Drains

Finding the cleanout before you need it

The cleanout is the difference between a plumber working with your sewer line and working against it. Here is where it sits on a typical Costa Mesa property, what the fitting looks like, and what your options are if the house was built without one.

Updated August 20, 2026 ·Drain Cleaning & Hydro Jetting

Your main sewer cleanout is almost always a capped pipe three or four inches across, standing at ground level outside the house. On a Costa Mesa slab home it usually sits against the exterior wall closest to the main bathroom, or somewhere on a straight line between that wall and the street. The plug is brass, black plastic or white, and often has a square lug on top so a wrench can turn it. If the garden has been redone since the house was built, there is a good chance the plug is under two inches of soil, bark or a paver, still exactly where it always was.

What the fitting looks like above ground

Underground, the cleanout is a wye or a tee cut into the sewer lateral with a short riser running up to the surface. What you see is the top of that riser. On older properties it is cast iron with a dark, slightly domed brass plug. On lines repaired or replaced later it is white PVC with a plastic plug. Some sit inside a round concrete or plastic box set flush with the ground, and you have to lift the lid before you can see the plug at all.

Two things get mistaken for it. A vent is open at the top and runs up through the roof or up an outside wall, so it never has a plug near the ground. An irrigation valve box is usually rectangular and green, and holds wires and small valves. If you lift a lid and see anything electrical, put the lid back.

Where to look, in order of likelihood

Walk the outside of the house before you dig anything. Bathrooms and kitchens sit at one end of the drain system, and the lateral leaves the house from the nearest wall, so the search area is smaller than it feels.

Against the exterior wall closest to the main bathroom, within about three feet of the foundation.

On a straight line from that wall towards the street, because a lateral runs straight unless something forced it not to.

Near the front kerb or in the parkway strip, where a second opening is often set close to the property line.

In the garage floor, particularly where a laundry hookup sits along the same wall as the bathroom plumbing.

Under the shrubs along the side yard, which is where most buried plugs turn up once you rake the top inch of soil back.

Beneath a paver, a later concrete pour or a deck board, which is why a plumber sometimes has to open ground even when the location is certain.

Why a 1970s house here may have none

The median Costa Mesa home was built in 1972, and 68 per cent of the housing stock went up before 1980. Plenty of those houses left the builder with no ground-level cleanout at all. The only way into the drain was through the roof vent or by pulling a toilet, which is slow work and which puts a cable into the line at an angle that does the plumber no favours.

That does not settle the question, though. Laterals get repaired over fifty years, and a repair usually adds an opening. Before deciding there is nothing there, look for a patch in the driveway concrete, a rectangle of newer stucco at the base of a wall, or a strip of side yard where the soil sits differently from everything around it.

Your pipe runs to the middle of the street

Costa Mesa Sanitary District handles the sewer here, and the split of responsibility surprises people. The homeowner owns the lateral for its whole length, all the way to the point where it connects with the district main, and that main is usually under the middle of the street. So a blockage sixty feet from the house, out past the kerb, is still on your side of the line.

That is what makes a cleanout worth having. Without one, reaching a problem at the far end of the lateral means working from a roof vent or a pulled toilet across the entire distance. With one, a camera and a jetting nozzle go in at the right height and the right direction, and the job stops being an argument about access.

One opening or two

A single cleanout points one way. A two-way cleanout has a fitting that opens both towards the house and towards the street, so a technician can work in either direction from the same hole. If a plumber says the line is blocked but tools will only go one way, that is what they are describing. When ground is being opened anyway, the two-way version is the one that earns its keep later.

Putting one in before the next backup

The Sanitary District runs a rebate programme covering either a CCTV video inspection of the lateral or the installation of a ground-level cleanout. Terms change, so confirm the current ones with the district directly rather than taking a contractor’s word for it. Either way the useful order is camera first: film the line, find out what is actually in it and how far out it sits, then decide where an opening belongs.

The right place for a cleanout is not always the easiest place to dig. It wants to be on the run of the pipe, at a point where a cable and a jetter can reach both the house and the street connection without fighting a bend on the way.

While the drain is backing up

Stop using every fixture in the house, including the ones at the far end, because they all feed the same lateral.

Leave the washing machine and dishwasher alone, since both dump a large volume at once and both will find the lowest opening in the building.

If water is rising through a shower or a garage floor drain, read that as the system telling you the blockage is downstream of everything, not in that fixture.

Keep chemical drain openers out of it, because somebody is going to have their hands in that water within the hour.

One last thing worth knowing. If you find the plug and the ground around it is wet, or the threads are weeping, leave it closed and say so when you call. A cleanout with a full line behind it empties into the yard the second it is opened, and a sewage spill across the garden is a bigger problem than the blockage that caused it.