A triathlon’s swimming segments have been cancelled due to fears over water quality.

The Castle Race Series was set to take place at Hever Castle this weekend.

However, after a week of heavy rainfall, the decision was made to remove the swimming portion of the event due to overflow and runoff being discharged into Hever Lake.

At a meeting of their Swim Advisory Committee on Thursday, it was revealed that recent tests indicated the water was unsafe to swim in.

A statement from the Caste Race series said: “We have made the difficult decision to cancel all swim segments for the event taking place on 28-29 September at Hever Castle.

“We understand how disappointing this news will be, especially given the training and preparation participants will have done for the swim section of their race, but the safety and well-being of participants is always the top priority.

“We look forward to welcoming you to Hever this weekend for what promises to be a great event despite this unexpected change.”

The triathlons will now be changed to a duathlon format, which includes two running sections instead.

Aquabike and aquathlon events will now also change to a single discipline event. All Swim Series events have been cancelled.

Last year athletes who took part in the triathlon were left “bed-bound” with nausea and diarrhoea.

The race organisers say water quality tests carried out before the event showed it to be safe, but an investigation was launched following a number of reports of sickness.

The spokesman explained the Castle Race Series water tests begin six weeks before any race is due to take place and then again four weeks before. Another one is done two weeks prior to the race.

The water samples are taken from the body of water and the tests are conducted in a lab to test for both E. coli and Enterococci to ensure that the water quality is safe to swim in.

In the week leading up to the event, these tests are carried out once every morning.