Lee Navigation at Saracens Head gauging station
EA name: LEE NAVIGATION AT SARACENS HEAD GS
Environment Agency sampling point TH-RTN0004 · 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 Jan 2026, 14:099 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
- 10 since 23 Oct 2023 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 535905, 214167As published, to the nearest 1 m. Open in a map
- River, by its own name
- Lee Navigation
- River, by the map
- River LeaPlaced on a river whose name partly matches its own, 14 m from the line.
- Next gauge downstream
- Tumbling Bay Weir On the Amwell Loop · 0.5 km along the river
- Nearest gauge upstream
- Hertford, Hartham Park On the River Beane · 4.1 km along the riverWaterhall On the River Lee · 9.3 km along the riverWadesmill On the River Rib · 9.7 km along the river
- Why it was sampled
- Monitoring (national agency policy) (10 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
94.4%
Sampled 14 Jan 2026, 9 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Jan 2026, 14:09 | 94.4 | 94.4% |
| 7 Oct 2025, 12:02 | 96.6 | 96.6% |
| 21 Jul 2025, 09:03 | 89.1 | 89.1% |
| 3 Apr 2025, 13:31 | 102.6 | 102.6% |
| 21 Jan 2025, 12:39 | 95.8 | 95.8% |
| 4 Oct 2024, 13:50 | 97.6 | 97.6% |
| 3 Jul 2024, 09:15 | 96.7 | 96.7% |
| 2 Apr 2024, 13:52 | 102.8 | 102.8% |
| 3 Jan 2024, 12:10 | 98.3 | 98.3% |
| 23 Oct 2023, 12:54 | 95.1 | 95.1% |
Dissolved oxygen
as O2 · code 9924 · mg/l
11.6 mg/l
Sampled 14 Jan 2026, 9 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Jan 2026, 14:09 | 11.6 | 11.6 mg/l |
| 7 Oct 2025, 12:02 | 10 | 10 mg/l |
| 21 Jul 2025, 09:03 | 8.57 | 8.57 mg/l |
| 3 Apr 2025, 13:31 | 11.3 | 11.3 mg/l |
| 21 Jan 2025, 12:39 | 11.8 | 11.8 mg/l |
| 4 Oct 2024, 13:50 | 10.5 | 10.5 mg/l |
| 3 Jul 2024, 09:15 | 9.83 | 9.83 mg/l |
| 2 Apr 2024, 13:52 | 11.2 | 11.2 mg/l |
| 3 Jan 2024, 12:10 | 11.5 | 11.5 mg/l |
| 23 Oct 2023, 12:54 | 10.3 | 10.3 mg/l |
Water temperature
code 0076 · °C
6.5 °C
Sampled 14 Jan 2026, 9 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Jan 2026, 14:09 | 6.5 | 6.5 °C |
| 7 Oct 2025, 12:02 | 13.6 | 13.6 °C |
| 21 Jul 2025, 09:03 | 17.1 | 17.1 °C |
| 3 Apr 2025, 13:31 | 10.8 | 10.8 °C |
| 21 Jan 2025, 12:39 | 6.4 | 6.4 °C |
| 4 Oct 2024, 13:50 | 12 | 12 °C |
| 3 Jul 2024, 09:15 | 14.5 | 14.5 °C |
| 2 Apr 2024, 13:52 | 11.3 | 11.3 °C |
| 3 Jan 2024, 12:10 | 8.5 | 8.5 °C |
| 23 Oct 2023, 12:54 | 11.8 | 11.8 °C |
pH
code 0061
7.95
Sampled 14 Jan 2026, 9 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Jan 2026, 14:09 | 7.95 | 7.95 |
| 7 Oct 2025, 12:02 | 7.92 | 7.92 |
| 21 Jul 2025, 09:03 | 7.75 | 7.75 |
| 3 Apr 2025, 13:31 | 7.91 | 7.91 |
| 21 Jan 2025, 12:39 | 7.98 | 7.98 |
| 4 Oct 2024, 13:50 | 7.95 | 7.95 |
| 3 Jul 2024, 09:15 | 8.03 | 8.03 |
| 2 Apr 2024, 13:52 | 8.03 | 8.03 |
| 3 Jan 2024, 12:10 | 8.11 | 8.11 |
| 23 Oct 2023, 12:54 | 7.86 | 7.86 |
Conductivity
at 25 °C · code 0077 · µS/cm
764 µS/cm
Sampled 14 Jan 2026, 9 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 14 Jan 2026, 14:09 | 764 | 764 µS/cm |
| 7 Oct 2025, 12:02 | 739 | 739 µS/cm |
| 21 Jul 2025, 09:03 | 632 | 632 µS/cm |
| 3 Apr 2025, 13:31 | 777 | 777 µS/cm |
| 21 Jan 2025, 12:39 | 777 | 777 µS/cm |
| 4 Oct 2024, 13:50 | 614 | 614 µS/cm |
| 3 Jul 2024, 09:15 | 755 | 755 µS/cm |
| 2 Apr 2024, 13:52 | 713 | 713 µS/cm |
| 3 Jan 2024, 12:10 | 510 | 510 µS/cm |
| 23 Oct 2023, 12:54 | 638 | 638 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 | 10 | Oct 2023 – Jan 2026 | 94.4% 14 Jan 2026 |
| Oxygen, Dissolved as O2 9924 | River water | 10 | Oct 2023 – Jan 2026 | 11.6 mg/l 14 Jan 2026 |
| Temperature of Water 0076 | River water | 10 | Oct 2023 – Jan 2026 | 6.5 °C 14 Jan 2026 |
| pH 0061 | River water | 10 | Oct 2023 – Jan 2026 | 7.95 14 Jan 2026 |
| Conductivity at 25 C 0077 | River water | 10 | Oct 2023 – Jan 2026 | 764 µS/cm 14 Jan 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.