Chess above Chesham S/W
EA name: CHESS ABOVE CHESHAM S/W
Environment Agency sampling point TH-PCNR0012 · 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
- 14 Aug 2026, 09:4648 days ago · time as the Environment Agency records it (UK clock time; the source gives no time zone)
- Samples banked
- 31 since 13 Oct 2023 Imported periods: 1 Oct 2023 – 30 Sep 2026. Samples outside them are not shown here.
- Latest sample
- River / running surface water Environmental monitoring statutory (EU directives)
- Where
- National Grid 498034, 199626As published, to the nearest 1 m. Open in a map
- River, by its own name
- Chess
- River, by the map
- River ChessPlaced on the river its name gives, 1 m from the line.
- Next gauge downstream
- Rickmansworth On the River Chess · 12 km along the river
- Nearest gauge upstream
- Chesham On the River Chess · 3.0 km along the river
- Why it was sampled
- Environmental monitoring statutory (EU directives) (21 samples)
Monitoring (national agency policy) (10 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
88.9%
Sampled 14 Aug 2026, 48 days ago · 31 results banked
Every result (31)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Aug 2026, 09:46 | 88.9 | 88.9% |
| 8 Jul 2026, 10:10 | 100.7 | 100.7% |
| 5 Jun 2026, 09:55 | 98.4 | 98.4% |
| 6 May 2026, 09:51 | 101 | 101% |
| 7 Apr 2026, 09:29 | 100.3 | 100.3% |
| 5 Mar 2026, 09:08 | 99.4 | 99.4% |
| 11 Feb 2026, 11:53 | 97.5 | 97.5% |
| 15 Jan 2026, 09:55 | 96.6 | 96.6% |
| 5 Dec 2025, 11:24 | 98.6 | 98.6% |
| 4 Nov 2025, 10:35 | 91.7 | 91.7% |
| 15 Oct 2025, 10:36 | 97.1 | 97.1% |
| 1 Sep 2025, 12:52 | 99 | 99% |
| 8 Aug 2025, 09:49 | 96.1 | 96.1% |
| 4 Jul 2025, 10:11 | 100.7 | 100.7% |
| 12 Jun 2025, 09:56 | 102.5 | 102.5% |
| 22 May 2025, 10:40 | 102.3 | 102.3% |
| 4 Apr 2025, 09:30 | 100.4 | 100.4% |
| 18 Mar 2025, 08:54 | 97.2 | 97.2% |
| 12 Feb 2025, 10:02 | 99.5 | 99.5% |
| 24 Jan 2025, 11:26 | 96.9 | 96.9% |
| 12 Dec 2024, 09:25 | 96.8 | 96.8% |
| 18 Nov 2024, 11:58 | 94.9 | 94.9% |
| 16 Oct 2024, 11:47 | 96.8 | 96.8% |
| 30 Sep 2024, 08:55 | 92.5 | 92.5% |
| 19 Aug 2024, 12:34 | 99.3 | 99.3% |
| 26 Jul 2024, 12:58 | 100.8 | 100.8% |
| 27 Mar 2024, 10:45 | 92.3 | 92.3% |
| 20 Feb 2024, 08:47 | 96.6 | 96.6% |
| 2 Feb 2024, 11:28 | 99.3 | 99.3% |
| 5 Dec 2023, 12:16 | 94.7 | 94.7% |
| 13 Oct 2023, 13:20 | 94.5 | 94.5% |
Dissolved oxygen
as O2 · code 9924 · mg/l
8.88 mg/l
Sampled 14 Aug 2026, 48 days ago · 31 results banked
Every result (31)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Aug 2026, 09:46 | 8.88 | 8.88 mg/l |
| 8 Jul 2026, 10:10 | 10.1 | 10.1 mg/l |
| 5 Jun 2026, 09:55 | 10.4 | 10.4 mg/l |
| 6 May 2026, 09:51 | 11.3 | 11.3 mg/l |
| 7 Apr 2026, 09:29 | 11.6 | 11.6 mg/l |
