Leigh-on-Mendip watercourse at Leigh-on-Mendip
EA name: LEIGH-ON-MENDIP W/C AT LEIGH-ON-MENDIP
Environment Agency sampling point SW-60120100 · 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
- 21 May 2026, 12:504 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
- 23 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 369414, 147146As published, to the nearest 1 m. Open in a map
- River, by its own name
- Leigh On Mendip West C
- River, by the map
- Not placedNo mapped watercourse within 500 m. The river map cannot say which watercourse this is.
- Next gauge downstream
- Not known
- Why it was sampled
- Monitoring (national agency policy) (23 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
99.9%
Sampled 21 May 2026, 4 months ago · 23 results banked
Every result (23)
| Sampled | Result as published | Reads as |
|---|---|---|
| 21 May 2026, 12:50 | 99.9 | 99.9% |
| 1 Apr 2026, 10:08 | 99.6 | 99.6% |
| 1 Apr 2026, 09:54 | 99.6 | 99.6% |
| 5 Feb 2026, 09:28 | 99.9 | 99.9% |
| 6 Jan 2026, 13:11 | 101.1 | 101.1% |
| 6 Mar 2025, 10:38 | 100.9 | 100.9% |
| 13 Feb 2025, 10:14 | 99.4 | 99.4% |
| 24 Jan 2025, 10:50 | 98.2 | 98.2% |
| 9 Dec 2024, 09:59 | 97.9 | 97.9% |
| 18 Nov 2024, 11:09 | 98.2 | 98.2% |
| 17 Oct 2024, 11:04 | 98.6 | 98.6% |
| 16 Sep 2024, 14:06 | 98.6 | 98.6% |
| 19 Aug 2024, 12:34 | 96.9 | 96.9% |
| 17 Jul 2024, 10:30 | 99.2 | 99.2% |
| 20 Jun 2024, 11:43 | 98.2 | 98.2% |
| 13 May 2024, 12:07 | 101.3 | 101.3% |
| 19 Apr 2024, 10:56 | 105.8 | 105.8% |
| 18 Mar 2024, 12:23 | 103.5 | 103.5% |
| 20 Feb 2024, 10:39 | 100.6 | 100.6% |
| 16 Jan 2024, 11:36 | 100.2 | 100.2% |
| 6 Dec 2023, 14:54 | 100.1 | 100.1% |
| 21 Nov 2023, 12:35 | 100.4 | 100.4% |
| 18 Oct 2023, 09:41 | 98.1 | 98.1% |
Dissolved oxygen
as O2 · code 9924 · mg/l
10 mg/l
Sampled 21 May 2026, 4 months ago · 23 results banked
Every result (23)
| Sampled | Result as published | Reads as |
|---|---|---|
| 21 May 2026, 12:50 | 10 | 10 mg/l |
| 1 Apr 2026, 10:08 | 11.2 | 11.2 mg/l |
| 1 Apr 2026, 09:54 | 11.2 | 11.2 mg/l |
| 5 Feb 2026, 09:28 | 12.1 | 12.1 mg/l |
| 6 Jan 2026, 13:11 | 13.5 | 13.5 mg/l |
| 6 Mar 2025, 10:38 | 12.1 | 12.1 mg/l |
| 13 Feb 2025, 10:14 | 12.5 | 12.5 mg/l |
| 24 Jan 2025, 10:50 | 11.9 | 11.9 mg/l |
| 9 Dec 2024, 09:59 | 11.7 | 11.7 mg/l |
| 18 Nov 2024, 11:09 | 11.2 | 11.2 mg/l |
| 17 Oct 2024, 11:04 | 10.4 | 10.4 mg/l |
| 16 Sep 2024, 14:06 | 9.85 | 9.85 mg/l |
| 19 Aug 2024, 12:34 | 9.58 | 9.58 mg/l |
| 17 Jul 2024, 10:30 | 9.77 | 9.77 mg/l |
| 20 Jun 2024, 11:43 | 9.77 | 9.77 mg/l |
| 13 May 2024, 12:07 | 10.4 | 10.4 mg/l |
| 19 Apr 2024, 10:56 | 11.7 | 11.7 mg/l |
| 18 Mar 2024, 12:23 | 11.5 | 11.5 mg/l |
| 20 Feb 2024, 10:39 | 11.6 | 11.6 mg/l |
| 16 Jan 2024, 11:36 | 13.2 | 13.2 mg/l |
| 6 Dec 2023, 14:54 | 12.1 | 12.1 mg/l |
| 21 Nov 2023, 12:35 | 11.3 | 11.3 mg/l |
