Sewage Map

Great Clifton

Storm overflow operated by United Utilities. The source names River Derwent as the receiving water.

16
Spills in 2025
162.2
Recorded hours
75.7%
Monitor operation
2
Years listed
Current status unknown

We do not have a live report for this outlet. Its annual spill records are shown below.

Open official annual data ↗

How it compares in 2025

Great Clifton recorded 16 spills in 2025. That is more than 58% of the 14,239 overflows in England with a reported figure, and ranks 5,789th nationally. Among United Utilities overflows it ranks 1,105th of 2,270; the median United Utilities overflow recorded 15 spills. On the Derwent - conf Cocker to tidal waterbody it ranks 12th of 14.

The monitor worked for 75.7% of 2025, so this count may be low and its rank may understate activity.

GroupRank by spillsMedian spillsMedian hours
This outlet–16162.2
England5,789th of 14,2391122.3
United Utilities1,105th of 2,2701529.1
Derwent - conf Cocker to tidal12th of 1479.5289.4

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

1502024162025
From 2024 to 2025, the reported count went from 150 to 16 spills. The highest count was 150 in 2024 and the lowest was 16 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
202516162.2 hours75.7%Low coverageOfficial data
20241501,585.1 hours99.7%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
United Utilities
Outlet type
Inlet storm overflow at a wastewater treatment works
Permit
Unpermitted
Activity reference
A1
Grid reference
NY0329029860
Waterbody ID
GB112075070520Official 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 0.8 km west of the Great Clifton 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 Great Clifton

Who operates Great Clifton?
United Utilities is the operator named in the annual record. The permit reference is Unpermitted.
Where does Great Clifton discharge?
The source names River Derwent as the receiving water. This does not show how far a discharge travelled.
How many times did Great Clifton spill in 2025?
The 2025 return records 16 counted spill events and 162.2 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 75.7% of the reporting period. Below 90%, some events can be missed, so the count and hours may understate activity.
Is Great Clifton discharging right now?
This record is not matched to a company live feed, so we cannot show a current report. Only the annual figures are available for this outlet.
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 Clifton?
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 Clifton compare with other overflows?
Great Clifton recorded 16 spills in 2025. That is more than 58% of the 14,239 overflows in England with a reported figure, and ranks 5,789th nationally. Among United Utilities overflows it ranks 1,105th of 2,270; the median United Utilities overflow recorded 15 spills. On the Derwent - conf Cocker to tidal waterbody it ranks 12th of 14. 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.