Tucked alongside the native tallgrasses of the Konza Prairie within the undulating Flint Hills of Riley and Pottawattamie counties in northeast Kansas, is the Tuttle Creek Dam and Lake. This engineering marvel of the midwestern United States, is a 7,500-foot-long earth and rockfill dam that chokes off the Big Blue River, creating the second largest reservoir in Kansas with a total capacity of over 2.1 million acre-feet of water.