Shuǐguǎngōng zhǐ yòng le bàn ge xiǎoshí jiù bǎ dǔzhù de xiàshuǐdào shūtōng le.
The plumber cleared the blocked drain in just half an hour.
Tips
usage
水管工 is the everyday word; 水管工人 is the fuller form, and in casual speech people say 修水管的 "the pipe fixer". Other trades named with 工: 电工 (electrician), 焊工 (welder), 木工 (carpenter).