Thames at Old Windsor Lock
EA name: THAMES AT OLD WINDSOR LOCK
Environment Agency sampling point TH-RTN0038 · 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
- 22 Apr 2024, 09:282.5 years 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 25 Oct 2026 and had nothing newer.
- Samples banked
- 3 since 7 Nov 2023 Imported periods: 1 Oct 2023 – 25 Oct 2026. Samples outside them are not shown here.
- Latest sample
- River / running surface water Monitoring (national agency policy)
- Where
- National Grid 499456, 174702As published, to the nearest 1 m. Open in a map
- River, by its own name
- Thames
- River, by the map
- River ThamesPlaced on the river its name gives, 52 m from the line.
- Next gauge downstream
- Bell Weir On the River Thames · 4.6 km along the river
- Nearest gauge upstream
- Old Windsor Lock On the River Thames · 0.1 km along the river
- Why it was sampled
- Monitoring (national agency policy) (3 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
101.3%
Sampled 22 Apr 2024, 2.5 years ago · 3 results banked
Every result (3)
| Sampled | Result as published | Reads as |
|---|---|---|
| 22 Apr 2024, 09:28 | 101.3 | 101.3% |
| 25 Jan 2024, 11:45 | 100.7 | 100.7% |
| 7 Nov 2023, 13:22 | 95.4 | 95.4% |
Dissolved oxygen
as O2 · code 9924 · mg/l
11.2 mg/l
Sampled 22 Apr 2024, 2.5 years ago · 3 results banked
Every result (3)
| Sampled | Result as published | Reads as |
|---|---|---|
| 22 Apr 2024, 09:28 | 11.2 | 11.2 mg/l |
| 25 Jan 2024, 11:45 | 11.9 | 11.9 mg/l |
| 7 Nov 2023, 13:22 | 10.9 | 10.9 mg/l |
Water temperature
code 0076 · °C
10.9 °C
Sampled 22 Apr 2024, 2.5 years ago · 3 results banked
Every result (3)
| Sampled | Result as published | Reads as |
|---|---|---|
| 22 Apr 2024, 09:28 | 10.9 | 10.9 °C |
| 25 Jan 2024, 11:45 | 7.9 | 7.9 °C |
| 7 Nov 2023, 13:22 | 9.3 | 9.3 °C |
pH
code 0061
8.25
Sampled 22 Apr 2024, 2.5 years ago · 3 results banked
Every result (3)
| Sampled | Result as published | Reads as |
|---|---|---|
| 22 Apr 2024, 09:28 | 8.25 | 8.25 |
| 25 Jan 2024, 11:45 | 8.2 | 8.2 |
| 7 Nov 2023, 13:22 | 7.94 | 7.94 |
Conductivity
at 25 °C · code 0077 · µS/cm
634 µS/cm
Sampled 22 Apr 2024, 2.5 years ago · 3 results banked
Every result (3)
| Sampled | Result as published | Reads as |
|---|---|---|
| 22 Apr 2024, 09:28 | 634 | 634 µS/cm |
| 25 Jan 2024, 11:45 | 623 | 623 µS/cm |
| 7 Nov 2023, 13:22 | 535 | 535 µS/cm |
Everything measured here
5 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 5 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 3 | Nov 2023 – Apr 2024 | 101.3% 22 Apr 2024 |
| Oxygen, Dissolved as O2 9924 | River water | 3 | Nov 2023 – Apr 2024 | 11.2 mg/l 22 Apr 2024 |
| Temperature of Water 0076 | River water | 3 | Nov 2023 – Apr 2024 | 10.9 °C 22 Apr 2024 |
| pH 0061 | River water | 3 | Nov 2023 – Apr 2024 | 8.25 22 Apr 2024 |
| Conductivity at 25 C 0077 | River water | 3 | Nov 2023 – Apr 2024 | 634 µS/cm 22 Apr 2024 |
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.