River Darwen at Roach Bridge
EA name: RIVER DARWEN AT ROACH BRIDGE
Environment Agency sampling point NW-88003559 · 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
- 7 Sep 2026, 11:4231 days ago · time as the Environment Agency records it (UK clock time; the source gives no time zone)
- Samples banked
- 17 since 1 Dec 2023 Imported periods: 1 Oct 2023 – 8 Oct 2026. Samples outside them are not shown here.
- Latest sample
- River / running surface water Monitoring (national agency policy) · results completed 18 Sep 2026
- Where
- National Grid 359574, 428820As published, to the nearest 1 m. Open in a map
- River, by its own name
- Darwen
- River, by the map
- River DarwenPlaced on the river its name gives, 27 m from the line.
- Next gauge downstream
- Blue Bridge On the River Darwen · 4.8 km along the river
- Nearest gauge upstream
- Blackburn Waterfall On the River Darwen · 14 km along the riverHarrison Street On the River Blakewater · 15 km along the river
- Why it was sampled
- Environmental monitoring statutory (EU directives) (13 samples)
Monitoring (national agency policy) (4 samples)
Results here were completed a median of 11 days after the sample was taken (11 to 11 days, 1 samples).
Main measurements, river water
Dissolved oxygen
% saturation · code 9901 · %
101%
Sampled 3 Mar 2025, 19 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 3 Mar 2025, 09:51 | 101 | 101% |
| 4 Feb 2025, 11:53 | 102 | 102% |
| 15 Jan 2025, 09:37 | 101.9 | 101.9% |
| 2 Dec 2024, 10:08 | 103.7 | 103.7% |
| 5 Nov 2024, 10:16 | 102.8 | 102.8% |
| 3 Oct 2024, 12:36 | 101.5 | 101.5% |
| 6 Sep 2024, 12:32 | 84.2 | 84.2% |
| 1 Aug 2024, 15:34 | 102.1 | 102.1% |
| 10 Jul 2024, 09:20 | 100.9 | 100.9% |
| 4 Jun 2024, 12:33 | 101.1 | 101.1% |
| 1 May 2024, 12:36 | 103.5 | 103.5% |
| 4 Apr 2024, 09:28 | 102.8 | 102.8% |
Dissolved oxygen
as O2 · code 9924 · mg/l
11.9 mg/l
Sampled 3 Mar 2025, 19 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 3 Mar 2025, 09:51 | 11.9 | 11.9 mg/l |
| 4 Feb 2025, 11:53 | 12 | 12 mg/l |
| 15 Jan 2025, 09:37 | 12.3 | 12.3 mg/l |
| 2 Dec 2024, 10:08 | 11.6 | 11.6 mg/l |
| 5 Nov 2024, 10:16 | 11.1 | 11.1 mg/l |
| 3 Oct 2024, 12:36 | 10.8 | 10.8 mg/l |
| 6 Sep 2024, 12:32 | 8.12 | 8.12 mg/l |
| 1 Aug 2024, 15:34 | 9.35 | 9.35 mg/l |
| 10 Jul 2024, 09:20 | 10 | 10 mg/l |
| 4 Jun 2024, 12:33 | 10.2 | 10.2 mg/l |
| 1 May 2024, 12:36 | 10.6 | 10.6 mg/l |
| 4 Apr 2024, 09:28 | 11.8 | 11.8 mg/l |
Water temperature
code 0076 · °C
8 °C
Sampled 3 Mar 2025, 19 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 3 Mar 2025, 09:51 | 8 | 8 °C |
| 4 Feb 2025, 11:53 | 8.3 | 8.3 °C |
| 15 Jan 2025, 09:37 | 7.2 | 7.2 °C |
| 2 Dec 2024, 10:08 | 10.2 | 10.2 °C |
| 5 Nov 2024, 10:16 | 11.8 | 11.8 °C |
