Brian Povandra, a Rapid City Fire Department ice rescue instructor, holds up a fragment of ice from the lake to show Airmen from the 28th Civil Engineer Squadron Fire Protection Flight the thickness of the ice they were standing on at CanyonLake in Rapid City, S.D., Feb. 12, 2019. The thickness of the ice on the lake that day ranged from 2 to 10 inches. (U.S. Air Force photo by Senior Airman Michella Stowers)