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River Cober water levels

Live levels from 4 monitoring stations across Cornwall, updated every 15 minutes.

4stations
0above typical high

Gauges

Monitoring stations, source to mouth

StationTownLevel nowStatusTrend
TrenearWendron0.36 m 43m agoNormal—
BoscadjackWendron0.28 m 43m agoNormal—
Helston County BridgeHelston0.18 m 43m agoLow—
Loe PoolHelston3.55 m 43m agoNormal—

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 Cober above one of its gauges, from the source down. The river map knows where gauges are, not every stream, so a tributary without a gauge is not listed here.

No gauged tributary joins the Cober above Loe Pool on the river map. Streams without a gauge are not counted here.

Where the Cober goes

Below Loe Pool, its water next reaches LOE BAR, 1.9 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.

Storm overflows upstream

5 storm overflows are traced upstream of Loe Pool, the Cober’s lowest gauge on the river map: on the Cober itself, on its gauged tributaries, and on smaller streams that join above there.

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

Official figures for 2025, for the overflows traced upstream of Loe Pool: 98 spills over 409 hours in total, across all 5.

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 Cober includes the smaller streams that join it there.

Between Helston County Bridge and Loe Pool5 overflows
  • Helston Market Pumping Station Not discharging
    South West Water · into River Cober · 2.0 km by river above Loe Pool · 2025: 3 spills, 1.3 h
  • Coinagehall Street CSO Not discharging
    South West Water · into River Cober Via Sws · 1.9 km by river above Loe Pool · 2025: 61 spills, 67 h · reaches the river through a sewer, so where it enters is approximate
  • Grange Road CSO Not discharging
    South West Water · into River Cober (Via Sws) · 1.9 km by river above Loe Pool · 2025: 2 spills, 0.2 h · reaches the river through a sewer, so where it enters is approximate
  • Monument Road CSO Not discharging
    South West Water · into River Cober Via Sws · 1.9 km by river above Loe Pool · 2025: 0 spills, 0 h · reaches the river through a sewer, so where it enters is approximate
  • Helston WwTW Not discharging
    South West Water · into River Cober · 1.4 km by river above Loe Pool · 2025: 32 spills, 340 h

Near these gauges, connection not known

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

  • Breageside Pumping Station (Porthle Not discharging bathing water
    South West Water · into Mounts Bay, English Channel · 1.8 km from Loe Pool in a straight line · discharges to the sea, an estuary or tidal water · 2025: 0 spills, 0 h
  • Porthleven Harbour Attenuation Not discharging bathing water
    South West Water · into Mounts Bay · 1.9 km from Loe Pool in a straight line · discharges to the sea, an estuary or tidal water · 2025: 13 spills, 54 h

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: © South West Water 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.

24 sampling points on the River Cober and the streams that join it above Loe Pool. 16 have a sample from the last 12 months; 16 have any sample banked. Listed from the source down, grouped by the next gauge each one's water reaches.

Above Trenear River Cober 11 points, 7 with samples
Sampling pointWatercourse (map)Above the gaugeLast sampleLatest results (river water)
Cober Waterbody Background Site 2River Cober5.6 kmLast sampled 13 Jan 2011, before the imported period
River Cober at Burras BridgeRiver Cober5.5 km15 Dec 2025 · 10 months agoOxygen 99.2%Temp 10.6 °CpH 6.39Ammonia 0.23 mg/l
Halwin Stream at confluence with Medlyn Streamunnamed stream4.4 km22 Sep 2026 · 16 days agoOxygen 92.9%Temp 16.9 °CpH 7.1Conductivity 128 µS/cm
Medlyn Stream at Gweal-An-Deeblesunnamed stream4.1 km22 Sep 2026 · 16 days agoOxygen 94.3%Temp 16.6 °CpH 7.2Conductivity 130 µS/cm
River Cober at PorkellisRiver Cober3.6 km22 Sep 2026 · 16 days agoOxygen 95.7%Temp 15.2 °CpH 6.61Conductivity 156 µS/cm
Medlyn Stream at Chy Bridgeunnamed stream2.7 km22 Sep 2026 · 16 days agoOxygen 92.6%Temp 16.2 °CpH 7Conductivity 130 µS/cm
Tributary of Bodilly Stream downstream of Releath Farmunnamed stream2.4 kmLast sampled 16 Mar 2016, before the imported period
Bodilly Stream at Bodilly Millunnamed stream1.2 kmLast sampled 10 Sep 2013, before the imported period
River Cober at Trenear BridgeRiver Cober0.7 km22 Sep 2026 · 16 days agoOxygen 94.4%Temp 15.6 °CpH 7Conductivity 140 µS/cm
Bodilly Stream upstream of Cober confluenceRiver Cober0.2 kmLast sampled 16 Mar 2016, before the imported period
River Cober at WendronRiver Cober0.2 km20 Jul 2026 · 3 months agoOxygen 100.2%Temp 18.3 °CpH 7.47Ammonia 4 mg/l
Above Helston County Bridge River Cober 6 points, 5 with samples
Sampling pointWatercourse (map)Above the gaugeLast sampleLatest results (river water)
Mellangoose Stream at Trevarno Estateunnamed stream4.2 km7 Jul 2026 · 3 months agoOxygen 97.3%Temp 14.4 °CpH 6.9Conductivity 238 µS/cm
River Cober at Coverack BridgeRiver Cober3.8 kmLast sampled 16 Mar 2016, before the imported period
Mellangoose Stream upstream of Truthall Wood tributaryunnamed stream2.9 km7 Jul 2026 · 3 months agoOxygen 96.9%Temp 16.5 °CpH 7.2Conductivity 239 µS/cm
River Cober at Lowertown BridgeRiver Cober2.1 km15 Sep 2026 · 23 days agoOxygen 102% Jul 2026Oxygen 10.7 mg/l May 2026Temp 16.4 °CpH 7.1 Jul 2026
Mellangoose Stream Prior to Coberunnamed stream1.9 km7 Jul 2026 · 3 months agoOxygen 98.8%Temp 16.1 °CpH 7.1Conductivity 236 µS/cm
River Cober at St Johns BridgeRiver Cober0.3 km29 Sep 2026 · 9 days agoOxygen 98.1%Temp 15.8 °CpH 7.32Ammonia below 0.03 mg/l
Above Loe Pool River Cober 7 points, 4 with samples
Sampling pointWatercourse (map)Above the gaugeLast sampleLatest results (river water)
River Cober at Helston Park G StationRiver Cober1.8 km7 Jul 2026 · 3 months agoOxygen 96.5% Jul 2024Temp 15.9 °CpH 7.1Ammonia 0.032 mg/l
River Cober upstream of Helston sewage treatment worksRiver Cober1.5 km29 Sep 2026 · 9 days agoOxygen 97.2%Temp 15.9 °CpH 7.37Ammonia below 0.03 mg/l
River Cober upstream of sewage treatment works Discharge, downstream of PondRiver Cober1.4 kmLast sampled 26 Nov 2015, before the imported period
River Cober downstream of Helston sewage treatment worksRiver Cober1.3 kmLast sampled 13 Mar 2020, before the imported period
Tributary of Cober from Penventon FarmRiver Cober1.3 kmLast sampled 16 Mar 2016, before the imported period
River Cober 200 m downstream of Helston sewage treatment worksRiver Cober1.2 km7 Jul 2026 · 3 months agopH 7.15
River Cober at Inflow to Loe PoolRiver Cober0.7 km10 Aug 2026 · 59 days agoOxygen 93.6%Temp 17.8 °CpH 7.54Ammonia 0.037 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.