River Clyst at Clyst Hydon (Twynhayes Farm)
EA name: R. CLYST AT CLYST HYDON (TWYNHAYES FM.) (also listed as “RSN0499 CLYST HYDON - R. CLYST AT TWYNHAYES FARM (CLYST)”)
Environment Agency sampling point SW-RSN0499 · 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 Sep 2026, 10:4117 days ago · time as the Environment Agency records it (UK clock time; the source gives no time zone)
- Samples banked
- 21 since 13 Jan 2025 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 304358, 101943As published, to the nearest 1 m. Open in a map
- River, by its own name
- Clyst
- 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) (21 samples)
4 visits found no water to sample (recorded as “No flow”).
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
75.4%
Sampled 9 Jun 2026, 4 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 9 Jun 2026, 13:07 | 75.4 | 75.4% |
| 11 May 2026, 15:41 | 90 | 90% |
| 24 Apr 2026, 14:22 | 95.8 | 95.8% |
| 2 Mar 2026, 14:56 | 86.4 | 86.4% |
| 5 Feb 2026, 11:32 | 87.2 | 87.2% |
| 22 Jan 2026, 10:26 | 86.5 | 86.5% |
| 4 Dec 2025, 11:04 | 91.4 | 91.4% |
| 20 Nov 2025, 09:56 | 90.2 | 90.2% |
| 24 Oct 2025, 13:42 | 80.6 | 80.6% |
| 10 Sep 2025, 15:11 | 68.5 | 68.5% |
| 23 Jul 2025, 11:05 | 70.6 | 70.6% |
| 27 Jun 2025, 10:55 | 82.6 | 82.6% |
| 16 May 2025, 10:38 | 91 | 91% |
| 11 Apr 2025, 12:14 | 91.7 | 91.7% |
| 12 Mar 2025, 14:00 | 96.9 | 96.9% |
| 3 Feb 2025, 09:15 | 92.5 | 92.5% |
| 13 Jan 2025, 11:37 | 93.8 | 93.8% |
Dissolved oxygen
as O2 · code 9924 · mg/l
7.87 mg/l
Sampled 9 Jun 2026, 4 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 9 Jun 2026, 13:07 | 7.87 | 7.87 mg/l |
| 11 May 2026, 15:41 | 9.85 | 9.85 mg/l |
| 24 Apr 2026, 14:22 | 10.4 | 10.4 mg/l |
| 2 Mar 2026, 14:56 | 9.51 | 9.51 mg/l |
| 5 Feb 2026, 11:32 | 10.2 | 10.2 mg/l |
| 22 Jan 2026, 10:26 | 10.3 | 10.3 mg/l |
| 4 Dec 2025, 11:04 | 10.7 | 10.7 mg/l |
| 20 Nov 2025, 09:56 | 11.3 | 11.3 mg/l |
| 24 Oct 2025, 13:42 | 9.23 | 9.23 mg/l |
| 10 Sep 2025, 15:11 | 6.86 | 6.86 mg/l |
| 23 Jul 2025, 11:05 | 6.86 | 6.86 mg/l |
| 27 Jun 2025, 10:55 | 8.04 | 8.04 mg/l |
| 16 May 2025, 10:38 | 9.76 | 9.76 mg/l |
| 11 Apr 2025, 12:14 | 10.8 | 10.8 mg/l |
| 12 Mar 2025, 14:00 | 11.8 | 11.8 mg/l |
| 3 Feb 2025, 09:15 | 11.2 | 11.2 mg/l |
| 13 Jan 2025, 11:37 | 11.7 | 11.7 mg/l |
Water temperature
code 0076 · °C
13.3 °C
Sampled 9 Jun 2026, 4 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 9 Jun 2026, 13:07 | 13.3 | 13.3 °C |
| 11 May 2026, 15:41 | 11.2 | 11.2 °C |
| 24 Apr 2026, 14:22 | 11.7 | 11.7 °C |
| 2 Mar 2026, 14:56 | 11 | 11 °C |
| 5 Feb 2026, 11:32 | 8.5 | 8.5 °C |
| 22 Jan 2026, 10:26 | 7.7 | 7.7 °C |
| 4 Dec 2025, 11:04 | 8.4 | 8.4 °C |
| 20 Nov 2025, 09:56 | 5.6 | 5.6 °C |
| 24 Oct 2025, 13:42 | 9.3 | 9.3 °C |
| 10 Sep 2025, 15:11 | 15.2 | 15.2 °C |
| 23 Jul 2025, 11:05 | 16.6 | 16.6 °C |
| 27 Jun 2025, 10:55 | 16.5 | 16.5 °C |
| 16 May 2025, 10:38 | 12.1 | 12.1 °C |
| 11 Apr 2025, 12:14 | 8.1 | 8.1 °C |
| 12 Mar 2025, 14:00 | 6.9 | 6.9 °C |
| 3 Feb 2025, 09:15 | 7.2 | 7.2 °C |
| 13 Jan 2025, 11:37 | 5.7 | 5.7 °C |
pH
code 0061
7.51
