3.6 km downstream of High Halden sewage treatment works
EA name: 3.6KM D/S HIGH HALDEN STW (also listed as “HIGH HALDEN STREAM UPSTREAM OF RIVER BEULT CONFLUENCE, 3.6KM DOWNSTREAM OF HIGH HALDEN SEWAGE TREATMENT WORKS”)
Environment Agency sampling point SO-E0000616 · 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
- 5 Mar 2025, 10:2219 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 11 Jun 2024 Imported periods: 1 Oct 2023 – 8 Oct 2026. Samples outside them are not shown here.
- Latest sample
- River / running surface water Environmental monitoring statutory (EU directives)
- Where
- National Grid 590264, 140155As published, to the nearest 1 m. Open in a map
- River, by its own name
- High Halden Stream
- River, by the map
- An unnamed streamPlaced by position alone (the only river line close by), 4 m from the line.
- Next gauge downstream
- Smarden On the River Beult · 6.1 km along the river
- Why it was sampled
- Environmental monitoring statutory (EU directives) (10 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
90.4%
Sampled 5 Mar 2025, 19 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Mar 2025, 10:22 | 90.4 | 90.4% |
| 4 Feb 2025, 11:08 | 88.6 | 88.6% |
| 14 Jan 2025, 11:55 | 85 | 85% |
| 13 Dec 2024, 12:43 | 84.1 | 84.1% |
| 5 Nov 2024, 11:07 | 63.9 | 63.9% |
| 17 Oct 2024, 10:17 | 66.4 | 66.4% |
| 5 Sep 2024, 13:18 | 56.9 | 56.9% |
| 8 Aug 2024, 08:40 | 60.3 | 60.3% |
| 15 Jul 2024, 09:30 | 64.4 | 64.4% |
| 11 Jun 2024, 10:47 | 66.8 | 66.8% |
Dissolved oxygen
as O2 · code 9924 · mg/l
12.1 mg/l
Sampled 5 Mar 2025, 19 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Mar 2025, 10:22 | 12.1 | 12.1 mg/l |
| 4 Feb 2025, 11:08 | 11.2 | 11.2 mg/l |
| 14 Jan 2025, 11:55 | 11.6 | 11.6 mg/l |
| 13 Dec 2024, 12:43 | 10.2 | 10.2 mg/l |
| 5 Nov 2024, 11:07 | 6.98 | 6.98 mg/l |
| 17 Oct 2024, 10:17 | 6.74 | 6.74 mg/l |
| 5 Sep 2024, 13:18 | 5.58 | 5.58 mg/l |
| 8 Aug 2024, 08:40 | 6.03 | 6.03 mg/l |
| 15 Jul 2024, 09:30 | 6.66 | 6.66 mg/l |
| 11 Jun 2024, 10:47 | 7.35 | 7.35 mg/l |
Water temperature
code 0076 · °C
3.3 °C
Sampled 5 Mar 2025, 19 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Mar 2025, 10:22 | 3.3 | 3.3 °C |
| 4 Feb 2025, 11:08 | 5.3 | 5.3 °C |
| 14 Jan 2025, 11:55 | 2.5 | 2.5 °C |
| 13 Dec 2024, 12:43 | 7 | 7 °C |
| 5 Nov 2024, 11:07 | 11.3 | 11.3 °C |
| 17 Oct 2024, 10:17 | 14.6 | 14.6 °C |
| 5 Sep 2024, 13:18 | 16.2 | 16.2 °C |
| 8 Aug 2024, 08:40 | 15.3 | 15.3 °C |
| 15 Jul 2024, 09:30 | 13.7 | 13.7 °C |
| 11 Jun 2024, 10:47 | 11 | 11 °C |
pH
code 0061
7.7
Sampled 5 Mar 2025, 19 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Mar 2025, 10:22 | 7.7 | 7.7 |
| 4 Feb 2025, 11:08 | 7.54 | 7.54 |
| 14 Jan 2025, 11:55 | 7.46 | 7.46 |
| 13 Dec 2024, 12:43 | 7.59 | 7.59 |
| 5 Nov 2024, 11:07 | 7.34 | 7.34 |
| 17 Oct 2024, 10:17 | 7.05 | 7.05 |
| 5 Sep 2024, 13:18 | 7.46 | 7.46 |
| 8 Aug 2024, 08:40 | 7.47 | 7.47 |
| 15 Jul 2024, 09:30 | 7.73 | 7.73 |
| 11 Jun 2024, 10:47 | 7.65 | 7.65 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
0.13 mg/l
Sampled 5 Mar 2025, 19 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Mar 2025, 10:22 | 0.13 | 0.13 mg/l |
| 4 Feb 2025, 11:08 | 0.12 | 0.12 mg/l |
| 14 Jan 2025, 11:55 | 0.22 | 0.22 mg/l |
