16 Jul 2025, 11:12 | 9.24 | 9.24 mg/l |
| 18 Jun 2025, 12:33 | 9.55 | 9.55 mg/l |
| 9 May 2025, 10:08 | 11.1 | 11.1 mg/l |
| 8 Apr 2025, 11:23 | 11.4 | 11.4 mg/l |
| 10 Mar 2025, 14:25 | 11.2 | 11.2 mg/l |
| 12 Feb 2025, 11:59 | 12 | 12 mg/l |
| 9 Jan 2025, 11:47 | 12.4 | 12.4 mg/l |
Water temperature
code 0076 · °C
7.2 °C
Sampled 5 Dec 2025, 10 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Dec 2025, 10:46 | 7.2 | 7.2 °C |
| 14 Nov 2025, 12:08 | 12.2 | 12.2 °C |
| 16 Oct 2025, 10:29 | 10.7 | 10.7 °C |
| 18 Sep 2025, 14:55 | 14.4 | 14.4 °C |
| 7 Aug 2025, 12:24 | 13.9 | 13.9 °C |
| 16 Jul 2025, 11:12 | 14.2 | 14.2 °C |
| 18 Jun 2025, 12:33 | 13.4 | 13.4 °C |
| 9 May 2025, 10:08 | 9.5 | 9.5 °C |
| 8 Apr 2025, 11:23 | 9.2 | 9.2 °C |
| 10 Mar 2025, 14:25 | 9.9 | 9.9 °C |
| 12 Feb 2025, 11:59 | 6.5 | 6.5 °C |
| 9 Jan 2025, 11:47 | 4.7 | 4.7 °C |
pH
code 0061
7.05
Sampled 5 Dec 2025, 10 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Dec 2025, 10:46 | 7.05 | 7.05 |
| 14 Nov 2025, 12:08 | 7.83 | 7.83 |
| 16 Oct 2025, 10:29 | 7.1 | 7.1 |
| 18 Sep 2025, 14:55 | 7.4 | 7.4 |
| 7 Aug 2025, 12:24 | 6.97 | 6.97 |
| 16 Jul 2025, 11:12 | 7.22 | 7.22 |
| 18 Jun 2025, 12:33 | 7.34 | 7.34 |
| 9 May 2025, 10:08 | 7.37 | 7.37 |
| 8 Apr 2025, 11:23 | 7.54 | 7.54 |
| 10 Mar 2025, 14:25 | 7.18 | 7.18 |
| 12 Feb 2025, 11:59 | 7.58 | 7.58 |
| 9 Jan 2025, 11:47 | 7.6 | 7.6 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
0.0052 mg/l
Sampled 5 Dec 2025, 10 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Dec 2025, 10:46 | 0.0052 | 0.0052 mg/l |
| 14 Nov 2025, 12:08 | 0.0046 | 0.0046 mg/l |
| 16 Oct 2025, 10:29 | 0.0021 | 0.0021 mg/l |
| 18 Sep 2025, 14:55 | <0.002 | below 0.002 mg/l (not detected above this) |
| 7 Aug 2025, 12:24 | <0.002 | below 0.002 mg/l (not detected above this) |
| 16 Jul 2025, 11:12 | 0.0029 | 0.0029 mg/l |
| 18 Jun 2025, 12:33 | 0.0021 | 0.0021 mg/l |
| 9 May 2025, 10:08 | <0.002 | below 0.002 mg/l (not detected above this) |
| 8 Apr 2025, 11:23 | 0.009 | 0.009 mg/l |
| 10 Mar 2025, 14:25 | 0.0039 | 0.0039 mg/l |
| 12 Feb 2025, 11:59 | 0.0049 | 0.0049 mg/l |
| 9 Jan 2025, 11:47 | 0.007 | 0.007 mg/l |
Nitrate
as nitrogen (N) · code 0117 · mg/l
1.3 mg/l
Sampled 5 Dec 2025, 10 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Dec 2025, 10:46 | 1.3 | 1.3 mg/l |
| 14 Nov 2025, 12:08 | 1.4 | 1.4 mg/l |
| 16 Oct 2025, 10:29 | 0.999 | 0.999 mg/l |
| 18 Sep 2025, 14:55 | 1.1 | 1.1 mg/l |
| 7 Aug 2025, 12:24 | 1.2 | 1.2 mg/l |
| 16 Jul 2025, 11:12 | 1.3 | 1.3 mg/l |
| 18 Jun 2025, 12:33 | 1.4 | 1.4 mg/l |
| 9 May 2025, 10:08 | 1.4 | 1.4 mg/l |
| 8 Apr 2025, 11:23 | 1.3 | 1.3 mg/l |
| 10 Mar 2025, 14:25 | 1.5 | 1.5 mg/l |
| 12 Feb 2025, 11:59 | 1.6 | 1.6 mg/l |
| 9 Jan 2025, 11:47 | 1.9 | 1.9 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.019 mg/l
Sampled 5 Dec 2025, 10 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Dec 2025, 10:46 | 0.019 | 0.019 mg/l |
| 14 Nov 2025, 12:08 | 0.047 | 0.047 mg/l |
| 16 Oct 2025, 10:29 | 0.0037 | 0.0037 mg/l |
| 18 Sep 2025, 14:55 | 0.0058 | 0.0058 mg/l |
| 7 Aug 2025, 12:24 | 0.0073 | 0.0073 mg/l |
| 16 Jul 2025, 11:12 | 0.016 | 0.016 mg/l |
| 18 Jun 2025, 12:33 | 0.0071 | 0.0071 mg/l |
| 9 May 2025, 10:08 | 0.0073 | 0.0073 mg/l |
| 8 Apr 2025, 11:23 | 0.034 | 0.034 mg/l |
