It has inclined flat bars spaced apart and is used to prevent large floating wastes from travelling further into intake structure, pumping station and treatment plants. The inclined bar screen is stationery and is cleaned by a mechanized suspended grab which rakes the screen upwards and then moves laterally to deposit the raked waste to a waste discharge bin. In the next cycle the suspended grab moves laterally to clean the screen portion adjoining to the portion cleaned in previous cycle and in this way over time cleans the entire bar screen area.