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River Darwen water levels

Live levels from 5 monitoring stations across Blackburn with Darwen, Lancashire, updated every 15 minutes.

5stations
0above typical high

Gauges

Monitoring stations, source to mouth

StationTownLevel nowStatusTrend
Darwen Clough Street OverflowDarwen0.51 m 33m agoNormal—
Hardman WayDarwen0.05 m 33m agoNormal—
EwoodLower Darwen0.29 m 33m agoLow—
Blackburn WaterfallBlackburn0.40 m 33m agoLow—
Blue BridgeWalton-Le-Dale0.24 m 33m agoLow—

Stations are listed from source to mouth as the water flows, traced on the river map (OS Open Rivers) and the Environment Agency’s own links between its gauges. A distance “by river” is along the river, and is shown only where the map traces the path.

Contains OS data © Crown copyright and database rights 2026.

Gauged tributaries

Streams and rivers with a gauge whose water joins the Darwen above one of its gauges, from the source down. Named streams without a gauge that have a page here are listed at the end.

2 gauged tributaries, 4 gauges

Where the Darwen goes

Below Blue Bridge, its water next reaches Penwortham, a gauge on River Ribble, 4.5 km by river downstream.

Tributaries and where they join are traced on the river map (OS Open Rivers, edition 2026-04) and the Environment Agency’s links between its gauges. The map holds distances between gauges, not the junctions themselves, so a junction is placed between two gauges, and no further up than the tributary’s own lowest gauge. Contains OS data © Crown copyright and database rights 2026.

Streams without a gauge

Named streams on the river map that flow into the Darwen and have no gauge of their own. Each has a page with what is known about it: the next gauge downstream, and any storm overflows or water-sampling points placed on it.

Storm overflows upstream

48 storm overflows are traced upstream of Blue Bridge, the Darwen’s lowest gauge on the river map: on the Darwen itself, on its gauged tributaries, and on smaller streams that join above there.

  • 0 report discharging now
  • 46 not discharging
  • 2 offline or silent: 0 monitor offline, 0 status unknown, 2 no live feed

Official figures for 2025, for the overflows traced upstream of Blue Bridge: 883 spills over 2,345 hours in total, across all 48.

Each overflow is listed in the stretch above the first gauge its water reaches, from the source down, as on the Gauges tab. A stretch of the Darwen includes the smaller streams that join it there. Every overflow traced is listed here, each stretch in full. Back to the short lists →

