U.S. Air Force Senior Airman Joshua Slater, 100th Civil Engineer Squadron water and fuels system maintenance journeyman from Springfield, Mo., records the water pressure flowing through an open hydrant June 3, 2015, on RAF Mildenhall, England. There are no parameters on the residual water pressure; however, if the residual pressure is more than several pounds per square inch below the static pressure, it necessitates the need to investigate the situation as a foreign object may be constricting the flow of water. (U.S. Air Force photo by Gina Randall/Released)