| 18 Oct 2023, 09:41 | 10.9 | 10.9 mg/l |
Water temperature
code 0076 · °C
15.1 °C
Sampled 21 May 2026, 4 months ago · 23 results banked
Every result (23)
| Sampled | Result as published | Reads as |
|---|---|---|
| 21 May 2026, 12:50 | 15.1 | 15.1 °C |
| 1 Apr 2026, 10:08 | 10 | 10 °C |
| 1 Apr 2026, 09:54 | 10 | 10 °C |
| 5 Feb 2026, 09:28 | 7.1 | 7.1 °C |
| 6 Jan 2026, 13:11 | 3.2 | 3.2 °C |
| 6 Mar 2025, 10:38 | 7.3 | 7.3 °C |
| 13 Feb 2025, 10:14 | 5.5 | 5.5 °C |
| 24 Jan 2025, 10:50 | 7 | 7 °C |
| 9 Dec 2024, 09:59 | 7.4 | 7.4 °C |
| 18 Nov 2024, 11:09 | 9.4 | 9.4 °C |
| 17 Oct 2024, 11:04 | 12.8 | 12.8 °C |
| 16 Sep 2024, 14:06 | 15.3 | 15.3 °C |
| 19 Aug 2024, 12:34 | 15.8 | 15.8 °C |
| 17 Jul 2024, 10:30 | 16 | 16 °C |
| 20 Jun 2024, 11:43 | 15.5 | 15.5 °C |
| 13 May 2024, 12:07 | 14.2 | 14.2 °C |
| 19 Apr 2024, 10:56 | 10.7 | 10.7 °C |
| 18 Mar 2024, 12:23 | 10.5 | 10.5 °C |
| 20 Feb 2024, 10:39 | 9.2 | 9.2 °C |
| 16 Jan 2024, 11:36 | 3.9 | 3.9 °C |
| 6 Dec 2023, 14:54 | 7.2 | 7.2 °C |
| 21 Nov 2023, 12:35 | 10 | 10 °C |
| 18 Oct 2023, 09:41 | 10.6 | 10.6 °C |
pH
code 0061
8.13
Sampled 21 May 2026, 4 months ago · 23 results banked
Every result (23)
| Sampled | Result as published | Reads as |
|---|---|---|
| 21 May 2026, 12:50 | 8.13 | 8.13 |
| 1 Apr 2026, 10:08 | 8.27 | 8.27 |
| 1 Apr 2026, 09:54 | 8.27 | 8.27 |
| 5 Feb 2026, 09:28 | 8.15 | 8.15 |
| 6 Jan 2026, 13:11 | 8.27 | 8.27 |
| 6 Mar 2025, 10:38 | 8.38 | 8.38 |
| 13 Feb 2025, 10:14 | 8.29 | 8.29 |
| 24 Jan 2025, 10:50 | 8 | 8 |
| 9 Dec 2024, 09:59 | 8.09 | 8.09 |
| 18 Nov 2024, 11:09 | 7.99 | 7.99 |
| 17 Oct 2024, 11:04 | 7.97 | 7.97 |
| 16 Sep 2024, 14:06 | 8.35 | 8.35 |
| 19 Aug 2024, 12:34 | 8.33 | 8.33 |
| 17 Jul 2024, 10:30 | 8.42 | 8.42 |
| 20 Jun 2024, 11:43 | 8.31 | 8.31 |
| 13 May 2024, 12:07 | 8.59 | 8.59 |
| 19 Apr 2024, 10:56 | 8.46 | 8.46 |
| 18 Mar 2024, 12:23 | 8.18 | 8.18 |
| 20 Feb 2024, 10:39 | 8.06 | 8.06 |
| 16 Jan 2024, 11:36 | 8.37 | 8.37 |
| 6 Dec 2023, 14:54 | 8.08 | 8.08 |
| 21 Nov 2023, 12:35 | 8.16 | 8.16 |
| 18 Oct 2023, 09:41 | 8.27 | 8.27 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
0.042 mg/l
Sampled 21 May 2026, 4 months ago · 23 results banked
Every result (23)
| Sampled | Result as published | Reads as |
|---|---|---|
| 21 May 2026, 12:50 | 0.042 | 0.042 mg/l |
| 1 Apr 2026, 10:08 | <0.03 | below 0.03 mg/l (not detected above this) |
| 1 Apr 2026, 09:54 | <0.03 | below 0.03 mg/l (not detected above this) |
| 5 Feb 2026, 09:28 | <0.03 | below 0.03 mg/l (not detected above this) |
| 6 Jan 2026, 13:11 | <0.03 | below 0.03 mg/l (not detected above this) |
| 6 Mar 2025, 10:38 | <0.03 | below 0.03 mg/l (not detected above this) |
| 13 Feb 2025, 10:14 | <0.03 | below 0.03 mg/l (not detected above this) |
| 24 Jan 2025, 10:50 | 0.12 | 0.12 mg/l |
