Carnon at Twelveheads downstream of St Day Stream
EA name: CARNON AT TWELVEHEADS D/S ST DAY STREAM (also listed as “CARNON RIVER AT TWELVEHEADS, BELOW ST DAY STREAM”)
Environment Agency sampling point SW-81950622 · 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
- 24 Jul 2026, 12:022 months ago · time as the Environment Agency records it (UK clock time; the source gives no time zone)
- Samples banked
- 27 since 24 Apr 2024 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 176186, 41930As published, to the nearest 1 m. Open in a map
- River, by its own name
- Carnon
- River, by the map
- Carnon RiverPlaced on the river its name gives, 3 m from the line.
- Next gauge downstream
- Bissoe On the Carnon River · 1.6 km along the river
- Why it was sampled
- Monitoring (national agency policy) (27 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
99.9%
Sampled 24 Jul 2026, 2 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 24 Jul 2026, 12:02 | 99.9 | 99.9% |
| 5 May 2026, 10:58 | 96.5 | 96.5% |
| 17 Apr 2026, 12:43 | 100 | 100% |
| 9 Mar 2026, 13:46 | 97.8 | 97.8% |
| 17 Feb 2026, 13:51 | 97.9 | 97.9% |
| 30 Jan 2026, 14:06 | 95 | 95% |
| 30 Dec 2025, 13:19 | 98.3 | 98.3% |
| 28 Nov 2025, 13:05 | 97.8 | 97.8% |
| 24 Oct 2025, 12:49 | 96.8 | 96.8% |
| 15 Sep 2025, 13:47 | 101.6 | 101.6% |
| 29 Aug 2025, 12:59 | 97.8 | 97.8% |
| 28 Jul 2025, 12:16 | 98.8 | 98.8% |
| 16 Jun 2025, 13:16 | 101.2 | 101.2% |
| 29 May 2025, 13:01 | 102.8 | 102.8% |
| 24 Apr 2025, 11:03 | 100.9 | 100.9% |
| 18 Mar 2025, 10:14 | 100.3 | 100.3% |
| 18 Feb 2025, 10:32 | 96.9 | 96.9% |
| 29 Jan 2025, 12:37 | 96 | 96% |
| 11 Dec 2024, 11:50 | 96.2 | 96.2% |
| 20 Nov 2024, 12:00 | 97.7 | 97.7% |
| 15 Oct 2024, 11:32 | 99.3 | 99.3% |
| 27 Sep 2024, 10:47 | 104 | 104% |
| 14 Aug 2024, 12:56 | 100 | 100% |
| 22 Jul 2024, 12:02 | 100 | 100% |
| 13 Jun 2024, 11:37 | 98.1 | 98.1% |
| 9 May 2024, 11:02 | 100.9 | 100.9% |
| 24 Apr 2024, 11:44 | 100.2 | 100.2% |
Water temperature
code 0076 · °C
16.1 °C
Sampled 24 Jul 2026, 2 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 24 Jul 2026, 12:02 | 16.1 | 16.1 °C |
| 5 May 2026, 10:58 | 13 | 13 °C |
| 17 Apr 2026, 12:43 | 12.6 | 12.6 °C |
| 9 Mar 2026, 13:46 | 12.4 | 12.4 °C |
| 17 Feb 2026, 13:51 | 10.3 | 10.3 °C |
| 30 Jan 2026, 14:06 | 10.7 | 10.7 °C |
| 30 Dec 2025, 13:19 | 9.8 | 9.8 °C |