Between Darwen Clough Street Overflow and Hardman Way10 overflows
  • Cranberry Lane CSO Not discharging
    United Utilities · into Trib River Darwen · 1.6 km by river above Hardman Way · 2025: 2 spills, 6.0 h
  • Bolton Road CSO Not discharging
    United Utilities · into Tributary Of River Darwen · 1.5 km by river above Hardman Way · 2025: 0 spills, 0 h
  • Grimshaw Street CSO Not discharging
    United Utilities · into River Darwen · 1.3 km by river above Hardman Way · 2025: 20 spills, 26 h
  • Footpath Nr Cross St CSO Not discharging
    United Utilities · into River Darwen · 1.2 km by river above Hardman Way · 2025: 3 spills, 0.3 h
  • Bolton Road CSO Not discharging
    United Utilities · into Unnamed Trib Of River Darwen · 770 m by river above Hardman Way · 2025: 5 spills, 1.4 h
  • Bolton Road/Astley Street CSO Not discharging
    United Utilities · into Kebbs Brook,trib Of Riv Darwen · 770 m by river above Hardman Way · 2025: 9 spills, 3.5 h
  • Coal Pit Lane CSO No live feed
    United Utilities · into Kebbs Brook,trib Of Riv Darwen · 770 m by river above Hardman Way · 2025: 15 spills, 43 h
  • Belgrave Road CSO Not discharging
    United Utilities · into Tributary Of River Darwen · 710 m by river above Hardman Way · 2025: 0 spills, 0 h
  • Balle Street Hilton Street CSO Not discharging
    United Utilities · into River Darwen · 540 m by river above Hardman Way · 2025: 46 spills, 28 h
  • Balle Street Hilton Street CSO Not discharging
    United Utilities · into River Darwen · 540 m by river above Hardman Way · 2025: 56 spills, 62 h
Between Hardman Way and Ewood9 overflows
  • Waterside CSO 052z1 Not discharging
    United Utilities · into Waterside Brook · 7.2 km by river above Ewood · 2025: 9 spills, 37 h
  • Redearth Road/Sudell Road CSO Not discharging
    United Utilities · into River Darwen · 5.7 km by river above Ewood · 2025: 3 spills, 0.8 h
  • Church Street/Parliament Street CSO Not discharging
    United Utilities · into Culverted Section River Darwen · 5.6 km by river above Ewood · 2025: 7 spills, 1.7 h
  • Railway Road/South Street CSO Not discharging
    United Utilities · into Clvrtd Section Of River Darwen · 5.4 km by river above Ewood · 2025: 0 spills, 0 h
  • 28 Tythebarn St Not discharging
    United Utilities · into River Darwen (Sewer) · 5.3 km by river above Ewood · 2025: 20 spills, 16 h · reaches the river through a sewer, so where it enters is approximate
  • Hindle Street CSO Not discharging
    United Utilities · into River Darwen Via Sws · 4.9 km by river above Ewood · 2025: 14 spills, 14 h · reaches the river through a sewer, so where it enters is approximate
  • Woodvale Flats CSO Not discharging
    United Utilities · into River Darwen · 4.9 km by river above Ewood · 2025: 0 spills, 0 h
  • Clarence Street CSO Not discharging
    United Utilities · into River Darwen · 3.8 km by river above Ewood · 2025: 42 spills, 69 h
  • Lower Eccleshill Road CSO Not discharging
    United Utilities · into River Darwen · 3.0 km by river above Ewood · 2025: 39 spills, 266 h
Between Ewood and Blackburn Waterfall2 overflows
  • Bolton Road Combined Sewer Overflow Not discharging
    United Utilities · into Unnamed Trib Of River Darwen · 620 m by river above Blackburn Waterfall · 2025: 45 spills, 46 h
  • Aqueduct Road CSO Not discharging
    United Utilities · into River Darwen · 510 m by river above Blackburn Waterfall · 2025: 53 spills, 335 h
Between Blackburn Waterfall and Blue Bridge13 overflows
  • Fielden Street CSO Not discharging
    United Utilities · into River Blakewater · 19.4 km by river above Blue Bridge · 2025: 3 spills, 3.1 h
  • Addison Close CSO Not discharging
    United Utilities · into River Blakewater · 19.4 km by river above Blue Bridge · 2025: 49 spills, 71 h
  • Apple Street CSO Not discharging
    United Utilities · into River Blakewater · 18.9 km by river above Blue Bridge · 2025: 5 spills, 1.1 h
