Olchon Brook, Longtown Castle
EA name: OLCHON BROOK, LONGTOWN CASTLE (also listed as “RSN1823 OLCHON BROOK, LONGTOWN CASTLE”)
Environment Agency sampling point MD-RSN1823 · 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
- 7 Jul 2026, 11:183 months ago · time as the Environment Agency records it (UK clock time; the source gives no time zone)
- Samples banked
- 27 since 18 Oct 2023 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 331700, 229151As published, to the nearest 1 m. Open in a map
- River, by its own name
- Olchon Brook
- River, by the map
- Olchon BrookPlaced on the river its name gives, 5 m from the line.
- Next gauge downstream
- Grosmont Rhosllwyn River Station On the Monnow · 22 km along the river
- Why it was sampled
- Monitoring (national agency policy) (19 samples)
Environmental monitoring statutory (EU directives) (8 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
101.3%
Sampled 7 Jul 2026, 3 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 Jul 2026, 11:18 | 101.3 | 101.3% |
| 17 Jun 2026, 12:13 | 100.4 | 100.4% |
| 5 May 2026, 12:24 | 106.7 | 106.7% |
| 10 Mar 2026, 10:58 | 104.1 | 104.1% |
| 18 Feb 2026, 14:07 | 99.3 | 99.3% |
| 26 Jan 2026, 10:48 | 101.1 | 101.1% |
| 18 Dec 2025, 11:36 | 101.3 | 101.3% |
| 27 Nov 2025, 11:00 | 99.7 | 99.7% |
| 3 Oct 2025, 11:46 | 83.4 | 83.4% |
| 9 Sep 2025, 10:40 | 94.6 | 94.6% |
| 12 Aug 2025, 10:31 | 92.7 | 92.7% |
| 10 Jul 2025, 10:48 | 94.9 | 94.9% |
| 23 Jun 2025, 10:21 | 94.6 | 94.6% |
| 29 May 2025, 11:28 | 97.2 | 97.2% |
| 29 May 2025, 11:27 | 98.8 | 98.8% |
| 8 Apr 2025, 10:55 | 104.1 | 104.1% |
| 24 Mar 2025, 10:49 | 103.3 | 103.3% |
| 29 Oct 2024, 13:16 | 95.1 | 95.1% |
| 18 Sep 2024, 11:05 | 95.8 | 95.8% |
| 25 Jun 2024, 10:35 | 98.2 | 98.2% |
| 23 May 2024, 11:10 | 98.9 | 98.9% |
| 29 Apr 2024, 11:14 | 104.3 | 104.3% |
| 29 Apr 2024, 11:06 | 103.6 | 103.6% |
| 15 Jan 2024, 11:31 | 100.7 | 100.7% |
| 8 Dec 2023, 11:55 | 101.5 | 101.5% |
| 23 Nov 2023, 13:04 | 101 | 101% |
| 18 Oct 2023, 11:19 | 98.4 | 98.4% |
Dissolved oxygen
as O2 · code 9924 · mg/l
9.7 mg/l
Sampled 7 Jul 2026, 3 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 Jul 2026, 11:18 | 9.7 | 9.7 mg/l |
| 17 Jun 2026, 12:13 | 9.88 | 9.88 mg/l |
| 5 May 2026, 12:24 | 11.3 | 11.3 mg/l |
| 10 Mar 2026, 10:58 | 12.1 | 12.1 mg/l |
| 18 Feb 2026, 14:07 | 12.7 | 12.7 mg/l |
| 26 Jan 2026, 10:48 | 12.7 | 12.7 mg/l |
| 18 Dec 2025, 11:36 | 11.7 | 11.7 mg/l |
| 27 Nov 2025, 11:00 | 11.3 | 11.3 mg/l |
| 3 Oct 2025, 11:46 | 8.77 | 8.77 mg/l |
| 9 Sep 2025, 10:40 | 9.9 | 9.9 mg/l |
| 12 Aug 2025, 10:31 | 9.16 | 9.16 mg/l |
| 10 Jul 2025, 10:48 | 9.46 | 9.46 mg/l |
| 23 Jun 2025, 10:21 | 9.62 | 9.62 mg/l |
| 29 May 2025, 11:28 | 10.2 | 10.2 mg/l |
| 29 May 2025, 11:27 | 10.3 | 10.3 mg/l |
| 8 Apr 2025, 10:55 | 12.6 | 12.6 mg/l |
| 24 Mar 2025, 10:49 | 12.2 | 12.2 mg/l |
| 29 Oct 2024, 13:16 | 10.4 | 10.4 mg/l |
| 18 Sep 2024, 11:05 | 10.1 | 10.1 mg/l |