| 3 Oct 2024, 12:36 | 12.6 | 12.6 °C |
| 6 Sep 2024, 12:32 | 17 | 17 °C |
| 1 Aug 2024, 15:34 | 19.5 | 19.5 °C |
| 10 Jul 2024, 09:20 | 15.6 | 15.6 °C |
| 4 Jun 2024, 12:33 | 15 | 15 °C |
| 1 May 2024, 12:36 | 14 | 14 °C |
| 4 Apr 2024, 09:28 | 9.2 | 9.2 °C |
pH
code 0061
8.35
Sampled 7 Sep 2026, 31 days ago · 17 results banked
Every result (17)
| Sampled | Result as published | Reads as |
|---|---|---|
| 7 Sep 2026, 11:42 | 8.35 | 8.35 |
| 4 Jun 2026, 11:26 | 8.01 | 8.01 |
| 26 Mar 2026, 11:42 | 7.95 | 7.95 |
| 16 Dec 2025, 10:35 | 7.75 | 7.75 |
| 3 Mar 2025, 09:51 | 8.18 | 8.18 |
| 4 Feb 2025, 11:53 | 8.1 | 8.1 |
| 15 Jan 2025, 09:37 | 7.94 | 7.94 |
| 2 Dec 2024, 10:08 | 8.17 | 8.17 |
| 5 Nov 2024, 10:16 | 8.15 | 8.15 |
| 3 Oct 2024, 12:36 | 8.19 | 8.19 |
| 6 Sep 2024, 12:32 | 8.32 | 8.32 |
| 1 Aug 2024, 15:34 | 8.22 | 8.22 |
| 10 Jul 2024, 09:20 | 8.43 | 8.43 |
| 4 Jun 2024, 12:33 | 8.46 | 8.46 |
| 1 May 2024, 12:36 | 8.41 | 8.41 |
| 4 Apr 2024, 09:28 | 8.02 | 8.02 |
| 1 Dec 2023, 11:17 | 7.57 | 7.57 |
Ammonia
ammoniacal nitrogen as N · code 0111 · mg/l
0.035 mg/l
Sampled 3 Mar 2025, 19 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 3 Mar 2025, 09:51 | 0.035 | 0.035 mg/l |
| 4 Feb 2025, 11:53 | 0.053 | 0.053 mg/l |
| 15 Jan 2025, 09:37 | 0.12 | 0.12 mg/l |
| 2 Dec 2024, 10:08 | 0.12 | 0.12 mg/l |
| 5 Nov 2024, 10:16 | 0.038 | 0.038 mg/l |
| 3 Oct 2024, 12:36 | <0.03 | below 0.03 mg/l (not detected above this) |
| 6 Sep 2024, 12:32 | 0.051 | 0.051 mg/l |
| 1 Aug 2024, 15:34 | 0.09 | 0.09 mg/l |
| 10 Jul 2024, 09:20 | 0.1 | 0.1 mg/l |
| 4 Jun 2024, 12:33 | 0.037 | 0.037 mg/l |
| 1 May 2024, 12:36 | <0.03 | below 0.03 mg/l (not detected above this) |
| 4 Apr 2024, 09:28 | 0.089 | 0.089 mg/l |
Nitrate
as nitrogen (N) · code 0117 · mg/l
1.95 mg/l
Sampled 3 Mar 2025, 19 months ago · 11 results banked
Every result (11)
| Sampled | Result as published | Reads as |
|---|---|---|
| 3 Mar 2025, 09:51 | 1.95 | 1.95 mg/l |
| 4 Feb 2025, 11:53 | 3.37 | 3.37 mg/l |
| 15 Jan 2025, 09:37 | 0.97 | 0.97 mg/l |
| 5 Nov 2024, 10:16 | 2.35 | 2.35 mg/l |
| 3 Oct 2024, 12:36 | 0.656 | 0.656 mg/l |
| 6 Sep 2024, 12:32 | 0.735 | 0.735 mg/l |
| 1 Aug 2024, 15:34 | 0.543 | 0.543 mg/l |
| 10 Jul 2024, 09:20 | 1.46 | 1.46 mg/l |
| 4 Jun 2024, 12:33 | 1.67 | 1.67 mg/l |
| 1 May 2024, 12:36 | 1.88 | 1.88 mg/l |
| 4 Apr 2024, 09:28 | 1.66 | 1.66 mg/l |
Phosphate
orthophosphate, reactive, as P · code 0180 · mg/l
0.033 mg/l
Sampled 3 Mar 2025, 19 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 3 Mar 2025, 09:51 | 0.033 | 0.033 mg/l |
| 4 Feb 2025, 11:53 | 0.042 | 0.042 mg/l |
| 15 Jan 2025, 09:37 | 0.046 | 0.046 mg/l |
| 2 Dec 2024, 10:08 | 0.11 | 0.11 mg/l |
| 5 Nov 2024, 10:16 | 0.061 | 0.061 mg/l |
| 3 Oct 2024, 12:36 | 0.078 | 0.078 mg/l |
