Vyrnwy at Hendre
EA name: RSN1419 VYRNWY AT HENDRE
Environment Agency sampling point MD-RSN1419 · 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
- 10 Oct 2025, 11:5812 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 8 Oct 2026 and had nothing newer.
- Samples banked
- 9 since 20 Feb 2025 Imported periods: 1 Oct 2023 – 8 Oct 2026. Samples outside them are not shown here.
- Latest sample
- River / running surface water Monitoring (national agency policy)
- Where
- National Grid 331805, 317404As published, to the nearest 1 m. Open in a map
- River, by its own name
- Vyrnwy
- River, by the map
- Afon EfyrnwyPlaced on the river its name gives, 9 m from the line.
- Next gauge downstream
- Crew Green On the River Severn · 3.3 km along the river
- Nearest gauge upstream
- Llanymynech River Station On the Vyrnwy · 15 km along the river
- Why it was sampled
- Monitoring (national agency policy) (9 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
95.4%
Sampled 10 Oct 2025, 12 months ago · 9 results banked
Every result (9)
| Sampled | Result as published | Reads as |
|---|---|---|
| 10 Oct 2025, 11:58 | 95.4 | 95.4% |
| 1 Sep 2025, 10:51 | 94.7 | 94.7% |
| 8 Aug 2025, 12:25 | 104.6 | 104.6% |
| 9 Jul 2025, 13:01 | 96 | 96% |
| 12 Jun 2025, 14:12 | 95.8 | 95.8% |
| 21 May 2025, 12:39 | 92.7 | 92.7% |
| 4 Apr 2025, 13:20 | 108.2 | 108.2% |
| 13 Mar 2025, 13:02 | 97.9 | 97.9% |
| 20 Feb 2025, 11:20 | 101.1 | 101.1% |
Dissolved oxygen
as O2 · code 9924 · mg/l
10.1 mg/l
Sampled 10 Oct 2025, 12 months ago · 9 results banked
Every result (9)
| Sampled | Result as published | Reads as |
|---|---|---|
| 10 Oct 2025, 11:58 | 10.1 | 10.1 mg/l |
| 1 Sep 2025, 10:51 | 9.3 | 9.3 mg/l |
| 8 Aug 2025, 12:25 | 9.96 | 9.96 mg/l |
| 9 Jul 2025, 13:01 | 8.85 | 8.85 mg/l |
| 12 Jun 2025, 14:12 | 9.29 | 9.29 mg/l |
| 21 May 2025, 12:39 | 8.95 | 8.95 mg/l |
| 4 Apr 2025, 13:20 | 11.3 | 11.3 mg/l |
| 13 Mar 2025, 13:02 | 11.8 | 11.8 mg/l |
| 20 Feb 2025, 11:20 | 12.3 | 12.3 mg/l |
Water temperature
code 0076 · °C
12.5 °C
Sampled 10 Oct 2025, 12 months ago · 9 results banked
Every result (9)
| Sampled | Result as published | Reads as |
|---|---|---|
| 10 Oct 2025, 11:58 | 12.5 | 12.5 °C |
| 1 Sep 2025, 10:51 | 16.1 | 16.1 °C |
| 8 Aug 2025, 12:25 | 17.6 | 17.6 °C |
| 9 Jul 2025, 13:01 | 19.2 | 19.2 °C |
| 12 Jun 2025, 14:12 | 16.7 | 16.7 °C |
| 21 May 2025, 12:39 | 16.9 | 16.9 °C |
| 4 Apr 2025, 13:20 | 13.2 | 13.2 °C |
| 13 Mar 2025, 13:02 | 7.2 | 7.2 °C |
| 20 Feb 2025, 11:20 | 6.9 | 6.9 °C |
pH
code 0061
7.93
Sampled 10 Oct 2025, 12 months ago · 9 results banked
Every result (9)
| Sampled | Result as published | Reads as |
|---|---|---|
| 10 Oct 2025, 11:58 | 7.93 | 7.93 |
| 1 Sep 2025, 10:51 | 7.9 | 7.9 |
| 8 Aug 2025, 12:25 | 8.31 | 8.31 |
| 9 Jul 2025, 13:01 | 8.42 | 8.42 |
| 12 Jun 2025, 14:12 | 7.6 | 7.6 |
| 21 May 2025, 12:39 | 7.67 | 7.67 |
| 4 Apr 2025, 13:20 | 7.97 | 7.97 |
| 13 Mar 2025, 13:02 | 7.95 | 7.95 |
| 20 Feb 2025, 11:20 | 8.02 | 8.02 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
below 0.03 mg/l (not detected above this)
Sampled 10 Oct 2025, 12 months ago · 9 results banked
Every result (9)
| Sampled | Result as published | Reads as |
|---|---|---|
| 10 Oct 2025, 11:58 | <0.03 | below 0.03 mg/l (not detected above this) |
| 1 Sep 2025, 10:51 | <0.03 | below 0.03 mg/l (not detected above this) |
| 8 Aug 2025, 12:25 | <0.03 | below 0.03 mg/l (not detected above this) |
| 9 Jul 2025, 13:01 | <0.03 | below 0.03 mg/l (not detected above this) |
| 12 Jun 2025, 14:12 | <0.03 | below 0.03 mg/l (not detected above this) |
| 21 May 2025, 12:39 | 0.046 | 0.046 mg/l |
| 4 Apr 2025, 13:20 | <0.03 | below 0.03 mg/l (not detected above this) |
