Your Ultimate Sewer Line Cleanout Guide (2024)

Most folks confuse the terms “cleanout” and “cleaning out.” A sewer cleanout is a fitting, and they’re typically installed at main elbows, the far end of the system, and where the system meets the municipality’s sewer system. They have threaded caps with square knobs that plumbers can remove to feed a snake, jet or other tools down.

Cleaning out a sewer system is an activity—not a fixture. This occurs when a plumber snakes the system or the homeowner performs some basic maintenance. Cleaning out is the focus of this article.

Another set of terms that might get confusing is sewer system and drain system. Both systems remove waste from a home and funnel it toward the municipality’s treatment center, and they do tie in together. However, a sewer system is technically the portion of the system outside of the home, while the drain system is the one inside the home that connects to the sinks, toilets and other fixtures.

NOTE: DIYers should avoid touching the sewer system as this usually requires a license from the city. They do not need a license to maintain their drain system inside the home. But, for the sake of this article, we’ll refer to the system within the home as a sewer line or sewer system.

Sewer lines are fairly basic. They consist of pipes that remove waste away from fixtures like sinks, toilets, showers, and dishwashers, as well as traps that fill with water to prevent sewer gasses from backing into the home.

These fittings and fixtures are all pitched toward the sewer outlet (where the home’s system meets the municipalities), with many elbows and tie-ins along the way. There are also vents installed at certain points to prevent a vacuum from building up and draining the traps. All of these items together are known as the home’s drainage system, but we’ll refer to them as sewer lines or the sewer system for simplicity’s sake.

Where Is Your Main Sewer Line?

The main sewer line is the large, 4-inch or 6-inch pipe that all of the home’s drain pipes run into. This pipe is usually located in the basem*nt, running along the perimeter of the basem*nt toward the area where it meets the city’s sewer system.

In most cases, the main sewer line will be a white plastic pipe called “PVC,” but it may also be a black cast iron pipe in older homes.

At the ends of these pipes is the actual cleanout. This fitting provides the plumber with unrestricted access to the system, allowing them to snake, jet or blow out the system without having to work through a fixture like a sink or a toilet. Homeowners should locate their cleanouts as well, as these can be helpful places to start when issues occur.

There are signs that a sewer line or drain system needs to be cleaned. Those signs include:

• Slow drainage
• Smells emitting from the drain
• Gurgling sounds coming from drains
• Clogging frequently

Many of these issues can occur if the system is full of build-up and waste. In these cases, it may be necessary to perform a sewer line cleaning to bring things back up to snuff.

There are a few ways to perform a sewer line cleaning, but the safest option for most homeowners is to use a cleaning solution made from baking soda and vinegar. Stock up on both items, as you’ll need to apply them in multiple areas throughout the home. We also suggest using safety glasses and gloves for this process.

1. Start at the sink or toilet closest to where the home’s drain system meets the city’s sewer system. For toilets, shut off the water supply at the wall valve and flush as much water out of the toilet as possible.
2. Pour ½ cup of baking soda into the drain, followed by ¼ cup of vinegar. This will create a lot of foam, but the baking soda’s abrasiveness will break down the grease as it flushes down the system.
3. Allow the drain to sit for 15 minutes before flushing with hot water for two or three minutes.
4. Repeat at the next closest drain.

Starting at the closest drain will prevent grease that flushes down the system piling up and create a clog. Also, do note that the abrasiveness of this cleaning solution can break pipes down over time, so it’s best to use this method if it’s not necessary.

You can also use an enzyme-based cleaner down the drain. Each product’s application is different so be sure to read the directions on the package. However, generally speaking, homeowners simply pour these cleaners down the drain and flush, allowing the enzymes to break down waste and grease as they float down the pipes.

WARNING: Cogs in the main line will probably require a plumber’s attention. While small snakes may work for fixtures like sinks, toilets and showers, main lines require larger, more powerful snakes, and DIYers can get seriously hurt if they don’t know how to use these snakes properly.

That said, if a DIYer is confident that the blockage is close to the cleanout and they can clear it with a smaller, handheld snake, they can try these steps:

1. Locate Cleanout and Remove Cap

Locate the cleanout and carefully remove the cap with a pipe wrench. Take care not to break the cap, and be aware that there will probably be some backup fluid and pressure on the other side of the cap.

2. Look for Blockage

Shine a flashlight down the pipe and look for the blockage.

3. Guide Snake Down

Carefully feed the snake through the pipe, guiding it down to the clog.

4. Maintain Pressure and Spin

Once the snake hits the clog, maintain pressure on the snake but stop feeding additional cable into the drain. Continue spinning the handle or drum until the snake catches the clog or breaks through it.

5. Pull Cable Out

Carefully pull the cable straight out to remove the stoppage, coiling it into the drum as it comes out. If the cable won’t budge, reverse the snake to back it out. Repeat until you’re able to clear the clog.

Here are some easy tips that will help keep your drain line clean:

• Throw out grease, don’t rinse it down the drain
• Pour boiling water down the sink and shower drains once a week
• Pour a mixture of dish soap and boiling water into each drain
• Use baking soda and vinegar to clean drain pipes
• Dump a teaspoon of salt into a drain, followed by ¼ cup of white vinegar. Let sit for an hour and then flush with hot water.

Bottom Line

In many cases, a DIYer can handle their own sewer line cleanout. All it requires of them is a little patience and know-how. But, for situations that may require a heavy-duty snake, it’s best to call a sewer line repair professional or professional plumber. But, you can avoid both of these scenarios by practicing routine drain line maintenance.