Claydon Brook Layby to A413 Bridge

EA name: CLAYDON BK. LAYBY TO A413 BR (also listed as “CLAYDON BK. LAYBY TO A413 BR SOUTH OF WINSLOW”)
Environment Agency sampling point AN-02M54 · 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
9 Sep 2026, 12:4622 days ago · time as the Environment Agency records it (UK clock time; the source gives no time zone)
Samples banked
4 since 1 Jun 2026 Imported periods: 1 Oct 2023 – 30 Sep 2026. Samples outside them are not shown here.
Latest sample
River / running surface water Environmental monitoring statutory (EU directives)
Where
National Grid 477659, 226769As published, to the nearest 1 m. Open in a map
River, by its own name
Claydon Brook
River, by the map
Claydon BrookPlaced on the river its name gives, 0 m from the line.
Next gauge downstream
THORNBOROUGH MILL SLUICE AUTOMATION 22 km along the riverThornborough On the River Great Ouse · 22 km along the river
Why it was sampled
Environmental monitoring statutory (EU directives) (4 samples)

Main measurements, river water

Dissolved oxygen

% saturation · code 9901 · %

90%

Sampled 9 Sep 2026, 22 days ago · 4 results banked

20406080100%2024202520261 Jun 2026, 09:54: 44.5%1 Jul 2026, 12:23: 37.5%18 Aug 2026, 12:26: 60.1%9 Sep 2026, 12:46: 90%
Every result (4)
SampledResult as publishedReads as
9 Sep 2026, 12:4690 90%
18 Aug 2026, 12:2660.1 60.1%
1 Jul 2026, 12:2337.5 37.5%
1 Jun 2026, 09:5444.5 44.5%

Dissolved oxygen

as O2 · code 9924 · mg/l

9.19 mg/l

Sampled 9 Sep 2026, 22 days ago · 4 results banked

246810mg/l2024202520261 Jun 2026, 09:54: 4.45 mg/l1 Jul 2026, 12:23: 3.61 mg/l18 Aug 2026, 12:26: 5.58 mg/l9 Sep 2026, 12:46: 9.19 mg/l
Every result (4)
SampledResult as publishedReads as
9 Sep 2026, 12:469.19 9.19 mg/l
18 Aug 2026, 12:265.58 5.58 mg/l
1 Jul 2026, 12:233.61 3.61 mg/l
1 Jun 2026, 09:544.45 4.45 mg/l

Water temperature

code 0076 · °C

14.3 °C

Sampled 9 Sep 2026, 22 days ago · 4 results banked

14161820°C2024202520261 Jun 2026, 09:54: 15.3 °C1 Jul 2026, 12:23: 17.1 °C18 Aug 2026, 12:26: 18.8 °C9 Sep 2026, 12:46: 14.3 °C
Every result (4)
SampledResult as publishedReads as
9 Sep 2026, 12:4614.3 14.3 °C
18 Aug 2026, 12:2618.8 18.8 °C
1 Jul 2026, 12:2317.1 17.1 °C
1 Jun 2026, 09:5415.3 15.3 °C

pH

code 0061

7.88

Sampled 9 Sep 2026, 22 days ago · 4 results banked

7.67.77.87.92024202520261 Jun 2026, 09:54: 7.791 Jul 2026, 12:23: 7.6418 Aug 2026, 12:26: 7.769 Sep 2026, 12:46: 7.88
Every result (4)
SampledResult as publishedReads as
9 Sep 2026, 12:467.88 7.88
18 Aug 2026, 12:267.76 7.76
1 Jul 2026, 12:237.64 7.64
1 Jun 2026, 09:547.79 7.79

Ammonia

ammoniacal nitrogen as N · code 0111 · mg/l

below 0.03 mg/l (not detected above this)

Sampled 9 Sep 2026, 22 days ago · 4 results banked

0.020.040.060.08mg/l2024202520261 Jun 2026, 09:54: 0.07 mg/l1 Jul 2026, 12:23: 0.046 mg/l18 Aug 2026, 12:26: below 0.03 mg/l (not detected above this)9 Sep 2026, 12:46: below 0.03 mg/l (not detected above this)
Every result (4)
SampledResult as publishedReads as
9 Sep 2026, 12:46<0.03 below 0.03 mg/l (not detected above this)
18 Aug 2026, 12:26<0.03 below 0.03 mg/l (not detected above this)
1 Jul 2026, 12:230.046 0.046 mg/l
1 Jun 2026, 09:540.07 0.07 mg/l

