A note about ponds:
   To the best of my knowledge, there are no building codes anywhere in America that specifically address water gardens. That doesn't mean a municipality will not try regulating the way you install a water feature. Most try to restrict the size and depth. Sometimes people hear the word water and panic.  What the municipality fails to realize is the precedent has been set for what you are proposing.
 
        The B.O.C.A. (Building Organization Code Administration) contains a section about swimming pools that we've used to allow us to build ponds. It states that water features under 250 sq. ft. and 24 inches of depth are deemed landscaping. In essence, ponds up to this size do not require fencing. Since the popularity Of water gardens is relatively new, and cities do not have existing codes regulating them, B.O.C.A. sets the precedent they have been looking for. We have never been denied the right to build a pond since we started referring city engineers to B.O.C.A.

        When you construct a larger or deeper pond you are more at the mercy of the city. Still, we do not often have problems when we construct larger water features.