| 25 Jun 2024, 10:35 | 10.1 | 10.1 mg/l |
| 23 May 2024, 11:10 | 10.9 | 10.9 mg/l |
| 29 Apr 2024, 11:14 | 12.1 | 12.1 mg/l |
| 29 Apr 2024, 11:06 | 12 | 12 mg/l |
| 15 Jan 2024, 11:31 | 13.2 | 13.2 mg/l |
| 8 Dec 2023, 11:55 | 12 | 12 mg/l |
| 23 Nov 2023, 13:04 | 11.3 | 11.3 mg/l |
| 18 Oct 2023, 11:19 | 11.2 | 11.2 mg/l |
Water temperature
code 0076 · °C
17.3 °C
Sampled 7 Jul 2026, 3 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 Jul 2026, 11:18 | 17.3 | 17.3 °C |
| 17 Jun 2026, 12:13 | 16 | 16 °C |
| 5 May 2026, 12:24 | 12.5 | 12.5 °C |
| 10 Mar 2026, 10:58 | 8.8 | 8.8 °C |
| 18 Feb 2026, 14:07 | 4.8 | 4.8 °C |
| 26 Jan 2026, 10:48 | 5.7 | 5.7 °C |
| 18 Dec 2025, 11:36 | 8.8 | 8.8 °C |
| 27 Nov 2025, 11:00 | 9.7 | 9.7 °C |
| 3 Oct 2025, 11:46 | 13 | 13 °C |
| 9 Sep 2025, 10:40 | 13.2 | 13.2 °C |
| 12 Aug 2025, 10:31 | 15.8 | 15.8 °C |
| 10 Jul 2025, 10:48 | 15.4 | 15.4 °C |
| 23 Jun 2025, 10:21 | 14.5 | 14.5 °C |
| 29 May 2025, 11:28 | 13.1 | 13.1 °C |
| 29 May 2025, 11:27 | 13.5 | 13.5 °C |
| 8 Apr 2025, 10:55 | 7 | 7 °C |
| 24 Mar 2025, 10:49 | 7.9 | 7.9 °C |
| 29 Oct 2024, 13:16 | 11.3 | 11.3 °C |
| 18 Sep 2024, 11:05 | 12.7 | 12.7 °C |
| 25 Jun 2024, 10:35 | 14 | 14 °C |
| 23 May 2024, 11:10 | 10.8 | 10.8 °C |
| 29 Apr 2024, 11:14 | 8.8 | 8.8 °C |
| 29 Apr 2024, 11:06 | 8.9 | 8.9 °C |
| 15 Jan 2024, 11:31 | 3.9 | 3.9 °C |
| 8 Dec 2023, 11:55 | 8 | 8 °C |
| 23 Nov 2023, 13:04 | 10.3 | 10.3 °C |
| 18 Oct 2023, 11:19 | 9.5 | 9.5 °C |
pH
code 0061
8.34
Sampled 7 Jul 2026, 3 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 Jul 2026, 11:18 | 8.34 | 8.34 |
| 17 Jun 2026, 12:13 | 8.36 | 8.36 |
| 5 May 2026, 12:24 | 8.49 | 8.49 |
| 10 Mar 2026, 10:58 | 8.52 | 8.52 |
| 18 Feb 2026, 14:07 | 8.29 | 8.29 |
| 26 Jan 2026, 10:48 | 8.29 | 8.29 |
| 18 Dec 2025, 11:36 | 8.02 | 8.02 |
| 27 Nov 2025, 11:00 | 8.26 | 8.26 |
| 3 Oct 2025, 11:46 | 7.7 | 7.7 |
| 9 Sep 2025, 10:40 | 8.17 | 8.17 |
| 12 Aug 2025, 10:31 | 8.11 | 8.11 |
| 10 Jul 2025, 10:48 | 8.25 | 8.25 |
| 23 Jun 2025, 10:21 | 8.18 | 8.18 |
| 29 May 2025, 11:28 | 8.16 | 8.16 |
| 29 May 2025, 11:27 | 8.13 | 8.13 |
| 8 Apr 2025, 10:55 | 8.43 | 8.43 |
| 24 Mar 2025, 10:49 | 8.49 | 8.49 |
| 29 Oct 2024, 13:16 | 8.17 | 8.17 |
| 18 Sep 2024, 11:05 | 8.13 | 8.13 |
| 25 Jun 2024, 10:35 | 8.22 | 8.22 |
| 23 May 2024, 11:10 | 8.34 | 8.34 |
| 29 Apr 2024, 11:14 | 8.54 | 8.54 |
| 29 Apr 2024, 11:06 | 8.59 | 8.59 |
| 15 Jan 2024, 11:31 | 8.35 | 8.35 |
| 8 Dec 2023, 11:55 | 7.99 | 7.99 |
| 23 Nov 2023, 13:04 | 8.03 | 8.03 |
| 18 Oct 2023, 11:19 | 8.25 | 8.25 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
0.0049 mg/l
Sampled 7 Jul 2026, 3 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 Jul 2026, 11:18 | 0.0049 | 0.0049 mg/l |
| 17 Jun 2026, 12:13 | <0.002 | below 0.002 mg/l (not detected above this) |
| 5 May 2026, 12:24 | 0.0068 | 0.0068 mg/l |
| 10 Mar 2026, 10:58 | 0.01 | 0.01 mg/l |
| 18 Feb 2026, 14:07 | 0.0062 | 0.0062 mg/l |
