Elevated and potentially toxic levels of blue-green algae currently forming in Alton Water have led to the popular Great East Swim being postponed until later this year.
Organisers have said they can no longer safely hold the event, which was supposed to take place on Saturday, June 19.
A spokesperson for the event, said: "We are sure, like us, our swimmers are disappointed about this news, and after almost two years of no Great East Swim events we are hugely disappointed that we have had to do this."
The event will now take place on Saturday, September 25 and entries will be automatically rolled over to the new date. However, if you are unable to take part on the new date you will be offered a refund.
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