Crappies can be common even during the winter months near the dam, especially behind wingdams that have deep pockets behind them. Like Jason said, find a current seam, but find one along a deeper pocket where the water is somewhat protected from hard current and you’ll find fish.
The wingies will be in high traffic areas, but the back channel will offer more tradional crappie water and cover. Down stream from Everts an the main channel you will soon be able to sneak into both Baypoint Harbor and the harbor at Colville [below the city of Red Wing]. Both of these locations can be hot for crappies.
Be sure to talk with Dean at Everts. He has some of the best area-specific crappie tackle on hand in colors that work best.. …something new to offer anglers this year.