Update 7 August
A spokesperson for the Environmental Agency said, “We thought that we’d let your readers know that on Sunday 5 August we investigated reports of possible blue green algae on the River Thames south of Marsh Lock between Henley-on-Thames and Shiplake. We took a water sample from the River for analysis. No blue green algae was found in the sample. Open waters are not considered to be of bathing water standard and we would encourage people to read Public Health England’s advice on reducing the risk of illness when open water swimming https://www.gov.uk/government/publications/swim-healthy-leaflet”
If people do think they see blue green algae in not just the Thames but in any stream, lake, pond etc, we encourage the public to report that on 0800 807060
Reports are coming in about local dogs who have swam in the river becoming ill afterwards.
It is thought they have been affected by the build-up of blue-green algae in the hot weather around the edges of the river.
Animal charity, Blue Cross have issued this following advice:
The bacteria cannot be seen with the naked eye unless they clump together. When this happens, blue-green algae can look like green flakes, greenish bundles or brown dots. When the algae blooms, it can give look like a blue-green scum has appeared on the surface of the water. It sometimes looks a bit like pea soup.
Blooms of blue-green algae can produce harmful toxins which stop a dog’s liver from functioning properly. However, not all types of blue-green algae are dangerous.
Sadly, exposure to toxic blue-green algae is often fatal, and can also cause long term health problems in dogs that survive after drinking or swimming in algae-contaminated water. Some types of blue-green algae can kill a dog just 15 minutes to an hour after drinking contaminated water.
Dogs who have been swimming in water can get the algae caught in their fur, and can ingest it while cleaning themselves later on.
Contact your vet immediately if your dog shows signs of vomiting, Diarrhoea, seizures/fitting, weakness/collapse/unconsciousness, disorientation/confusion, drooling or breathing difficulties after swimming in the river.