  • Wellington Road CSO Not discharging
    United Utilities · into River Darwen · 18.8 km by river above Blue Bridge · 2025: 2 spills, 0.5 h
  • Manor Road CSO (052er) Not discharging
    United Utilities · into River Blakewater · 18.6 km by river above Blue Bridge · 2025: 3 spills, 0.3 h
  • Witton Tanks CSO Not discharging
    United Utilities · into River Blakewater · 18.3 km by river above Blue Bridge · 2025: 41 spills, 81 h
  • 293 Preston Old Road CSO (052m0) Not discharging
    United Utilities · into River Darwen · 17.6 km by river above Blue Bridge · 2025: 0 spills, 0 h
  • 293 Preston Old Road CSO (052m0) Not discharging
    United Utilities · into River Blakewater · 17.5 km by river above Blue Bridge · 2025: 0 spills, 0 h
  • Abbey Village Pumping Station Not discharging
    United Utilities · into River Roddlesworth · 17.1 km by river above Blue Bridge · 2025: 41 spills, 342 h
  • Preston New Road Not discharging
    United Utilities · into Trib Of Arley Brook · 13.9 km by river above Blue Bridge · 2025: 36 spills, 59 h
  • Blackburn WwTW No live feed bathing water shellfish water
    United Utilities · into Hole Brook & River Darwen · 6.1 km by river above Blue Bridge · 2025: 19 spills, 28 h
  • Daub Hall Lane CSO 403cw Not discharging
    United Utilities · into Black Brook · 3.5 km by river above Blue Bridge · 2025: 67 spills, 166 h
  • Cann Bridge Street CSO 40042 Not discharging
    United Utilities · into River Darwen · 1.4 km by river above Blue Bridge · 2025: 16 spills, 9.7 h
River Blakewater, above Gorse Streetjoins the Darwen above Blue Bridge1 overflow
  • Accrington Road CSO Not discharging
    United Utilities · into Clvrt'd Section Knuzden Brook · 1.9 km by river above Gorse Street · 2025: 43 spills, 90 h
River Blakewater, above Harrison Streetjoins the Darwen above Blue Bridge13 overflows
  • Whalley Old Rd/Providence St CSO Not discharging
    United Utilities · into Little Harwood Brook · 3.2 km by river above Harrison Street · 2025: 58 spills, 204 h
  • Philips Road CSO Not discharging
    United Utilities · into River Blakewater · 2.8 km by river above Harrison Street · 2025: 32 spills, 187 h
  • Beechwood Road CSO Not discharging
    United Utilities · into River Blakewater · 2.8 km by river above Harrison Street · 2025: 3 spills, 0.6 h
  • Notre Dame Gardens CSO Not discharging
    United Utilities · into River Blakewater · 2.4 km by river above Harrison Street · 2025: 1 spill, 0.6 h
  • Whalley New Road CSO Not discharging
    United Utilities · into River Blakewater · 2.2 km by river above Harrison Street · 2025: 2 spills, 0.1 h
  • Whalley Range / Wesley Street CSO Not discharging
    United Utilities · into River Blakewater · 2.2 km by river above Harrison Street · 2025: 0 spills, 0 h
  • Whalley Range/Grace Street CSO Not discharging
    United Utilities · into River Blakewater · 2.0 km by river above Harrison Street · 2025: 3 spills, 0.3 h
  • New Mill Street CSO Not discharging
    United Utilities · into River Blakewater · 1.9 km by river above Harrison Street · 2025: 4 spills, 15 h
  • Whalley Range/Millham Street CSO Not discharging
    United Utilities · into River Blakewater Via Sws · 1.8 km by river above Harrison Street · 2025: 3 spills, 0.3 h · reaches the river through a sewer, so where it enters is approximate
  • Lark Hill/Brookhouse Lane CSO Not discharging
    United Utilities · into Tributary Of River Blakewater · 1.8 km by river above Harrison Street · 2025: 3 spills, 0.2 h
  • Victoria Street CSO Not discharging
    United Utilities · into River Blakewater · 1.3 km by river above Harrison Street · 2025: 11 spills, 2.6 h
  • Thwaites Brewery Yard Not discharging
    United Utilities · into River Blakewater · 1.3 km by river above Harrison Street · 2025: 50 spills, 127 h
  • Great Bolton Street CSO Not discharging
    United Utilities · into River Blakewater · 350 m by river above Harrison Street · 2025: 0 spills, 0 h

