Father’s Day won’t only be celebrated this Sunday by the Cole family. It will be extended through next Saturday when three generations compete in the Aloha Salads Summer Sprint, the opener of the Surf N Sea North Shore Swim Series.

What began as a bit of a bribe — Schuyler “Lucky” Cole paid the entry fees for his son and grandson to do the series — is becoming a tradition in the making. Cole, son Christopher and grandson Schuyler will be in the water together for the second straight year.

“It was a way to get them to the North Shore (from Palolo Valley) at least four times a summer,” the 72-year-old patriarch from Sunset Beach said. “I’m really proud of them. I’m a little frugal and I had hoped my investment wouldn’t be a waste. It hasn’t at all.”

Last year, all three placed in the top three of their age groups in all four of the events and all finished second overall. It was quite an accomplishment, particularly since Schuyler, then 11, had just begun competitive swimming.

“I had just started and thought I’d try it out with my dad and grandpa,” Schuyler, an incoming seventh-grader at Punahou, said. “The swims are beautiful, seeing all the sea life there when you’re swimming.

“It’s cool that we’re doing it. It’s going to be really fun again.”

The Coles come from a family of watermen. Lucky Cole’s older brother Peter, a legendary big-wave surfer in the 1950s, was inducted into the Hawaii Waterman Hall of Fame last August. The brothers grew up surfing and swimming in Southern California with Lucky going on to swim and play water polo for Santa Monica College and UCLA.

Christopher Cole, 47, played basketball at Waialua High but “growing up on the North Shore, we were always surfing and in the water,” he said. “I did the Fourth of July swim across Waimea Bay when I was younger and did some of the swim series, a race here and there, before it got really big.

“My dad started signing me up about five years ago, to get us to go visit, and I’ve pretty much done all four events since then. Now with my son, it’s something we all get to share.”

As ocean swimming continues to gain in popularity, so has the North Shore Swim Series, entering its 23rd year. Each of the four 2011 races drew more than 700 swimmers and like numbers are expected.

In last year’s 1-mile series opener, Christopher was the first to finish (28:27) while Schuyler (38.00) edged out his grandfather (38:17). The only time there was more than a 2-minute gap between grandfather and grandson was in the 2.3-mile series finale win Schuyler veered off course and finished nearly 10 minutes behind Lucky.

“What’s really nice is continuing the family tradition of being watermen,” Christopher Cole said. “We live on an island. We should be in the water.”

Also joining in for the first time will be Schuyler’s siblings — Dylan, 11, and Mahina, 10.