Swimmers taking part in the iconic Rottnest Channel Swim this Saturday (26 February) will be able to design a personalised, optimised route for their crossing that can be uploaded to their GPS, Garmin watch or the Rotto Swim app.

The Route Optimisation Tool, the result of a collaboration between The University of Western Australia, Aurora Offshore Engineering and the Rottnest Channel Swim Association, is designed to help swimmers maximise performance on the day.

"We use forecast currents from the UWA Oceanography Group, together with swimmers' predicted pace, to work out the optimum route that they should take."

Associate Professor Scott Draper, UWA Oceans Graduate School

Associate Professor Scott Draper from UWA’s Oceans Graduate School said the online tool, available on the Rottnest Channel Swim website, creates a customised route for swimmers based on their ability and expected conditions on event day.

“We use forecast currents from the UWA Oceanography Group, together with swimmers’ predicted pace, to work out the optimum route that they should take,” he said.

“Often in the swim you’ll have quite strong currents either from the north or from the south. So if you try to swim directly from Cottesloe to the island, you’re going to lose a lot of energy to stay on that course which will affect your time.”

Director at Aurora Offshore Engineering Terry Griffiths said currents were often the strongest in the final leg of the gruelling 19.7km open water race as competitors approached Rottnest.

“Adjusting their route to accommodate these can lead to a quicker and safer event for swimmers,” Mr Griffiths said. “By using a mathematical algorithm and with the information provided on currents and predicted swim pace we’re able to do this,” he said.

For Shenton Park resident and UWA Doctor of Optometry student Olivia Stewart, 21, the new tool is welcome news as she prepares to compete in her fifth Rottnest Channel Swim. 

Image: UWA student Olivia Stewart will use the Route Optimisation Tool to plot her course for Saturday's swim.

“Dad’s my skipper and we usually sit down the night before to try and plot my route but it’s always difficult, particularly if currents are going to be strong,” Olivia said. 

“Now all I have to do is go to the website and enter my predicted pace, along with some information on feeding intervals and duration, and it calculates a route which Dad can upload to his iPad.”

Rottnest Channel Swim Association Executive Officer Nic Blackburn said the web application would also assist with swimmers’ safety as they underwent the ultimate test of endurance.

“In the past the strong currents have pulled swimmers into the rescue corridor which needs to be kept clear for boats, meaning they’ve had to be pulled from the water, and it’s also seen competitors swimming statically at around the 17km mark and getting nowhere,” Mr Blackburn said.

“We’re thrilled that this new tool is available for all because ultimately it’s going to allow for a safer event and for more people to make it to Rottnest.”

Associate Professor Draper, a regular competitor in the swim, said early predictions were that there would be fast currents on the day.

“At the moment currents are looking similar to last year and are to the north and quite strong,” he said. “That’s a long-range forecast so it may improve, but at present the Route Optimisation Tool could be really quite important given the strong currents forecasted.”