Near these gauges, connection not known

Within 3 km of one of the Darwen’s gauges in a straight line, but the river map cannot say whether their water reaches it.

  • Kay Street CSO Not discharging
    United Utilities · into Trib River Darwen · 340 m from Hardman Way in a straight line · no mapped watercourse close enough to be sure · 2025: 0 spills, 0 h
  • Sudell Road CSO Not discharging
    United Utilities · into Trib River Darwen · 510 m from Hardman Way in a straight line · no mapped watercourse close enough to be sure · 2025: 26 spills, 25 h
  • Sudellside Street Not discharging
    United Utilities · into Trib River Darwen · 510 m from Hardman Way in a straight line · no mapped watercourse close enough to be sure · 2025: 0 spills, 0 h
  • Infirmary Street CSO 05050 Not discharging
    United Utilities · into Leeds/Liverpool Canal · 570 m from Blackburn Waterfall in a straight line · its recorded watercourse is not the one mapped beside it · 2025: 0 spills, 0 h
  • Queens Road (Darwen) CSO Not discharging
    United Utilities · into Tributary Of River Darwen · 580 m from Darwen Clough Street Overflow in a straight line · no mapped watercourse close enough to be sure · 2025: 0 spills, 0 h
  • Field East Of River Darwin CSO Not discharging bathing water shellfish water
    United Utilities · into River Darwin · 620 m from Blue Bridge in a straight line · its recorded watercourse is not the one mapped beside it · 2025: 56 spills, 474 h
  • Vale Street Not discharging
    United Utilities · into Trib River Darwen · 640 m from Hardman Way in a straight line · no mapped watercourse close enough to be sure · 2025: 1 spill, 0.1 h
  • Higher Perry St/Black Laurel St CSO Not discharging
    United Utilities · into Tributary Of River Darwen · 700 m from Hardman Way in a straight line · no mapped watercourse close enough to be sure · 2025: 68 spills, 62 h
  • Sharples Street CSO Not discharging
    United Utilities · into Tributary Of River Darwen · 700 m from Blackburn Waterfall in a straight line · no mapped watercourse close enough to be sure · 2025: 145 spills, 381 h
  • Cotton Hall Street CSO Not discharging
    United Utilities · into Tributary Of River Darwen · 750 m from Hardman Way in a straight line · no mapped watercourse close enough to be sure · 2025: 43 spills, 27 h
  • Anyon Street/Laurel Ave CSO Not discharging
    United Utilities · into Tributary Of River Darwen · 850 m from Hardman Way in a straight line · its watercourse is not on the river map · 2025: 63 spills, 107 h
  • Grimshaw Park CSO Not discharging
    United Utilities · into River Blakewater · 1.2 km from Ewood in a straight line · no mapped watercourse close enough to be sure · 2025: 0 spills, 0 h
  • Hennel Lane CSO Not discharging
    United Utilities · into River Darwen · 1.3 km from Blue Bridge in a straight line · discharges into a tidal reach, where the water moves both ways · 2025: 43 spills, 318 h
  • Lower Audley CSO Not discharging
    United Utilities · into Tributary Of River Blakewater · 1.3 km from Blackburn Waterfall in a straight line · no mapped watercourse close enough to be sure · 2025: 40 spills, 98 h
  • Brownedge Lane CSO 401gr Not discharging
    United Utilities · into Cockshott Bk Trb R Darwen · 1.5 km from Blue Bridge in a straight line · its watercourse is not on the river map · 2025: 2 spills, 6.7 h

29 more near these gauges whose connection is not known.

2 other overflows within 3 km of these gauges are placed below the Darwen’s lowest gauge or on another river, so not listed.

A status is the water company’s own monitor: it says whether an overflow is discharging, never how much or why, and a spill does not by itself explain a change in a river level. A status older than two hours is shown as unknown. Annual figures are the official returns: 12/24-hour spills for England and Wales, overflow events for Scotland (Scottish Water counts differently, so the two cannot be compared). “No data” means the monitor produced no usable data that year, not zero. Overflows are placed on OS Open Rivers (edition 2026-04), which leaves out many small channels: an overflow the map cannot place may still drain here. Contains OS data © Crown copyright and database rights 2026. Sewage in Britain’s rivers →

Live status: © United Utilities storm overflow activity data, licensed under CC BY 4.0. Annual figures for England: Environment Agency Event Duration Monitoring return, © Environment Agency copyright and/or database right, Open Government Licence v3.0.

Water samples

Dated samples taken by the Environment Agency, not live readings. Results are published days to months after the sample is taken, and many points are sampled only a few times a year, or have not been sampled for years.

26 sampling points on the River Darwen and the streams that join it above Blue Bridge. 4 have a sample from the last 12 months; 9 have any sample banked. Listed from the source down, grouped by the next gauge each one's water reaches.

