Guess she decided to use the “water pump” after all.
(btw, for those that don’t knw about the semi-hidden director commentary, check the Transcript link for some… kind of out-there info.)
In early drafts of the story, all sarnothi were basically waterbenders. And just for extra super-crazy trivia, in that same VERY early draft, there were slated to be two OTHER races revealed to be living under humanity's notice on Earth at a later stage of the story: avian "airbenders" living in cities disguised as clouds, and fire-breathing dragonoids who consume stone and react to water as if it were acid. In this draft of the story, humans were to be eventually revealed as "fallen" earthbenders who forgot their elemental artform. Todd would have been the first human to regain the ability.
This concept essentially evolved into the four Clans of Sarnoth, whose general personalities are very loosely based on the same four elements in terms of "feel" (Sar'Teri: Earth, Stoic. Jin'Sorai: Fire, Passionate. Mor'Kama: Air, Aloof. Tel'Dora: Water, Nurturing.)