Rutting is the longitudinal vertical deformation of a pavement surface in a wheelpath, measured relative to a straight edge placed at right angles to the traffic flow and across the wheelpath, with a length/width ratio greater than 4:1.
A single instance of rutting is called a rut or wheel rut. Large ruts can hold enough water to result in vehicles aquaplaning in wet weather.
Rutting in unsealed roads can be corrected temporarily by maintenance grading, but resheeting and possibly drainage works may be required to correct the problem more permanently.
A major patch or a road reconstruction are possible options for sealed roads.