Swan Mill CSO
Storm overflow operated by United Utilities. The source names Springs Brook as the receiving water.
- 54
- Spills in 2025
- 86.3
- Recorded hours
- 87.6%
- Monitor operation
- 2
- Years listed
Checking the latest monitor report…
How it compares in 2025
Swan Mill CSO recorded 54 spills in 2025. That is more than 89% of the 14,239 overflows in England with a reported figure, and ranks 1,394th nationally. Among United Utilities overflows it ranks 379th of 2,270; the median United Utilities overflow recorded 15 spills. On the Wince Brook waterbody it ranks 1st of 17.
The monitor worked for 87.6% of 2025, so this count may be low and its rank may understate activity.
| Group | Rank by spills | Median spills | Median hours |
|---|---|---|---|
| This outlet | – | 54 | 86.3 |
| England | 1,394th of 14,239 | 11 | 22.3 |
| United Utilities | 379th of 2,270 | 15 | 29.1 |
| Wince Brook | 1st of 17 | 14 | 34.5 |
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 | 54 | 86.3 hours | 87.6%Low coverage | Official data |
| 2024 | 77 | 168.2 hours | 98.3% | 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
- United Utilities
- Outlet type
- Storm overflow on the sewer network
- Permit
- 016983314
- Activity reference
- A1
- Grid reference
- SD8896004570
- Waterbody ID
- GB112069061120Official waterbody record ↗
- Location source
- Official annual grid reference
- Location precision
- About 1 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 0.9 km north-west of the Chadderton reference point in the ONS built-up areas data.
Area and water pages
- Manchester area →
- Droylsden area →
- Audenshaw area →
- Chadderton area →
- Whitefield area →
- Pendlebury area →
- Salford area →
- Prestwich area →
- Failsworth area →
- Rhodes area →
- Simister area →
- Woodhouses area →
- Middleton (Rochdale) area →
- Ashton-under-Lyne area →
- Birch area →
- Dukinfield area →
- Oldham area →
- Slattocks area →
- Heywood area →
- Royton area →
- Trub area →
- Mossley area →
- Wince Brook waterbody →
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
- The Causeway (Chadderton) Wastewater Network Pumping StationCurrent status unknown
United Utilities · Wince Brook
- South Chadderton / The Causeway Oldham CSOCurrent status unknown
United Utilities · Wince Brook
- Moston Road Combined Sewer Overflow/Chadderton Low Level Pumping Station (318N4) (OLD0157)Current status unknown
United Utilities · Wince Brook
- OLDHAM WwTWCurrent status unknown
United Utilities · Wince Brook
Questions about Swan Mill CSO
- Who operates Swan Mill CSO?
- United Utilities is the operator named in the annual record. The permit reference is 016983314.
- Where does Swan Mill CSO discharge?
- The source names Springs Brook as the receiving water. This does not show how far a discharge travelled.
- How many times did Swan Mill CSO spill in 2025?
- The 2025 return records 54 counted spill events and 86.3 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 87.6% of the reporting period. Below 90%, some events can be missed, so the count and hours may understate activity.
- Is Swan Mill CSO 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 1 metres. It shows the recorded outlet position, not the extent of any discharge.
- What kind of outlet is Swan Mill CSO?
- 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 Swan Mill CSO compare with other overflows?
- Swan Mill CSO recorded 54 spills in 2025. That is more than 89% of the 14,239 overflows in England with a reported figure, and ranks 1,394th nationally. Among United Utilities overflows it ranks 379th of 2,270; the median United Utilities overflow recorded 15 spills. On the Wince Brook waterbody it ranks 1st of 17. 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.