A popular triathlon could be disrupted for the second year running over fears blue green algae health hazard.
Entries for the 2025 Mourne Sprint Triathlon in Castlewellan Forest Park in County Down have now been postponed due to concerns organisers say.
Contact with blue green algae can damage the health of humans and animals.
The potentially harmful algae has appeared in Castlewellan lake in recent weeks.
It has also been spotted in other areas, including Lough Neagh, where large areas were covered in the potentially toxic substance in recent years.
Triathlon organiser Chris Campbell believes the water quality at Castlewellan may not be up to standard by the time the planned race is held in August.
The lake would be used for the swimming leg of the event.
“I’m not confident it will go ahead at all this year,” he said.
“We would need a lot of rain to clear it.”
Olympian Triathlon Belfast said it was looking into alternative venues for the event.
Mr Campbell added “the fear is, blue green algae could be a problem at any bathing site in Northern Ireland”,.
“It doesn’t seem to us that much is being done about this.”
Newry Mourne and Down District Council is continuing to monitor conditions in the lake and has warned members of the public not enter the water, drink the water, catch or eat fish from the lake.
People have also been advised to keep animals away from the lake.
The annual race was impacted last year after Newry, Mourne and Down said the water would not be safe.
At that stage around 400 entries had been received and a decision was taken to adapt the event rather than call it off.
Mr Campbell said it was very disappointing that a similar position may arise this year.
Stephen Chisholm from Belfast was due to take part in the 2024 race but did not compete in the duathlon.
“Taking the swim element out for me was removing a huge part of the challenge”, he said.
“Triathlon is unique in that it’s three sports one after the other and it’s not often that someone can do all three back-to-back or even in a single day.”
“This was to be my final official race of the year and one last chance to see the results of my training throughout the year”, he said.
“I love open water swimming and Castlewellan is a stunningly beautiful location so it was a real shame to miss this.”
