First and foremost, the ability to look good naked is your own personal pref., saying it is a needxed skill to be a lifeguard is fucking retarded.
Secondly, to Gregron, try swimming an open water five hundred in riptide heavy waters in under ten minutes. Hint, it would probably take you over twenty if you consider yourself a decent swimmer. The physical requirements to be an ocean lifeguard are pretty fucking stringent.
For the program, I would lift three days a week for no more than an hour, focus on shoulder stability and range of motion, anti rotation for the core and compound posterior chain movements like dl's. Keep benching to a min imum, but dont omit it completely, you dont want to create imbalances. I would start with three sets of 6-8 and see how yall respond. As you progress, the sets would grow and reps per set would decline. Superset to keep the pulse high and avoid unec. weight gain.