SARA HAD RECENTLY perfected the art of “French laps.” This is a routine in which the athlete paddles up and down the length of the pool in an inflatable easy chair, a glass of pastis in the cupholder. With the days getting hotter, we were thirsty for more water sports. The pool, however, had turned strangely cloudy.

“Papa?” said Sara.

“Oui, ma fille?”

“Can we go canoeing instead?”

I resisted the urge to say, Are you nuts? I’m way too old for an extreme sport like canoeing! The truth is, I was...