River Mersey above Northenden Weir
EA name: RIVER MERSEY ABOVE NORTHENDEN WEIR
Environment Agency sampling point NW-88002015 · 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
- 19 Mar 2025, 09:3118 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
- 20 since 20 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 383277, 390255As published, to the nearest 1 m. Open in a map
- River, by its own name
- Mersey
- River, by the map
- River MerseyPlaced on the river its name gives, 5 m from the line.
- Next gauge downstream
- Ashton Weir On the River Mersey · 11 km along the riverBeside Northenden: too close to say above or below.
- Nearest gauge upstream
- Didsbury River On the River Mersey · 3.5 km along the river
- Why it was sampled
- Monitoring (national agency policy) (18 samples)
Environmental monitoring statutory (EU directives) (2 samples)
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
92.7%
Sampled 19 Mar 2025, 18 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 19 Mar 2025, 09:31 | 92.7 | 92.7% |
| 19 Feb 2025, 08:33 | 98.3 | 98.3% |
| 28 Jan 2025, 08:36 | 102 | 102% |
| 5 Dec 2024, 08:25 | 95.6 | 95.6% |
| 20 Nov 2024, 09:32 | 94.9 | 94.9% |
| 17 Oct 2024, 08:52 | 98.8 | 98.8% |
| 16 Sep 2024, 15:05 | 97.1 | 97.1% |
| 21 Aug 2024, 12:35 | 96.4 | 96.4% |
| 19 Jul 2024, 10:08 | 96.3 | 96.3% |
| 20 Jun 2024, 13:57 | 101 | 101% |
| 31 May 2024, 11:11 | 97.7 | 97.7% |
| 27 Mar 2024, 11:10 | 98.5 | 98.5% |
| 22 Feb 2024, 09:54 | 101.8 | 101.8% |
| 17 Jan 2024, 07:38 | 98 | 98% |
| 5 Dec 2023, 12:02 | 101.4 | 101.4% |
| 20 Nov 2023, 12:09 | 102.8 | 102.8% |
| 20 Oct 2023, 07:40 | 95.5 | 95.5% |
Dissolved oxygen
as O2 · code 9924 · mg/l
11.4 mg/l
Sampled 19 Mar 2025, 18 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 19 Mar 2025, 09:31 | 11.4 | 11.4 mg/l |
| 19 Feb 2025, 08:33 | 12.8 | 12.8 mg/l |
| 28 Jan 2025, 08:36 | 12.7 | 12.7 mg/l |
| 5 Dec 2024, 08:25 | 11 | 11 mg/l |
| 20 Nov 2024, 09:32 | 11.9 | 11.9 mg/l |
| 17 Oct 2024, 08:52 | 10.4 | 10.4 mg/l |
| 16 Sep 2024, 15:05 | 9.83 | 9.83 mg/l |
| 21 Aug 2024, 12:35 | 9.53 | 9.53 mg/l |
| 19 Jul 2024, 10:08 | 9.13 | 9.13 mg/l |
| 20 Jun 2024, 13:57 | 9.96 | 9.96 mg/l |
| 31 May 2024, 11:11 | 10.2 | 10.2 mg/l |
| 27 Mar 2024, 11:10 | 11.3 | 11.3 mg/l |
| 22 Feb 2024, 09:54 | 12.1 | 12.1 mg/l |
| 17 Jan 2024, 07:38 | 12.8 | 12.8 mg/l |
| 5 Dec 2023, 12:02 | 12.5 | 12.5 mg/l |
| 20 Nov 2023, 12:09 | 11.7 | 11.7 mg/l |
| 20 Oct 2023, 07:40 | 10 | 10 mg/l |
Water temperature
code 0076 · °C
6.5 °C
Sampled 19 Mar 2025, 18 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 19 Mar 2025, 09:31 | 6.5 | 6.5 °C |
| 19 Feb 2025, 08:33 | 4.2 | 4.2 °C |
| 28 Jan 2025, 08:36 | 5.8 | 5.8 °C |
| 5 Dec 2024, 08:25 | 9.1 | 9.1 °C |
| 20 Nov 2024, 09:32 | 5.6 | 5.6 °C |
| 17 Oct 2024, 08:52 | 13.1 | 13.1 °C |
| 16 Sep 2024, 15:05 | 14.7 | 14.7 °C |
| 21 Aug 2024, 12:35 | 15.8 | 15.8 °C |
| 19 Jul 2024, 10:08 | 17.8 | 17.8 °C |
| 20 Jun 2024, 13:57 | 15.9 | 15.9 °C |
| 31 May 2024, 11:11 | 13.4 | 13.4 °C |
| 27 Mar 2024, 11:10 | 9.2 | 9.2 °C |
| 22 Feb 2024, 09:54 | 7.9 | 7.9 °C |