Sampled 9 Jun 2026, 4 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 9 Jun 2026, 13:07 | 7.51 | 7.51 |
| 11 May 2026, 15:41 | 7.78 | 7.78 |
| 24 Apr 2026, 14:22 | 8.03 | 8.03 |
| 2 Mar 2026, 14:56 | 7.56 | 7.56 |
| 5 Feb 2026, 11:32 | 7.26 | 7.26 |
| 22 Jan 2026, 10:26 | 6.56 | 6.56 |
| 4 Dec 2025, 11:04 | 7.36 | 7.36 |
| 20 Nov 2025, 09:56 | 7.64 | 7.64 |
| 24 Oct 2025, 13:42 | 7.8 | 7.8 |
| 10 Sep 2025, 15:11 | 7.46 | 7.46 |
| 23 Jul 2025, 11:05 | 7.83 | 7.83 |
| 27 Jun 2025, 10:55 | 8.01 | 8.01 |
| 16 May 2025, 10:38 | 8.04 | 8.04 |
| 11 Apr 2025, 12:14 | 8 | 8 |
| 12 Mar 2025, 14:00 | 7.89 | 7.89 |
| 3 Feb 2025, 09:15 | 7.61 | 7.61 |
| 13 Jan 2025, 11:37 | 7.75 | 7.75 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
0.099 mg/l
Sampled 9 Jun 2026, 4 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 9 Jun 2026, 13:07 | 0.099 | 0.099 mg/l |
| 11 May 2026, 15:41 | 0.034 | 0.034 mg/l |
| 24 Apr 2026, 14:22 | 0.036 | 0.036 mg/l |
| 2 Mar 2026, 14:56 | 0.4 | 0.4 mg/l |
| 5 Feb 2026, 11:32 | 0.31 | 0.31 mg/l |
| 22 Jan 2026, 10:26 | 0.056 | 0.056 mg/l |
| 4 Dec 2025, 11:04 | 0.093 | 0.093 mg/l |
| 20 Nov 2025, 09:56 | <0.03 | below 0.03 mg/l (not detected above this) |
| 24 Oct 2025, 13:42 | <0.03 | below 0.03 mg/l (not detected above this) |
| 10 Sep 2025, 15:11 | 0.055 | 0.055 mg/l |
| 23 Jul 2025, 11:05 | 0.03 | 0.03 mg/l |
| 27 Jun 2025, 10:55 | 0.051 | 0.051 mg/l |
| 16 May 2025, 10:38 | 0.047 | 0.047 mg/l |
| 11 Apr 2025, 12:14 | <0.03 | below 0.03 mg/l (not detected above this) |
| 12 Mar 2025, 14:00 | 0.077 | 0.077 mg/l |
| 3 Feb 2025, 09:15 | 0.12 | 0.12 mg/l |
| 13 Jan 2025, 11:37 | 0.077 | 0.077 mg/l |
Nitrate
as nitrogen (N) · code 0117 · mg/l
5.54 mg/l
Sampled 9 Jun 2026, 4 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 9 Jun 2026, 13:07 | 5.54 | 5.54 mg/l |
| 11 May 2026, 15:41 | 7.07 | 7.07 mg/l |
| 24 Apr 2026, 14:22 | 7.27 | 7.27 mg/l |
| 2 Mar 2026, 14:56 | 2.02 | 2.02 mg/l |
| 5 Feb 2026, 11:32 | 1.69 | 1.69 mg/l |
| 22 Jan 2026, 10:26 | 1.99 | 1.99 mg/l |
| 4 Dec 2025, 11:04 | 7.19 | 7.19 mg/l |
| 20 Nov 2025, 09:56 | 9.78 | 9.78 mg/l |
| 24 Oct 2025, 13:42 | 2.78 | 2.78 mg/l |
| 10 Sep 2025, 15:11 | 2.63 | 2.63 mg/l |
| 23 Jul 2025, 11:05 | 3.28 | 3.28 mg/l |
| 27 Jun 2025, 10:55 | 5.47 | 5.47 mg/l |
| 16 May 2025, 10:38 | 6.95 | 6.95 mg/l |
| 11 Apr 2025, 12:14 | 7.08 | 7.08 mg/l |
| 12 Mar 2025, 14:00 | 4.97 | 4.97 mg/l |
| 3 Feb 2025, 09:15 | 3.88 | 3.88 mg/l |
| 13 Jan 2025, 11:37 | 4.28 | 4.28 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.3 mg/l
Sampled 9 Jun 2026, 4 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 9 Jun 2026, 13:07 | 0.3 | 0.3 mg/l |
| 11 May 2026, 15:41 | 0.22 | 0.22 mg/l |
| 24 Apr 2026, 14:22 | 0.17 | 0.17 mg/l |
| 2 Mar 2026, 14:56 | 0.23 | 0.23 mg/l |
| 5 Feb 2026, 11:32 | 0.29 | 0.29 mg/l |
| 22 Jan 2026, 10:26 | 0.31 | 0.31 mg/l |
| 4 Dec 2025, 11:04 | 0.16 | 0.16 mg/l |
| 20 Nov 2025, 09:56 | 0.12 | 0.12 mg/l |
| 24 Oct 2025, 13:42 | 0.4 | 0.4 mg/l |
| 10 Sep 2025, 15:11 | 0.5 | 0.5 mg/l |
| 23 Jul 2025, 11:05 | 0.4 | 0.4 mg/l |
| 27 Jun 2025, 10:55 | 0.34 | 0.34 mg/l |
| 16 May 2025, 10:38 | 0.23 | 0.23 mg/l |
