Why Your Drain Keeps Clogging, and What Actually Fixes It

Why does the same drain keep clogging?

A cable does one thing well. It cuts a path through whatever blocks the pipe so water moves again. It does not scrape grease off the wall, pull a root out of a joint, or lift a sagging section back into slope. The clog rebuilds on the same timetable because the cause never left.

When the same drain keeps clogging on a schedule, the schedule is the clue. Three families of cause cover nearly every repeat clog we see in Los Angeles homes: what goes down the drain, what the pipe has become, and what waits in the lateral past the house. Match your symptom in the table, then read the section that fits.

Symptom, likely cause, and the fix that lasts

Why do kitchen drains clog on a schedule?

The kitchen line is the repeat offender in most Valley homes, and geometry is why. The sink sits at the far end of the house from the sewer, so its branch runs a long way with very little fall. Grease leaves the pan as a liquid, meets cool pipe a few feet from the sink, and hardens on the wall. Coffee grounds and rice pack into that layer and set like concrete.

Homes built before the 1970s make it worse. Many carry kitchen waste in 1.5-inch galvanized pipe, and rust has left the inside rough enough for grease to grip. After decades of layering, the opening is the width of a finger. A cable punches through the center, and the ring of grease closes back in. Jetting removes the ring instead of drilling through it.

A disposal muddies the picture, since a unit that has jammed or lost power holds water in the sink the same way a clog does. If it grinds normally and the water still stands, the blockage sits farther down the line. One crew here holds both the plumbing and the electrical license, so the same tech resets a tripped circuit or replaces a dead switch on that visit, with no second contractor to point fingers at.

Why do bathroom drains slow down again and again?

Bathroom clogs are hair and soap, and the pipe decides how fast they build. Smooth ABS or copper lets most hair pass through to the main. Old galvanized steel and cast iron do not. Rust pits the inside, the bottom of the pipe grows channels and scale, and every strand of hair finds something to catch on. Soap scum then binds the hair into a mat that a plunger cannot shift.

We see this most in 1940s to 1960s houses across Burbank, Glendale, and the east Valley, where the tub still drains through the original steel branch. A cable pulls out a rope of hair, the drain runs for a few months, and the mat rebuilds on the same rough spot. At that point the pipe is the problem, not the hair.

Once the pipe is the problem, only two fixes last. Jetting strips scale and soap off the wall and buys real time on cast iron that still has thickness left. Galvanized branches that have rusted thin need replacement, usually with ABS, during a remodel or as a standalone job. A mesh screen over the tub drain cuts most of the hair load either way.

Is it one fixture or the main sewer line?

One slow sink is a local problem in that branch. Several slow drains at once mean the blockage sits past the point where their lines join, which puts it in the main line or the lateral. The house gives three warnings before a main line backup puts sewage in the lowest tub.

• A toilet gurgles or bubbles when the washing machine drains. The washer empties faster than anything else on the line, and a narrowing main pushes air back through the nearest trap.
• The lowest drain backs up when a fixture upstairs runs, because wastewater takes the lowest open exit.
• A sewer smell rises from a floor drain, the yard cleanout, or the base of a toilet.

Skip the store-bought snake on any of these. A 25-foot hand auger never reaches a lateral problem, and a rented power machine can wedge or snap in old pipe. A licensed crew clears the main through the cleanout, usually a capped pipe in the side yard, and the camera goes in once the line flows.

What is happening inside an old clay lateral?

Houses from the 1920s through the 1950s, which covers much of Highland Park, North Hollywood, Van Nuys, and Burbank, drain to the street through vitrified clay pipe. Each section is only a few feet long, so a lateral has dozens of joints, and every joint is a seam that can open. The clay outlasts the house. The joints give up decades earlier.

Roots are the most common find, and ficus, camphor, and jacaranda in the parkway are the usual sources. A fine root enters a joint, drinks, thickens, and grows into a net that catches paper and grease. A root saw on a cable clears it for a season, and the root grows back from the same joint every time. Jetting on a schedule keeps a light intrusion manageable; a joint that has failed needs repair.

