Sewage Map

Harborough Magna STW (CSO)

Storm overflow operated by Severn Trent Water. The source names Little Lawford Brook as the receiving water.

31
Spills in 2025
69.1
Recorded hours
100%
Monitor operation
6
Years listed

The reported spill count was 11 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

Harborough Magna STW (CSO) recorded 31 spills in 2025. That is more than 75% of the 14,239 overflows in England with a reported figure, and ranks 3,344th nationally. Among Severn Trent Water overflows it ranks 355th of 2,431; the median Severn Trent Water overflow recorded 8 spills. On the Avon - ClaycotonYelvertoft Bk to conf R Sowe waterbody it ranks 1st of 13.

GroupRank by spillsMedian spillsMedian hours
This outlet–3169.1
England3,344th of 14,2391122.3
Severn Trent Water355th of 2,431816.2
Avon - ClaycotonYelvertoft Bk to conf R Sowe1st of 13418.9

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

99202022720212322022282023422024312025
From 2020 to 2025, the reported count went from 99 to 31 spills. The highest count was 232 in 2022 and the lowest was 28 in 2023. The monitor worked for less than 90% of 2021, so that count may be low.Amber bars mark years when the monitor worked for less than 90% of the year.
YearSpillsDurationMonitor operationSource
20253169.1 hours100%Official data
202442114.4 hours100%Official data
20232842.3 hours100%Official data
2022232493.6 hours100%Official data
2021227365.5 hours87.8%Low coverageOfficial data
202099379.7 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
Severn Trent Water
Outlet type
Inlet storm overflow at a wastewater treatment works
Permit
S/10/26277/R
Activity reference
A2
Grid reference
SP4748078340
Waterbody ID
GB109054043920Official 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 2.4 km north of the Long Lawford 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 Harborough Magna STW (CSO)

Who operates Harborough Magna STW (CSO)?
Severn Trent Water is the operator named in the annual record. The permit reference is S/10/26277/R.
Where does Harborough Magna STW (CSO) discharge?
The source names Little Lawford Brook as the receiving water. This does not show how far a discharge travelled.
How many times did Harborough Magna STW (CSO) spill in 2025?
The 2025 return records 31 counted spill events and 69.1 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 Harborough Magna STW (CSO) 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 Harborough Magna STW (CSO)?
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 Harborough Magna STW (CSO) compare with other overflows?
Harborough Magna STW (CSO) recorded 31 spills in 2025. That is more than 75% of the 14,239 overflows in England with a reported figure, and ranks 3,344th nationally. Among Severn Trent Water overflows it ranks 355th of 2,431; the median Severn Trent Water overflow recorded 8 spills. On the Avon - ClaycotonYelvertoft Bk to conf R Sowe waterbody it ranks 1st of 13. 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.