Coinagehall St CSO Helston
Storm overflow operated by South West Water. The source names River Cober via SWS as the receiving water.
- 61
- Spills in 2025
- 66.7
- Recorded hours
- 81.5%
- Monitor operation
- 5
- Years listed
Checking the latest monitor report…
How it compares in 2025
Coinagehall St CSO Helston recorded 61 spills in 2025. That is more than 92% of the 14,239 overflows in England with a reported figure, and ranks 1,061st nationally. Among South West Water overflows it ranks 267th of 1,357; the median South West Water overflow recorded 21 spills. On the Lower River Cober waterbody it ranks 1st of 5.
The monitor worked for 81.5% of 2025, so this count may be low and its rank may understate activity.
| Group | Rank by spills | Median spills | Median hours |
|---|---|---|---|
| This outlet | – | 61 | 66.7 |
| England | 1,061st of 14,239 | 11 | 22.3 |
| South West Water | 267th of 1,357 | 21 | 39.4 |
| Lower River Cober | 1st of 5 | 3 | 1.3 |
Rank 1 has the most spills. Equal counts share a rank. Only overflows with a reported count are ranked. Counts do not measure volume, so a higher rank does not mean more sewage.
Annual spill history
| Year | Spills | Duration | Monitor operation | Source |
|---|---|---|---|---|
| 2025 | 61 | 66.7 hours | 81.5%Low coverage | Official data |
| 2024 | 79 | 103 hours | 100% | Official data |
| 2023 | 82 | 115 hours | 100% | Official data |
| 2022 | 68 | 65.3 hours | 82%Low coverage | Official data |
| 2021 | 77 | 87.1 hours | 100% | Official data |
A missing figure means the source did not provide a usable value. A zero is shown as zero. Monitor operation below 90% can make comparison less reliable.
Outlet details
- Water company
- South West Water
- Outlet type
- Storm overflow on the sewer network
- Permit
- 034260/CS/01
- Activity reference
- A1
- Grid reference
- SW65532731
- Waterbody ID
- GB108048001172Official waterbody record ↗
- Location source
- Official annual grid reference
- Location precision
- About 10 metres
- Location note
- Unknown
About the name and type
The annual return lists this asset as “SO on sewer network”: storm overflow on the sewer network. The return places this overflow on the sewer network.
The waterbody link opens the Environment Agency record for the exact ID in the return. It is a source lookup; we do not import its classification.
Where it is
The recorded position is about 0.8 km west of the Helston reference point in the ONS built-up areas data.
Area and water pages
Check the official record
Public access to this outlet is unknown. Do not enter restricted land or use this page as a route guide.
Open official source ↗Other outlet records nearby
- Grange Rd S.A. Tank CSO HelstonCurrent status unknown
South West Water · River Cober (via SWS)
- The Monument CSO HelstonCurrent status unknown
South West Water · River Cober via SWS
- Helston Market Spst Pscsoeo HelstonCurrent status unknown
South West Water · River Cober
- Helston STW SSO HelstonCurrent status unknown
South West Water · River Cober
Questions about Coinagehall St CSO Helston
- Who operates Coinagehall St CSO Helston?
- South West Water is the operator named in the annual record. The permit reference is 034260/CS/01.
- Where does Coinagehall St CSO Helston discharge?
- The source names River Cober via SWS as the receiving water. This does not show how far a discharge travelled.
- How many times did Coinagehall St CSO Helston spill in 2025?
- The 2025 return records 61 counted spill events and 66.7 hours of recorded discharge. Spills are counted with the 12/24-hour method, so this is not a count of every start signal.
- Can I trust the 2025 figures for this outlet?
- The monitor worked for 81.5% of the reporting period. Below 90%, some events can be missed, so the count and hours may understate activity.
- Is Coinagehall St CSO Helston discharging right now?
- This record is linked to a company live feed. The panel above shows the latest report we hold, with its date. That report can be old, and the monitor can be offline, so check the date before relying on it. A report that no discharge is taking place is not a water-quality result.
- How accurate is the map marker?
- The marker comes from the grid reference in the official annual return, which is accurate to about 10 metres. It shows the recorded outlet position, not the extent of any discharge.
- What kind of outlet is Coinagehall St CSO Helston?
- The annual return lists the asset type as “SO on sewer network”, which means storm overflow on the sewer network. The return places this overflow on the sewer network.
- How does Coinagehall St CSO Helston compare with other overflows?
- Coinagehall St CSO Helston recorded 61 spills in 2025. That is more than 92% of the 14,239 overflows in England with a reported figure, and ranks 1,061st nationally. Among South West Water overflows it ranks 267th of 1,357; the median South West Water overflow recorded 21 spills. On the Lower River Cober waterbody it ranks 1st of 5. Ranks compare counted spill events only. They do not compare volume or harm.
- Does zero spills mean the water was safe?
- No. A zero means the annual return recorded zero counted spill events for this outlet and year. It is not a water-quality test, and pollution can come from other sources.