| 5 Mar 2026, 09:08 | 11.6 | 11.6 mg/l |
| 11 Feb 2026, 11:53 | 11 | 11 mg/l |
| 15 Jan 2026, 09:55 | 11.1 | 11.1 mg/l |
| 5 Dec 2025, 11:24 | 11.6 | 11.6 mg/l |
| 4 Nov 2025, 10:35 | 9.86 | 9.86 mg/l |
| 15 Oct 2025, 10:36 | 10.6 | 10.6 mg/l |
| 1 Sep 2025, 12:52 | 10.2 | 10.2 mg/l |
| 8 Aug 2025, 09:49 | 9.9 | 9.9 mg/l |
| 4 Jul 2025, 10:11 | 10.5 | 10.5 mg/l |
| 12 Jun 2025, 09:56 | 10.8 | 10.8 mg/l |
| 22 May 2025, 10:40 | 11.2 | 11.2 mg/l |
| 4 Apr 2025, 09:30 | 11.3 | 11.3 mg/l |
| 18 Mar 2025, 08:54 | 11.8 | 11.8 mg/l |
| 12 Feb 2025, 10:02 | 11.8 | 11.8 mg/l |
| 24 Jan 2025, 11:26 | 11.3 | 11.3 mg/l |
| 12 Dec 2024, 09:25 | 11.3 | 11.3 mg/l |
| 18 Nov 2024, 11:58 | 10.7 | 10.7 mg/l |
| 16 Oct 2024, 11:47 | 10.2 | 10.2 mg/l |
| 30 Sep 2024, 08:55 | 9.97 | 9.97 mg/l |
| 19 Aug 2024, 12:34 | 10.3 | 10.3 mg/l |
| 26 Jul 2024, 12:58 | 10.3 | 10.3 mg/l |
| 27 Mar 2024, 10:45 | 10.5 | 10.5 mg/l |
| 20 Feb 2024, 08:47 | 11.1 | 11.1 mg/l |
| 2 Feb 2024, 11:28 | 11.3 | 11.3 mg/l |
| 5 Dec 2023, 12:16 | 11.1 | 11.1 mg/l |
| 13 Oct 2023, 13:20 | 9.53 | 9.53 mg/l |
Water temperature
code 0076 · °C
15.3 °C
Sampled 14 Aug 2026, 48 days ago · 31 results banked
Every result (31)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Aug 2026, 09:46 | 15.3 | 15.3 °C |
| 8 Jul 2026, 10:10 | 15.2 | 15.2 °C |
| 5 Jun 2026, 09:55 | 12.6 | 12.6 °C |
| 6 May 2026, 09:51 | 10.4 | 10.4 °C |
| 7 Apr 2026, 09:29 | 9 | 9 °C |
| 5 Mar 2026, 09:08 | 8.6 | 8.6 °C |
| 11 Feb 2026, 11:53 | 10.1 | 10.1 °C |
| 15 Jan 2026, 09:55 | 9.3 | 9.3 °C |
| 5 Dec 2025, 11:24 | 8.2 | 8.2 °C |
| 4 Nov 2025, 10:35 | 12 | 12 °C |
| 15 Oct 2025, 10:36 | 11.4 | 11.4 °C |
| 1 Sep 2025, 12:52 | 13.8 | 13.8 °C |
| 8 Aug 2025, 09:49 | 13.9 | 13.9 °C |
| 4 Jul 2025, 10:11 | 13.5 | 13.5 °C |
| 12 Jun 2025, 09:56 | 13 | 13 °C |
| 22 May 2025, 10:40 | 11.2 | 11.2 °C |
| 4 Apr 2025, 09:30 | 10.2 | 10.2 °C |
| 18 Mar 2025, 08:54 | 7 | 7 °C |
| 12 Feb 2025, 10:02 | 8 | 8 °C |
| 24 Jan 2025, 11:26 | 8.6 | 8.6 °C |
| 12 Dec 2024, 09:25 | 8.4 | 8.4 °C |
| 18 Nov 2024, 11:58 | 9.8 | 9.8 °C |
| 16 Oct 2024, 11:47 | 12.8 | 12.8 °C |
| 30 Sep 2024, 08:55 | 11.9 | 11.9 °C |
| 19 Aug 2024, 12:34 | 13.7 | 13.7 °C |
| 26 Jul 2024, 12:58 | 14.4 | 14.4 °C |
| 27 Mar 2024, 10:45 | 9.4 | 9.4 °C |
| 20 Feb 2024, 08:47 | 9 | 9 °C |
| 2 Feb 2024, 11:28 | 9.4 | 9.4 °C |
| 5 Dec 2023, 12:16 | 8.3 | 8.3 °C |
| 13 Oct 2023, 13:20 | 14.9 | 14.9 °C |
pH
code 0061
7.88
Sampled 14 Aug 2026, 48 days ago · 31 results banked
Every result (31)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Aug 2026, 09:46 | 7.88 | 7.88 |
| 8 Jul 2026, 10:10 | 7.91 | 7.91 |
| 5 Jun 2026, 09:55 | 7.92 | 7.92 |
| 6 May 2026, 09:51 | 7.98 | 7.98 |
| 7 Apr 2026, 09:29 | 7.91 | 7.91 |
| 5 Mar 2026, 09:08 | 8.18 | 8.18 |
