Sewage Map

Stockwell Hill/CSO

Storm overflow operated by Yorkshire Water. The source names River Holme as the receiving water.

38
Spills in 2025
118.5
Recorded hours
100%
Monitor operation
4
Years listed

The reported spill count was 2 lower than in 2024. This compares event counts, not discharge volume.

Current status unknown

Checking the latest monitor report…

Open official annual data ↗

How it compares in 2025

Stockwell Hill/CSO recorded 38 spills in 2025. That is more than 81% of the 14,239 overflows in England with a reported figure, and ranks 2,593rd nationally. Among Yorkshire Water overflows it ranks 495th of 2,176; the median Yorkshire Water overflow recorded 16 spills. On the Holme from New Mill Dike to R Colne waterbody it ranks 5th of 15.

GroupRank by spillsMedian spillsMedian hours
This outlet–38118.5
England2,593rd of 14,2391122.3
Yorkshire Water495th of 2,1761637.8
Holme from New Mill Dike to R Colne5th of 151829.8

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

262022192023402024382025
From 2022 to 2025, the reported count went from 26 to 38 spills. The highest count was 40 in 2024 and the lowest was 19 in 2023. The monitor worked for less than 90% of 2022, so that count may be low.Amber bars mark years when the monitor worked for less than 90% of the year.
YearSpillsDurationMonitor operationSource
202538118.5 hours100%Official data
202440110 hours100%Official data
20231968 hours91.9%Official data
202226135.3 hours49.4%Low coverageOfficial 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
Yorkshire Water
Outlet type
Storm overflow on the sewer network
Permit
3659
Activity reference
A1
Grid reference
SE1360013700
Waterbody ID
GB104027063301Official 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 1 km north-east of the Netherton (Kirklees) 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

Questions about Stockwell Hill/CSO

Who operates Stockwell Hill/CSO?
Yorkshire Water is the operator named in the annual record. The permit reference is 3659.
Where does Stockwell Hill/CSO discharge?
The source names River Holme as the receiving water. This does not show how far a discharge travelled.
How many times did Stockwell Hill/CSO spill in 2025?
The 2025 return records 38 counted spill events and 118.5 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 Stockwell Hill/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 Stockwell Hill/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 Stockwell Hill/CSO compare with other overflows?
Stockwell Hill/CSO recorded 38 spills in 2025. That is more than 81% of the 14,239 overflows in England with a reported figure, and ranks 2,593rd nationally. Among Yorkshire Water overflows it ranks 495th of 2,176; the median Yorkshire Water overflow recorded 16 spills. On the Holme from New Mill Dike to R Colne waterbody it ranks 5th of 15. 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.