Roots are not the only thing the camera finds. A belly is a sag in the run where water stands instead of draining, and solids settle in it until the line chokes. An offset is a joint that has slipped out of line, usually after decades of small earthquakes, and its edge catches paper on every flush. Each of these brings the clog back at the same footage no matter how often you snake.

Do chemical drain cleaners fix a clog that keeps coming back?

No, and on an old house they make the next visit worse. The lye and acid formulas work by generating heat. That heat softens PVC joints, attacks the zinc and iron in a galvanized trap, and does nothing to a root mass or a belly. The product rarely dissolves the whole clog anyway; it opens a channel, sludge settles farther down, and the pipe closes again.

There is a safety problem too. Standing water in a sink after a bottle went in is caustic, and the tech who opens that trap next takes it on the hands and face. Tell whoever comes out what you poured and when. A drain keeps clogging for a physical reason, and the answer is mechanical: a cable, a jet, or a repair of the pipe itself.

Enzyme products belong in a different category. They digest organic film slowly and will not open a blocked pipe, which makes them fair maintenance after jetting and useless during a backup.

Snake, hydro jet, or camera: which one is the right call?

Each tool answers a different question. A cable machine gets water moving right now, and for a first-time hair or paper clog that is the whole job. Our drain cleaning visits start there on a line with no history.

Hydro jetting answers a second question: can the pipe wall go back to bare material so the buildup starts from zero. A jetter pushes high-pressure water through a nozzle that scours grease, cuts roots, and strips scale, then flushes the debris on to the main. On a kitchen line that clogs every few months, jetting turns a quarterly emergency into a yearly maintenance item.

The camera answers the question that matters most for a repeat clog: why. A sewer camera inspection runs a lens through the cleaned line with a footage counter on screen. You watch with the tech and see the joint the roots come through, the standing water in a belly, or the lip of an offset. A locator marks the spot and its depth on the surface. The fix then matches the finding: a jetting schedule, a spot repair or lining through our sewer line repair crew, or a new branch line inside the house.

The order depends on the pipe. Jetting comes first when grease or roots coat the line, because the lens only sees what the grease lets it see. The camera goes first on any clay or thin galvanized line, since a collapsed section needs a repair, not more pressure.

Who is responsible for the sewer lateral in Los Angeles?

The homeowner is responsible for the whole run. In the City of Los Angeles the private lateral belongs to the property from the house to the tap at the city main, sidewalk and street included. Only the main itself falls to the city. A root mass at the property line is your repair, and camera footage settles any argument about where a backup started.

Permits follow the same line. A lateral repair inside the city limits goes through LADBS; work under the street needs a separate right-of-way permit and sometimes traffic control. Burbank, Glendale, and Pasadena each run their own permit counters, with slightly different steps. Cleaning and jetting need no permit anywhere, since they change nothing about the pipe.

A+ Electric & Plumbing is a licensed electrician and plumber with a shop in Tujunga, and the crew that clears a Valley lateral reads the footage with you and puts any repair in writing first. For a single electrician and plumber in Los Angeles who can check the lateral and the rest of a 1950s house on one visit, start with our Los Angeles plumber team.

What prevention actually keeps drains clear?

Prevention works when it matches the cause. A strainer does nothing for roots, and a jetting schedule does nothing for a hair clog. Start with what the camera found.

• Kitchen: pour cooled grease into a can, scrape plates into the trash, keep coffee grounds out of the sink, and run hot water for half a minute after washing pans.
• Bathroom: a mesh screen over the tub and shower drains, cleaned weekly. Keep wipes out of the toilet, flushable label or not; they reach the lateral intact.
• Old cast iron or galvanized branches: plan the replacement instead of snaking the same rough pipe every season.
• Clay lateral with roots: jet on the schedule the camera sets, and re-scope every few years to catch a failed joint.
• Belly or offset: no habit fixes a sag or a lip, so repair the section once.

Low-flow toilets and faucets send less water through the same old pipes, so solids settle sooner in a flat lateral. A full tub drained now and then keeps the main moving. Current ranges for cleaning, jetting, and the camera are on the service pages above, and written estimates are free.

Frequently asked questions