I am not saying you wont catch bass, it's just it is a big body of water with limited areas to fish so If you are in one spot all the fishing could be somewhere not accessible by foot.
That being said I have caught VERY large smallies down there! Your best bet is fish as close to the mouth of the river where it is heading out, the point there has very good potential. I also find that you better chances very early morning ( 4:30 through to 9:00 am ). especially during the summer.
One big issue is how the river is regulated early morning when power demand is lower the flow is slower as the day goes on and power needs go up they increase the flow, I can see it! I have been standing by a 6 foot rock and 1-2hrs later the rock is submerged! So these conditions effect fishing greatly.
( this is why you should always be aware of the water around you, you could be standing on a rock and 20 mins later you get cut off shore by water around you ) ALWAYS BE VERY CAREFUL DOWN THERE!! I cant say that enough about the lower.
Even if you don't catch anything you are always learning in the lower... not a bad thing, plus the views are awesome. Down by the glen and pebble beach the hike down is very enjoyable and again awesome scenery
If you have any questions about the Niagara river .PM me I fish that river ( lower and upper a lot ).