| 11 Feb 2026, 11:53 | 7.94 | 7.94 |
| 15 Jan 2026, 09:55 | 8.06 | 8.06 |
| 5 Dec 2025, 11:24 | 7.92 | 7.92 |
| 4 Nov 2025, 10:35 | 7.79 | 7.79 |
| 15 Oct 2025, 10:36 | 8.04 | 8.04 |
| 1 Sep 2025, 12:52 | 8.17 | 8.17 |
| 8 Aug 2025, 09:49 | 8.05 | 8.05 |
| 4 Jul 2025, 10:11 | 8.03 | 8.03 |
| 12 Jun 2025, 09:56 | 8.03 | 8.03 |
| 22 May 2025, 10:40 | 7.99 | 7.99 |
| 4 Apr 2025, 09:30 | 7.95 | 7.95 |
| 18 Mar 2025, 08:54 | 8.1 | 8.1 |
| 12 Feb 2025, 10:02 | 7.98 | 7.98 |
| 24 Jan 2025, 11:26 | 7.96 | 7.96 |
| 12 Dec 2024, 09:25 | 8.08 | 8.08 |
| 18 Nov 2024, 11:58 | 7.81 | 7.81 |
| 16 Oct 2024, 11:47 | 7.78 | 7.78 |
| 30 Sep 2024, 08:55 | 7.73 | 7.73 |
| 19 Aug 2024, 12:34 | 8.07 | 8.07 |
| 26 Jul 2024, 12:58 | 8.12 | 8.12 |
| 27 Mar 2024, 10:45 | 7.51 | 7.51 |
| 20 Feb 2024, 08:47 | 7.76 | 7.76 |
| 2 Feb 2024, 11:28 | 8.14 | 8.14 |
| 5 Dec 2023, 12:16 | 7.88 | 7.88 |
| 13 Oct 2023, 13:20 | 7.92 | 7.92 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
below 0.03 mg/l (not detected above this)
Sampled 14 Aug 2026, 48 days ago · 31 results banked
Every result (31)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Aug 2026, 09:46 | <0.03 | below 0.03 mg/l (not detected above this) |
| 8 Jul 2026, 10:10 | <0.03 | below 0.03 mg/l (not detected above this) |
| 5 Jun 2026, 09:55 | <0.03 | below 0.03 mg/l (not detected above this) |
| 6 May 2026, 09:51 | <0.03 | below 0.03 mg/l (not detected above this) |
| 7 Apr 2026, 09:29 | <0.03 | below 0.03 mg/l (not detected above this) |
| 5 Mar 2026, 09:08 | <0.03 | below 0.03 mg/l (not detected above this) |
| 11 Feb 2026, 11:53 | <0.03 | below 0.03 mg/l (not detected above this) |
| 15 Jan 2026, 09:55 | <0.03 | below 0.03 mg/l (not detected above this) |
| 5 Dec 2025, 11:24 | 0.03 | 0.03 mg/l |
| 4 Nov 2025, 10:35 | <0.03 | below 0.03 mg/l (not detected above this) |
| 15 Oct 2025, 10:36 | <0.03 | below 0.03 mg/l (not detected above this) |
| 1 Sep 2025, 12:52 | <0.03 | below 0.03 mg/l (not detected above this) |
| 8 Aug 2025, 09:49 | <0.03 | below 0.03 mg/l (not detected above this) |
| 4 Jul 2025, 10:11 | <0.03 | below 0.03 mg/l (not detected above this) |
| 12 Jun 2025, 09:56 | <0.03 | below 0.03 mg/l (not detected above this) |
| 22 May 2025, 10:40 | <0.03 | below 0.03 mg/l (not detected above this) |
| 4 Apr 2025, 09:30 | <0.03 | below 0.03 mg/l (not detected above this) |
| 18 Mar 2025, 08:54 | <0.03 | below 0.03 mg/l (not detected above this) |
| 12 Feb 2025, 10:02 | <0.03 | below 0.03 mg/l (not detected above this) |
| 24 Jan 2025, 11:26 | 0.064 | 0.064 mg/l |
| 12 Dec 2024, 09:25 | <0.03 | below 0.03 mg/l (not detected above this) |
| 18 Nov 2024, 11:58 | <0.03 | below 0.03 mg/l (not detected above this) |
| 16 Oct 2024, 11:47 | <0.03 | below 0.03 mg/l (not detected above this) |
