If you're looking for it from the river, all I can tell you is good luck. We could hardly find the mouth; it was a narrow flowage barely visible in the grass. But once you get out of the river plain and start walking into the woods, this stream takes on a life of its own. It rushes over rocks and sand, twisting and turning through floodplain forest. As soon as we took the first turn into the woods, armed with backpack electrofisher, my coworker and I found our first brook trout.
A bit about electrofishing...it is the accepted way to sample small streams. The fish are stunned by an electrical current, but not enough to kill them. They are netted, usually put into a bucket, and when there are a good number of fish we stop sampling to measure them, take scale samples (to determine ages), and release them. Of course, it is more effective than rod and reel fishing, which is probably why I hardly fish any more. The action is just too slow. :)
Back to this small stream...as it wound its way up the St. Croix bluffs, we shocked up brook trout after brook trout, and hardly anything else. There were hardly any pools more than a foot deep, but still they were there in the cool spring water. Most of them were small, averaging about 4 inches, but we did get a couple 8 inchers. We ended up with over a hundred brook trout, from the mouth of the stream to where the water got too shallow to find any more.
Brook trout amaze me. They survive in the smallest of streams, as long as water temperatures are right. They are beautiful fish.