Ernesettle STW SSO Plymouth

Storm overflow operated by South West Water. The source names River Tamar (E) as the receiving water.

47
Spills in 2025: 790.6
Recorded hours: 89%
Monitor operation: 5
Years listed

Current status unknown

Checking the latest monitor report…

How it compares in 2025

Ernesettle STW SSO Plymouth recorded 47 spills in 2025. That is more than 86% of the 14,239 overflows in England with a reported figure, and ranks 1,843rd nationally. Among South West Water overflows it ranks 362nd of 1,357; the median South West Water overflow recorded 21 spills.

The monitor worked for 89% of 2025, so this count may be low and its rank may understate activity.

Group	Rank by spills	Median spills	Median hours
This outlet	–	47	790.6
England	1,843rd of 14,239	11	22.3
South West Water	362nd of 1,357	21	39.4

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

From 2021 to 2025, the reported count went from 59 to 47 spills. The highest count was 90 in 2023 and the lowest was 47 in 2025. The monitor worked for less than 90% of 2024, 2025, so those counts may be low.Amber bars mark years when the monitor worked for less than 90% of the year.

Year	Spills	Duration	Monitor operation	Source
2025	47	790.6 hours	89%Low coverage	Official data
2024	49	840.4 hours	49.5%Low coverage	Official data
2023	90	1,455.1 hours	100%	Official data
2022	70	795.3 hours	100%	Official data
2021	59	961.8 hours	100%	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: South West Water
Outlet type: Storm tank at a wastewater treatment works
Permit: 301142
Activity reference: A3
Grid reference: SX44246023
Waterbody ID: Unknown
Location source: Official annual grid reference
Location precision: About 10 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.

Where it is

The recorded position is about 2.6 km south-east of the Cargreen reference point in the ONS built-up areas data.

Area and water pages

Plymouth area →

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

Ernesettle Lane CSO Plymouth
South West Water · River Tamar via SWS (E)
Current status unknown

Ernesettle STW So Plymouth
South West Water · River Tamar (E)
Current status unknown
Florence Street CSO Plymouth
South West Water · Weston Mill Lake(S)
Current status unknown
Tamerton Close SPS Pscsoeo Plymouth
South West Water · Tamerton Lake(E)
Current status unknown

Questions about Ernesettle STW SSO Plymouth

Who operates Ernesettle STW SSO Plymouth?: South West Water is the operator named in the annual record. The permit reference is 301142.
Where does Ernesettle STW SSO Plymouth discharge?: The source names River Tamar (E) as the receiving water. This does not show how far a discharge travelled.
How many times did Ernesettle STW SSO Plymouth spill in 2025?: The 2025 return records 47 counted spill events and 790.6 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 89% of the reporting period. Below 90%, some events can be missed, so the count and hours may understate activity.
Is Ernesettle STW SSO Plymouth 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 10 metres. It shows the recorded outlet position, not the extent of any discharge.
What kind of outlet is Ernesettle STW SSO Plymouth?: 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 Ernesettle STW SSO Plymouth compare with other overflows?: Ernesettle STW SSO Plymouth recorded 47 spills in 2025. That is more than 86% of the 14,239 overflows in England with a reported figure, and ranks 1,843rd nationally. Among South West Water overflows it ranks 362nd of 1,357; the median South West Water overflow recorded 21 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.