There's no questioning that Kal-El could survive long underwater, and the first Man of Steel teaser trailers showed he'd be spending some time seaward, bearded, and stinking of crab before becoming the hero we know him to be.
The trailer's footage of Clark bathed in fire, sporting Hulk-pants, and flying off into the sunset (alight?) confirms that a catastrophe in his wandering life will force him to accept his gifts - not hide them. The passing school bus in the maritime setting is also a nice callback to what looks to be Clark's first heroic rescue.
For those fans who were a little turned off by the idea of Superman wasting some time aboard a fishing vessel before becoming a full-blown Man of Steel, it seems there is at least a sizable action sequence to look forward to. And for hardcore fans, the look of actual effort and pain on Cavill's face promises a Superman who actually has to put his back into his super-strength.