| 30 Sep 2024, 08:55 | <0.03 | below 0.03 mg/l (not detected above this) |
| 19 Aug 2024, 12:34 | <0.03 | below 0.03 mg/l (not detected above this) |
| 26 Jul 2024, 12:58 | <0.03 | below 0.03 mg/l (not detected above this) |
| 27 Mar 2024, 10:45 | 0.061 | 0.061 mg/l |
| 20 Feb 2024, 08:47 | 0.049 | 0.049 mg/l |
| 2 Feb 2024, 11:28 | <0.03 | below 0.03 mg/l (not detected above this) |
| 5 Dec 2023, 12:16 | <0.03 | below 0.03 mg/l (not detected above this) |
| 13 Oct 2023, 13:20 | <0.03 | below 0.03 mg/l (not detected above this) |
Nitrate
as nitrogen (N) · code 0117 · mg/l
4.39 mg/l
Sampled 14 Aug 2026, 48 days ago · 31 results banked
Every result (31)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Aug 2026, 09:46 | 4.39 | 4.39 mg/l |
| 8 Jul 2026, 10:10 | 4.49 | 4.49 mg/l |
| 5 Jun 2026, 09:55 | 4.69 | 4.69 mg/l |
| 6 May 2026, 09:51 | 4.89 | 4.89 mg/l |
| 7 Apr 2026, 09:29 | 5 | 5 mg/l |
| 5 Mar 2026, 09:08 | 5.3 | 5.3 mg/l |
| 11 Feb 2026, 11:53 | 4.99 | 4.99 mg/l |
| 15 Jan 2026, 09:55 | 4.79 | 4.79 mg/l |
| 5 Dec 2025, 11:24 | 4.69 | 4.69 mg/l |
| 4 Nov 2025, 10:35 | 4.48 | 4.48 mg/l |
| 15 Oct 2025, 10:36 | 4.59 | 4.59 mg/l |
| 1 Sep 2025, 12:52 | 4.49 | 4.49 mg/l |
| 8 Aug 2025, 09:49 | 4.59 | 4.59 mg/l |
| 4 Jul 2025, 10:11 | 4.69 | 4.69 mg/l |
| 12 Jun 2025, 09:56 | 4.79 | 4.79 mg/l |
| 22 May 2025, 10:40 | 4.79 | 4.79 mg/l |
| 4 Apr 2025, 09:30 | 5.5 | 5.5 mg/l |
| 18 Mar 2025, 08:54 | 5.6 | 5.6 mg/l |
| 12 Feb 2025, 10:02 | 5.59 | 5.59 mg/l |
| 24 Jan 2025, 11:26 | 4.19 | 4.19 mg/l |
| 12 Dec 2024, 09:25 | 4.99 | 4.99 mg/l |
| 18 Nov 2024, 11:58 | 5.09 | 5.09 mg/l |
| 16 Oct 2024, 11:47 | 4.89 | 4.89 mg/l |
| 30 Sep 2024, 08:55 | 3.09 | 3.09 mg/l |
| 19 Aug 2024, 12:34 | 4.59 | 4.59 mg/l |
| 26 Jul 2024, 12:58 | 5.09 | 5.09 mg/l |
| 27 Mar 2024, 10:45 | 5.39 | 5.39 mg/l |
| 20 Feb 2024, 08:47 | 5.49 | 5.49 mg/l |
| 2 Feb 2024, 11:28 | 4.99 | 4.99 mg/l |
| 5 Dec 2023, 12:16 | 4.19 | 4.19 mg/l |
| 13 Oct 2023, 13:20 | 3.09 | 3.09 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.053 mg/l
Sampled 14 Aug 2026, 48 days ago · 31 results banked
Every result (31)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Aug 2026, 09:46 | 0.053 | 0.053 mg/l |
| 8 Jul 2026, 10:10 | 0.049 | 0.049 mg/l |
| 5 Jun 2026, 09:55 | 0.052 | 0.052 mg/l |
| 6 May 2026, 09:51 | 0.035 | 0.035 mg/l |
| 7 Apr 2026, 09:29 | 0.049 | 0.049 mg/l |
| 5 Mar 2026, 09:08 | 0.05 | 0.05 mg/l |
| 11 Feb 2026, 11:53 | 0.051 | 0.051 mg/l |
| 15 Jan 2026, 09:55 | 0.061 | 0.061 mg/l |
| 5 Dec 2025, 11:24 | 0.067 | 0.067 mg/l |
| 4 Nov 2025, 10:35 | 0.055 | 0.055 mg/l |
| 15 Oct 2025, 10:36 | 0.05 | 0.05 mg/l |
| 1 Sep 2025, 12:52 | 0.049 | 0.049 mg/l |
| 8 Aug 2025, 09:49 | 0.047 | 0.047 mg/l |
