The Serpentine - Hyde Park — Bathing Water Quality 2025

Classification history

2020 excluded (COVID-19 cancelled the bathing season). Source: EA BWQ API.

The Serpentine - Hyde Park — FAQ

Is The Serpentine - Hyde Park safe to swim?

The Serpentine - Hyde Park is rated Good for the 2025 bathing season — the second highest EA rBWD classification, indicating consistently good water quality. It is safe to swim under normal conditions. Always check the EA for real-time advisories after heavy rainfall.

What does Good classification mean?

Good is the second-highest EA rBWD classification. The site meets high water quality standards but may have occasional minor exceedances. Safe for swimming under normal conditions.

What is the Gera Bathing Water Score?

The Gera Bathing Water Score (GBWS) combines two components from Environment Agency rBWD annual compliance classifications (key-free open data, OGL v3.0): (1) latest classification score (Excellent=100, Good=75, Sufficient=50, Poor=25), weighted 0.6; and (2) pass-rate across every assessed season available for the site (up to six: 2019, 2021–2025; the proportion rated Sufficient or above), weighted 0.4. Formula: GBWS = round(0.6 × latest_score + 0.4 × pass_rate × 100). Sites with fewer than 3 assessed seasons are shown as 'insufficient data'. The 2020 bathing season was cancelled due to COVID-19 and is excluded. LA-level scores are the mean GBWS of all sites within the LA that have sufficient data. Source: EA BWQ API, seasons 2019, 2021–2025.

Who monitors The Serpentine - Hyde Park?

The Serpentine - Hyde Park is a designated bathing water in City of Westminster, monitored by the Environment Agency. It is an inland bathing water. The EA takes regular water samples during the bathing season (May–September) and publishes weekly results at environment.data.gov.uk/bwq/. The annual classification is published after the season closes.