Catchwater Drain upstream of Mareham Le Fen sewage treatment works
EA name: CATCHWATER DRAIN U/S MAREHAM LE FEN STW
Environment Agency sampling point AN-CTWTRMLF · 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
- 16 Dec 2025, 11:339 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 30 Sep 2026 and had nothing newer.
- Samples banked
- 22 since 23 Oct 2023 Imported periods: 1 Oct 2023 – 30 Sep 2026. Samples outside them are not shown here.
- Latest sample
- River / running surface water Monitoring (national agency policy)
- Where
- National Grid 527837, 359266As published, to the nearest 1 m. Open in a map
- River, by its own name
- Catchwater Drain
- River, by the map
- Catchwater DrainPlaced on the river its name gives, 5 m from the line.
- Next gauge downstream
- Revesby On the West Fen Catchwater Drain · 3.5 km along the river
- Nearest gauge upstream
- New York On the West Fen Catchwater Drain · 5.4 km along the river
- Why it was sampled
- Monitoring (national agency policy) (22 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
81.7%
Sampled 16 Dec 2025, 9 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 16 Dec 2025, 11:33 | 81.7 | 81.7% |
| 3 Dec 2025, 11:05 | 70.1 | 70.1% |
| 20 Nov 2025, 11:51 | 88.6 | 88.6% |
| 4 Nov 2025, 11:50 | 75.7 | 75.7% |
| 24 Mar 2025, 11:37 | 93.2 | 93.2% |
| 14 Feb 2025, 08:28 | 91.2 | 91.2% |
| 24 Jan 2025, 10:31 | 103.1 | 103.1% |
| 5 Dec 2024, 10:43 | 97.7 | 97.7% |
| 20 Nov 2024, 11:38 | 101.9 | 101.9% |
| 23 Oct 2024, 11:13 | 100.3 | 100.3% |
| 18 Sep 2024, 10:10 | 88.5 | 88.5% |
| 21 Aug 2024, 09:53 | 55.2 | 55.2% |
| 16 Jul 2024, 11:46 | 82.1 | 82.1% |
| 17 Jun 2024, 11:49 | 77.2 | 77.2% |
| 17 May 2024, 11:07 | 92.4 | 92.4% |
| 16 Apr 2024, 10:49 | 99.4 | 99.4% |
| 19 Mar 2024, 10:35 | 100.8 | 100.8% |
| 20 Feb 2024, 10:58 | 83.3 | 83.3% |
| 15 Jan 2024, 11:08 | 89.3 | 89.3% |
| 6 Dec 2023, 11:46 | 92.3 | 92.3% |
| 20 Nov 2023, 10:56 | 92.6 | 92.6% |
| 23 Oct 2023, 11:11 | 83.1 | 83.1% |
Dissolved oxygen
as O2 · code 9924 · mg/l
9.45 mg/l
Sampled 16 Dec 2025, 9 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 16 Dec 2025, 11:33 | 9.45 | 9.45 mg/l |
| 3 Dec 2025, 11:05 | 8.67 | 8.67 mg/l |
| 20 Nov 2025, 11:51 | 11.1 | 11.1 mg/l |
| 4 Nov 2025, 11:50 | 8.08 | 8.08 mg/l |
| 24 Mar 2025, 11:37 | 10.1 | 10.1 mg/l |
| 14 Feb 2025, 08:28 | 12.1 | 12.1 mg/l |
| 24 Jan 2025, 10:31 | 12.7 | 12.7 mg/l |
| 5 Dec 2024, 10:43 | 11.3 | 11.3 mg/l |
| 20 Nov 2024, 11:38 | 13.4 | 13.4 mg/l |
| 23 Oct 2024, 11:13 | 11.1 | 11.1 mg/l |
| 18 Sep 2024, 10:10 | 9.16 | 9.16 mg/l |
| 21 Aug 2024, 09:53 | 5.58 | 5.58 mg/l |
| 16 Jul 2024, 11:46 | 8.19 | 8.19 mg/l |
| 17 Jun 2024, 11:49 | 7.52 | 7.52 mg/l |
