Sewage Map

Gellesfield CSO

Storm overflow operated by Northumbrian Water. The source names Black Burn as the receiving water.

52
Spills in 2025
177.9
Recorded hours
59%
Monitor operation
2
Years listed
Current status unknown

Checking the latest monitor report…

Open official annual data ↗

How it compares in 2025

Gellesfield CSO recorded 52 spills in 2025. That is more than 88% of the 14,239 overflows in England with a reported figure, and ranks 1,512th nationally. Among Northumbrian Water overflows it ranks 104th of 1,559; the median Northumbrian Water overflow recorded 11 spills. On the Team from Source to Tyne waterbody it ranks 3rd of 56.

The monitor worked for 59% of 2025, so this count may be low and its rank may understate activity.

GroupRank by spillsMedian spillsMedian hours
This outlet–52177.9
England1,512th of 14,2391122.3
Northumbrian Water104th of 1,5591115.6
Team from Source to Tyne3rd of 5683.9

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

752024522025
From 2024 to 2025, the reported count went from 75 to 52 spills. The highest count was 75 in 2024 and the lowest was 52 in 2025. The monitor worked for less than 90% of 2025, so that count may be low.Amber bars mark years when the monitor worked for less than 90% of the year.
YearSpillsDurationMonitor operationSource
202552177.9 hours59%Low coverageOfficial data
202475286.9 hours93.2%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
Northumbrian Water
Outlet type
Storm overflow on the sewer network
Permit
234/1059
Activity reference
A1
Grid reference
NZ2089659556
Waterbody ID
GB103023075670Official 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 0.6 km north of the Sunniside 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.

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Other outlet records nearby

Questions about Gellesfield CSO

Who operates Gellesfield CSO?
Northumbrian Water is the operator named in the annual record. The permit reference is 234/1059.
Where does Gellesfield CSO discharge?
The source names Black Burn as the receiving water. This does not show how far a discharge travelled.
How many times did Gellesfield CSO spill in 2025?
The 2025 return records 52 counted spill events and 177.9 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 59% of the reporting period. Below 90%, some events can be missed, so the count and hours may understate activity.
Is Gellesfield 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 Gellesfield 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 Gellesfield CSO compare with other overflows?
Gellesfield CSO recorded 52 spills in 2025. That is more than 88% of the 14,239 overflows in England with a reported figure, and ranks 1,512th nationally. Among Northumbrian Water overflows it ranks 104th of 1,559; the median Northumbrian Water overflow recorded 11 spills. On the Team from Source to Tyne waterbody it ranks 3rd of 56. 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.