Vicksburg, Miss…The U.S. Army Corps of Engineers’ is enforcing a safety requirement for all operators and passengers while riding certain vehicles at its Mississippi lakes at Arkabutla, Enid, Grenada, and Sardis. Operators and passengers must wear helmets at all times when operating or riding in recreational off-highway vehicles, all terrain vehicles, all terrain cycles, and other vehicles that travel on non-highway tires and designed specifically for off-road usage. All vehicles shall be operated in accordance with posted restrictions and regulations at each site.