| 17 May 2024, 11:07 | 8.89 | 8.89 mg/l |
| 16 Apr 2024, 10:49 | 11.4 | 11.4 mg/l |
| 19 Mar 2024, 10:35 | 11.2 | 11.2 mg/l |
| 20 Feb 2024, 10:58 | 9.8 | 9.8 mg/l |
| 15 Jan 2024, 11:08 | 12.4 | 12.4 mg/l |
| 6 Dec 2023, 11:46 | 11.8 | 11.8 mg/l |
| 20 Nov 2023, 10:56 | 10.6 | 10.6 mg/l |
| 23 Oct 2023, 11:11 | 9.14 | 9.14 mg/l |
Water temperature
code 0076 · °C
8.9 °C
Sampled 16 Dec 2025, 9 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 16 Dec 2025, 11:33 | 8.9 | 8.9 °C |
| 3 Dec 2025, 11:05 | 6.2 | 6.2 °C |
| 20 Nov 2025, 11:51 | 5.7 | 5.7 °C |
| 4 Nov 2025, 11:50 | 12.3 | 12.3 °C |
| 24 Mar 2025, 11:37 | 11.7 | 11.7 °C |
| 14 Feb 2025, 08:28 | 3.4 | 3.4 °C |
| 24 Jan 2025, 10:31 | 6.5 | 6.5 °C |
| 5 Dec 2024, 10:43 | 8.8 | 8.8 °C |
| 20 Nov 2024, 11:38 | 3.7 | 3.7 °C |
| 23 Oct 2024, 11:13 | 10.9 | 10.9 °C |
| 18 Sep 2024, 10:10 | 13.7 | 13.7 °C |
| 21 Aug 2024, 09:53 | 14.8 | 14.8 °C |
| 16 Jul 2024, 11:46 | 15.4 | 15.4 °C |
| 17 Jun 2024, 11:49 | 16.5 | 16.5 °C |
| 17 May 2024, 11:07 | 17.1 | 17.1 °C |
| 16 Apr 2024, 10:49 | 9.4 | 9.4 °C |
| 19 Mar 2024, 10:35 | 10.6 | 10.6 °C |
| 20 Feb 2024, 10:58 | 8.2 | 8.2 °C |
| 15 Jan 2024, 11:08 | 1.8 | 1.8 °C |
| 6 Dec 2023, 11:46 | 4.9 | 4.9 °C |
| 20 Nov 2023, 10:56 | 9.5 | 9.5 °C |
| 23 Oct 2023, 11:11 | 11 | 11 °C |
pH
code 0061
7.55
Sampled 16 Dec 2025, 9 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 16 Dec 2025, 11:33 | 7.55 | 7.55 |
| 3 Dec 2025, 11:05 | 7.61 | 7.61 |
| 20 Nov 2025, 11:51 | 7.76 | 7.76 |
| 4 Nov 2025, 11:50 | 7.51 | 7.51 |
| 24 Mar 2025, 11:37 | 8.23 | 8.23 |
| 14 Feb 2025, 08:28 | 8 | 8 |
| 24 Jan 2025, 10:31 | 8.31 | 8.31 |
| 5 Dec 2024, 10:43 | 8.03 | 8.03 |
| 20 Nov 2024, 11:38 | 8.28 | 8.28 |
| 23 Oct 2024, 11:13 | 8.1 | 8.1 |
| 18 Sep 2024, 10:10 | 7.64 | 7.64 |
| 21 Aug 2024, 09:53 | 7.88 | 7.88 |
| 16 Jul 2024, 11:46 | 7.8 | 7.8 |
| 17 Jun 2024, 11:49 | 7.84 | 7.84 |
| 17 May 2024, 11:07 | 7.69 | 7.69 |
| 16 Apr 2024, 10:49 | 8.29 | 8.29 |
| 19 Mar 2024, 10:35 | 8.09 | 8.09 |
| 20 Feb 2024, 10:58 | 7.49 | 7.49 |
| 15 Jan 2024, 11:08 | 7.87 | 7.87 |
| 6 Dec 2023, 11:46 | 7.86 | 7.86 |
| 20 Nov 2023, 10:56 | 7.92 | 7.92 |
| 23 Oct 2023, 11:11 | 7.53 | 7.53 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
0.13 mg/l
Sampled 16 Dec 2025, 9 months ago · 21 results banked
Every result (21)
| Sampled | Result as published | Reads as |
|---|---|---|
| 16 Dec 2025, 11:33 | 0.13 | 0.13 mg/l |
| 3 Dec 2025, 11:05 | <0.03 | below 0.03 mg/l (not detected above this) |
| 20 Nov 2025, 11:51 | 0.033 | 0.033 mg/l |
| 4 Nov 2025, 11:50 | 0.66 | 0.66 mg/l |
| 24 Mar 2025, 11:37 | <0.03 | below 0.03 mg/l (not detected above this) |
| 14 Feb 2025, 08:28 | 0.16 | 0.16 mg/l |
| 24 Jan 2025, 10:31 | 0.065 | 0.065 mg/l |