| 28 Nov 2025, 13:05 | 11.5 | 11.5 °C |
| 24 Oct 2025, 12:49 | 11.4 | 11.4 °C |
| 15 Sep 2025, 13:47 | 14.4 | 14.4 °C |
| 29 Aug 2025, 12:59 | 15.8 | 15.8 °C |
| 28 Jul 2025, 12:16 | 15.2 | 15.2 °C |
| 16 Jun 2025, 13:16 | 15.1 | 15.1 °C |
| 29 May 2025, 13:01 | 15 | 15 °C |
| 24 Apr 2025, 11:03 | 12.8 | 12.8 °C |
| 18 Mar 2025, 10:14 | 9.2 | 9.2 °C |
| 18 Feb 2025, 10:32 | 9.9 | 9.9 °C |
| 29 Jan 2025, 12:37 | 9.1 | 9.1 °C |
| 11 Dec 2024, 11:50 | 9.8 | 9.8 °C |
| 20 Nov 2024, 12:00 | 9 | 9 °C |
| 15 Oct 2024, 11:32 | 13.6 | 13.6 °C |
| 27 Sep 2024, 10:47 | 12.6 | 12.6 °C |
| 14 Aug 2024, 12:56 | 16.2 | 16.2 °C |
| 22 Jul 2024, 12:02 | 15.9 | 15.9 °C |
| 13 Jun 2024, 11:37 | 12.6 | 12.6 °C |
| 9 May 2024, 11:02 | 13.7 | 13.7 °C |
| 24 Apr 2024, 11:44 | 12 | 12 °C |
pH
code 0061
7.25
Sampled 24 Jul 2026, 2 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 24 Jul 2026, 12:02 | 7.25 | 7.25 |
| 5 May 2026, 10:58 | 7.11 | 7.11 |
| 17 Apr 2026, 12:43 | 6.8 | 6.8 |
| 9 Mar 2026, 13:46 | 6.86 | 6.86 |
| 17 Feb 2026, 13:51 | 6.79 | 6.79 |
| 30 Jan 2026, 14:06 | 6.67 | 6.67 |
| 30 Dec 2025, 13:19 | 6.9 | 6.9 |
| 28 Nov 2025, 13:05 | 6.9 | 6.9 |
| 24 Oct 2025, 12:49 | 7.05 | 7.05 |
| 15 Sep 2025, 13:47 | 7.41 | 7.41 |
| 29 Aug 2025, 12:59 | 7 | 7 |
| 28 Jul 2025, 12:16 | 7.2 | 7.2 |
| 16 Jun 2025, 13:16 | 7.12 | 7.12 |
| 29 May 2025, 13:01 | 7.1 | 7.1 |
| 24 Apr 2025, 11:03 | 7.05 | 7.05 |
| 18 Mar 2025, 10:14 | 7.03 | 7.03 |
| 18 Feb 2025, 10:32 | 7.04 | 7.04 |
| 29 Jan 2025, 12:37 | 6.95 | 6.95 |
| 11 Dec 2024, 11:50 | 7.01 | 7.01 |
| 20 Nov 2024, 12:00 | 7.22 | 7.22 |
| 15 Oct 2024, 11:32 | 6.98 | 6.98 |
| 27 Sep 2024, 10:47 | 7.26 | 7.26 |
| 14 Aug 2024, 12:56 | 7.37 | 7.37 |
| 22 Jul 2024, 12:02 | 7.24 | 7.24 |
| 13 Jun 2024, 11:37 | 6.77 | 6.77 |
| 9 May 2024, 11:02 | 7 | 7 |
| 24 Apr 2024, 11:44 | 6.97 | 6.97 |
Conductivity
at 25 °C · code 0077 · µS/cm
309 µS/cm
Sampled 24 Jul 2026, 2 months ago · 27 results banked
Every result (27)
| Sampled | Result as published | Reads as |
|---|---|---|
| 24 Jul 2026, 12:02 | 309 | 309 µS/cm |
| 5 May 2026, 10:58 | 265 | 265 µS/cm |
| 17 Apr 2026, 12:43 | 265 | 265 µS/cm |
| 9 Mar 2026, 13:46 | 252 | 252 µS/cm |
| 17 Feb 2026, 13:51 | 253 | 253 µS/cm |
| 30 Jan 2026, 14:06 | 233 | 233 µS/cm |
| 30 Dec 2025, 13:19 | 264 | 264 µS/cm |
| 28 Nov 2025, 13:05 | 258 | 258 µS/cm |
| 24 Oct 2025, 12:49 | 230 | 230 µS/cm |
