It's not normal to see higher CPU usage than that. CCD isn't generally a high performing game, sadly. I'd recommend taking the visibility slider down, as it takes quite some FPS in city settings. I've also turned down some of the reflections and other options. I tried noticing a difference, but there is none. Try adjusting down settings like mirror reflection and see if you can see a difference. If you can't, just keep it on a lower setting. I've gotten up to a steady 60 doing this.
Also, a lot of traffic will severely hamper your performance. Try 30-40% and see if that clears some things up. Sadly, the game doesn't render its mirrors very efficiently, which is what seems to be a big FPS hog in most cases. Try playing with virtual mirror settings, too.
Try also not having more than 2X AA (16X AF is no performance cost these days, so always go with that) - turn off transparency AA settings, as they can be huge to gigantic performance droppers, especially in the case of super-sampling and especially SGSS (sparse grid super-sampling).
2X AA helps a lot on aliasing (the stepping edge effect), and barely takes any performance.
Turn off v-sync and triple buffering, too, for this game.