London's first official bathing site on the River Thames has been temporarily closed to swimmers due to the presence of toxic blue-green algae. The Ham and Kingston bathing site, which opened in Kingston upon Thames in May, is now subject to an advisory against bathing.
The Environment Agency has also issued warnings for locals to avoid a broader section of the Thames between Hampton and Kingston, as this area is also likely affected by the algal bloom. The agency stressed the importance of keeping dogs away from the affected waters, as the toxins can be harmful to animals.
Blue-green algae, also known as cyanobacteria, thrives in warm temperatures, low rainfall, and calm water conditions. These blooms can produce toxins that pose risks to humans and animals, potentially causing skin rashes and illness if ingested. The agency has reported an increase in algal blooms and deteriorating water quality during periods of drought and dry weather.
The Ham and Kingston site is one of several new locations designated for open water swimming and is subject to regular water quality testing until the end of September. Signage has been erected at the site to alert the public. The Environment Agency is collecting water samples to determine the full extent of the algal bloom.
The UK Health Security Agency and relevant abstractors have been notified of the situation.