| 15 Sep 2025, 13:47 | 273 | 273 µS/cm |
| 29 Aug 2025, 12:59 | 230 | 230 µS/cm |
| 28 Jul 2025, 12:16 | 289 | 289 µS/cm |
| 16 Jun 2025, 13:16 | 257 | 257 µS/cm |
| 29 May 2025, 13:01 | 269 | 269 µS/cm |
| 24 Apr 2025, 11:03 | 244 | 244 µS/cm |
| 18 Mar 2025, 10:14 | 259 | 259 µS/cm |
| 18 Feb 2025, 10:32 | 249 | 249 µS/cm |
| 29 Jan 2025, 12:37 | 241 | 241 µS/cm |
| 11 Dec 2024, 11:50 | 254 | 254 µS/cm |
| 20 Nov 2024, 12:00 | 274 | 274 µS/cm |
| 15 Oct 2024, 11:32 | 251 | 251 µS/cm |
| 27 Sep 2024, 10:47 | 242 | 242 µS/cm |
| 14 Aug 2024, 12:56 | 295 | 295 µS/cm |
| 22 Jul 2024, 12:02 | 269 | 269 µS/cm |
| 13 Jun 2024, 11:37 | 268 | 268 µS/cm |
| 9 May 2024, 11:02 | 253 | 253 µS/cm |
| 24 Apr 2024, 11:44 | 257 | 257 µS/cm |
Everything measured here
43 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 43 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 27 | Apr 2024 – Jul 2026 | 99.9% 24 Jul 2026 |
| Temperature of Water 0076 | River water | 27 | Apr 2024 – Jul 2026 | 16.1 °C 24 Jul 2026 |
| pH 0061 | River water | 27 | Apr 2024 – Jul 2026 | 7.25 24 Jul 2026 |
| Conductivity at 25 C 0077 | River water | 27 | Apr 2024 – Jul 2026 | 309 µS/cm 24 Jul 2026 |
| Aluminium 6057 | River water | 27 | Apr 2024 – Jul 2026 | 63 µg/l 24 Jul 2026 |
| Aluminium, Dissolved 6037 | River water | 27 | Apr 2024 – Jul 2026 | 50 µg/l 24 Jul 2026 |
| Arsenic 6046 | River water | 27 | Apr 2024 – Jul 2026 | 74 µg/l 24 Jul 2026 |
| Arsenic, Dissolved 6045 | River water | 27 | Apr 2024 – Jul 2026 | 72 µg/l 24 Jul 2026 |
| Barium 6062 | River water | 27 | Apr 2024 – Jul 2026 | below 10 µg/l 24 Jul 2026 |
| Barium, Dissolved 9446 | River water | 27 | Apr 2024 – Jul 2026 | below 10 µg/l 24 Jul 2026 |
| Boron 6059 | River water | 27 | Apr 2024 – Jul 2026 | below 100 µg/l 24 Jul 2026 |
| Boron, Dissolved 9447 | River water | 27 | Apr 2024 – Jul 2026 | below 100 µg/l 24 Jul 2026 |
| Cadmium 0108 | River water | 27 | Apr 2024 – Jul 2026 | 0.85 µg/l 24 Jul 2026 |
| Cadmium, Dissolved 0106 | River water | 27 | Apr 2024 – Jul 2026 | 0.88 µg/l 24 Jul 2026 |
| Calcium 0241 | River water | 27 | Apr 2024 – Jul 2026 | 16 mg/l 24 Jul 2026 |
| Calcium, Dissolved 0239 | River water | 27 | Apr 2024 – Jul 2026 | 16 mg/l 24 Jul 2026 |
| Carbon, Organic, Dissolved as C :- {DOC} 0301 | River water | 27 | Apr 2024 – Jul 2026 | 1.1 mg/l 24 Jul 2026 |
