Abstract: A molded structural plastic grate is received within a recess defined by a rim at the top of a structural plastic catch basin which also serves as a girth beam for strengthening the top of the basin. Bottom portions of the basin are rounded to provide a dome section for strengthening the bottom of the basin. The four corners of the basin reinforce it against buckling under weight placed on top of it. Each side wall of the basin is formed to include a breakout section adapted to be easily removed to provide a drain pipe receiving opening. The portion of the side wall surrounding the opening is adapted to be received within a groove portion of a section of corrugated plastic pipe.