Vicksburg, Miss…The U.S. Army Corps of Engineers’ is enforcing safety rules for all operators of Off-Road Vehicles (ORVs) at its Mississippi lakes at Arkabutla, Enid, Grenada, and Sardis. These rules apply to any motorized vehicle designed primarily for, or capable of, cross-country travel on or over land, water, sand, snow, ice, marsh, swampland, or any other natural terrain.