| 26 Jan 2026, 10:48 | 0.0038 | 0.0038 mg/l |
| 18 Dec 2025, 11:36 | 0.014 | 0.014 mg/l |
| 27 Nov 2025, 11:00 | <0.002 | below 0.002 mg/l (not detected above this) |
| 3 Oct 2025, 11:46 | 0.054 | 0.054 mg/l |
| 9 Sep 2025, 10:40 | 0.0043 | 0.0043 mg/l |
| 12 Aug 2025, 10:31 | <0.002 | below 0.002 mg/l (not detected above this) |
| 10 Jul 2025, 10:48 | 0.0096 | 0.0096 mg/l |
| 23 Jun 2025, 10:21 | <0.002 | below 0.002 mg/l (not detected above this) |
| 29 May 2025, 11:28 | <0.03 | below 0.03 mg/l (not detected above this) |
| 29 May 2025, 11:27 | 0.027 | 0.027 mg/l |
| 8 Apr 2025, 10:55 | 0.0055 | 0.0055 mg/l |
| 24 Mar 2025, 10:49 | 0.0048 | 0.0048 mg/l |
| 29 Oct 2024, 13:16 | <0.002 | below 0.002 mg/l (not detected above this) |
| 18 Sep 2024, 11:05 | 0.0026 | 0.0026 mg/l |
| 25 Jun 2024, 10:35 | 0.019 | 0.019 mg/l |
| 23 May 2024, 11:10 | 0.017 | 0.017 mg/l |
| 29 Apr 2024, 11:14 | 0.0033 | 0.0033 mg/l |
| 29 Apr 2024, 11:06 | <0.03 | below 0.03 mg/l (not detected above this) |
| 15 Jan 2024, 11:31 | 0.008 | 0.008 mg/l |
| 8 Dec 2023, 11:55 | 0.0037 | 0.0037 mg/l |
| 23 Nov 2023, 13:04 | <0.002 | below 0.002 mg/l (not detected above this) |
| 18 Oct 2023, 11:19 | 0.003 | 0.003 mg/l |
Nitrate
as nitrogen (N) · code 0117 · mg/l
0.477 mg/l
Sampled 7 Jul 2026, 3 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 Jul 2026, 11:18 | 0.477 | 0.477 mg/l |
| 17 Jun 2026, 12:13 | 0.516 | 0.516 mg/l |
| 5 May 2026, 12:24 | 0.458 | 0.458 mg/l |
| 10 Mar 2026, 10:58 | 0.569 | 0.569 mg/l |
| 18 Feb 2026, 14:07 | 0.589 | 0.589 mg/l |
| 26 Jan 2026, 10:48 | 0.679 | 0.679 mg/l |
| 18 Dec 2025, 11:36 | 0.569 | 0.569 mg/l |
| 27 Nov 2025, 11:00 | 0.659 | 0.659 mg/l |
| 3 Oct 2025, 11:46 | 0.407 | 0.407 mg/l |
| 9 Sep 2025, 10:40 | 0.549 | 0.549 mg/l |
| 12 Aug 2025, 10:31 | 0.608 | 0.608 mg/l |
| 10 Jul 2025, 10:48 | 0.657 | 0.657 mg/l |
| 23 Jun 2025, 10:21 | 0.705 | 0.705 mg/l |
| 29 May 2025, 11:28 | 0.606 | 0.606 mg/l |
| 29 May 2025, 11:27 | 0.596 | 0.596 mg/l |
| 8 Apr 2025, 10:55 | 0.578 | 0.578 mg/l |
| 24 Mar 2025, 10:49 | 0.689 | 0.689 mg/l |
| 29 Oct 2024, 13:16 | 0.509 | 0.509 mg/l |
| 18 Sep 2024, 11:05 | 0.549 | 0.549 mg/l |
| 25 Jun 2024, 10:35 | 0.727 | 0.727 mg/l |
| 23 May 2024, 11:10 | 0.578 | 0.578 mg/l |
| 29 Apr 2024, 11:14 | 0.559 | 0.559 mg/l |
| 29 Apr 2024, 11:06 | 0.616 | 0.616 mg/l |
| 15 Jan 2024, 11:31 | 0.789 | 0.789 mg/l |
| 8 Dec 2023, 11:55 | 0.699 | 0.699 mg/l |
| 23 Nov 2023, 13:04 | 0.569 | 0.569 mg/l |
| 18 Oct 2023, 11:19 | 0.539 | 0.539 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.026 mg/l
Sampled 7 Jul 2026, 3 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 Jul 2026, 11:18 | 0.026 | 0.026 mg/l |
| 17 Jun 2026, 12:13 | 0.02 | 0.02 mg/l |
| 5 May 2026, 12:24 | 0.0064 | 0.0064 mg/l |
| 10 Mar 2026, 10:58 | 0.0041 | 0.0041 mg/l |
| 18 Feb 2026, 14:07 | 0.01 | 0.01 mg/l |
| 26 Jan 2026, 10:48 | 0.009 | 0.009 mg/l |
| 18 Dec 2025, 11:36 | 0.017 | 0.017 mg/l |
