I'd like to build my own marsh on my hunting land.. I guess I am just looking for some tips. Like how wide should my dam be.. my idea is to take this flat creek bottom and just push dirt out from the middle build a dam on 3 sides. One side is a hill.. But my question is I'd like to keep part of it empty during the summer so I could plant corn or rice to attract waterfowl during the fall and winter. What kind of valve or levee system would work best?