River Stour at Longham
EA name: RIVER STOUR AT LONGHAM
Environment Agency sampling point SW-50370369 · 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
- 4 Sep 2026, 09:4353 days ago · time as the Environment Agency records it (UK clock time; the source gives no time zone)
- Samples banked
- 7 since 12 Jan 2024 Imported periods: 1 Oct 2023 – 27 Oct 2026. Samples outside them are not shown here.
- Latest sample
- River / running surface water Environmental monitoring statutory (EU directives) · results completed 10 Sep 2026
- Where
- National Grid 406383, 97290As published, to the nearest 1 m. Open in a map
- River, by its own name
- Stour
- River, by the map
- River StourPlaced on the river its name gives, 0 m from the line.
- Next gauge downstream
- Throop On the River Stour · 7.7 km along the river
- Nearest gauge upstream
- Wimborne On the River Stour · 8.5 km along the river
- Why it was sampled
- Environmental monitoring statutory (EU directives) (6 samples)
Statutory failures (follow ups at non-designated points) (1 samples)
Results here were completed a median of 6 days after the sample was taken (4 to 15 days, 3 samples).
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
90.3%
Sampled 4 Sep 2026, 53 days ago · 6 results banked
Every result (6)
| Sampled | Result as published | Reads as |
|---|---|---|
| 4 Sep 2026, 09:43 | 90.3 | 90.3% |
| 11 Aug 2026, 12:10 | 105.5 | 105.5% |
| 3 Jul 2026, 08:25 | 105.1 | 105.1% |
| 4 Jun 2026, 09:27 | 95.7 | 95.7% |
| 11 May 2026, 11:22 | 102.6 | 102.6% |
| 16 Apr 2026, 08:47 | 100 | 100% |
Dissolved oxygen
as O2 · code 9924 · mg/l
8.36 mg/l
Sampled 4 Sep 2026, 53 days ago · 6 results banked
Every result (6)
| Sampled | Result as published | Reads as |
|---|---|---|
| 4 Sep 2026, 09:43 | 8.36 | 8.36 mg/l |
| 11 Aug 2026, 12:10 | 9.44 | 9.44 mg/l |
| 3 Jul 2026, 08:25 | 9.86 | 9.86 mg/l |
| 4 Jun 2026, 09:27 | 9.48 | 9.48 mg/l |
| 11 May 2026, 11:22 | 10.6 | 10.6 mg/l |
| 16 Apr 2026, 08:47 | 10.8 | 10.8 mg/l |
Water temperature
code 0076 · °C
19 °C
Sampled 4 Sep 2026, 53 days ago · 6 results banked
Every result (6)
| Sampled | Result as published | Reads as |
|---|---|---|
| 4 Sep 2026, 09:43 | 19 | 19 °C |
| 11 Aug 2026, 12:10 | 20.7 | 20.7 °C |
| 3 Jul 2026, 08:25 | 18.3 | 18.3 °C |
| 4 Jun 2026, 09:27 | 15.7 | 15.7 °C |
| 11 May 2026, 11:22 | 13.8 | 13.8 °C |
| 16 Apr 2026, 08:47 | 11.9 | 11.9 °C |
pH
code 0061
8.35
Sampled 4 Sep 2026, 53 days ago · 6 results banked
Every result (6)
| Sampled | Result as published | Reads as |
|---|---|---|
| 4 Sep 2026, 09:43 | 8.35 | 8.35 |
| 11 Aug 2026, 12:10 | 8.16 | 8.16 |
| 3 Jul 2026, 08:25 | 8.31 | 8.31 |
| 4 Jun 2026, 09:27 | 8.04 | 8.04 |
| 11 May 2026, 11:22 | 8.3 | 8.3 |
| 16 Apr 2026, 08:47 | 8.2 | 8.2 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
0.038 mg/l
Sampled 4 Sep 2026, 53 days ago · 6 results banked
Every result (6)
| Sampled | Result as published | Reads as |
|---|---|---|
| 4 Sep 2026, 09:43 | 0.038 | 0.038 mg/l |
| 11 Aug 2026, 12:10 | 0.039 | 0.039 mg/l |
| 3 Jul 2026, 08:25 | <0.03 | below 0.03 mg/l (not detected above this) |
| 4 Jun 2026, 09:27 | 0.06 | 0.06 mg/l |
| 11 May 2026, 11:22 | <0.03 | below 0.03 mg/l (not detected above this) |