| 10 Mar 2025, 14:25 | 0.0079 | 0.0079 mg/l |
| 12 Feb 2025, 11:59 | 0.0075 | 0.0075 mg/l |
| 9 Jan 2025, 11:47 | 0.026 | 0.026 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
160 µS/cm
Sampled 5 Dec 2025, 10 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Dec 2025, 10:46 | 160 | 160 µS/cm |
| 14 Nov 2025, 12:08 | 172 | 172 µS/cm |
| 16 Oct 2025, 10:29 | 152 | 152 µS/cm |
| 18 Sep 2025, 14:55 | 158 | 158 µS/cm |
| 7 Aug 2025, 12:24 | 167 | 167 µS/cm |
| 16 Jul 2025, 11:12 | 175 | 175 µS/cm |
| 18 Jun 2025, 12:33 | 182 | 182 µS/cm |
| 9 May 2025, 10:08 | 154 | 154 µS/cm |
| 8 Apr 2025, 11:23 | 162 | 162 µS/cm |
| 10 Mar 2025, 14:25 | 162 | 162 µS/cm |
| 12 Feb 2025, 11:59 | 136 | 136 µS/cm |
| 9 Jan 2025, 11:47 | 180 | 180 µS/cm |
Everything measured here
18 determinands, each kept by its code, unit and sample material: results in different units or on different materials are never mixed. A “below” result is under the laboratory's detection limit, not zero.
Show all 18 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 12 | Jan 2025 – Dec 2025 | 94.3% 5 Dec 2025 |
| Oxygen, Dissolved as O2 9924 | River water | 12 | Jan 2025 – Dec 2025 | 11.4 mg/l 5 Dec 2025 |
| Temperature of Water 0076 | River water | 12 | Jan 2025 – Dec 2025 | 7.2 °C 5 Dec 2025 |
| pH 0061 | River water | 12 | Jan 2025 – Dec 2025 | 7.05 5 Dec 2025 |
| Ammoniacal Nitrogen as N 0111 | River water | 12 | Jan 2025 – Dec 2025 | 0.0052 mg/l 5 Dec 2025 |
| Nitrate as N 0117 | River water | 12 | Jan 2025 – Dec 2025 | 1.3 mg/l 5 Dec 2025 |
| Orthophosphate, reactive as P 0180 | River water | 12 | Jan 2025 – Dec 2025 | 0.019 mg/l 5 Dec 2025 |
| Conductivity at 25 C 0077 | River water | 12 | Jan 2025 – Dec 2025 | 160 µS/cm 5 Dec 2025 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 12 | Jan 2025 – Dec 2025 | 33 mg/l 5 Dec 2025 |
| Ammonia un-ionised as N 0119 | River water | 12 | Jan 2025 – Dec 2025 | below 0.00001 mg/l 5 Dec 2025 |
| Carbon, Organic, Dissolved as C :- {DOC} 0301 | River water | 12 | Jan 2025 – Dec 2025 | 4.7 mg/l 5 Dec 2025 |
| Chloride 0172 | River water | 12 | Jan 2025 – Dec 2025 | 20 mg/l 5 Dec 2025 |
| Flow Type 2896 | River water | 12 | Jan 2025 – Dec 2025 | Moderate Flow 5 Dec 2025 |
| Nitrite as N 0118 | River water | 12 | Jan 2025 – Dec 2025 | below 0.001 mg/l 5 Dec 2025 |
| Nitrogen, Total Oxidised as N 0116 | River water | 12 | Jan 2025 – Dec 2025 | 1.3 mg/l 5 Dec 2025 |
| Phosphorus, Total as P 0348 | River water | 12 | Jan 2025 – Dec 2025 | 0.033 mg/l 5 Dec 2025 |
| Silica, reactive as SiO2 0182 | River water | 12 | Jan 2025 – Dec 2025 | 14 mg/l 5 Dec 2025 |
| Solids, Suspended at 105 C 0135 | River water | 1 | Dec 2025 – Dec 2025 | below 3 mg/l 5 Dec 2025 |
FloodRadar does not grade these results: there is no overall score, and official river classifications are a separate dataset. A sample taken downstream of an overflow does not by itself show where anything in it came from. River connections and distances are traced on OS Open Rivers (edition 2026-04), which leaves out many small channels.
Water samples: Environment Agency Water Quality Archive, © Environment Agency and/or database right 2026, Open Government Licence v3.0.
Contains OS data © Crown copyright and database rights 2026.