1) Becomes flooded with 2) Begins a triathlon 3) Crawls 4) Dips in pools 5) Does laps 6) Does laps in a pool 7) Does the backstroke 8) Does the butterfly 9) Does the crawl 10) Does the crawl or butterfly 11) Does the dog paddle 12) Dog-paddles 13) Emulate ederle 14) Emulates ederle 15) Emulates Heiden Found on https://www.crosswordclues.com/clue/swims