Lucky Lifeguard by Amelia C. Adams

Joey Peterson works at the River’s End Ranch pool during the summer to earn money for college in the fall. His job as a lifeguard is fun and rewarding, although his real dream is to practice sports medicine. He’ll get there . . . one semester at a time.
Chelsea McAllister is an Olympic-hopeful swimmer who damaged her knee on a training run. Looking for a place where she can recover while they celebrate their anniversary, her parents book a trip to River’s End Ranch, not realizing that Chelsea’s ex-boyfriend Joey now works there.
It’s been two years since Joey and Chelsea have seen each other, and they didn’t part on good terms. Hopefully enough time has gone by to wash the old wounds . . . and that it’s all water under the bridge.