| 6 Sep 2024, 12:32 | 0.13 | 0.13 mg/l |
| 1 Aug 2024, 15:34 | 0.15 | 0.15 mg/l |
| 10 Jul 2024, 09:20 | 0.11 | 0.11 mg/l |
| 4 Jun 2024, 12:33 | 0.048 | 0.048 mg/l |
| 1 May 2024, 12:36 | 0.03 | 0.03 mg/l |
| 4 Apr 2024, 09:28 | 0.064 | 0.064 mg/l |
Conductivity
at 25 °C · code 0077 · µS/cm
505 µS/cm
Sampled 3 Mar 2025, 19 months ago · 12 results banked
Every result (12)
| Sampled | Result as published | Reads as |
|---|---|---|
| 3 Mar 2025, 09:51 | 505 | 505 µS/cm |
| 4 Feb 2025, 11:53 | 457 | 457 µS/cm |
| 15 Jan 2025, 09:37 | 444 | 444 µS/cm |
| 2 Dec 2024, 10:08 | 423 | 423 µS/cm |
| 5 Nov 2024, 10:16 | 462 | 462 µS/cm |
| 3 Oct 2024, 12:36 | 420 | 420 µS/cm |
| 6 Sep 2024, 12:32 | 443 | 443 µS/cm |
| 1 Aug 2024, 15:34 | 473 | 473 µS/cm |
| 10 Jul 2024, 09:20 | 344 | 344 µS/cm |
| 4 Jun 2024, 12:33 | 504 | 504 µS/cm |
| 1 May 2024, 12:36 | 249 | 249 µS/cm |
| 4 Apr 2024, 09:28 | 342 | 342 µS/cm |
Everything measured here
69 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 69 rows
| Determinand | Material | Results | First – last | Latest result |
|---|---|---|---|---|
| Oxygen, Dissolved, % Saturation 9901 | River water | 12 | Apr 2024 – Mar 2025 | 101% 3 Mar 2025 |
| Oxygen, Dissolved as O2 9924 | River water | 12 | Apr 2024 – Mar 2025 | 11.9 mg/l 3 Mar 2025 |
| Temperature of Water 0076 | River water | 12 | Apr 2024 – Mar 2025 | 8 °C 3 Mar 2025 |
| pH 0061 | River water | 17 | Dec 2023 – Sep 2026 | 8.35 7 Sep 2026 |
| Ammoniacal Nitrogen as N 0111 | River water | 12 | Apr 2024 – Mar 2025 | 0.035 mg/l 3 Mar 2025 |
| Nitrate as N 0117 | River water | 11 | Apr 2024 – Mar 2025 | 1.95 mg/l 3 Mar 2025 |
| Orthophosphate, reactive as P 0180 | River water | 12 | Apr 2024 – Mar 2025 | 0.033 mg/l 3 Mar 2025 |
| Conductivity at 25 C 0077 | River water | 12 | Apr 2024 – Mar 2025 | 505 µS/cm 3 Mar 2025 |
| 11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (F-53B Minor) 2993 | River water | 1 | May 2024 – May 2024 | below 0.001 µg/l 1 May 2024 |
| 2-(N-Ethylperfluorooctanesulfonamido)acetic acid (B) 2942 | River water | 1 | May 2024 – May 2024 | below 0.001 µg/l 1 May 2024 |
| 2-(N-Ethylperfluorooctanesulfonamido)acetic acid (L) 2991 | River water | 1 | May 2024 – May 2024 | below 0.001 µg/l 1 May 2024 |
| 2-(N-Methylperfluorooctanesulfonamido)acetic acid (B) 2943 | River water | 1 | May 2024 – May 2024 | below 0.002 µg/l 1 May 2024 |
| 2-(N-Methylperfluorooctanesulfonamido)acetic acid (L) 2990 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| 2H,2H,3H,3H-Perfluorooctanoic acid 2989 | River water | 1 | May 2024 – May 2024 | below 0.001 µg/l 1 May 2024 |
| 3-Perfluoroheptylpropanoic acid 2925 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| 3:3 Fluorotelomer carboxylic acid 2926 | River water | 1 | May 2024 – May 2024 | below 0.004 µg/l 1 May 2024 |