| 20 Nov 2024, 11:38 | <0.03 | below 0.03 mg/l (not detected above this) |
| 23 Oct 2024, 11:13 | <0.03 | below 0.03 mg/l (not detected above this) |
| 18 Sep 2024, 10:10 | 0.051 | 0.051 mg/l |
| 21 Aug 2024, 09:53 | 0.19 | 0.19 mg/l |
| 16 Jul 2024, 11:46 | 0.1 | 0.1 mg/l |
| 17 Jun 2024, 11:49 | 0.11 | 0.11 mg/l |
| 17 May 2024, 11:07 | 0.098 | 0.098 mg/l |
| 16 Apr 2024, 10:49 | <0.03 | below 0.03 mg/l (not detected above this) |
| 19 Mar 2024, 10:35 | <0.03 | below 0.03 mg/l (not detected above this) |
| 20 Feb 2024, 10:58 | 0.042 | 0.042 mg/l |
| 15 Jan 2024, 11:08 | 0.096 | 0.096 mg/l |
| 6 Dec 2023, 11:46 | <0.03 | below 0.03 mg/l (not detected above this) |
| 20 Nov 2023, 10:56 | <0.03 | below 0.03 mg/l (not detected above this) |
| 23 Oct 2023, 11:11 | <0.03 | below 0.03 mg/l (not detected above this) |
Nitrate
as nitrogen (N) · code 0117 · mg/l
11 mg/l
Sampled 16 Dec 2025, 9 months ago · 21 results banked
Every result (21)
| Sampled | Result as published | Reads as |
|---|---|---|
| 16 Dec 2025, 11:33 | 11 | 11 mg/l |
| 3 Dec 2025, 11:05 | 25.9 | 25.9 mg/l |
| 20 Nov 2025, 11:51 | 15 | 15 mg/l |
| 4 Nov 2025, 11:50 | 6.56 | 6.56 mg/l |
| 24 Mar 2025, 11:37 | 4.79 | 4.79 mg/l |
| 14 Feb 2025, 08:28 | 16.9 | 16.9 mg/l |
| 24 Jan 2025, 10:31 | 17.9 | 17.9 mg/l |
| 20 Nov 2024, 11:38 | 12 | 12 mg/l |
| 23 Oct 2024, 11:13 | 17 | 17 mg/l |
| 18 Sep 2024, 10:10 | 0.669 | 0.669 mg/l |
| 21 Aug 2024, 09:53 | 6.43 | 6.43 mg/l |
| 16 Jul 2024, 11:46 | 4.43 | 4.43 mg/l |
| 17 Jun 2024, 11:49 | 6.48 | 6.48 mg/l |
| 17 May 2024, 11:07 | 4.34 | 4.34 mg/l |
| 16 Apr 2024, 10:49 | 8.17 | 8.17 mg/l |
| 19 Mar 2024, 10:35 | 9.59 | 9.59 mg/l |
| 20 Feb 2024, 10:58 | 16 | 16 mg/l |
| 15 Jan 2024, 11:08 | 16 | 16 mg/l |
| 6 Dec 2023, 11:46 | 14 | 14 mg/l |
| 20 Nov 2023, 10:56 | 17 | 17 mg/l |
| 23 Oct 2023, 11:11 | 18 | 18 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.15 mg/l
Sampled 16 Dec 2025, 9 months ago · 21 results banked
Every result (21)
| Sampled | Result as published | Reads as |
|---|---|---|
| 16 Dec 2025, 11:33 | 0.15 | 0.15 mg/l |
| 3 Dec 2025, 11:05 | 0.027 | 0.027 mg/l |
| 20 Nov 2025, 11:51 | 0.044 | 0.044 mg/l |
| 4 Nov 2025, 11:50 | 0.94 | 0.94 mg/l |
| 24 Mar 2025, 11:37 | 0.014 | 0.014 mg/l |
| 14 Feb 2025, 08:28 | 0.015 | 0.015 mg/l |
| 24 Jan 2025, 10:31 | 0.018 | 0.018 mg/l |
| 20 Nov 2024, 11:38 | 0.033 | 0.033 mg/l |
| 23 Oct 2024, 11:13 | 0.016 | 0.016 mg/l |
| 18 Sep 2024, 10:10 | 0.25 | 0.25 mg/l |
| 21 Aug 2024, 09:53 | 0.038 | 0.038 mg/l |
| 16 Jul 2024, 11:46 | 0.14 | 0.14 mg/l |
| 17 Jun 2024, 11:49 | 0.02 | 0.02 mg/l |
| 17 May 2024, 11:07 | 0.013 | 0.013 mg/l |
| 16 Apr 2024, 10:49 | <0.01 | below 0.01 mg/l (not detected above this) |
