Sewage Map

Great Hatfield/No 2 STW

Storm overflow operated by Yorkshire Water. The source names Unnamed Tributary of Catchwater Drn as the receiving water.

43
Spills in 2025
493.8
Recorded hours
100%
Monitor operation
3
Years listed

The reported spill count was 7 lower than in 2024. This compares event counts, not discharge volume.

Current status unknown

Checking the latest monitor report…

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How it compares in 2025

Great Hatfield/No 2 STW recorded 43 spills in 2025. That is more than 84% of the 14,239 overflows in England with a reported figure, and ranks 2,156th nationally. Among Yorkshire Water overflows it ranks 406th of 2,176; the median Yorkshire Water overflow recorded 16 spills. On the Lambwath Stream from Source to Foredyke Stream waterbody it ranks 1st of 3.

GroupRank by spillsMedian spillsMedian hours
This outlet–43493.8
England2,156th of 14,2391122.3
Yorkshire Water406th of 2,1761637.8
Lambwath Stream from Source to Foredyke Stream1st of 341296.8

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

292023502024432025
From 2023 to 2025, the reported count went from 29 to 43 spills. The highest count was 50 in 2024 and the lowest was 29 in 2023.
YearSpillsDurationMonitor operationSource
202543493.8 hours100%Official data
202450584 hours100%Official data
202329141.5 hours99.8%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
Inlet storm overflow at a wastewater treatment works
Permit
WRA8394
Activity reference
A2
Grid reference
TA1821042730
Waterbody ID
GB104026066860Official 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 “Inlet SO at WwTW”: inlet storm overflow at a wastewater treatment works. The overflow is at the inlet of a treatment works, where wastewater enters the 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 2.7 km north-west of the Withernwick 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 Great Hatfield/No 2 STW

Who operates Great Hatfield/No 2 STW?
Yorkshire Water is the operator named in the annual record. The permit reference is WRA8394.
Where does Great Hatfield/No 2 STW discharge?
The source names Unnamed Tributary of Catchwater Drn as the receiving water. This does not show how far a discharge travelled.
How many times did Great Hatfield/No 2 STW spill in 2025?
The 2025 return records 43 counted spill events and 493.8 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 Great Hatfield/No 2 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 Great Hatfield/No 2 STW?
The annual return lists the asset type as “Inlet SO at WwTW”, which means inlet storm overflow at a wastewater treatment works. The overflow is at the inlet of a treatment works, where wastewater enters the works.
How does Great Hatfield/No 2 STW compare with other overflows?
Great Hatfield/No 2 STW recorded 43 spills in 2025. That is more than 84% of the 14,239 overflows in England with a reported figure, and ranks 2,156th nationally. Among Yorkshire Water overflows it ranks 406th of 2,176; the median Yorkshire Water overflow recorded 16 spills. On the Lambwath Stream from Source to Foredyke Stream waterbody it ranks 1st of 3. 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.