The Sunday before Memorial Day was a wonderful day to spend on the Oconomowoc River with friends. We put in at the first Concord Road bridge (there are two bridges on Concord Road, which caused some confusion for the friends we were meeting). Put in was decently accessible, although smelled pretty rank due to some dead fish laying around.
The river was for the most part clear and shallow. It does run through some suburban backyards for a while in the beginning, but for the most party is pretty marshy. Under the second Concord Road bridge there was little rock shelf to run, which sounded loud and scary on the approach, but was pretty puny once you went over it. A few bends after the bridge, we ran into a series of deadfall. The first one required getting out of our boats and hoisting them over the log. The next in the series did not make us get out of our boats but did require a tight turn to the left and then some grabbing of branches to get the boat in the direction to go over a passable log. The last required a limbo maneuver which was doable in a kayak. A canoe would probably have required a climb over.
The rest of the river was free from obstructions and we floated on to the Elm Drive takeout. Take out was a bit more mucky and with a lot of tall grass, but not too terrible. Shuttle was a quick run up Elm Dr to a right on Allen Rd which takes you all the way back to Concord. Would be entirely doable on a bicycle.
Mike Svob's "Paddling Southern Wisconsin" has a page on the Oconomowoc.
Map was clear and helpful.