Sewage Map

Ripley STW

Storm overflow operated by Thames Water. The source names River Wey/OCKHAM Mill Stream as the receiving water.

37
Spills in 2025
428.3
Recorded hours
94.5%
Monitor operation
5
Years listed

The reported spill count was 6 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

Ripley STW recorded 37 spills in 2025. That is more than 80% of the 14,239 overflows in England with a reported figure, and ranks 2,695th nationally. Among Thames Water overflows it ranks 77th of 579; the median Thames Water overflow recorded 6 spills. On the Wey (Shalford to River Thames confluence at Weybridge) waterbody it ranks 1st of 5.

GroupRank by spillsMedian spillsMedian hours
This outlet–37428.3
England2,695th of 14,2391122.3
Thames Water77th of 579620.9
Wey (Shalford to River Thames confluence at Weybridge)1st of 512133.2

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

212021132022222023432024372025
From 2021 to 2025, the reported count went from 21 to 37 spills. The highest count was 43 in 2024 and the lowest was 13 in 2022.
YearSpillsDurationMonitor operationSource
202537428.3 hours94.5%Official data
202443380.8 hours99.6%Official data
202322160.3 hours99.9%Official data
20221382.2 hours99.9%Official data
202121155.8 hours98.7%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, with treatment
Permit
CTCR.2150
Activity reference
A2
Grid reference
TQ0449057320
Waterbody ID
GB106039017630Official 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 - with treatment”: storm tank at a wastewater treatment works, with treatment. The overflow comes from storm storage at a treatment works. The return records this variant as discharging with treatment.

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 0.9 km north of the Ripley (Guildford) 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 Ripley STW

Who operates Ripley STW?
Thames Water is the operator named in the annual record. The permit reference is CTCR.2150.
Where does Ripley STW discharge?
The source names River Wey/OCKHAM Mill Stream as the receiving water. This does not show how far a discharge travelled.
How many times did Ripley STW spill in 2025?
The 2025 return records 37 counted spill events and 428.3 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 94.5% of the reporting period, so the annual figures cover most of the year. They still do not measure discharge volume.
Is Ripley 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 Ripley STW?
The annual return lists the asset type as “Storm tank at WwTW - with treatment”, which means storm tank at a wastewater treatment works, with treatment. The overflow comes from storm storage at a treatment works. The return records this variant as discharging with treatment.
How does Ripley STW compare with other overflows?
Ripley STW recorded 37 spills in 2025. That is more than 80% of the 14,239 overflows in England with a reported figure, and ranks 2,695th nationally. Among Thames Water overflows it ranks 77th of 579; the median Thames Water overflow recorded 6 spills. On the Wey (Shalford to River Thames confluence at Weybridge) waterbody it ranks 1st of 5. 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.