Toxic Algae Hits First Thames Bathing Spot in London
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- The Environment Agency posted a sign at the Ham bathing site warning swimmers not to enter the water after toxic blue-green algae were detected — the first such occurrence in nearly six years of swimming at the spot, which was designated under the EU water framework directive in May.
- Blue-green algal blooms are rare in moving water and likely caused by extreme heat, low river flow, and nutrient pollution from sewage waste, according to the article.
- Thames Water is advancing a £250m scheme to abstract 75m litres of water daily from the Thames at Teddington during drought and replace it with treated sewage from the Mogden works via a new tunnel — designated strategic infrastructure, meaning it can bypass local authority approval.
- The Environment Agency previously rejected an earlier version of Thames Water's recycling scheme, ruling the treated sewage would raise water temperatures during low flow, change salinity, and harm biodiversity.
- Thames Water has been in breach of its Hogsmill permit conditions, discharging raw sewage illegally, and postponed promised Hogsmill upgrades until at least 2028 — now under Ofwat investigation.
- Campaigners argue the recycling project offers just 75m litres a day — a fraction of the 570m litres Thames Water leaks daily — while adding environmental pressure to the river.
- Marlene Lawrence of swimming group Teddington Bluetits said the algae 'shows that the river is under stress from the drought and high temperatures' and warned climate change will make such events more likely.
Why it matters: The algae warning lands as Thames Water — £20bn in debt and under Ofwat investigation for permit breaches and postponed Hogsmill upgrades — pushes a £250m recycling scheme the Environment Agency previously rejected for raising river temperatures during low flow, while the company leaks 570m litres of water daily.
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