Trustee Rob Scheithauer took some pictures at the Rowland Nature Preserve on January 4, 2013, to show the purpose of the windmill. When the windmill blades turn they are pumping air to an air stone that is tied below the two duck decoys. The air generated from the windmill is keeping the lake from totally freezing and this generates oxygen in the water so the fish can survive the winter. The diameter of the water ring is approximately 20′. A word of caution for the ice fisherman: keep your distance from this water ring because, obviously, the ice is thinner in this area.