Where is My Sewer Clean Out?

The "house main drain", what many people think of as the sewer line, is the main horizontal drain line under a home. As the main drain exits the perimeter of the house it connects to the "house sewer", essentially the outdoor portion of the sewer line. The house sewer then connects to the municipal sewer system or to a septic system.

Where the house main drain connects to the house sewer, code calls for a clean out. Because placing the clean out right at the perimeter of the home could prove inconvenient, it can be located up to three feet past the edge of the home.

To locate the clean out for the sewer line, start by looking for an "S" stamped into the concrete or painted on the curb near the street. This "S" marks the rough location of the buried sewer line as it connects to the city sewer. Look for the clean out in a straight line between the marker at the street and the part of the house where the house main drain is believed to be. The clean out should be no more than three feet from the house, along this line.

If you have a septic system, then the clean out should be between the house and the septic tank.

The Exceptions

Not all houses were built to code, codes have changed over time, sewers have been added after a home was built, any of these and many other situations can arise that may mean the clean out, if it exists at all, is not where it would normally be expected. If you know where the street side connection is, then follow the line between that point and the house.

Under ideal circumstances, the clean out is located inside concrete or plastic enclosure with a lid labelled "Sewer Clean Out". However, more often the clean out has been covered with dirt or grown over by landscaping. If you cannot find the clean out, you may have to do a little digging around where it "should" be located. A little exploration may reveal it under just a few inches of mulch or beneath the vines of a hearty plant.

In addition to the main sewer clean out, your home may have multiple other clean outs for the convenience of accessing lateral and vertical drain lines in your home. The clean outs may appear as capped stubs of pipe protruding from exterior walls. If you have access to a basement or crawl space, you may find clean outs there. Less common but still a possibility are clean outs in the attic. Attic clean outs can often be useful for clearing obstructions in the vent portion of the drainage system. Sometimes the clean out will appear as an "Y" or "T" in a pipe that seemingly dead ends. The dead end stub is actually a clean out.