Your mainline is your main sewer line. It’s the line that goes from the home, industrial or commercial building into the city connection or your septic tank. All of your drains dump into a main sewer line or mainline. A mainline can back up, clog, brake and need repair.
These sewer problem warning signs are often a good indication your sewer line may need replacing (or, at the least, need some maintenance or repair work): Drain backups or persistent slow drainage. Gurgling sounds in drains. Back ups. Overflows. Foul sewage smells.
If you are experiencing any of these signs, you need professional help to repair your main drain and sewer line.