Not so scary. Ice is very strong when solid.
While going to school in Helena, Montana a couple buds and I would regularly ride out on the frozen Canyon Ferry reservoir on the Missouri river to ice fish. In those kinds of temps the ice was at least 10 inches thick and supported cars and pickup trucks, too.
Even in sub-zero weather you could still hear the ice a hundred yards away cracking. THAT got a bit un-nerving sometimes, but as long as the temps stayed below zero it was all good.