Interesting this thread got revived a bit. I have set this stretch of water for a couple of weeks and have had decent success. Ten rats and three coon. Set it with colonies 551 conis and 1,5 on homemade platforms with bait like a hags setup. Connected on each type. Although the baited sets were more successful than anything. Debris was the number one issue. I clean colonies out every other day or so. Just grass moss and clutter. Nothing special really. Some things are easier in the strong current than slow or sitting water. For example our water is crystal clear. If you cnat see something because of mud just wait a second its all gone. Hard things are finding active runs. Not hard i guess just different way to look for them i suppose.
I set it up as an experiment really traps in the strongest current and weak different baits and such. One thing i found which surprised me i guess was that half of this waterway gets sunlight every day and the other is shaded by bank all day every day. I got zero catches on the shaded side. All catches except one rat were on the shore of the sunny side. This was very evident as i walked the line daily and caused me to look at other water areas i will be trapping different. Setting up a new line now about a half mile away from this location same waterway and the same is evident upon scouting. Sun side is hot and the shade side is blank. I wonder why i never seemed to notice this before in my trapping? Guess i never really trapped open canals like this before so maybe the trend didn't exist?