Gwash
EA name: GWASH (also listed as “GWASH U/S KNOSSINGTON STW”)
Environment Agency sampling point AN-GWASKNOS · 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 May 2026, 09:535 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
- 22 since 16 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 480638, 307809As published, to the nearest 1 m. Open in a map
- River, by its own name
- Gwash
- River, by the map
- Not placedNearest line is 70 m away and its name does not agree. The river map cannot say which watercourse this is.
- Next gauge downstream
- Not known
- Why it was sampled
- Monitoring (national agency policy) (22 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
94.1%
Sampled 7 May 2026, 5 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 May 2026, 09:53 | 94.1 | 94.1% |
| 22 Apr 2026, 12:17 | 104.7 | 104.7% |
| 20 Mar 2026, 09:52 | 101.2 | 101.2% |
| 16 Feb 2026, 12:41 | 98.4 | 98.4% |
| 16 Jan 2026, 09:46 | 98.9 | 98.9% |
| 14 Mar 2025, 12:39 | 99 | 99% |
| 7 Feb 2025, 13:11 | 98.7 | 98.7% |
| 21 Jan 2025, 12:39 | 98.1 | 98.1% |
| 9 Dec 2024, 12:26 | 98.1 | 98.1% |
| 18 Nov 2024, 10:30 | 97.3 | 97.3% |
| 21 Oct 2024, 12:12 | 98.3 | 98.3% |
| 16 Sep 2024, 11:04 | 95.5 | 95.5% |
| 29 Aug 2024, 10:43 | 85.8 | 85.8% |
| 22 Jul 2024, 11:13 | 92 | 92% |
| 20 May 2024, 13:47 | 102 | 102% |
| 15 Apr 2024, 11:04 | 98.5 | 98.5% |
| 18 Mar 2024, 09:45 | 98.4 | 98.4% |
| 21 Feb 2024, 11:54 | 98.1 | 98.1% |
| 15 Jan 2024, 10:04 | 98 | 98% |
| 6 Dec 2023, 09:38 | 93.7 | 93.7% |
| 20 Nov 2023, 10:12 | 93.4 | 93.4% |
| 16 Oct 2023, 10:39 | 94.5 | 94.5% |
Dissolved oxygen
as O2 · code 9924 · mg/l
10.8 mg/l
Sampled 7 May 2026, 5 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 May 2026, 09:53 | 10.8 | 10.8 mg/l |
| 22 Apr 2026, 12:17 | 11.7 | 11.7 mg/l |
| 20 Mar 2026, 09:52 | 12 | 12 mg/l |
| 16 Feb 2026, 12:41 | 12.4 | 12.4 mg/l |
| 16 Jan 2026, 09:46 | 12.7 | 12.7 mg/l |
| 14 Mar 2025, 12:39 | 12.5 | 12.5 mg/l |
| 7 Feb 2025, 13:11 | 13 | 13 mg/l |
| 21 Jan 2025, 12:39 | 12.6 | 12.6 mg/l |
| 9 Dec 2024, 12:26 | 11.9 | 11.9 mg/l |
| 18 Nov 2024, 10:30 | 12.1 | 12.1 mg/l |
| 21 Oct 2024, 12:12 | 10.7 | 10.7 mg/l |
| 16 Sep 2024, 11:04 | 10.3 | 10.3 mg/l |
| 29 Aug 2024, 10:43 | 8.74 | 8.74 mg/l |
| 22 Jul 2024, 11:13 | 9.13 | 9.13 mg/l |
| 20 May 2024, 13:47 | 10.2 | 10.2 mg/l |
| 15 Apr 2024, 11:04 | 11.4 | 11.4 mg/l |
| 18 Mar 2024, 09:45 | 11.4 | 11.4 mg/l |
| 21 Feb 2024, 11:54 | 11.5 | 11.5 mg/l |
| 15 Jan 2024, 10:04 | 13.6 | 13.6 mg/l |
| 6 Dec 2023, 09:38 | 12.1 | 12.1 mg/l |
| 20 Nov 2023, 10:12 | 10.8 | 10.8 mg/l |