| 4,8-Dioxa-3H-perfluorononanoic acid (ADONA) 2988 | River water | 1 | May 2024 – May 2024 | below 0.005 µg/l 1 May 2024 |
| 4:2 Fluorotelomer sulfonic acid 2987 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| 6:2 Fluorotelomer sulfonic acid 2984 | River water | 1 | May 2024 – May 2024 | 0.0061 µg/l 1 May 2024 |
| 8:2 Fluorotelomer sulfonic acid 2983 | River water | 1 | May 2024 – May 2024 | below 0.001 µg/l 1 May 2024 |
| 9-chlorohexadecafluoro-3-oxanonane-1-sulfonic acid 2982 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Alkalinity to pH 4.5 as CaCO3 0162 | River water | 12 | Apr 2024 – Mar 2025 | 140 mg/l 3 Mar 2025 |
| Ammonia un-ionised as N 0119 | River water | 12 | Apr 2024 – Mar 2025 | 0.00055 mg/l 3 Mar 2025 |
| Cadmium, Dissolved 0106 | River water | 8 | Dec 2023 – Sep 2026 | below 0.01 µg/l 7 Sep 2026 |
| Calcium, Dissolved 0239 | River water | 8 | Dec 2023 – Sep 2026 | 46 mg/l 7 Sep 2026 |
| Carbon, Organic, Dissolved as C :- {DOC} 0301 | River water | 8 | Dec 2023 – Sep 2026 | 5.8 mg/l 7 Sep 2026 |
| HCH -alpha 0487 | River water | 1 | Dec 2023 – Dec 2023 | below 0.0001 µg/l 1 Dec 2023 |
| HCH -beta 0491 | River water | 1 | Dec 2023 – Dec 2023 | below 0.0001 µg/l 1 Dec 2023 |
| HCH -delta 0495 | River water | 1 | Dec 2023 – Dec 2023 | below 0.0001 µg/l 1 Dec 2023 |
| HCH -gamma :- {Lindane} 0499 | River water | 1 | Dec 2023 – Dec 2023 | 0.0002 µg/l 1 Dec 2023 |
| Hexafluoropropylene oxide dimer acid (Gen X) 2981 | River water | 1 | May 2024 – May 2024 | below 0.001 µg/l 1 May 2024 |
| Magnesium, Dissolved 0235 | River water | 8 | Dec 2023 – Sep 2026 | 6.1 mg/l 7 Sep 2026 |
| Mercury, Dissolved 0103 | River water | 1 | Dec 2023 – Dec 2023 | below 0.01 µg/l 1 Dec 2023 |
| N-Ethylperfluorooctanesulfonamide 2977 | River water | 1 | May 2024 – May 2024 | below 0.002 µg/l 1 May 2024 |
| N-methylperfluorooctanesulfonamide 2975 | River water | 1 | May 2024 – May 2024 | below 0.002 µg/l 1 May 2024 |
| Nitrite as N 0118 | River water | 11 | Apr 2024 – Mar 2025 | 0.049 mg/l 3 Mar 2025 |
| Nitrogen, Total Oxidised as N 0116 | River water | 12 | Apr 2024 – Mar 2025 | 2 mg/l 3 Mar 2025 |
| Pentachlorophenol 1085 | River water | 1 | Dec 2023 – Dec 2023 | below 0.02 µg/l 1 Dec 2023 |
| Perfluoro(2-ethoxyethane)sulfonic acid 2924 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Perfluoro(4-methoxybutanoic) acid 2923 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Perfluoro-3,6-dioxaheptanoic acid 2922 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Perfluoro-3-methoxypropanoic acid 2921 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Perfluoro-4-ethylcyclohexanesulfonic acid 2973 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Perfluorobutanesulfonic acid 2972 | River water | 1 | May 2024 – May 2024 | 0.0023 µg/l 1 May 2024 |
