Fencing that prevents access to a toxic algae which is potentially fatal for dogs has been lifted at Ruislip Lido.
The site near Harrow and Rickmansworth is popular on sunny days but following the heatwave in July, there was an outbreak of blue-green algae.
Under government guidance, Hillingdon Council had to close the water off to the public as a precaution to ensure people and pets stay out of the water.
Now the toxic algae has lessened and the fencing has been removed, however people are reminded to still not go in the water due to its depth, general safety and hygiene concerns and the possibility of blue-green algae remaining.
The bloom of blue-green algae naturally occurs in hot and sunny weather and the Environmental Agency states that it can produce toxins that could kill animals, livestock and pets.
The agency said: "They can also harm people, producing rashes after skin contact and illnesses if swallowed."
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