That easily accessible spot on the causeway may be as good as anywhere, just don’t limit yourself to the paved portion. There’s a nice 10-15 deep flat straight out that’s between two deeper channels heading under the bridges on either side. The trout seems to like cruising this. Once a couple stockings have happened there’s usually a good bunch of fish to be found.
I’ve had zero luck fishing off the dam and haven’t tried any other spots. In my kayak I usually fish down the south side, troll back and forth off the causeway (which is where I catch the most fish) then head back maybe hitting a couple spots where I found a fish or two on the way out