Altarnun STW SSO Altarnun
Storm overflow operated by South West Water. The source names Penpont Water as the receiving water.
- 165
- Spills in 2025
- 3,294.5
- Recorded hours
- 100%
- Monitor operation
- 5
- Years listed
The reported spill count was 41 lower than in 2024. This compares event counts, not discharge volume.
Checking the latest monitor report…
How it compares in 2025
Altarnun STW SSO Altarnun recorded 165 spills in 2025. That is more than 99% of the 14,239 overflows in England with a reported figure, and ranks 23rd nationally. Among South West Water overflows it ranks 14th of 1,357; the median South West Water overflow recorded 21 spills. On the Penpont Water waterbody it ranks 1st of 4.
| Group | Rank by spills | Median spills | Median hours |
|---|---|---|---|
| This outlet | – | 165 | 3,294.5 |
| England | 23rd of 14,239 | 11 | 22.3 |
| South West Water | 14th of 1,357 | 21 | 39.4 |
| Penpont Water | 1st of 4 | 13.5 | 217.2 |
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 | 165 | 3,294.5 hours | 100% | Official data |
| 2024 | 206 | 3,917.7 hours | 100% | Official data |
| 2023 | 145 | 2,898.5 hours | 98.4% | Official data |
| 2022 | 160 | 2,352.8 hours | 100% | Official data |
| 2021 | 155 | 2,169.6 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 tank at a wastewater treatment works
- Permit
- SWWA 154
- Activity reference
- A3
- Grid reference
- SX22408140
- Waterbody ID
- GB108047007700Official 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 “Storm tank at WwTW”: storm tank at a wastewater treatment works. The overflow comes from storm storage at a treatment works.
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 5.2 km west of the Lewannick 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
- War Memorial SPS Pscsoeo AltarnunCurrent status unknown
South West Water · Peneont Water (S)
- Polyphant Spst Pscsoeo PolyphantCurrent status unknown
South West Water · River Inny (S)
- Lewannick STW So LewannickCurrent status unknown
South West Water · Penpont(S)
- Egloskerry STW So EgloskerryCurrent status unknown
South West Water · River Kensey (S)
Questions about Altarnun STW SSO Altarnun
- Who operates Altarnun STW SSO Altarnun?
- South West Water is the operator named in the annual record. The permit reference is SWWA 154.
- Where does Altarnun STW SSO Altarnun discharge?
- The source names Penpont Water as the receiving water. This does not show how far a discharge travelled.
- How many times did Altarnun STW SSO Altarnun spill in 2025?
- The 2025 return records 165 counted spill events and 3,294.5 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 100% of the reporting period, so the annual figures cover most of the year. They still do not measure discharge volume.
- Is Altarnun STW SSO Altarnun 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 Altarnun STW SSO Altarnun?
- The annual return lists the asset type as “Storm tank at WwTW”, which means storm tank at a wastewater treatment works. The overflow comes from storm storage at a treatment works.
- How does Altarnun STW SSO Altarnun compare with other overflows?
- Altarnun STW SSO Altarnun recorded 165 spills in 2025. That is more than 99% of the 14,239 overflows in England with a reported figure, and ranks 23rd nationally. Among South West Water overflows it ranks 14th of 1,357; the median South West Water overflow recorded 21 spills. On the Penpont Water waterbody it ranks 1st of 4. 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.