The Windsor Triatlon on will be cut back today to a duathlon for the first time in 22 years.
The heavy rainfall meant organisers liased with the Environment Agency this week over the high river levels and speed of the current in the River Thames.
A statement on the event's website said: "The recent exceptional rainfall and unseasonal weather has meant that the river flow is still increasing and further significant rainfall in the River Thames catchment area is expected over the coming days.
It added: "With your safety uppermost in our thoughts, we have made the difficult decision to switch to our contingency plan and we are therefore cancelling the swim element of the triathlon and replacing it with a 1000m first run. This will be the first time in twenty-two years that we have had to do this.
It has offered all Windsor competitors a free place in the Speedo Winsdor Swim in the Thames on Sunday, July 8. Details will be emailed to the entrants next week.
The race will go ahead as a duathlon as follows:
Sprint: 1000m run; 30km bike; 5km run
Olympic (full): 1000m run; 42km bike; 10km run
See next week's Express for a full report.
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