| 17 Jan 2024, 07:38 | 4.2 | 4.2 °C |
| 5 Dec 2023, 12:02 | 6.3 | 6.3 °C |
| 20 Nov 2023, 12:09 | 9.7 | 9.7 °C |
| 20 Oct 2023, 07:40 | 13 | 13 °C |
pH
code 0061
7.83
Sampled 19 Mar 2025, 18 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 19 Mar 2025, 09:31 | 7.83 | 7.83 |
| 19 Feb 2025, 08:33 | 7.67 | 7.67 |
| 28 Jan 2025, 08:36 | 7.87 | 7.87 |
| 5 Dec 2024, 08:25 | 7.67 | 7.67 |
| 20 Nov 2024, 09:32 | 7.65 | 7.65 |
| 17 Oct 2024, 08:52 | 7.62 | 7.62 |
| 16 Sep 2024, 15:05 | 7.5 | 7.5 |
| 21 Aug 2024, 12:35 | 7.76 | 7.76 |
| 19 Jul 2024, 10:08 | 7.6 | 7.6 |
| 20 Jun 2024, 13:57 | 7.71 | 7.71 |
| 31 May 2024, 11:11 | 7.65 | 7.65 |
| 27 Mar 2024, 11:10 | 7.79 | 7.79 |
| 22 Feb 2024, 09:54 | 7.75 | 7.75 |
| 17 Jan 2024, 07:38 | 7.77 | 7.77 |
| 5 Dec 2023, 12:02 | 7.57 | 7.57 |
| 20 Nov 2023, 12:09 | 7.59 | 7.59 |
| 20 Oct 2023, 07:40 | 7.37 | 7.37 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
0.16 mg/l
Sampled 19 Mar 2025, 18 months ago · 16 results banked
Every result (16)
| Sampled | Result as published | Reads as |
|---|---|---|
| 19 Mar 2025, 09:31 | 0.16 | 0.16 mg/l |
| 19 Feb 2025, 08:33 | 0.36 | 0.36 mg/l |
| 28 Jan 2025, 08:36 | 0.15 | 0.15 mg/l |
| 5 Dec 2024, 08:25 | 0.28 | 0.28 mg/l |
| 20 Nov 2024, 09:32 | 0.15 | 0.15 mg/l |
| 17 Oct 2024, 08:52 | 0.21 | 0.21 mg/l |
| 21 Aug 2024, 12:35 | 0.081 | 0.081 mg/l |
| 19 Jul 2024, 10:08 | 0.097 | 0.097 mg/l |
| 20 Jun 2024, 13:57 | 0.14 | 0.14 mg/l |
| 31 May 2024, 11:11 | 0.088 | 0.088 mg/l |
| 27 Mar 2024, 11:10 | 0.18 | 0.18 mg/l |
| 22 Feb 2024, 09:54 | 0.29 | 0.29 mg/l |
| 17 Jan 2024, 07:38 | 0.32 | 0.32 mg/l |
| 5 Dec 2023, 12:02 | 0.22 | 0.22 mg/l |
| 20 Nov 2023, 12:09 | 0.04 | 0.04 mg/l |
| 20 Oct 2023, 07:40 | 0.084 | 0.084 mg/l |
Nitrate
as nitrogen (N) · code 0117 · mg/l
6.55 mg/l
Sampled 19 Mar 2025, 18 months ago · 15 results banked
Every result (15)
| Sampled | Result as published | Reads as |
|---|---|---|
| 19 Mar 2025, 09:31 | 6.55 | 6.55 mg/l |
| 19 Feb 2025, 08:33 | 4.84 | 4.84 mg/l |
| 28 Jan 2025, 08:36 | 2.14 | 2.14 mg/l |
| 20 Nov 2024, 09:32 | 4.44 | 4.44 mg/l |
| 17 Oct 2024, 08:52 | 2.15 | 2.15 mg/l |
| 21 Aug 2024, 12:35 | 6.97 | 6.97 mg/l |
| 19 Jul 2024, 10:08 | 4.36 | 4.36 mg/l |
| 20 Jun 2024, 13:57 | 5.14 | 5.14 mg/l |
| 31 May 2024, 11:11 | 3.15 | 3.15 mg/l |
| 27 Mar 2024, 11:10 | 3.14 | 3.14 mg/l |
| 22 Feb 2024, 09:54 | 1.48 | 1.48 mg/l |
| 17 Jan 2024, 07:38 | 4.04 | 4.04 mg/l |
| 5 Dec 2023, 12:02 | 2.42 | 2.42 mg/l |
| 20 Nov 2023, 12:09 | 1.39 | 1.39 mg/l |
| 20 Oct 2023, 07:40 | 2.95 | 2.95 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.18 mg/l
Sampled 19 Mar 2025, 18 months ago · 16 results banked
Every result (16)
| Sampled | Result as published | Reads as |
|---|---|---|
| 19 Mar 2025, 09:31 | 0.18 | 0.18 mg/l |
| 19 Feb 2025, 08:33 | 0.16 | 0.16 mg/l |
| 28 Jan 2025, 08:36 | 0.082 | 0.082 mg/l |
| 5 Dec 2024, 08:25 | 0.18 | 0.18 mg/l |
| 20 Nov 2024, 09:32 | 0.24 | 0.24 mg/l |
| 17 Oct 2024, 08:52 | 0.17 | 0.17 mg/l |
| 21 Aug 2024, 12:35 | 0.56 | 0.56 mg/l |
| 19 Jul 2024, 10:08 | 0.25 | 0.25 mg/l |
