The 34-year-old, who took gold for Britain at the 2006 ITU Triathlon World Championships in Lausanne, will be up against American rival Jarrod Shoemaker, another former world champion, who also competed in the 2008 Beijing Olympics.
It is the first time Mr Don, who has competed as a triathlete at three Olympic Games, is taking part in the race.
Mr Don said: “Obviously many will be just finishing work and it’s a little out of the norm to have a triathlon taking place around your office, so I can imagine there will be a fair few interested parties, especially if the weather stays nice and sunny.”
More than 60 professional triathletes will test their endurance during two races consisting of a 400m swim in the Middle Dock, a 10km cycle race and a 2km run around Canary Wharf’s North and South Colonnades.
Chelsea Old Town Hall will be the venue for the renowned Desire Fair from 6-8 March 2015. This stunning mixed media jewellery and silversmithing event where visitors can purchase direct from contemporary designer makers selected from the best in the UK is an event not to be missed.