| Perfluorobutanoic acid 2995 | River water | 1 | May 2024 – May 2024 | 0.0039 µg/l 1 May 2024 |
| Perfluorobutylsulfonamide (perfluorobutane sulfonamide) 2970 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Perfluorodecanesulfonic acid 2969 | River water | 1 | May 2024 – May 2024 | below 0.002 µg/l 1 May 2024 |
| Perfluorodecanoic acid 8892 | River water | 1 | May 2024 – May 2024 | below 0.002 µg/l 1 May 2024 |
| Perfluorododecane sulfonic acid 2968 | River water | 1 | May 2024 – May 2024 | below 0.005 µg/l 1 May 2024 |
| Perfluorododecanoic acid 8894 | River water | 1 | May 2024 – May 2024 | below 0.002 µg/l 1 May 2024 |
| Perfluoroheptanesulfonic acid 2967 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Perfluoroheptanoic acid 8889 | River water | 1 | May 2024 – May 2024 | 0.0017 µg/l 1 May 2024 |
| Perfluorohexanesulfonamide 2965 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Perfluorohexanesulfonic acid (B) 2944 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Perfluorohexanesulfonic acid (L) 2964 | River water | 1 | May 2024 – May 2024 | 0.00058 µg/l 1 May 2024 |
| Perfluorohexanoic acid 8888 | River water | 1 | May 2024 – May 2024 | 0.0045 µg/l 1 May 2024 |
| Perfluorononanesulfonic acid 2963 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Perfluorononanoic acid 8891 | River water | 1 | May 2024 – May 2024 | below 0.001 µg/l 1 May 2024 |
| Perfluorooctadecanoic acid 2962 | River water | 1 | May 2024 – May 2024 | below 0.002 µg/l 1 May 2024 |
| Perfluorooctanesulfonamide 2961 | River water | 1 | May 2024 – May 2024 | below 0.001 µg/l 1 May 2024 |
| Perfluorooctanesulfonic acid (branched) 2960 | River water | 1 | May 2024 – May 2024 | 0.0012 µg/l 1 May 2024 |
| Perfluorooctanesulfonic acid (linear) 2959 | River water | 1 | May 2024 – May 2024 | 0.0012 µg/l 1 May 2024 |
| Perfluorooctanoic acid 8890 | River water | 1 | May 2024 – May 2024 | 0.0086 µg/l 1 May 2024 |
| Perfluoropentanesulfonic acid 2957 | River water | 1 | May 2024 – May 2024 | below 0.0005 µg/l 1 May 2024 |
| Perfluoropentanoic acid 8887 | River water | 1 | May 2024 – May 2024 | 0.0033 µg/l 1 May 2024 |
| Perfluorotetradecanoic acid 8895 | River water | 1 | May 2024 – May 2024 | below 0.006 µg/l 1 May 2024 |
| Perfluorotridecanoic acid 2955 | River water | 1 | May 2024 – May 2024 | below 0.005 µg/l 1 May 2024 |
| Perfluoroundecane sulfonic acid 2953 | River water | 1 | May 2024 – May 2024 | below 0.004 µg/l 1 May 2024 |
| Perfluoroundecanoic acid 8893 | River water | 1 | May 2024 – May 2024 | below 0.002 µg/l 1 May 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.