| 11 Apr 2025, 12:14 | 0.11 | 0.11 mg/l |
| 12 Mar 2025, 14:00 | 0.13 | 0.13 mg/l |
| 3 Feb 2025, 09:15 | 0.12 | 0.12 mg/l |
| 13 Jan 2025, 11:37 | 0.12 | 0.12 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
502 µS/cm
Sampled 9 Jun 2026, 4 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 9 Jun 2026, 13:07 | 502 | 502 µS/cm |
| 11 May 2026, 15:41 | 541 | 541 µS/cm |
| 24 Apr 2026, 14:22 | 580 | 580 µS/cm |
| 2 Mar 2026, 14:56 | 441 | 441 µS/cm |
| 5 Feb 2026, 11:32 | 304 | 304 µS/cm |
| 22 Jan 2026, 10:26 | 250 | 250 µS/cm |
| 4 Dec 2025, 11:04 | 449 | 449 µS/cm |
| 20 Nov 2025, 09:56 | 624 | 624 µS/cm |
| 24 Oct 2025, 13:42 | 507 | 507 µS/cm |
| 10 Sep 2025, 15:11 | 430 | 430 µS/cm |
| 23 Jul 2025, 11:05 | 547 | 547 µS/cm |
| 27 Jun 2025, 10:55 | 549 | 549 µS/cm |
| 16 May 2025, 10:38 | 618 | 618 µS/cm |
| 11 Apr 2025, 12:14 | 647 | 647 µS/cm |
| 12 Mar 2025, 14:00 | 619 | 619 µS/cm |
| 3 Feb 2025, 09:15 | 495 | 495 µS/cm |
| 13 Jan 2025, 11:37 | 558 | 558 µS/cm |
Everything measured here
21 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 21 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 17 | Jan 2025 – Jun 2026 | 75.4% 9 Jun 2026 |
| Oxygen, Dissolved as O2 9924 | River water | 17 | Jan 2025 – Jun 2026 | 7.87 mg/l 9 Jun 2026 |
| Temperature of Water 0076 | River water | 17 | Jan 2025 – Jun 2026 | 13.3 °C 9 Jun 2026 |
| pH 0061 | River water | 17 | Jan 2025 – Jun 2026 | 7.51 9 Jun 2026 |
| Ammoniacal Nitrogen as N 0111 | River water | 17 | Jan 2025 – Jun 2026 | 0.099 mg/l 9 Jun 2026 |
| Nitrate as N 0117 | River water | 17 | Jan 2025 – Jun 2026 | 5.54 mg/l 9 Jun 2026 |
| Orthophosphate, reactive as P 0180 | River water | 17 | Jan 2025 – Jun 2026 | 0.3 mg/l 9 Jun 2026 |
| Conductivity at 25 C 0077 | River water | 17 | Jan 2025 – Jun 2026 | 502 µS/cm 9 Jun 2026 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 17 | Jan 2025 – Jun 2026 | 140 mg/l 9 Jun 2026 |
| Ammonia un-ionised as N 0119 | River water | 17 | Jan 2025 – Jun 2026 | 0.00076 mg/l 9 Jun 2026 |
| Carbon, Organic, Dissolved as C :- {DOC} 0301 | River water | 17 | Jan 2025 – Jun 2026 | 5.4 mg/l 9 Jun 2026 |
| Chloride 0172 | River water | 17 | Jan 2025 – Jun 2026 | 32 mg/l 9 Jun 2026 |
| Flow Type 2896 | River water | 19 | Jan 2025 – Sep 2026 | Dry 14 Sep 2026 |
| LCMS Screen : Semi Quantitative 7299 | River water | 2 | Feb 2026 – May 2026 | 1 text result 11 May 2026 |
| Nitrite as N 0118 | River water | 17 | Jan 2025 – Jun 2026 | 0.061 mg/l 9 Jun 2026 |
| Nitrogen, Total as N 9686 | River water | 17 | Jan 2025 – Jun 2026 | 6.9 mg/l 9 Jun 2026 |
| Nitrogen, Total Oxidised as N 0116 | River water | 17 | Jan 2025 – Jun 2026 | 5.6 mg/l 9 Jun 2026 |
| No flow /No sample 7668 | River water | 4 | Aug 2025 – Sep 2026 | No flow/discharge at sampling point 14 Sep 2026 |
| Phosphorus, Total as P 0348 | River water | 17 | Jan 2025 – Jun 2026 | 0.45 mg/l 9 Jun 2026 |
| Silica, reactive as SiO2 0182 | River water | 17 | Jan 2025 – Jun 2026 | 9.3 mg/l 9 Jun 2026 |
| Solids, Suspended at 105 C 0135 | River water | 7 | Dec 2025 – Jun 2026 | 88 mg/l 9 Jun 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.