| 16 Oct 2023, 10:39 | 11.3 | 11.3 mg/l |
Water temperature
code 0076 · °C
9.2 °C
Sampled 7 May 2026, 5 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 May 2026, 09:53 | 9.2 | 9.2 °C |
| 22 Apr 2026, 12:17 | 10.4 | 10.4 °C |
| 20 Mar 2026, 09:52 | 7.9 | 7.9 °C |
| 16 Feb 2026, 12:41 | 5.6 | 5.6 °C |
| 16 Jan 2026, 09:46 | 4.6 | 4.6 °C |
| 14 Mar 2025, 12:39 | 5.4 | 5.4 °C |
| 7 Feb 2025, 13:11 | 3.7 | 3.7 °C |
| 21 Jan 2025, 12:39 | 4.7 | 4.7 °C |
| 9 Dec 2024, 12:26 | 6.9 | 6.9 °C |
| 18 Nov 2024, 10:30 | 6.1 | 6.1 °C |
| 21 Oct 2024, 12:12 | 11.5 | 11.5 °C |
| 16 Sep 2024, 11:04 | 11.9 | 11.9 °C |
| 29 Aug 2024, 10:43 | 14.4 | 14.4 °C |
| 22 Jul 2024, 11:13 | 15.6 | 15.6 °C |
| 20 May 2024, 13:47 | 15.3 | 15.3 °C |
| 15 Apr 2024, 11:04 | 8.7 | 8.7 °C |
| 18 Mar 2024, 09:45 | 9 | 9 °C |
| 21 Feb 2024, 11:54 | 8.4 | 8.4 °C |
| 15 Jan 2024, 10:04 | 1.7 | 1.7 °C |
| 6 Dec 2023, 09:38 | 4.4 | 4.4 °C |
| 20 Nov 2023, 10:12 | 9 | 9 °C |
| 16 Oct 2023, 10:39 | 7.5 | 7.5 °C |
pH
code 0061
8.1
Sampled 7 May 2026, 5 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 May 2026, 09:53 | 8.1 | 8.1 |
| 22 Apr 2026, 12:17 | 8.2 | 8.2 |
| 20 Mar 2026, 09:52 | 8.29 | 8.29 |
| 16 Feb 2026, 12:41 | 8.14 | 8.14 |
| 16 Jan 2026, 09:46 | 7.92 | 7.92 |
| 14 Mar 2025, 12:39 | 8.49 | 8.49 |
| 7 Feb 2025, 13:11 | 8.25 | 8.25 |
| 21 Jan 2025, 12:39 | 8.24 | 8.24 |
| 9 Dec 2024, 12:26 | 7.96 | 7.96 |
| 18 Nov 2024, 10:30 | 8.34 | 8.34 |
| 21 Oct 2024, 12:12 | 8.02 | 8.02 |
| 16 Sep 2024, 11:04 | 8 | 8 |
| 29 Aug 2024, 10:43 | 7.99 | 7.99 |
| 22 Jul 2024, 11:13 | 8.05 | 8.05 |
| 20 May 2024, 13:47 | 8.21 | 8.21 |
| 15 Apr 2024, 11:04 | 8.2 | 8.2 |
| 18 Mar 2024, 09:45 | 8 | 8 |
| 21 Feb 2024, 11:54 | 7.93 | 7.93 |
| 15 Jan 2024, 10:04 | 8.21 | 8.21 |
| 6 Dec 2023, 09:38 | 7.97 | 7.97 |
| 20 Nov 2023, 10:12 | 8.04 | 8.04 |
| 16 Oct 2023, 10:39 | 8.07 | 8.07 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
below 0.03 mg/l (not detected above this)
Sampled 7 May 2026, 5 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 May 2026, 09:53 | <0.03 | below 0.03 mg/l (not detected above this) |
| 22 Apr 2026, 12:17 | 0.2 | 0.2 mg/l |
| 20 Mar 2026, 09:52 | 0.14 | 0.14 mg/l |
| 16 Feb 2026, 12:41 | <0.03 | below 0.03 mg/l (not detected above this) |
| 16 Jan 2026, 09:46 | <0.03 | below 0.03 mg/l (not detected above this) |
| 14 Mar 2025, 12:39 | 0.11 | 0.11 mg/l |
| 7 Feb 2025, 13:11 | <0.03 | below 0.03 mg/l (not detected above this) |
| 21 Jan 2025, 12:39 | 0.044 | 0.044 mg/l |
| 9 Dec 2024, 12:26 | <0.03 | below 0.03 mg/l (not detected above this) |