| 27 Nov 2025, 11:00 | 0.01 | 0.01 mg/l |
| 3 Oct 2025, 11:46 | 0.026 | 0.026 mg/l |
| 9 Sep 2025, 10:40 | 0.028 | 0.028 mg/l |
| 12 Aug 2025, 10:31 | 0.027 | 0.027 mg/l |
| 10 Jul 2025, 10:48 | 0.029 | 0.029 mg/l |
| 23 Jun 2025, 10:21 | 0.075 | 0.075 mg/l |
| 29 May 2025, 11:28 | 0.027 | 0.027 mg/l |
| 29 May 2025, 11:27 | 0.026 | 0.026 mg/l |
| 8 Apr 2025, 10:55 | 0.005 | 0.005 mg/l |
| 24 Mar 2025, 10:49 | 0.0062 | 0.0062 mg/l |
| 29 Oct 2024, 13:16 | 0.0084 | 0.0084 mg/l |
| 18 Sep 2024, 11:05 | 0.018 | 0.018 mg/l |
| 25 Jun 2024, 10:35 | 0.11 | 0.11 mg/l |
| 23 May 2024, 11:10 | 0.013 | 0.013 mg/l |
| 29 Apr 2024, 11:14 | 0.0049 | 0.0049 mg/l |
| 29 Apr 2024, 11:06 | <0.01 | below 0.01 mg/l (not detected above this) |
| 15 Jan 2024, 11:31 | 0.012 | 0.012 mg/l |
| 8 Dec 2023, 11:55 | 0.01 | 0.01 mg/l |
| 23 Nov 2023, 13:04 | 0.0078 | 0.0078 mg/l |
| 18 Oct 2023, 11:19 | 0.012 | 0.012 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
337 µS/cm
Sampled 7 Jul 2026, 3 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 Jul 2026, 11:18 | 337 | 337 µS/cm |
| 17 Jun 2026, 12:13 | 295 | 295 µS/cm |
| 5 May 2026, 12:24 | 309 | 309 µS/cm |
| 10 Mar 2026, 10:58 | 259 | 259 µS/cm |
| 18 Feb 2026, 14:07 | 197 | 197 µS/cm |
| 26 Jan 2026, 10:48 | 210 | 210 µS/cm |
| 18 Dec 2025, 11:36 | 178 | 178 µS/cm |
| 27 Nov 2025, 11:00 | 248 | 248 µS/cm |
| 3 Oct 2025, 11:46 | 338 | 338 µS/cm |
| 9 Sep 2025, 10:40 | 360 | 360 µS/cm |
| 12 Aug 2025, 10:31 | 375 | 375 µS/cm |
| 10 Jul 2025, 10:48 | 367 | 367 µS/cm |
| 23 Jun 2025, 10:21 | 357 | 357 µS/cm |
| 29 May 2025, 11:28 | 336 | 336 µS/cm |
| 29 May 2025, 11:27 | 336 | 336 µS/cm |
| 8 Apr 2025, 10:55 | 326 | 326 µS/cm |
| 24 Mar 2025, 10:49 | 309 | 309 µS/cm |
| 29 Oct 2024, 13:16 | 267 | 267 µS/cm |
| 18 Sep 2024, 11:05 | 324 | 324 µS/cm |
| 25 Jun 2024, 10:35 | 338 | 338 µS/cm |
| 23 May 2024, 11:10 | 282 | 282 µS/cm |
| 29 Apr 2024, 11:14 | 290 | 290 µS/cm |
| 29 Apr 2024, 11:06 | 296 | 296 µS/cm |
| 15 Jan 2024, 11:31 | 288 | 288 µS/cm |
| 8 Dec 2023, 11:55 | 185 | 185 µS/cm |
| 23 Nov 2023, 13:04 | 253 | 253 µS/cm |
| 18 Oct 2023, 11:19 | 279 | 279 µS/cm |
Everything measured here
67 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 67 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 27 | Oct 2023 – Jul 2026 | 101.3% 7 Jul 2026 |
| Oxygen, Dissolved as O2 9924 | River water | 27 | Oct 2023 – Jul 2026 | 9.7 mg/l 7 Jul 2026 |
| Temperature of Water 0076 | River water | 27 | Oct 2023 – Jul 2026 | 17.3 °C 7 Jul 2026 |
| pH 0061 | River water | 27 | Oct 2023 – Jul 2026 | 8.34 7 Jul 2026 |
| Ammoniacal Nitrogen as N 0111 | River water | 27 | Oct 2023 – Jul 2026 | 0.0049 mg/l 7 Jul 2026 |
| Nitrate as N 0117 | River water | 27 | Oct 2023 – Jul 2026 | 0.477 mg/l 7 Jul 2026 |
| Orthophosphate, reactive as P 0180 | River water | 27 | Oct 2023 – Jul 2026 | 0.026 mg/l 7 Jul 2026 |
| Conductivity at 25 C 0077 | River water | 27 | Oct 2023 – Jul 2026 | 337 µS/cm 7 Jul 2026 |
