Mark - sorry about losing the lambs - clearly Sam needs to be free......
Maybe the regulations are different in our state - but livestock must be fenced 25' back from a drain or stream - BUT - a farmer can plant a field right to the lip of the ditch, and if he's spreading manure and some gets through into the ditch..... unless our DEQ SEES IT HAPPEN - it didn't. That's the battle I've been fighting for the last year in a watershed that's been delivering e-coli to our lake for decades....