Nitrate

as nitrogen (N) · code 0117 · mg/l

6.99 mg/l

Sampled 9 Sep 2026, 22 days ago · 4 results banked

34567mg/l2024202520261 Jun 2026, 09:54: 5.94 mg/l1 Jul 2026, 12:23: 5.56 mg/l18 Aug 2026, 12:26: 3.89 mg/l9 Sep 2026, 12:46: 6.99 mg/l
Every result (4)
SampledResult as publishedReads as
9 Sep 2026, 12:466.99 6.99 mg/l
18 Aug 2026, 12:263.89 3.89 mg/l
1 Jul 2026, 12:235.56 5.56 mg/l
1 Jun 2026, 09:545.94 5.94 mg/l

Phosphate

orthophosphate, reactive, as P · code 0180 · mg/l

1.3 mg/l

Sampled 9 Sep 2026, 22 days ago · 4 results banked

11.11.21.3mg/l2024202520261 Jun 2026, 09:54: 1 mg/l1 Jul 2026, 12:23: 1.3 mg/l18 Aug 2026, 12:26: 1.1 mg/l9 Sep 2026, 12:46: 1.3 mg/l
Every result (4)
SampledResult as publishedReads as
9 Sep 2026, 12:461.3 1.3 mg/l
18 Aug 2026, 12:261.1 1.1 mg/l
1 Jul 2026, 12:231.3 1.3 mg/l
1 Jun 2026, 09:541 1 mg/l

Conductivity

at 25 °C · code 0077 · µS/cm

908 µS/cm

Sampled 9 Sep 2026, 22 days ago · 4 results banked

700750800850900950µS/cm2024202520261 Jun 2026, 09:54: 849 µS/cm1 Jul 2026, 12:23: 843 µS/cm18 Aug 2026, 12:26: 745 µS/cm9 Sep 2026, 12:46: 908 µS/cm
Every result (4)
SampledResult as publishedReads as
9 Sep 2026, 12:46908 908 µS/cm
18 Aug 2026, 12:26745 745 µS/cm
1 Jul 2026, 12:23843 843 µS/cm
1 Jun 2026, 09:54849 849 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
DeterminandMaterialResults First – lastLatest result
Oxygen, Dissolved, % Saturation 9901 River water 4 Jun 2026 – Sep 2026 90% 9 Sep 2026
Oxygen, Dissolved as O2 9924 River water 4 Jun 2026 – Sep 2026 9.19 mg/l 9 Sep 2026
Temperature of Water 0076 River water 4 Jun 2026 – Sep 2026 14.3 °C 9 Sep 2026
pH 0061 River water 4 Jun 2026 – Sep 2026 7.88 9 Sep 2026
Ammoniacal Nitrogen as N 0111 River water 4 Jun 2026 – Sep 2026 below 0.03 mg/l 9 Sep 2026
Nitrate as N 0117 River water 4 Jun 2026 – Sep 2026 6.99 mg/l 9 Sep 2026
Orthophosphate, reactive as P 0180 River water 4 Jun 2026 – Sep 2026 1.3 mg/l 9 Sep 2026
Conductivity at 25 C 0077 River water 4 Jun 2026 – Sep 2026 908 µS/cm 9 Sep 2026
Alkalinity to pH 4.5 as CaCO3 0162 River water 4 Jun 2026 – Sep 2026 240 mg/l 9 Sep 2026
Ammonia un-ionised as N 0119 River water 4 Jun 2026 – Sep 2026 below 0.00057 mg/l 9 Sep 2026
Nitrite as N 0118 River water 4 Jun 2026 – Sep 2026 0.012 mg/l 9 Sep 2026
Nitrogen, Total Oxidised as N 0116 River water 4 Jun 2026 – Sep 2026 7 mg/l 9 Sep 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.