ALLONS, Tenn. (Dec. 15, 2021) – The first Clean Marina flag to fly over any marina in the U.S. Army Corps of Engineers Nashville District and Cumberland River Basin was at Willow Grove Marina located on Dale Hollow Lake in Clay County, Tennessee. Fifteen years later, with long-term family and staff carrying on the effort, Willow Grove Marina completed its recertification as a Clean Marina for a third cycle.