If you can; go after the sun goes down. Fish OFF of, the boat docks at the marina. Shine a flashlight across, the surface. Use bobbers n' jigs; and fill your buckets!
P.S. On second thought, I learned about that many years ago. I'd suggest that you call ODFW, to be sure that night-time fishing for Crappie is allowed. I can't find anything, in the regs either way.