Career
Williamson competed at the first Olympic triathlon at the 2000 Summer Olympics. She took twenty-second place with a total time of 2:05:38.30. Williamson placed 3rd at the 1998 International Telecommunication Union Triathlon World Championships.
Williamson qualified as the alternate for the 2008 Beijing Olympics, but as New Zealand does not send their alternates along with the three-person team, she did not attend.