| 13 Mar 2025, 13:02 | <0.03 | below 0.03 mg/l (not detected above this) |
| 20 Feb 2025, 11:20 | 0.092 | 0.092 mg/l |
Nitrate
as nitrogen (N) · code 0117 · mg/l
0.996 mg/l
Sampled 10 Oct 2025, 12 months ago · 9 results banked
Every result (9)
| Sampled | Result as published | Reads as |
|---|---|---|
| 10 Oct 2025, 11:58 | 0.996 | 0.996 mg/l |
| 1 Sep 2025, 10:51 | 0.996 | 0.996 mg/l |
| 8 Aug 2025, 12:25 | 0.786 | 0.786 mg/l |
| 9 Jul 2025, 13:01 | 0.836 | 0.836 mg/l |
| 12 Jun 2025, 14:12 | 0.946 | 0.946 mg/l |
| 21 May 2025, 12:39 | 1.49 | 1.49 mg/l |
| 4 Apr 2025, 13:20 | 1.79 | 1.79 mg/l |
| 13 Mar 2025, 13:02 | 2.09 | 2.09 mg/l |
| 20 Feb 2025, 11:20 | 2.29 | 2.29 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.023 mg/l
Sampled 10 Oct 2025, 12 months ago · 9 results banked
Every result (9)
| Sampled | Result as published | Reads as |
|---|---|---|
| 10 Oct 2025, 11:58 | 0.023 | 0.023 mg/l |
| 1 Sep 2025, 10:51 | 0.022 | 0.022 mg/l |
| 8 Aug 2025, 12:25 | 0.028 | 0.028 mg/l |
| 9 Jul 2025, 13:01 | 0.053 | 0.053 mg/l |
| 12 Jun 2025, 14:12 | 0.027 | 0.027 mg/l |
| 21 May 2025, 12:39 | 0.03 | 0.03 mg/l |
| 4 Apr 2025, 13:20 | <0.01 | below 0.01 mg/l (not detected above this) |
| 13 Mar 2025, 13:02 | 0.032 | 0.032 mg/l |
| 20 Feb 2025, 11:20 | 0.052 | 0.052 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
158 µS/cm
Sampled 10 Oct 2025, 12 months ago · 9 results banked
Every result (9)
| Sampled | Result as published | Reads as |
|---|---|---|
| 10 Oct 2025, 11:58 | 158 | 158 µS/cm |
| 1 Sep 2025, 10:51 | 229 | 229 µS/cm |
| 8 Aug 2025, 12:25 | 179 | 179 µS/cm |
| 9 Jul 2025, 13:01 | 119 | 119 µS/cm |
| 12 Jun 2025, 14:12 | 140 | 140 µS/cm |
| 21 May 2025, 12:39 | 209 | 209 µS/cm |
| 4 Apr 2025, 13:20 | 230 | 230 µS/cm |
| 13 Mar 2025, 13:02 | 214 | 214 µS/cm |
| 20 Feb 2025, 11:20 | 225 | 225 µS/cm |
Everything measured here
18 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 18 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 9 | Feb 2025 – Oct 2025 | 95.4% 10 Oct 2025 |
| Oxygen, Dissolved as O2 9924 | River water | 9 | Feb 2025 – Oct 2025 | 10.1 mg/l 10 Oct 2025 |
| Temperature of Water 0076 | River water | 9 | Feb 2025 – Oct 2025 | 12.5 °C 10 Oct 2025 |
| pH 0061 | River water | 9 | Feb 2025 – Oct 2025 | 7.93 10 Oct 2025 |
| Ammoniacal Nitrogen as N 0111 | River water | 9 | Feb 2025 – Oct 2025 | below 0.03 mg/l 10 Oct 2025 |
| Nitrate as N 0117 | River water | 9 | Feb 2025 – Oct 2025 | 0.996 mg/l 10 Oct 2025 |
| Orthophosphate, reactive as P 0180 | River water | 9 | Feb 2025 – Oct 2025 | 0.023 mg/l 10 Oct 2025 |
| Conductivity at 25 C 0077 | River water | 9 | Feb 2025 – Oct 2025 | 158 µS/cm 10 Oct 2025 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 9 | Feb 2025 – Oct 2025 | 27 mg/l 10 Oct 2025 |
| Ammonia un-ionised as N 0119 | River water | 9 | Feb 2025 – Oct 2025 | below 0.00056 mg/l 10 Oct 2025 |
| Carbon, Organic, Dissolved as C :- {DOC} 0301 | River water | 8 | Feb 2025 – Sep 2025 | 2.7 mg/l 1 Sep 2025 |
| Chloride 0172 | River water | 9 | Feb 2025 – Oct 2025 | 11 mg/l 10 Oct 2025 |
| Flow Type 2896 | River water | 9 | Feb 2025 – Oct 2025 | High Flow 10 Oct 2025 |
| Nitrite as N 0118 | River water | 9 | Feb 2025 – Oct 2025 | below 0.004 mg/l 10 Oct 2025 |
| Nitrogen, Total as N 9686 | River water | 9 | Feb 2025 – Oct 2025 | 1.3 mg/l 10 Oct 2025 |
| Nitrogen, Total Oxidised as N 0116 | River water | 9 | Feb 2025 – Oct 2025 | 1 mg/l 10 Oct 2025 |
| Phosphorus, Total as P 0348 | River water | 9 | Feb 2025 – Oct 2025 | 0.031 mg/l 10 Oct 2025 |
| Silica, reactive as SiO2 0182 | River water | 9 | Feb 2025 – Oct 2025 | 4.7 mg/l 10 Oct 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.