Punahou was an established, pricey, private college preparatory school near the University of Hawaii Campus with one of the top sports programs in the country.

[12] On August 2, 1997, he placed second in the USA Swimming Open Water National Championships 5 Km event at Percy Priest Lake in Nashville Tennessee with a time of 50:17.

[2] On June 5, 1999, he placed third in a field of nineteen in the USA Swimming Open Water National Championships 25 Km event at Hawaii Cay to Waikiki at Honolulu with a time of 4:35:54.

[2] On July 10, 1999, he placed second in the USA Swimming Open Water National Championships 10 Km event at Newport Beach, California with a time of 2:08:11.

[2] On August 17, 2000, he placed third in the USA Swimming Open Water National Championships 5 Km event at Eagle Creek Reservoir in Indianapolis, Indiana with a time of 53:29.

In a rough current, Flanagan pulled ahead of Heltzel in the final 200 yards of the race, clinching an impressive win in an elite field of 38.

[14] In September 2000, Flanagan won the 2.5 mile Waikiki Roughwater Swim from Sans Sousi to Duke Kohonomoku Beach with a time of 48:58.

[3] In July 2000, he comfortably won the local 2.4 Open Water Surf and Sea North Shore Challenge, from Ehukai Beach Park to Waimea Bay in a record time of 39:05.7.

[2] On June 24, 2001, he won the USA Swimming Open Water National Championships 10 Km event at Daytona Beach, Florida with a time of 2:01:58.

[19] On July 16, 2001, he placed fourth in the Men's 10 Km Open Water competition at the World Championships at Fukuoka, Japan, with a time of 2:01:16.5[20] By the age of 35, around 2010, John had attempted and performed well in a number of triathlons as a professional.