| 18 Nov 2024, 10:30 | 0.072 | 0.072 mg/l |
| 21 Oct 2024, 12:12 | <0.03 | below 0.03 mg/l (not detected above this) |
| 16 Sep 2024, 11:04 | <0.03 | below 0.03 mg/l (not detected above this) |
| 29 Aug 2024, 10:43 | 0.061 | 0.061 mg/l |
| 22 Jul 2024, 11:13 | 0.047 | 0.047 mg/l |
| 20 May 2024, 13:47 | 0.055 | 0.055 mg/l |
| 15 Apr 2024, 11:04 | 0.059 | 0.059 mg/l |
| 18 Mar 2024, 09:45 | 0.043 | 0.043 mg/l |
| 21 Feb 2024, 11:54 | 0.046 | 0.046 mg/l |
| 15 Jan 2024, 10:04 | 0.095 | 0.095 mg/l |
| 6 Dec 2023, 09:38 | 0.038 | 0.038 mg/l |
| 20 Nov 2023, 10:12 | 0.03 | 0.03 mg/l |
| 16 Oct 2023, 10:39 | 0.11 | 0.11 mg/l |
Nitrate
as nitrogen (N) · code 0117 · mg/l
0.303 mg/l
Sampled 7 May 2026, 5 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 May 2026, 09:53 | 0.303 | 0.303 mg/l |
| 22 Apr 2026, 12:17 | 0.348 | 0.348 mg/l |
| 20 Mar 2026, 09:52 | 0.747 | 0.747 mg/l |
| 16 Feb 2026, 12:41 | 1.3 | 1.3 mg/l |
| 16 Jan 2026, 09:46 | 1.8 | 1.8 mg/l |
| 14 Mar 2025, 12:39 | 0.641 | 0.641 mg/l |
| 7 Feb 2025, 13:11 | 1.1 | 1.1 mg/l |
| 21 Jan 2025, 12:39 | 1.29 | 1.29 mg/l |
| 9 Dec 2024, 12:26 | 1.49 | 1.49 mg/l |
| 18 Nov 2024, 10:30 | 0.337 | 0.337 mg/l |
| 21 Oct 2024, 12:12 | 0.546 | 0.546 mg/l |
| 16 Sep 2024, 11:04 | 0.189 | 0.189 mg/l |
| 29 Aug 2024, 10:43 | 0.173 | 0.173 mg/l |
| 22 Jul 2024, 11:13 | 0.191 | 0.191 mg/l |
| 20 May 2024, 13:47 | 0.519 | 0.519 mg/l |
| 15 Apr 2024, 11:04 | 0.677 | 0.677 mg/l |
| 18 Mar 2024, 09:45 | 0.989 | 0.989 mg/l |
| 21 Feb 2024, 11:54 | 0.852 | 0.852 mg/l |
| 15 Jan 2024, 10:04 | 1.79 | 1.79 mg/l |
| 6 Dec 2023, 09:38 | 2.09 | 2.09 mg/l |
| 20 Nov 2023, 10:12 | 1.08 | 1.08 mg/l |
| 16 Oct 2023, 10:39 | 0.96 | 0.96 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.049 mg/l
Sampled 7 May 2026, 5 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 May 2026, 09:53 | 0.049 | 0.049 mg/l |
| 22 Apr 2026, 12:17 | 0.042 | 0.042 mg/l |
| 20 Mar 2026, 09:52 | 0.046 | 0.046 mg/l |
| 16 Feb 2026, 12:41 | 0.041 | 0.041 mg/l |
| 16 Jan 2026, 09:46 | 0.071 | 0.071 mg/l |
| 14 Mar 2025, 12:39 | 0.031 | 0.031 mg/l |
| 7 Feb 2025, 13:11 | 0.023 | 0.023 mg/l |
| 21 Jan 2025, 12:39 | 0.031 | 0.031 mg/l |
| 9 Dec 2024, 12:26 | 0.072 | 0.072 mg/l |
| 18 Nov 2024, 10:30 | 0.049 | 0.049 mg/l |
| 21 Oct 2024, 12:12 | 0.039 | 0.039 mg/l |
| 16 Sep 2024, 11:04 | 0.07 | 0.07 mg/l |
| 29 Aug 2024, 10:43 | 0.052 | 0.052 mg/l |
| 22 Jul 2024, 11:13 | 0.099 | 0.099 mg/l |
| 20 May 2024, 13:47 | 0.091 | 0.091 mg/l |
| 15 Apr 2024, 11:04 | 0.054 | 0.054 mg/l |
| 18 Mar 2024, 09:45 | 0.034 | 0.034 mg/l |
| 21 Feb 2024, 11:54 | 0.045 | 0.045 mg/l |
