Is it the main line?
The main line is the pipe every drain in the house empties into. When it clogs, problems show up in more than one place:
- Several drains slow or backing up at once
- Water rising in the tub or shower when you flush a toilet
- Sewage coming up through the lowest drain in the house, often a floor drain or basement shower
- Gurgling from toilets when the washing machine drains
If only one sink or one tub is slow, it is almost always that fixture's own drain. Start there instead.
Stop using water
When the main is blocked, every gallon you send down has nowhere to go but up through the lowest drain. Stop running the dishwasher and washer, and stop flushing until it is cleared.
Find the cleanout
Most homes have a sewer cleanout: a capped pipe near the foundation outside, in the crawlspace, or in the garage. If the line is backed up, the pipe may be full of sewage under pressure. Loosen the cap slowly and stand to the side. If sewage drains out of the cleanout, the blockage is downstream between there and the street.
Should you rent an auger?
Rental drum augers can clear a main line, but they are powerful machines. A cable that kinks or wraps can injure hands and arms, and cable stuck in the pipe turns a clog into a dig. If you have never run one, this is the job to hand off. Chemical drain cleaners will not clear a main line and leave caustic water for whoever opens the line next (see why we avoid chemical drain cleaners).
Clearing it is half the job
Main lines rarely clog for no reason. Roots, a sagging section, grease buildup, or a broken pipe usually sit behind the blockage. A camera run after the line is cleared shows which one, so you are not clearing the same clog every few months.