Goldhunter,
With the cold I suspect that they have well in excess of 12 inches. Any ice fishers know for sure what ice thickness currently is?
12" is more than enough to set up a rig on. A couple more weeks of this and it will be 24 inches+. All they need to do to accelerate freezing/thickening is pack the snow down to get rid of its insulating effect. No need to (flood) build up the ice when Mother Nature will do it for us this year.
.... Been There