Bill Chelmowski, a marine machinery mechanic with the

Bill Chelmowski, a marine machinery mechanic with the U.S. Army Corps of Engineers' St. Paul District, uses an ice auger to drill a hole into Lake Pepin, near Wabasha, Minn., Feb. 13, 2013, during the first Mississippi River ice surveys of the year. The district conducts annual ice surveys to help the navigation industry determine when it is safe to break through the ice. Lake Pepin, located on the Mississippi River between Red Wing and Wabasha, Minn., is used as the benchmark because the ice melts slower in this area due to the lake width and the slower current. (U.S. Army photo by Patrick N. Moes/Released)