From a little while ago ...
The principal challenge of paddling in Lake Ontario in winter is not so much the water temperature per se, but the risk of hitting a chunck or piece of ice. Remarkably, even at approximately 1.5miles (2km) from the shoreline, one can easily discern 2-4foot pieces of ice. At a kayak cruising speed of 7-9knots (14-16km/hr), hitting such an "object" would most certainly result in a "miniature Titanic" scenario. Thus, early detection using mobile yet light sonar devices is paramount, so that immediate countermovements can be initiated.
