Sewage Map

Melksham Storm Tank

Storm overflow operated by Wessex Water. The source names River Avon as the receiving water.

20
Spills in 2025
308.1
Recorded hours
100%
Monitor operation
5
Years listed

The reported spill count was 32 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

Melksham Storm Tank recorded 20 spills in 2025. That is more than 63% of the 14,239 overflows in England with a reported figure, and ranks 5,045th nationally. Among Wessex Water overflows it ranks 454th of 1,332; the median Wessex Water overflow recorded 11 spills. On the Avon (Brist) conf R Marden to conf Semington Bk waterbody it ranks 9th of 25.

GroupRank by spillsMedian spillsMedian hours
This outlet–20308.1
England5,045th of 14,2391122.3
Wessex Water454th of 1,3321118.9
Avon (Brist) conf R Marden to conf Semington Bk9th of 25640.4

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

n/a2021n/a2022452023522024202025
From 2023 to 2025, the reported count went from 45 to 20 spills. The highest count was 52 in 2024 and the lowest was 20 in 2025.
YearSpillsDurationMonitor operationSource
202520308.1 hours100%Official data
202452970.2 hours99.8%Official data
202345788.8 hours99.6%Official data
2022UnknownUnknownUnknownOfficial data
2021UnknownUnknownUnknownOfficial 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
Wessex Water
Outlet type
Storm tank at a wastewater treatment works
Permit
101886
Activity reference
2-SETTLEMENT TREATMENT ONLY
Grid reference
ST8978063760
Waterbody ID
GB109053027440Official 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 1.2 km west of the Melksham 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 Melksham Storm Tank

Who operates Melksham Storm Tank?
Wessex Water is the operator named in the annual record. The permit reference is 101886.
Where does Melksham Storm Tank discharge?
The source names River Avon as the receiving water. This does not show how far a discharge travelled.
How many times did Melksham Storm Tank spill in 2025?
The 2025 return records 20 counted spill events and 308.1 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 Melksham Storm Tank 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 Melksham Storm Tank?
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 Melksham Storm Tank compare with other overflows?
Melksham Storm Tank recorded 20 spills in 2025. That is more than 63% of the 14,239 overflows in England with a reported figure, and ranks 5,045th nationally. Among Wessex Water overflows it ranks 454th of 1,332; the median Wessex Water overflow recorded 11 spills. On the Avon (Brist) conf R Marden to conf Semington Bk waterbody it ranks 9th of 25. 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.