VISITORS are being advised to stay out of the water at Frensham Great Pond, after high levels of blue-green algae were detected.
The algae can be toxic to dogs, so visitors are also advised to keep them out of the water.
Contact with water containing high levels of blue-green algae can cause illness in humans, including skin irritation.
Swallowing the water or algal scum can cause vomiting, diarrhoea, fever, and pains in muscles or joints.
A post on the Frensham Great Pond and Common Facebook page, run by Waverley Borough Council, read: “If you have been in contact with the water at the pond you should wash your hands well before eating, drinking or smoking. Shower as soon as you can after exiting the water.
“If you have any signs of skin rash, stomach pains or vomiting after being in the water please seek medical advice.
“We will continue to monitor the levels of blue-green algae and will let you know as soon as it’s safe to enter the water at the big pond. Thank you for your co-operation.”
Last year it took around seven weeks for the algal analysis report to show the levels of blue-green algae were safe.
However, it can take less time depending on the weather and other environmental factors.
The site and its facilities remain open as usual.