Here is a link to a web page showing Mississippi river maps with wing dams shown.
Link to web page with pool 4 maps
As others have advised, travel up and down the river passing between the buoys especially if going at higher speeds. You will begin noticing areas of the river that have surface motion due to the wing dams forcing water turbulence at the surface. These are not only along the main channel, but also exist in back waters. Some are concrete structures, but many are just rock piles deposited on the bottom. If fishing these, anchor above the wing dam and fish downstream. It is said that aggressive fish lie upstream from the structure, while less aggressive fish will lie on the downstream side, perhaps taking advantage of the slow water immediately behind the protection of the structure.