Oahu's fabled north shore is not only the home of pro surfing's Triple
Crown contests but the birthplace of tow-in surfing, in which personal
watercraft help athletes drop in on waves up to 50 ft. tall. It's also
where lifeguards developed a two-person rescue system using PWCs. Elite
rescue-craft operator Guy Pere performs about 20 saves per year (mostly
during the treacherous winter), but says prevention—stopping the guy
with the rental surfboard—is his top priority. "If I just sat there and
let everyone go in the water, well, I'd probably never have lunch."