Sewage Map

Wath On Dearne/STW

Storm overflow operated by Yorkshire Water. The source names Brook Dike/RIVER Dearne as the receiving water.

27
Spills in 2025
360.5
Recorded hours
100%
Monitor operation
6
Years listed

The reported spill count was 59 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

Wath On Dearne/STW recorded 27 spills in 2025. That is more than 71% of the 14,239 overflows in England with a reported figure, and ranks 3,910th nationally. Among Yorkshire Water overflows it ranks 748th of 2,176; the median Yorkshire Water overflow recorded 16 spills. On the River Dearne Darfield STW to River Don waterbody it ranks 3rd of 22.

GroupRank by spillsMedian spillsMedian hours
This outlet–27360.5
England3,910th of 14,2391122.3
Yorkshire Water748th of 2,1761637.8
River Dearne Darfield STW to River Don3rd of 221512.9

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

212020982021132022752023862024272025
From 2020 to 2025, the reported count went from 21 to 27 spills. The highest count was 98 in 2021 and the lowest was 13 in 2022.
YearSpillsDurationMonitor operationSource
202527360.5 hours100%Official data
2024861,194 hours100%Official data
2023751,106.8 hours99.6%Official data
202213151.3 hours99.7%Official data
2021981,053.3 hours98.2%Official data
202021127.2 hours100%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
Yorkshire Water
Outlet type
Storm tank at a wastewater treatment works
Permit
2172
Activity reference
3
Grid reference
SE4449001120
Waterbody ID
GB104027063173Official 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 “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 0.7 km north-east of the Wath upon Dearne 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 Wath On Dearne/STW

Who operates Wath On Dearne/STW?
Yorkshire Water is the operator named in the annual record. The permit reference is 2172.
Where does Wath On Dearne/STW discharge?
The source names Brook Dike/RIVER Dearne as the receiving water. This does not show how far a discharge travelled.
How many times did Wath On Dearne/STW spill in 2025?
The 2025 return records 27 counted spill events and 360.5 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 Wath On Dearne/STW 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 Wath On Dearne/STW?
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 Wath On Dearne/STW compare with other overflows?
Wath On Dearne/STW recorded 27 spills in 2025. That is more than 71% of the 14,239 overflows in England with a reported figure, and ranks 3,910th nationally. Among Yorkshire Water overflows it ranks 748th of 2,176; the median Yorkshire Water overflow recorded 16 spills. On the River Dearne Darfield STW to River Don waterbody it ranks 3rd of 22. 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.