The International Ice Swimming Association (IISA) Aotearoa New Zealand National Open Water Champs start in the historic man-made lake today.
It is the first "official" open water ice swimming nationals to take place in New Zealand — in 2021 an ice swim at Lake Lyndon, near Christchurch, was the catalyst for the inaugural ice swimming pool championships in Alexandra last year.
Ice swimming standards state swimmers can wear only a silicon cap, pair of goggles and a standard swimming costume.
With the water temperature required to be below 5degC to count towards official results, that is no mean feat — and not without risk, IISA Aotearoa New Zealand events director Susan Sherwen said.
"Each degree you go down under 5degC you kind of exponentially increase the risk and how bad it is ...
"The main dangers are when they go in — the cold gives you that gasp reflex, so if you go in and go under water and breathe in you can actually sort of drown in that little bit," she said.
With yesterday’s water temperature sitting at just over 4degC, organisers are hoping to avoid a repeat of last year where temperatures rose above 5degC because of rain, voiding results.
Almost 40 swimmers — nearly double the number from last year — are set to take part in the four-day event, competing in 250m, 500m, 1000m and one mile swims.
Ms Sherwen will attempt to complete a 2km swim, known in the sport as an "extreme ice mile".
"We’re going to have a lot of fun — there’s a lot of very nervous people coming down that are excited to challenge themselves in extreme conditions."
Internationally, ice swimming is an activity in about 70 countries — mostly in the northern hemisphere — and is aiming to become a Winter Olympic sport.
In New Zealand, it became one of the hottest new extreme sports when Covid-19 restrictions forced swimmers out of swimming pools and into lakes and the ocean.