| Chromium 3164 | River water | 27 | Apr 2024 – Jul 2026 | below 0.5 µg/l 24 Jul 2026 |
| Chromium, Dissolved 3409 | River water | 27 | Apr 2024 – Jul 2026 | below 0.5 µg/l 24 Jul 2026 |
| Copper 6452 | River water | 27 | Apr 2024 – Jul 2026 | 65 µg/l 24 Jul 2026 |
| Copper, Dissolved 6450 | River water | 27 | Apr 2024 – Jul 2026 | 61 µg/l 24 Jul 2026 |
| Hardness, Total as CaCO3 0158 | River water | 27 | Apr 2024 – Jul 2026 | 68.4 mg/l 24 Jul 2026 |
| Iron 6051 | River water | 27 | Apr 2024 – Jul 2026 | 87 µg/l 24 Jul 2026 |
| Iron, Dissolved 6460 | River water | 27 | Apr 2024 – Jul 2026 | 50 µg/l 24 Jul 2026 |
| Lead, Dissolved 0052 | River water | 27 | Apr 2024 – Jul 2026 | below 2 µg/l 24 Jul 2026 |
| Lithium 6064 | River water | 27 | Apr 2024 – Jul 2026 | below 100 µg/l 24 Jul 2026 |
| Lithium, Dissolved 4201 | River water | 27 | Apr 2024 – Jul 2026 | below 100 µg/l 24 Jul 2026 |
| Magnesium 0237 | River water | 27 | Apr 2024 – Jul 2026 | 6.8 mg/l 24 Jul 2026 |
| Magnesium, Dissolved 0235 | River water | 27 | Apr 2024 – Jul 2026 | 6.9 mg/l 24 Jul 2026 |
| Manganese 6050 | River water | 27 | Apr 2024 – Jul 2026 | 38 µg/l 24 Jul 2026 |
| Manganese, Dissolved 6458 | River water | 27 | Apr 2024 – Jul 2026 | 38 µg/l 24 Jul 2026 |
| Nickel, Dissolved 3410 | River water | 27 | Apr 2024 – Jul 2026 | 19 µg/l 24 Jul 2026 |
| Potassium 0211 | River water | 27 | Apr 2024 – Jul 2026 | 3.5 mg/l 24 Jul 2026 |
| Potassium, Dissolved 0209 | River water | 27 | Apr 2024 – Jul 2026 | 3.6 mg/l 24 Jul 2026 |
| Sodium 0207 | River water | 27 | Apr 2024 – Jul 2026 | 29 mg/l 24 Jul 2026 |
| Sodium, Dissolved 0205 | River water | 27 | Apr 2024 – Jul 2026 | 30 mg/l 24 Jul 2026 |
| Solids, Suspended at 105 C 0135 | River water | 27 | Apr 2024 – Jul 2026 | below 3 mg/l 24 Jul 2026 |
| Strontium 6063 | River water | 27 | Apr 2024 – Jul 2026 | 68 µg/l 24 Jul 2026 |
| Strontium, Filtered 6693 | River water | 27 | Apr 2024 – Jul 2026 | 69 µg/l 24 Jul 2026 |
| Sulphate as SO4 0183 | River water | 27 | Apr 2024 – Jul 2026 | 35 mg/l 24 Jul 2026 |
| Sulphate, Dissolved as SO4 7859 | River water | 27 | Apr 2024 – Jul 2026 | 36 mg/l 24 Jul 2026 |
| Zinc 6455 | River water | 27 | Apr 2024 – Jul 2026 | 650 µg/l 24 Jul 2026 |
| Zinc, Dissolved 3408 | River water | 27 | Apr 2024 – Jul 2026 | 660 µg/l 24 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.