| 4 Jul 2025, 10:11 | 0.045 | 0.045 mg/l |
| 12 Jun 2025, 09:56 | 0.045 | 0.045 mg/l |
| 22 May 2025, 10:40 | 0.039 | 0.039 mg/l |
| 4 Apr 2025, 09:30 | 0.033 | 0.033 mg/l |
| 18 Mar 2025, 08:54 | 0.036 | 0.036 mg/l |
| 12 Feb 2025, 10:02 | 0.046 | 0.046 mg/l |
| 24 Jan 2025, 11:26 | 0.056 | 0.056 mg/l |
| 12 Dec 2024, 09:25 | 0.047 | 0.047 mg/l |
| 18 Nov 2024, 11:58 | 0.05 | 0.05 mg/l |
| 16 Oct 2024, 11:47 | 0.051 | 0.051 mg/l |
| 30 Sep 2024, 08:55 | 0.057 | 0.057 mg/l |
| 19 Aug 2024, 12:34 | 0.042 | 0.042 mg/l |
| 26 Jul 2024, 12:58 | 0.044 | 0.044 mg/l |
| 27 Mar 2024, 10:45 | 0.049 | 0.049 mg/l |
| 20 Feb 2024, 08:47 | 0.06 | 0.06 mg/l |
| 2 Feb 2024, 11:28 | 0.049 | 0.049 mg/l |
| 5 Dec 2023, 12:16 | 0.066 | 0.066 mg/l |
| 13 Oct 2023, 13:20 | 0.092 | 0.092 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
609 µS/cm
Sampled 14 Aug 2026, 48 days ago · 31 results banked
Every result (31)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Aug 2026, 09:46 | 609 | 609 µS/cm |
| 8 Jul 2026, 10:10 | 584 | 584 µS/cm |
| 5 Jun 2026, 09:55 | 589 | 589 µS/cm |
| 6 May 2026, 09:51 | 584 | 584 µS/cm |
| 7 Apr 2026, 09:29 | 610 | 610 µS/cm |
| 5 Mar 2026, 09:08 | 598 | 598 µS/cm |
| 11 Feb 2026, 11:53 | 579 | 579 µS/cm |
| 15 Jan 2026, 09:55 | 654 | 654 µS/cm |
| 5 Dec 2025, 11:24 | 610 | 610 µS/cm |
| 4 Nov 2025, 10:35 | 566 | 566 µS/cm |
| 15 Oct 2025, 10:36 | 587 | 587 µS/cm |
| 1 Sep 2025, 12:52 | 583 | 583 µS/cm |
| 8 Aug 2025, 09:49 | 584 | 584 µS/cm |
| 4 Jul 2025, 10:11 | 590 | 590 µS/cm |
| 12 Jun 2025, 09:56 | 583 | 583 µS/cm |
| 22 May 2025, 10:40 | 583 | 583 µS/cm |
| 4 Apr 2025, 09:30 | 592 | 592 µS/cm |
| 18 Mar 2025, 08:54 | 591 | 591 µS/cm |
| 12 Feb 2025, 10:02 | 593 | 593 µS/cm |
| 24 Jan 2025, 11:26 | 682 | 682 µS/cm |
| 12 Dec 2024, 09:25 | 572 | 572 µS/cm |
| 18 Nov 2024, 11:58 | 592 | 592 µS/cm |
| 16 Oct 2024, 11:47 | 555 | 555 µS/cm |
| 30 Sep 2024, 08:55 | 424 | 424 µS/cm |
| 19 Aug 2024, 12:34 | 580 | 580 µS/cm |
| 26 Jul 2024, 12:58 | 590 | 590 µS/cm |
| 27 Mar 2024, 10:45 | 583 | 583 µS/cm |
| 20 Feb 2024, 08:47 | 588 | 588 µS/cm |
| 2 Feb 2024, 11:28 | 587 | 587 µS/cm |
| 5 Dec 2023, 12:16 | 574 | 574 µS/cm |
| 13 Oct 2023, 13:20 | 470 | 470 µS/cm |
Everything measured here
60 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 60 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 31 | Oct 2023 – Aug 2026 | 88.9% 14 Aug 2026 |
| Oxygen, Dissolved as O2 9924 | River water | 31 | Oct 2023 – Aug 2026 | 8.88 mg/l 14 Aug 2026 |
| Temperature of Water 0076 | River water | 31 | Oct 2023 – Aug 2026 | 15.3 °C 14 Aug 2026 |
| pH 0061 | River water | 31 | Oct 2023 – Aug 2026 | 7.88 14 Aug 2026 |
| Ammoniacal Nitrogen as N 0111 | River water | 31 | Oct 2023 – Aug 2026 | below 0.03 mg/l 14 Aug 2026 |
