If the stream is a blue line stream on any map, you might not be allowed to dam it. Check with your counties NRCS office about the pond placement to see if it's OK, NOT the Army Core of Engineers.

www.hoosierpondpros.com

[Linked Image from lh6.ggpht.com]
http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).