Honicknowle Lane CSO Plymouth

Storm overflow operated by South West Water. The source names Ham Brook as the receiving water.

31
Spills in 2025: 24.9
Recorded hours: 93.3%
Monitor operation: 5
Years listed

Current status unknown

Checking the latest monitor report…

How it compares in 2025

Honicknowle Lane CSO Plymouth 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 South West Water overflows it ranks 538th of 1,357; the median South West Water overflow recorded 21 spills.

Group	Rank by spills	Median spills	Median hours
This outlet	–	31	24.9
England	3,344th of 14,239	11	22.3
South West Water	538th 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 82 to 31 spills. The highest count was 82 in 2021 and the lowest was 11 in 2024. The monitor worked for less than 90% of 2022, 2024, 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	31	24.9 hours	93.3%	Official data
2024	11	3.9 hours	84.1%Low coverage	Official data
2023	78	196.5 hours	98.5%	Official data
2022	42	152 hours	88%Low coverage	Official data
2021	82	173 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 overflow on the sewer network
Permit: 301712
Activity reference: A1
Grid reference: SX47045795
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 “SO on sewer network”: storm overflow on the sewer network. The return places this overflow on the sewer network.

Where it is

The recorded position is about 2.1 km west of the Plymouth 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.

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Other outlet records nearby

Shirley Gardens CSO Plymouth
South West Water · Ham Brook
Current status unknown

St. Pancras Avenue CSO Plymouth
South West Water · Tributary of Ham Brook
Current status unknown
Ham Woods Ham Lane CSO Plymouth
South West Water · Ham Brook
Current status unknown
R/O Quarry Cottages CSO Honicknowle Ln
South West Water · Honicknowle Stream (S)
Current status unknown

Questions about Honicknowle Lane CSO Plymouth

Who operates Honicknowle Lane CSO Plymouth?: South West Water is the operator named in the annual record. The permit reference is 301712.
Where does Honicknowle Lane CSO Plymouth discharge?: The source names Ham Brook as the receiving water. This does not show how far a discharge travelled.
How many times did Honicknowle Lane CSO Plymouth spill in 2025?: The 2025 return records 31 counted spill events and 24.9 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 93.3% of the reporting period, so the annual figures cover most of the year. They still do not measure discharge volume.
Is Honicknowle Lane CSO 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 Honicknowle Lane CSO Plymouth?: The annual return lists the asset type as “SO on sewer network”, which means storm overflow on the sewer network. The return places this overflow on the sewer network.
How does Honicknowle Lane CSO Plymouth compare with other overflows?: Honicknowle Lane CSO Plymouth 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 South West Water overflows it ranks 538th 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.