Which drain is clogged
A single fixture. A sink, tub or shower slowed by hair and soap is usually blocked near the opening, and it’s the smaller job. The kitchen line. Grease and food set up past the disposal, so the clog is often longer than it looks. The main sewer drain. When several drains are slow at once, or the tub fills when a toilet flushes, the blockage is in the main line. A main line clog costs more than one sink: the pipe is bigger, the run longer and the clog harder to reach.
How we get into the line
An outdoor cleanout gives a straight path into the main line. With no cleanout, or one lost under a flower bed, the plumber often has to pull a toilet, which takes longer and puts the work inside your house. Adding one makes every future main line call simpler; see sewer cleanout installation.
How far down the clog is
A clog a few feet from the drain clears quickly; one far down the main line takes more cable and more time. Houston Public Works uses the cleanout to mark where your pipe stops and the City’s begins. If sewage is standing in the street-side cleanout, the blockage is usually the City’s, and the call is to 311.
Cable or hydro jetting
A cable cuts through a clog and is the right first step for most stoppages. Hydro jetting washes grease and scale off the pipe walls, which suits a line that keeps slowing down after it’s snaked. It’s a bigger job and priced that way. It needs pipe that can take the pressure, so we don’t jet old cast iron or clay lines.
What the clog is made of
Hair and soap usually clear in one pass. Grease coats the walls and comes back; Houston Public Works says grease and wipes cause about 70% of the city’s sewer overflows. Wipes don’t break down, even “flushable” ones. Tree roots grow in through cracks and open joints, often where Houston’s shrink-swell clay has shifted old pipe. Cutting them restores flow, but they grow back until the section is repaired.
A camera look when it keeps coming back
When the same drain keeps clogging, we can run a camera through the line so you see what we see: buildup, a sag, a cracked joint or roots. If it shows a broken or sagging pipe, the fix is a repair; see the sewer line repair cost guide.
Sources: Houston Public Works, Protect Our Pipes · Houston Geological Society, Beaumont clay · U.S. Census Bureau, ACS, year structure built (Houston). Updated November 2026.
