BrianL,
Thank you for getting back with me. Before we bought the property I checked the flood maps. The property isn't in the 100yr flood zone (though, I'm very sure the SE section of the property gets very moist!). I'll run up to the property next time we get a monsoon through this way, but I doubt the lower part of the property gets 3' of standing water. (FEMA map att'd.)

Regardless, I absolutely understand that there will be troubling issues if I build a pond in a location where it gets washed out from time to time.

Do you know of anyone I can contact to start planning this pond?

Attached Images
Mexia - FEMA Flood Map.JPG