Above Darwen Clough Street Overflow River Darwen 3 points, 1 with samples
Sampling pointWatercourse (map)Above the gaugeLast sampleLatest results (river water)
Drain upstream of Jack Keys Reservoir SD7035220094unnamed stream1.0 kmLast sampled 17 May 2013, before the imported period
River Darwen downstream of Jack Keys ReservoirRiver Darwen0.4 kmLast sampled 17 May 2013, before the imported period
River Darwen below Jack Keys ReservoirRiver Darwen0.2 km11 May 2026 · 5 months agoOxygen 98.9%Temp 9.5 °CpH 8.15Ammonia 0.062 mg/l
Above Gorse Street River Blakewater 1 point
Sampling pointWatercourse (map)Above the gaugeLast sampleLatest results (river water)
Knuzden Brook above the confluence with River BlakewaterKnuzden Brook0.5 km10 Mar 2025 · 19 months agoOxygen 100.8%Temp 6.5 °CpH 7.92Ammonia 0.095 mg/l
Above Harrison Street River Blakewater 2 points, 0 with samples
Sampling pointWatercourse (map)Above the gaugeLast sampleLatest results (river water)
River Blakewater at Gorse St BridgeRiver Blakewater3.4 kmLast sampled 6 Dec 2017, before the imported period
River Blakewater at Whalley New Road BridgeRiver Blakewater2.3 kmLast sampled 6 Dec 2017, before the imported period
Above Ewood River Darwen 6 points, 1 with samples
Sampling pointWatercourse (map)Above the gaugeLast sampleLatest results (river water)
Waterside Brook downstream of Reservoir confluenceWaterside Brook6.4 kmLast sampled 12 Mar 2015, before the imported period
Sunnyhurst Brook downstream of Earnsdale ReservoirSunnyhurst Brook5.0 kmLast sampled 12 Mar 2015, before the imported period
River Darwen below Hollins Paper MillRiver Darwen3.2 kmLast sampled 24 Apr 2018, before the imported period
Waterside Brook above the confluence with River DarwenDavy Field Brook2.6 km10 Mar 2025 · 19 months agoOxygen 103%Temp 6.6 °CpH 8.18Ammonia 0.055 mg/l
River Darwen above the confluence with Waterside BrookRiver Darwen2.5 kmLast sampled 31 Mar 2005, before the imported period
River Darwen downstream of Waterside BrookRiver Darwen1.8 kmLast sampled 5 Mar 2015, before the imported period
Above Blue Bridge River Darwen 14 points, 6 with samples
Sampling pointWatercourse (map)Above the gaugeLast sampleLatest results (river water)
River Blakewater at Lancaster Street Road BridgeRiver Blakewater19 kmLast sampled 6 Dec 2017, before the imported period
River Darwen at Feniscliffe BridgeRiver Darwen18 km24 Jun 2026 · 3 months agoOxygen 113.8%Temp 18.2 °CpH 8.52Ammonia below 0.03 mg/l
River Blakewater above the confluence with River DarwenRiver Blakewater18 km24 Jun 2026 · 3 months agoOxygen 91.5%Temp 18.8 °CpH 8.05Ammonia 0.11 mg/l
River Roddlesworth at SD 646 227River Roddlesworth18 kmLast sampled 10 Mar 2020, before the imported period
River Darwen at Plessington FieldsRiver Darwen17 kmLast sampled 14 Jan 2020, before the imported period
River Darwen upstream of Butler's BridgeRiver Darwen16 km10 Dec 2024 · 22 months agoOxygen 98.9%Temp 6.4 °CpH 8.14Ammonia 0.041 mg/l Nov 2024
Finnington Brook above the confluence with River RoddlesworthFinnington Brook14 kmLast sampled 7 Jun 2007, before the imported period
River Roddlesworth above the confluence with River DarwenRiver Roddlesworth14 km12 Mar 2025 · 19 months agoOxygen 103.3%Temp 5.8 °CpH 8.3Ammonia 0.037 mg/l
River Darwen at Hoghton BottomsRiver Darwen11 kmLast sampled 3 Mar 2020, before the imported period
River Darwen at Samlesbury Mill BridgeRiver Darwen8.2 kmLast sampled 9 Mar 2005, before the imported period
Hole Brook above the confluence with River DarwenHole Brook6.1 kmLast sampled 23 May 2018, before the imported period
River Darwen at Roach BridgeRiver Darwen4.8 km7 Sep 2026 · 31 days agoOxygen 101% Mar 2025Temp 8 °C Mar 2025pH 8.35Ammonia 0.035 mg/l Mar 2025
Fowler Brook above the confluence with River DarwenFowler Brook2.8 kmLast sampled 3 Mar 2020, before the imported period
Many Brooks above the confluence with River DarwenMany Brooks1.5 km10 Mar 2025 · 19 months agoOxygen 110.8%Temp 7.4 °CpH 8.41Ammonia 0.077 mg/l

Distances are along the river to the gauge named. England's samples only.

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.