| 9 Dec 2024, 09:59 | <0.03 | below 0.03 mg/l (not detected above this) |
| 18 Nov 2024, 11:09 | 0.052 | 0.052 mg/l |
| 17 Oct 2024, 11:04 | <0.03 | below 0.03 mg/l (not detected above this) |
| 16 Sep 2024, 14:06 | <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) |
| 17 Jul 2024, 10:30 | <0.03 | below 0.03 mg/l (not detected above this) |
| 20 Jun 2024, 11:43 | 0.036 | 0.036 mg/l |
| 13 May 2024, 12:07 | <0.03 | below 0.03 mg/l (not detected above this) |
| 19 Apr 2024, 10:56 | <0.03 | below 0.03 mg/l (not detected above this) |
| 18 Mar 2024, 12:23 | <0.03 | below 0.03 mg/l (not detected above this) |
| 20 Feb 2024, 10:39 | <0.03 | below 0.03 mg/l (not detected above this) |
| 16 Jan 2024, 11:36 | <0.03 | below 0.03 mg/l (not detected above this) |
| 6 Dec 2023, 14:54 | <0.03 | below 0.03 mg/l (not detected above this) |
| 21 Nov 2023, 12:35 | <0.03 | below 0.03 mg/l (not detected above this) |
| 18 Oct 2023, 09:41 | <0.03 | below 0.03 mg/l (not detected above this) |
Nitrate
as nitrogen (N) · code 0117 · mg/l
2.09 mg/l
Sampled 21 May 2026, 4 months ago · 23 results banked
Every result (23)
| Sampled | Result as published | Reads as |
|---|---|---|
| 21 May 2026, 12:50 | 2.09 | 2.09 mg/l |
| 1 Apr 2026, 10:08 | 2.5 | 2.5 mg/l |
| 1 Apr 2026, 09:54 | 2.5 | 2.5 mg/l |
| 5 Feb 2026, 09:28 | 2.5 | 2.5 mg/l |
| 6 Jan 2026, 13:11 | 3.1 | 3.1 mg/l |
| 6 Mar 2025, 10:38 | 2.9 | 2.9 mg/l |
| 13 Feb 2025, 10:14 | 2.6 | 2.6 mg/l |
| 24 Jan 2025, 10:50 | 1.99 | 1.99 mg/l |
| 9 Dec 2024, 09:59 | 2.2 | 2.2 mg/l |
| 18 Nov 2024, 11:09 | 2.19 | 2.19 mg/l |
| 17 Oct 2024, 11:04 | 1.4 | 1.4 mg/l |
| 16 Sep 2024, 14:06 | 1.99 | 1.99 mg/l |
| 19 Aug 2024, 12:34 | 1.79 | 1.79 mg/l |
| 17 Jul 2024, 10:30 | 1.99 | 1.99 mg/l |
| 20 Jun 2024, 11:43 | 2.39 | 2.39 mg/l |
| 13 May 2024, 12:07 | 2.59 | 2.59 mg/l |
| 19 Apr 2024, 10:56 | 2.49 | 2.49 mg/l |
| 18 Mar 2024, 12:23 | 1.9 | 1.9 mg/l |
| 20 Feb 2024, 10:39 | 2.3 | 2.3 mg/l |
| 16 Jan 2024, 11:36 | 3.2 | 3.2 mg/l |
| 6 Dec 2023, 14:54 | 2.4 | 2.4 mg/l |
| 21 Nov 2023, 12:35 | 2.1 | 2.1 mg/l |
| 18 Oct 2023, 09:41 | 2.6 | 2.6 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.027 mg/l
Sampled 21 May 2026, 4 months ago · 23 results banked
Every result (23)
| Sampled | Result as published | Reads as |
|---|---|---|
| 21 May 2026, 12:50 | 0.027 | 0.027 mg/l |
| 1 Apr 2026, 10:08 | 0.021 | 0.021 mg/l |
| 1 Apr 2026, 09:54 | 0.019 | 0.019 mg/l |
| 5 Feb 2026, 09:28 | 0.02 | 0.02 mg/l |
| 6 Jan 2026, 13:11 | 0.023 | 0.023 mg/l |
| 6 Mar 2025, 10:38 | 0.015 | 0.015 mg/l |
| 13 Feb 2025, 10:14 | 0.023 | 0.023 mg/l |
| 24 Jan 2025, 10:50 | 0.085 | 0.085 mg/l |
| 9 Dec 2024, 09:59 | 0.024 | 0.024 mg/l |
| 18 Nov 2024, 11:09 | 0.062 | 0.062 mg/l |
| 17 Oct 2024, 11:04 | 0.044 | 0.044 mg/l |
| 16 Sep 2024, 14:06 | 0.031 | 0.031 mg/l |
