joerocker:
Your idea about filling in the back of the dam with stone is a good idea. Use stones no smaller than 12" and wrap a chain link fence around the stones. If you get a chance to add topsoil and get grass planted then stake square hay bales across it to slow done the water enough to let your grass establish. If you need more information or would like to talk to me directly you can call my office at 1.800.822.3478 or email me at mikeotto@ottosdirtservice.com and Sheri will set you up a phone appointment. She is in the office from 8 to noon monday thru friday.
Otto