The word waterfronts is playable in Words With Friends™, no blanks required. Because it is longer than 7 letters, you would have to play off an existing word or do it in several moves.
Words With Friends™ Letter Score: 18
Highest Scoring Words With Friends™ Plays In The Letters
Seven Letter Word Alert: (37 words)
atoners, errants, fattens, foresaw, forwarn, forwent, fraters, froster, frowner, narrows, natters, ornater, rafters, ranters, ratters, rattons, reroast, restart, retoast, retorts, roaster, rotates, rotters, seaworn, senator, snorter, snotter, starter, swatter, tarrows, toaster, torrent, treason, twofers, wafters, wanters, warners