| 20 Jun 2024, 13:57 | 0.33 | 0.33 mg/l |
| 31 May 2024, 11:11 | 0.16 | 0.16 mg/l |
| 27 Mar 2024, 11:10 | 0.16 | 0.16 mg/l |
| 22 Feb 2024, 09:54 | 0.086 | 0.086 mg/l |
| 17 Jan 2024, 07:38 | 0.2 | 0.2 mg/l |
| 5 Dec 2023, 12:02 | 0.16 | 0.16 mg/l |
| 20 Nov 2023, 12:09 | 0.06 | 0.06 mg/l |
| 20 Oct 2023, 07:40 | 0.23 | 0.23 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
386 µS/cm
Sampled 19 Mar 2025, 18 months ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 19 Mar 2025, 09:31 | 386 | 386 µS/cm |
| 19 Feb 2025, 08:33 | 356 | 356 µS/cm |
| 28 Jan 2025, 08:36 | 229 | 229 µS/cm |
| 5 Dec 2024, 08:25 | 311 | 311 µS/cm |
| 20 Nov 2024, 09:32 | 436 | 436 µS/cm |
| 17 Oct 2024, 08:52 | 202 | 202 µS/cm |
| 16 Sep 2024, 15:05 | 295 | 295 µS/cm |
| 21 Aug 2024, 12:35 | 385 | 385 µS/cm |
| 19 Jul 2024, 10:08 | 319 | 319 µS/cm |
| 20 Jun 2024, 13:57 | 339 | 339 µS/cm |
| 31 May 2024, 11:11 | 257 | 257 µS/cm |
| 27 Mar 2024, 11:10 | 271 | 271 µS/cm |
| 22 Feb 2024, 09:54 | 184 | 184 µS/cm |
| 17 Jan 2024, 07:38 | 402 | 402 µS/cm |
| 5 Dec 2023, 12:02 | 304 | 304 µS/cm |
| 20 Nov 2023, 12:09 | 162 | 162 µS/cm |
| 20 Oct 2023, 07:40 | 228 | 228 µS/cm |
Everything measured here
19 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 19 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 17 | Oct 2023 – Mar 2025 | 92.7% 19 Mar 2025 |
| Oxygen, Dissolved as O2 9924 | River water | 17 | Oct 2023 – Mar 2025 | 11.4 mg/l 19 Mar 2025 |
| Temperature of Water 0076 | River water | 17 | Oct 2023 – Mar 2025 | 6.5 °C 19 Mar 2025 |
| pH 0061 | River water | 17 | Oct 2023 – Mar 2025 | 7.83 19 Mar 2025 |
| Ammoniacal Nitrogen as N 0111 | River water | 16 | Oct 2023 – Mar 2025 | 0.16 mg/l 19 Mar 2025 |
| Nitrate as N 0117 | River water | 15 | Oct 2023 – Mar 2025 | 6.55 mg/l 19 Mar 2025 |
| Orthophosphate, reactive as P 0180 | River water | 16 | Oct 2023 – Mar 2025 | 0.18 mg/l 19 Mar 2025 |
| Conductivity at 25 C 0077 | River water | 17 | Oct 2023 – Mar 2025 | 386 µS/cm 19 Mar 2025 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 16 | Oct 2023 – Mar 2025 | 78 mg/l 19 Mar 2025 |
| Ammonia un-ionised as N 0119 | River water | 16 | Oct 2023 – Mar 2025 | 0.00153 mg/l 19 Mar 2025 |
| BOD : 5 Day ATU 0085 | River water | 11 | Apr 2024 – Mar 2025 | 3 mg/l 19 Mar 2025 |
| Cadmium, Dissolved 0106 | River water | 2 | Oct 2023 – Feb 2024 | 0.038 µg/l 22 Feb 2024 |
| Calcium, Dissolved 0239 | River water | 2 | Oct 2023 – Feb 2024 | 21 mg/l 22 Feb 2024 |
| Carbon, Organic, Dissolved as C :- {DOC} 0301 | River water | 2 | Oct 2023 – Feb 2024 | 6.9 mg/l 22 Feb 2024 |
| Magnesium, Dissolved 0235 | River water | 2 | Oct 2023 – Feb 2024 | 3 mg/l 22 Feb 2024 |
| Mercury, Dissolved 0103 | River water | 2 | Oct 2023 – Feb 2024 | 0.043 µg/l 22 Feb 2024 |
| Nitrite as N 0118 | River water | 16 | Oct 2023 – Mar 2025 | 0.054 mg/l 19 Mar 2025 |
| Nitrogen, Total Oxidised as N 0116 | River water | 15 | Oct 2023 – Mar 2025 | 6.6 mg/l 19 Mar 2025 |
| Pentachlorophenol 1085 | River water | 2 | Oct 2023 – Feb 2024 | below 0.02 µg/l 22 Feb 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.