Test utilizing a plunger or empty serpent to clear the stoppage. Use a camera inspection to identify the cause of the backup. Consider hydro jetting or trenchless repair to clear the blockage and repair the sewer line. If the problem persists, it’s best to call a professional plumber. A gas line leak is a serious plumbing problem that requires immediate attention. Gas leaks can be caused by damaged gas lines, corroded connections, or faulty appliances.