| 16 Apr 2026, 08:47 | <0.03 | below 0.03 mg/l (not detected above this) |
Nitrate
as nitrogen (N) · code 0117 · mg/l
7.05 mg/l
Sampled 4 Sep 2026, 53 days ago · 6 results banked
Every result (6)
| Sampled | Result as published | Reads as |
|---|---|---|
| 4 Sep 2026, 09:43 | 7.05 | 7.05 mg/l |
| 11 Aug 2026, 12:10 | 5.85 | 5.85 mg/l |
| 3 Jul 2026, 08:25 | 6.66 | 6.66 mg/l |
| 4 Jun 2026, 09:27 | 6.94 | 6.94 mg/l |
| 11 May 2026, 11:22 | 7.96 | 7.96 mg/l |
| 16 Apr 2026, 08:47 | 8.19 | 8.19 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.12 mg/l
Sampled 4 Sep 2026, 53 days ago · 6 results banked
Every result (6)
| Sampled | Result as published | Reads as |
|---|---|---|
| 4 Sep 2026, 09:43 | 0.12 | 0.12 mg/l |
| 11 Aug 2026, 12:10 | 0.088 | 0.088 mg/l |
| 3 Jul 2026, 08:25 | 0.065 | 0.065 mg/l |
| 4 Jun 2026, 09:27 | 0.07 | 0.07 mg/l |
| 11 May 2026, 11:22 | 0.019 | 0.019 mg/l |
| 16 Apr 2026, 08:47 | 0.033 | 0.033 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
673 µS/cm
Sampled 4 Sep 2026, 53 days ago · 6 results banked
Every result (6)
| Sampled | Result as published | Reads as |
|---|---|---|
| 4 Sep 2026, 09:43 | 673 | 673 µS/cm |
| 11 Aug 2026, 12:10 | 608 | 608 µS/cm |
| 3 Jul 2026, 08:25 | 595 | 595 µS/cm |
| 4 Jun 2026, 09:27 | 574 | 574 µS/cm |
| 11 May 2026, 11:22 | 575 | 575 µS/cm |
| 16 Apr 2026, 08:47 | 597 | 597 µS/cm |
Everything measured here
20 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 20 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 6 | Apr 2026 – Sep 2026 | 90.3% 4 Sep 2026 |
| Oxygen, Dissolved as O2 9924 | River water | 6 | Apr 2026 – Sep 2026 | 8.36 mg/l 4 Sep 2026 |
| Temperature of Water 0076 | River water | 6 | Apr 2026 – Sep 2026 | 19 °C 4 Sep 2026 |
| pH 0061 | River water | 6 | Apr 2026 – Sep 2026 | 8.35 4 Sep 2026 |
| Ammoniacal Nitrogen as N 0111 | River water | 6 | Apr 2026 – Sep 2026 | 0.038 mg/l 4 Sep 2026 |
| Nitrate as N 0117 | River water | 6 | Apr 2026 – Sep 2026 | 7.05 mg/l 4 Sep 2026 |
| Orthophosphate, reactive as P 0180 | River water | 6 | Apr 2026 – Sep 2026 | 0.12 mg/l 4 Sep 2026 |
| Conductivity at 25 C 0077 | River water | 6 | Apr 2026 – Sep 2026 | 673 µS/cm 4 Sep 2026 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 6 | Apr 2026 – Sep 2026 | 220 mg/l 4 Sep 2026 |
| Aluminium 6057 | River water | 1 | Jan 2024 – Jan 2024 | 78 µg/l 12 Jan 2024 |
| Ammonia un-ionised as N 0119 | River water | 6 | Apr 2026 – Sep 2026 | 0.00133 mg/l 4 Sep 2026 |
| Cadmium 0108 | River water | 1 | Jan 2024 – Jan 2024 | below 0.1 µg/l 12 Jan 2024 |
| Chromium 3164 | River water | 1 | Jan 2024 – Jan 2024 | below 0.5 µg/l 12 Jan 2024 |
| Copper 6452 | River water | 1 | Jan 2024 – Jan 2024 | 1.2 µg/l 12 Jan 2024 |
| Iron, Dissolved 6460 | River water | 1 | Jan 2024 – Jan 2024 | below 30 µg/l 12 Jan 2024 |
| Lead 0050 | River water | 1 | Jan 2024 – Jan 2024 | below 2 µg/l 12 Jan 2024 |
| Nickel 6462 | River water | 1 | Jan 2024 – Jan 2024 | 2 µg/l 12 Jan 2024 |
| Nitrite as N 0118 | River water | 6 | Apr 2026 – Sep 2026 | 0.054 mg/l 4 Sep 2026 |
| Nitrogen, Total Oxidised as N 0116 | River water | 6 | Apr 2026 – Sep 2026 | 7.1 mg/l 4 Sep 2026 |
| Zinc 6455 | River water | 1 | Jan 2024 – Jan 2024 | below 5 µg/l 12 Jan 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.