Travelling Grit Scrapers for single, twin or triple type basins manufactured as full wall, half Wall, steel profile or truss beam according to static calculations and requirements. The system consists of a travelling gantry over the channel which carries the grit and grease removal systems. Bridge is mounted on end carriages at both sides which have two polyurethane tired wheels with two guiding wheels or steel wheels driven on rails with or without pinion rack. Speed reducing unit includes a gearbox for required gentle slow movement and optionally a torque limiter. The settled grit can be either scraped to the collection pit or extracted by means of airlifts or submersible pumps. Also floated grease is scraped towards the removal channel by means of straight skimmers.