| 19 Aug 2024, 12:34 | 0.039 | 0.039 mg/l |
| 17 Jul 2024, 10:30 | 0.031 | 0.031 mg/l |
| 20 Jun 2024, 11:43 | 0.018 | 0.018 mg/l |
| 13 May 2024, 12:07 | <0.01 | below 0.01 mg/l (not detected above this) |
| 19 Apr 2024, 10:56 | 0.014 | 0.014 mg/l |
| 18 Mar 2024, 12:23 | 0.021 | 0.021 mg/l |
| 20 Feb 2024, 10:39 | 0.021 | 0.021 mg/l |
| 16 Jan 2024, 11:36 | 0.02 | 0.02 mg/l |
| 6 Dec 2023, 14:54 | 0.024 | 0.024 mg/l |
| 21 Nov 2023, 12:35 | 0.02 | 0.02 mg/l |
| 18 Oct 2023, 09:41 | 0.029 | 0.029 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
423 µS/cm
Sampled 21 May 2026, 4 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 21 May 2026, 12:50 | 423 | 423 µS/cm |
| 1 Apr 2026, 10:08 | 378 | 378 µS/cm |
| 1 Apr 2026, 09:54 | 378 | 378 µS/cm |
| 5 Feb 2026, 09:28 | 281 | 281 µS/cm |
| 6 Jan 2026, 13:11 | 381 | 381 µS/cm |
| 6 Mar 2025, 10:38 | 356 | 356 µS/cm |
| 13 Feb 2025, 10:14 | 347 | 347 µS/cm |
| 24 Jan 2025, 10:50 | 328 | 328 µS/cm |
| 9 Dec 2024, 09:59 | 319 | 319 µS/cm |
| 18 Nov 2024, 11:09 | 332 | 332 µS/cm |
| 17 Oct 2024, 11:04 | 270 | 270 µS/cm |
| 16 Sep 2024, 14:06 | 387 | 387 µS/cm |
| 19 Aug 2024, 12:34 | 422 | 422 µS/cm |
| 17 Jul 2024, 10:30 | 405 | 405 µS/cm |
| 13 May 2024, 12:07 | 384 | 384 µS/cm |
| 19 Apr 2024, 10:56 | 355 | 355 µS/cm |
| 18 Mar 2024, 12:23 | 295 | 295 µS/cm |
| 20 Feb 2024, 10:39 | 289 | 289 µS/cm |
| 16 Jan 2024, 11:36 | 367 | 367 µS/cm |
| 6 Dec 2023, 14:54 | 293 | 293 µS/cm |
| 21 Nov 2023, 12:35 | 313 | 313 µS/cm |
| 18 Oct 2023, 09:41 | 356 | 356 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 | 23 | Oct 2023 – May 2026 | 99.9% 21 May 2026 |
| Oxygen, Dissolved as O2 9924 | River water | 23 | Oct 2023 – May 2026 | 10 mg/l 21 May 2026 |
| Temperature of Water 0076 | River water | 23 | Oct 2023 – May 2026 | 15.1 °C 21 May 2026 |
| pH 0061 | River water | 23 | Oct 2023 – May 2026 | 8.13 21 May 2026 |
| Ammoniacal Nitrogen as N 0111 | River water | 23 | Oct 2023 – May 2026 | 0.042 mg/l 21 May 2026 |
| Nitrate as N 0117 | River water | 23 | Oct 2023 – May 2026 | 2.09 mg/l 21 May 2026 |
| Orthophosphate, reactive as P 0180 | River water | 23 | Oct 2023 – May 2026 | 0.027 mg/l 21 May 2026 |
| Conductivity at 25 C 0077 | River water | 22 | Oct 2023 – May 2026 | 423 µS/cm 21 May 2026 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 23 | Oct 2023 – May 2026 | 190 mg/l 21 May 2026 |
| Ammonia un-ionised as N 0119 | River water | 23 | Oct 2023 – May 2026 | 0.00111 mg/l 21 May 2026 |
| BOD : 5 Day ATU 0085 | River water | 19 | Feb 2024 – May 2026 | 1.4 mg/l 21 May 2026 |
| Nitrite as N 0118 | River water | 23 | Oct 2023 – May 2026 | 0.015 mg/l 21 May 2026 |
| Nitrogen, Total Oxidised as N 0116 | River water | 23 | Oct 2023 – May 2026 | 2.1 mg/l 21 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.