| 11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (F-53B Minor) 2993 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| 2-(N-Ethylperfluorooctanesulfonamido)acetic acid (B) 2942 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| 2-(N-Ethylperfluorooctanesulfonamido)acetic acid (L) 2991 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| 2-(N-Methylperfluorooctanesulfonamido)acetic acid (B) 2943 | River water | 1 | Sep 2024 – Sep 2024 | below 0.002 µg/l 18 Sep 2024 |
| 2-(N-Methylperfluorooctanesulfonamido)acetic acid (L) 2990 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| 2H,2H,3H,3H-Perfluorooctanoic acid 2989 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| 3-Perfluoroheptylpropanoic acid 2925 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| 3:3 Fluorotelomer carboxylic acid 2926 | River water | 1 | Sep 2024 – Sep 2024 | below 0.004 µg/l 18 Sep 2024 |
| 4,8-Dioxa-3H-perfluorononanoic acid (ADONA) 2988 | River water | 1 | Sep 2024 – Sep 2024 | below 0.005 µg/l 18 Sep 2024 |
| 4:2 Fluorotelomer sulfonic acid 2987 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| 6:2 Fluorotelomer sulfonic acid 2984 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| 8:2 Fluorotelomer sulfonic acid 2983 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| 9-chlorohexadecafluoro-3-oxanonane-1-sulfonic acid 2982 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 27 | Oct 2023 – Jul 2026 | 180 mg/l 7 Jul 2026 |
| Ammonia un-ionised as N 0119 | River water | 27 | Oct 2023 – Jul 2026 | 0.00015 mg/l 7 Jul 2026 |
| BOD : 5 Day ATU 0085 | River water | 17 | Apr 2024 – May 2026 | 1.1 mg/l 5 May 2026 |
| Carbon, Organic, Dissolved as C :- {DOC} 0301 | River water | 25 | Oct 2023 – Jul 2026 | 1 mg/l 7 Jul 2026 |
| Chloride 0172 | River water | 24 | Oct 2023 – Jul 2026 | 6.7 mg/l 7 Jul 2026 |
| Flow Type 2896 | River water | 17 | Sep 2024 – Jul 2026 | Low Flow 7 Jul 2026 |
| GCMS Screen : Target Based multi-residue screening : Semi Quantitative 4994 | River water | 1 | Jun 2026 – Jun 2026 | 1 text result 17 Jun 2026 |
| Hexafluoropropylene oxide dimer acid (Gen X) 2981 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| N-Ethylperfluorooctanesulfonamide 2977 | River water | 1 | Sep 2024 – Sep 2024 | below 0.002 µg/l 18 Sep 2024 |
| N-methylperfluorooctanesulfonamide 2975 | River water | 1 | Sep 2024 – Sep 2024 | below 0.002 µg/l 18 Sep 2024 |
| Nitrite as N 0118 | River water | 27 | Oct 2023 – Jul 2026 | 0.0026 mg/l 7 Jul 2026 |
| Nitrogen, Total Oxidised as N 0116 | River water | 27 | Oct 2023 – Jul 2026 | 0.48 mg/l 7 Jul 2026 |
