Interest for high speed weigh-in-motion of vehicles, or HS-WIM keeps growing worldwide. The main purpose of such systems is checking weights of vehicles in a self manner, in order to impose a penalty to overloaded ones. Overloaded vehicles may cause several problems such as safety issues, road deterioration or unfair competition. Walloon Public Service (WPS) has dealt with the settings and approval of a HS-WIM system in Belgium. The latest resurfacing of the roadway around the prototype provides good-quality data that allows for reaching excellent results in terms of accuracy of the weight estimation. Therefore, direct weight enforcement may be activated since the system has a type approval certificate to be used in accordance with legal metrology requirements.