| Nitrate as N 0117 | River water | 31 | Oct 2023 – Aug 2026 | 4.39 mg/l 14 Aug 2026 |
| Orthophosphate, reactive as P 0180 | River water | 31 | Oct 2023 – Aug 2026 | 0.053 mg/l 14 Aug 2026 |
| Conductivity at 25 C 0077 | River water | 31 | Oct 2023 – Aug 2026 | 609 µS/cm 14 Aug 2026 |
| 11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (F-53B Minor) 2993 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| 2-(N-Ethylperfluorooctanesulfonamido)acetic acid (B) 2942 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| 2-(N-Ethylperfluorooctanesulfonamido)acetic acid (L) 2991 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| 2-(N-Methylperfluorooctanesulfonamido)acetic acid (B) 2943 | River water | 3 | Oct 2023 – Feb 2025 | below 0.002 µg/l 12 Feb 2025 |
| 2-(N-Methylperfluorooctanesulfonamido)acetic acid (L) 2990 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| 2H,2H,3H,3H-Perfluorooctanoic acid 2989 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| 3-Perfluoroheptylpropanoic acid 2925 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| 3:3 Fluorotelomer carboxylic acid 2926 | River water | 3 | Oct 2023 – Feb 2025 | below 0.004 µg/l 12 Feb 2025 |
| 4,8-Dioxa-3H-perfluorononanoic acid (ADONA) 2988 | River water | 3 | Oct 2023 – Feb 2025 | below 0.005 µg/l 12 Feb 2025 |
| 4:2 Fluorotelomer sulfonic acid 2987 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| 6:2 Fluorotelomer sulfonic acid 2984 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| 8:2 Fluorotelomer sulfonic acid 2983 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| 9-chlorohexadecafluoro-3-oxanonane-1-sulfonic acid 2982 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 31 | Oct 2023 – Aug 2026 | 260 mg/l 14 Aug 2026 |
| Ammonia un-ionised as N 0119 | River water | 31 | Oct 2023 – Aug 2026 | below 0.00061 mg/l 14 Aug 2026 |
| BOD : 5 Day ATU 0085 | River water | 27 | Feb 2024 – Aug 2026 | below 3 mg/l 14 Aug 2026 |
| Hexafluoropropylene oxide dimer acid (Gen X) 2981 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| N-Ethylperfluorooctanesulfonamide 2977 | River water | 3 | Oct 2023 – Feb 2025 | below 0.002 µg/l 12 Feb 2025 |
| N-methylperfluorooctanesulfonamide 2975 | River water | 3 | Oct 2023 – Feb 2025 | below 0.002 µg/l 12 Feb 2025 |
| Nitrite as N 0118 | River water | 31 | Oct 2023 – Aug 2026 | 0.012 mg/l 14 Aug 2026 |
| Nitrogen, Total Oxidised as N 0116 | River water | 31 | Oct 2023 – Aug 2026 | 4.4 mg/l 14 Aug 2026 |
