Designated bathing water · official register
Hampstead Heath (Mixed Pond)
City and County of the City of London
The Environment Agency's classification is good and no short-term pollution warning is active. Based on the EA classification Excellent (2025) and no active short-term pollution warning.
Latest EA sample· 26 Jun 2026
280
E. coli · cfu/100ml
<10
Intestinal enterococci · cfu/100ml
Storm overflows within 5.0 km
Monitored sewage discharge points near this bathing water, from the National Storm Overflow Hub. An active spill upstream can affect water quality before it shows up in lab samples.
13
Storm overflows
0
Spilling now
1
Monitors offline
0
Spills · 24 h
- Thames Water · TWL00591 · Dollis Brookoffline2.7 km
- Thames Water · TWL00574 · Dollis Brookinactive3.4 km
- Thames Water · TWL00320 · Decoy Brookinactive3.2 km
- Thames Water · TWL00590 · Dollis Brookinactive3.2 km
- Thames Water · TWL00225 · Decoy Brookinactive3.6 km
- Thames Water · TWL00321 · Decoy Brookinactive3.6 km
- Thames Water · TWL00613 · Dollis Brookinactive4.0 km
- Thames Water · TWL00484 · Dollis Brookinactive4.3 km
- Thames Water · TWL00053 · River Brentinactive4.0 km
- Thames Water · TWL00491 · River Brentinactive4.0 km
About this verdict
The classification, lab samples and pollution warnings above are the Environment Agency's own published data for this designated site; River Truth adds live storm-overflow context from the National Storm Overflow Hub. Sample results reflect water quality at the time of testing and this page is not formal bathing advice — heed any on-site signage.