The right lane of northbound U.S. 61 South is closed to traffic as the Mississippi Department of Transportation works to complete a ditch-clearing project near Katherine Drive Thursday morning.  The project, which began about two weeks ago near Vicksburg Municipal Airport and worked its way north, is expected to be completed on Monday. By clearing the overgrowth and digging deeper ditches, MDOT hopes to improve drainage along U.S. 61 South.