We have a lot of bridges like this in my area my question is one box more productive than the others blind seting for mink the closest is the shallowest 4 inches to a foot the next 2 are 3-5 ft the furthest is 3 ft to a couple inches the inner walls are all traditional straight walls the two outside walls cone out so swift floods don't wash the ends out as bad there's no mud for tracks all gravel so no sign points to one over the others id also be interested to learn how you guys might blind set this for otters as well

I would set each side hugging the inside edge,up against the edge on the outside approach as well,keeping in mind that passers by can probably see the trap. Back up everything with baited pocket sets as well.

So 10 sets?

No,leave the middle alone,catch the mink coming from the bank going in…a set or two on each side. They run the bank and enter the water, and you can usually see where.

It's all gravel chunk rock and concrete so unless it's wet there's not any tracks

I would set both sides of the bridge and make 2 sets at each corner. And if you can access the land 100 yards downstream and upstream I would also set that area too. Some of those sets may have coon in them and you what enough traps in place to take the mink. The more traps the more chances of multiple catches.

If you don't have a exposed bait rule you could take a rat carcass and place a rock on top of it. Just leave a bit showing and place a trap in front of it. No more then a 1" of water over the trap.