Sewage Map

Crawley STW

Storm overflow operated by Thames Water. The source names Tributary of Gatwick Stream as the receiving water.

33
Spills in 2025
362.6
Recorded hours
88%
Monitor operation
3
Years listed
Current status unknown

Checking the latest monitor report…

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How it compares in 2025

Crawley STW recorded 33 spills in 2025. That is more than 77% of the 14,239 overflows in England with a reported figure, and ranks 3,116th nationally. Among Thames Water overflows it ranks 92nd of 579; the median Thames Water overflow recorded 6 spills.

The monitor worked for 88% of 2025, so this count may be low and its rank may understate activity.

GroupRank by spillsMedian spillsMedian hours
This outlet–33362.6
England3,116th of 14,2391122.3
Thames Water92nd of 579620.9

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

662023462024332025
From 2023 to 2025, the reported count went from 66 to 33 spills. The highest count was 66 in 2023 and the lowest was 33 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
202533362.6 hours88%Low coverageOfficial data
202446533 hours96.1%Official data
202366825.8 hours93.7%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
Thames Water
Outlet type
Storm tank at a wastewater treatment works
Permit
CNTM.1402
Activity reference
1 activity on permit
Grid reference
TQ2901040280
Waterbody ID
GB106039017500Official 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 0.6 km north-west of the Tinsley Green 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 Crawley STW

Who operates Crawley STW?
Thames Water is the operator named in the annual record. The permit reference is CNTM.1402.
Where does Crawley STW discharge?
The source names Tributary of Gatwick Stream as the receiving water. This does not show how far a discharge travelled.
How many times did Crawley STW spill in 2025?
The 2025 return records 33 counted spill events and 362.6 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 88% of the reporting period. Below 90%, some events can be missed, so the count and hours may understate activity.
Is Crawley 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 Crawley 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 Crawley STW compare with other overflows?
Crawley STW recorded 33 spills in 2025. That is more than 77% of the 14,239 overflows in England with a reported figure, and ranks 3,116th nationally. Among Thames Water overflows it ranks 92nd of 579; the median Thames Water overflow recorded 6 spills. 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.