I'm thinking weeping willow. Although if it will cause issues I may stick to some cypress trees...since I am in south Louisiana.
I've got weeping willows in my yard, close to the big pond. Haven't had any trouble with them spreading....word of warning though if you don't have a ton of experience with them...they'll take a LOT of water, and they're dirty. They drop a ton of limbs annually.
With that said, I really enjoy mine. They're a very pretty tree.