| 15 Jan 2024, 10:04 | 0.036 | 0.036 mg/l |
| 6 Dec 2023, 09:38 | 0.043 | 0.043 mg/l |
| 20 Nov 2023, 10:12 | 0.059 | 0.059 mg/l |
| 16 Oct 2023, 10:39 | 0.059 | 0.059 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
515 µS/cm
Sampled 7 May 2026, 5 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 May 2026, 09:53 | 515 | 515 µS/cm |
| 22 Apr 2026, 12:17 | 541 | 541 µS/cm |
| 20 Mar 2026, 09:52 | 562 | 562 µS/cm |
| 16 Feb 2026, 12:41 | 398 | 398 µS/cm |
| 16 Jan 2026, 09:46 | 366 | 366 µS/cm |
| 14 Mar 2025, 12:39 | 616 | 616 µS/cm |
| 7 Feb 2025, 13:11 | 642 | 642 µS/cm |
| 21 Jan 2025, 12:39 | 665 | 665 µS/cm |
| 9 Dec 2024, 12:26 | 393 | 393 µS/cm |
| 18 Nov 2024, 10:30 | 636 | 636 µS/cm |
| 21 Oct 2024, 12:12 | 477 | 477 µS/cm |
| 16 Sep 2024, 11:04 | 489 | 489 µS/cm |
| 29 Aug 2024, 10:43 | 535 | 535 µS/cm |
| 22 Jul 2024, 11:13 | 480 | 480 µS/cm |
| 20 May 2024, 13:47 | 562 | 562 µS/cm |
| 15 Apr 2024, 11:04 | 533 | 533 µS/cm |
| 18 Mar 2024, 09:45 | 472 | 472 µS/cm |
| 21 Feb 2024, 11:54 | 345 | 345 µS/cm |
| 15 Jan 2024, 10:04 | 661 | 661 µS/cm |
| 6 Dec 2023, 09:38 | 476 | 476 µS/cm |
| 20 Nov 2023, 10:12 | 527 | 527 µS/cm |
| 16 Oct 2023, 10:39 | 547 | 547 µS/cm |
Everything measured here
13 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 13 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 22 | Oct 2023 – May 2026 | 94.1% 7 May 2026 |
| Oxygen, Dissolved as O2 9924 | River water | 22 | Oct 2023 – May 2026 | 10.8 mg/l 7 May 2026 |
| Temperature of Water 0076 | River water | 22 | Oct 2023 – May 2026 | 9.2 °C 7 May 2026 |
| pH 0061 | River water | 22 | Oct 2023 – May 2026 | 8.1 7 May 2026 |
| Ammoniacal Nitrogen as N 0111 | River water | 22 | Oct 2023 – May 2026 | below 0.03 mg/l 7 May 2026 |
| Nitrate as N 0117 | River water | 22 | Oct 2023 – May 2026 | 0.303 mg/l 7 May 2026 |
| Orthophosphate, reactive as P 0180 | River water | 22 | Oct 2023 – May 2026 | 0.049 mg/l 7 May 2026 |
| Conductivity at 25 C 0077 | River water | 22 | Oct 2023 – May 2026 | 515 µS/cm 7 May 2026 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 22 | Oct 2023 – May 2026 | 200 mg/l 7 May 2026 |
| Ammonia un-ionised as N 0119 | River water | 22 | Oct 2023 – May 2026 | below 0.00052 mg/l 7 May 2026 |
| BOD : 5 Day ATU 0085 | River water | 18 | Feb 2024 – May 2026 | 1.9 mg/l 7 May 2026 |
| Nitrite as N 0118 | River water | 22 | Oct 2023 – May 2026 | 0.0067 mg/l 7 May 2026 |
| Nitrogen, Total Oxidised as N 0116 | River water | 22 | Oct 2023 – May 2026 | 0.31 mg/l 7 May 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.