Using a plank to reach solid ice is very common here - and not dangerous at all. What happens is that the lakes begin to rise with incoming water. The ice sheet "fit" the shore with lower water, but as the water rises, the sloped banks create a band of open water or thin ice all around simply because the lake is wider now. Using a plank or ladder between solid shore and solid ice solves the dilemma of how to get across that band.
