If you are referring to the area on highway 162 (oro dam blvd) heading towards 99 that can be great for bass early spring. That water is shallow and warms up fast. I lived in Oroville until 4 years ago. It can produce limits but not usually any size. I like to Carolina 6" plastics anywhere you can find a hump. Where the 162 bridge goes over the water there is rip rap on both sides. Try throwing a Fire Tiger crankbait on the east end of the bridge. Also at the south end of the afterbay there is a spillway where water is released back into the Feather River. This produces current and you may have luck with a dropshot. Good luck and fill me in on your results.