| Perfluoro(2-ethoxyethane)sulfonic acid 2924 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluoro(4-methoxybutanoic) acid 2923 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluoro-3,6-dioxaheptanoic acid 2922 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluoro-3-methoxypropanoic acid 2921 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluoro-4-ethylcyclohexanesulfonic acid 2973 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluorobutanesulfonic acid 2972 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| Perfluorobutanoic acid 2995 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| Perfluorobutylsulfonamide (perfluorobutane sulfonamide) 2970 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluorodecanesulfonic acid 2969 | River water | 1 | Sep 2024 – Sep 2024 | below 0.002 µg/l 18 Sep 2024 |
| Perfluorodecanoic acid 8892 | River water | 1 | Sep 2024 – Sep 2024 | below 0.002 µg/l 18 Sep 2024 |
| Perfluorododecane sulfonic acid 2968 | River water | 1 | Sep 2024 – Sep 2024 | below 0.005 µg/l 18 Sep 2024 |
| Perfluorododecanoic acid 8894 | River water | 1 | Sep 2024 – Sep 2024 | below 0.002 µg/l 18 Sep 2024 |
| Perfluoroheptanesulfonic acid 2967 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluoroheptanoic acid 8889 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| Perfluorohexanesulfonamide 2965 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluorohexanesulfonic acid (B) 2944 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluorohexanesulfonic acid (L) 2964 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluorohexanoic acid 8888 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluorononanesulfonic acid 2963 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluorononanoic acid 8891 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| Perfluorooctadecanoic acid 2962 | River water | 1 | Sep 2024 – Sep 2024 | below 0.002 µg/l 18 Sep 2024 |
| Perfluorooctanesulfonamide 2961 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| Perfluorooctanesulfonic acid (branched) 2960 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluorooctanesulfonic acid (linear) 2959 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluorooctanoic acid 8890 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluoropentanesulfonic acid 2957 | River water | 1 | Sep 2024 – Sep 2024 | below 0.0005 µg/l 18 Sep 2024 |
| Perfluoropentanoic acid 8887 | River water | 1 | Sep 2024 – Sep 2024 | below 0.001 µg/l 18 Sep 2024 |
| Perfluorotetradecanoic acid 8895 | River water | 1 | Sep 2024 – Sep 2024 | below 0.006 µg/l 18 Sep 2024 |
| Perfluorotridecanoic acid 2955 | River water | 1 | Sep 2024 – Sep 2024 | below 0.005 µg/l 18 Sep 2024 |
| Perfluoroundecane sulfonic acid 2953 | River water | 1 | Sep 2024 – Sep 2024 | below 0.004 µg/l 18 Sep 2024 |
| Perfluoroundecanoic acid 8893 | River water | 1 | Sep 2024 – Sep 2024 | below 0.002 µg/l 18 Sep 2024 |
| Phosphorus, Total as P 0348 | River water | 25 | Oct 2023 – Jul 2026 | 0.034 mg/l 7 Jul 2026 |
| Silica, reactive as SiO2 0182 | River water | 25 | Oct 2023 – Jul 2026 | 7.3 mg/l 7 Jul 2026 |
| Solids, Suspended at 105 C 0135 | River water | 7 | Dec 2025 – Jul 2026 | 4.3 mg/l 7 Jul 2026 |
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.