| 13 Dec 2024, 12:43 | 0.082 | 0.082 mg/l |
| 5 Nov 2024, 11:07 | 0.044 | 0.044 mg/l |
| 17 Oct 2024, 10:17 | 0.11 | 0.11 mg/l |
| 5 Sep 2024, 13:18 | 0.052 | 0.052 mg/l |
| 8 Aug 2024, 08:40 | 0.07 | 0.07 mg/l |
| 15 Jul 2024, 09:30 | 0.12 | 0.12 mg/l |
| 11 Jun 2024, 10:47 | 0.05 | 0.05 mg/l |
Nitrate
as nitrogen (N) · code 0117 · mg/l
1.58 mg/l
Sampled 5 Mar 2025, 19 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Mar 2025, 10:22 | 1.58 | 1.58 mg/l |
| 4 Feb 2025, 11:08 | 1.48 | 1.48 mg/l |
| 14 Jan 2025, 11:55 | 1.68 | 1.68 mg/l |
| 13 Dec 2024, 12:43 | 2.46 | 2.46 mg/l |
| 5 Nov 2024, 11:07 | 5.95 | 5.95 mg/l |
| 17 Oct 2024, 10:17 | 1.87 | 1.87 mg/l |
| 5 Sep 2024, 13:18 | 22.9 | 22.9 mg/l |
| 8 Aug 2024, 08:40 | 26 | 26 mg/l |
| 15 Jul 2024, 09:30 | 11.9 | 11.9 mg/l |
| 11 Jun 2024, 10:47 | 16 | 16 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.19 mg/l
Sampled 5 Mar 2025, 19 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Mar 2025, 10:22 | 0.19 | 0.19 mg/l |
| 4 Feb 2025, 11:08 | 0.2 | 0.2 mg/l |
| 14 Jan 2025, 11:55 | 0.2 | 0.2 mg/l |
| 13 Dec 2024, 12:43 | 0.23 | 0.23 mg/l |
| 5 Nov 2024, 11:07 | 0.22 | 0.22 mg/l |
| 17 Oct 2024, 10:17 | 0.34 | 0.34 mg/l |
| 5 Sep 2024, 13:18 | 0.36 | 0.36 mg/l |
| 8 Aug 2024, 08:40 | 0.25 | 0.25 mg/l |
| 15 Jul 2024, 09:30 | 0.31 | 0.31 mg/l |
| 11 Jun 2024, 10:47 | 0.24 | 0.24 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
553 µS/cm
Sampled 5 Mar 2025, 19 months ago · 10 results banked
Every result (10)
| Sampled | Result as published | Reads as |
|---|---|---|
| 5 Mar 2025, 10:22 | 553 | 553 µS/cm |
| 4 Feb 2025, 11:08 | 496 | 496 µS/cm |
| 14 Jan 2025, 11:55 | 504 | 504 µS/cm |
| 13 Dec 2024, 12:43 | 474 | 474 µS/cm |
| 5 Nov 2024, 11:07 | 713 | 713 µS/cm |
| 17 Oct 2024, 10:17 | 403 | 403 µS/cm |
| 5 Sep 2024, 13:18 | 928 | 928 µS/cm |
| 8 Aug 2024, 08:40 | 979 | 979 µS/cm |
| 15 Jul 2024, 09:30 | 837 | 837 µS/cm |
| 11 Jun 2024, 10:47 | 924 | 924 µS/cm |
Everything measured here
12 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 12 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 10 | Jun 2024 – Mar 2025 | 90.4% 5 Mar 2025 |
| Oxygen, Dissolved as O2 9924 | River water | 10 | Jun 2024 – Mar 2025 | 12.1 mg/l 5 Mar 2025 |
| Temperature of Water 0076 | River water | 10 | Jun 2024 – Mar 2025 | 3.3 °C 5 Mar 2025 |
| pH 0061 | River water | 10 | Jun 2024 – Mar 2025 | 7.7 5 Mar 2025 |
| Ammoniacal Nitrogen as N 0111 | River water | 10 | Jun 2024 – Mar 2025 | 0.13 mg/l 5 Mar 2025 |
| Nitrate as N 0117 | River water | 10 | Jun 2024 – Mar 2025 | 1.58 mg/l 5 Mar 2025 |
| Orthophosphate, reactive as P 0180 | River water | 10 | Jun 2024 – Mar 2025 | 0.19 mg/l 5 Mar 2025 |
| Conductivity at 25 C 0077 | River water | 10 | Jun 2024 – Mar 2025 | 553 µS/cm 5 Mar 2025 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 10 | Jun 2024 – Mar 2025 | 140 mg/l 5 Mar 2025 |
| Ammonia un-ionised as N 0119 | River water | 10 | Jun 2024 – Mar 2025 | 0.00073 mg/l 5 Mar 2025 |
| Nitrite as N 0118 | River water | 10 | Jun 2024 – Mar 2025 | 0.018 mg/l 5 Mar 2025 |
| Nitrogen, Total Oxidised as N 0116 | River water | 10 | Jun 2024 – Mar 2025 | 1.6 mg/l 5 Mar 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.