if ya are going to be trapping there, ya would have a good chance of losing one or more of your conis.
for settin up on a dam, by bro and i kick a hole in the dam big enough for a 330 to fit in. the beaver cant stand to lose that water and will try to fix the breach. we have caught many beaver like this.
also for a dam, ya might set a 220 on top of the dam (if there is a indentation from traveling beaver) your other critter seasons are prolly out now, so ya might not want to do this. (keep in in mind for next season)
look for slides along the banks where the beaver enter and exit the water, center set a 330, 220, or snare there (if using a foothold, go off center bout 2", i suggest a #4 or #5 dls).
also look for a bank den. these are usually bout 3-4 feet under water, but if ya find one, do not hesitate to put a 330 (on a slide wire) there. this will produce many beaver. use a slide wire because, if there are more than one beaver there and they see a dead sibling, they are likely to move on and avoid that area.
look for beaver chewing close to the bank. if ya find one of these, take some fresh cutting and wire them to the triggers of you coni. we have taken several this way.
hope this helps.
mallarddrake85