| Perfluoro(2-ethoxyethane)sulfonic acid 2924 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluoro(4-methoxybutanoic) acid 2923 | River water | 2 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluoro-3,6-dioxaheptanoic acid 2922 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluoro-3-methoxypropanoic acid 2921 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluoro-4-ethylcyclohexanesulfonic acid 2973 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluorobutanesulfonic acid 2972 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| Perfluorobutanoic acid 2995 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| Perfluorobutylsulfonamide (perfluorobutane sulfonamide) 2970 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluorodecanesulfonic acid 2969 | River water | 3 | Oct 2023 – Feb 2025 | below 0.002 µg/l 12 Feb 2025 |
| Perfluorodecanoic acid 8892 | River water | 3 | Oct 2023 – Feb 2025 | below 0.002 µg/l 12 Feb 2025 |
| Perfluorododecane sulfonic acid 2968 | River water | 3 | Oct 2023 – Feb 2025 | below 0.005 µg/l 12 Feb 2025 |
| Perfluorododecanoic acid 8894 | River water | 3 | Oct 2023 – Feb 2025 | below 0.002 µg/l 12 Feb 2025 |
| Perfluoroheptanesulfonic acid 2967 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluoroheptanoic acid 8889 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| Perfluorohexanesulfonamide 2965 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluorohexanesulfonic acid (B) 2944 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluorohexanesulfonic acid (L) 2964 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluorohexanoic acid 8888 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluorononanesulfonic acid 2963 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluorononanoic acid 8891 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| Perfluorooctadecanoic acid 2962 | River water | 3 | Oct 2023 – Feb 2025 | below 0.002 µg/l 12 Feb 2025 |
| Perfluorooctanesulfonamide 2961 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| Perfluorooctanesulfonic acid (branched) 2960 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluorooctanesulfonic acid (linear) 2959 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluorooctanoic acid 8890 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluoropentanesulfonic acid 2957 | River water | 3 | Oct 2023 – Feb 2025 | below 0.0005 µg/l 12 Feb 2025 |
| Perfluoropentanoic acid 8887 | River water | 3 | Oct 2023 – Feb 2025 | below 0.001 µg/l 12 Feb 2025 |
| Perfluorotetradecanoic acid 8895 | River water | 2 | Feb 2024 – Feb 2025 | below 0.006 µg/l 12 Feb 2025 |
| Perfluorotridecanoic acid 2955 | River water | 3 | Oct 2023 – Feb 2025 | below 0.005 µg/l 12 Feb 2025 |
| Perfluoroundecane sulfonic acid 2953 | River water | 3 | Oct 2023 – Feb 2025 | below 0.004 µg/l 12 Feb 2025 |
| Perfluoroundecanoic acid 8893 | River water | 3 | Oct 2023 – Feb 2025 | below 0.002 µg/l 12 Feb 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.