| 19 Mar 2024, 10:35 | 0.019 | 0.019 mg/l |
| 20 Feb 2024, 10:58 | 0.067 | 0.067 mg/l |
| 15 Jan 2024, 11:08 | 0.039 | 0.039 mg/l |
| 6 Dec 2023, 11:46 | 0.031 | 0.031 mg/l |
| 20 Nov 2023, 10:56 | 0.027 | 0.027 mg/l |
| 23 Oct 2023, 11:11 | 0.084 | 0.084 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
578 µS/cm
Sampled 16 Dec 2025, 9 months ago · 22 results banked
Every result (22)
| Sampled | Result as published | Reads as |
|---|---|---|
| 16 Dec 2025, 11:33 | 578 | 578 µS/cm |
| 3 Dec 2025, 11:05 | 924 | 924 µS/cm |
| 20 Nov 2025, 11:51 | 809 | 809 µS/cm |
| 4 Nov 2025, 11:50 | 796 | 796 µS/cm |
| 24 Mar 2025, 11:37 | 703 | 703 µS/cm |
| 14 Feb 2025, 08:28 | 846 | 846 µS/cm |
| 24 Jan 2025, 10:31 | 873 | 873 µS/cm |
| 5 Dec 2024, 10:43 | 723 | 723 µS/cm |
| 20 Nov 2024, 11:38 | 725 | 725 µS/cm |
| 23 Oct 2024, 11:13 | 744 | 744 µS/cm |
| 18 Sep 2024, 10:10 | 797 | 797 µS/cm |
| 21 Aug 2024, 09:53 | 750 | 750 µS/cm |
| 16 Jul 2024, 11:46 | 561 | 561 µS/cm |
| 17 Jun 2024, 11:49 | 702 | 702 µS/cm |
| 17 May 2024, 11:07 | 615 | 615 µS/cm |
| 16 Apr 2024, 10:49 | 720 | 720 µS/cm |
| 19 Mar 2024, 10:35 | 663 | 663 µS/cm |
| 20 Feb 2024, 10:58 | 726 | 726 µS/cm |
| 15 Jan 2024, 11:08 | 782 | 782 µS/cm |
| 6 Dec 2023, 11:46 | 665 | 665 µS/cm |
| 20 Nov 2023, 10:56 | 764 | 764 µS/cm |
| 23 Oct 2023, 11:11 | 730 | 730 µS/cm |
Everything measured here
13 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 13 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 22 | Oct 2023 – Dec 2025 | 81.7% 16 Dec 2025 |
| Oxygen, Dissolved as O2 9924 | River water | 22 | Oct 2023 – Dec 2025 | 9.45 mg/l 16 Dec 2025 |
| Temperature of Water 0076 | River water | 22 | Oct 2023 – Dec 2025 | 8.9 °C 16 Dec 2025 |
| pH 0061 | River water | 22 | Oct 2023 – Dec 2025 | 7.55 16 Dec 2025 |
| Ammoniacal Nitrogen as N 0111 | River water | 21 | Oct 2023 – Dec 2025 | 0.13 mg/l 16 Dec 2025 |
| Nitrate as N 0117 | River water | 21 | Oct 2023 – Dec 2025 | 11 mg/l 16 Dec 2025 |
| Orthophosphate, reactive as P 0180 | River water | 21 | Oct 2023 – Dec 2025 | 0.15 mg/l 16 Dec 2025 |
| Conductivity at 25 C 0077 | River water | 22 | Oct 2023 – Dec 2025 | 578 µS/cm 16 Dec 2025 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 21 | Oct 2023 – Dec 2025 | 150 mg/l 16 Dec 2025 |
| Ammonia un-ionised as N 0119 | River water | 21 | Oct 2023 – Dec 2025 | 0.00078 mg/l 16 Dec 2025 |
| BOD : 5 Day ATU 0085 | River water | 17 | Feb 2024 – Dec 2025 | 1.8 mg/l 3 Dec 2025 |
| Nitrite as N 0118 | River water | 21 | Oct 2023 – Dec 2025 | 0.034 mg/l 16 Dec 2025 |
| Nitrogen, Total Oxidised as N 0116 | River water | 21 | Oct 2023 – Dec 2025 | 11 mg/l 16 Dec 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.